TIIE HEALTH CONSEQUENCES OF SMOKING FOR WOMEN a report of the Surgeon Genera/ u S DEPARTMENT 0~ Pbllc Health serv,ce HEALTH AND HUMAN SERVlCES o'flce of the AssIstant Secretary for Health onw on Smoking and Health c. The Honorable Thomas P. O'Neill,Jr. Speaker of the Rouse of Representatives Washington, D.C. 20515 Dear Mr. Speaker: I hereby submit the 12th annual report that the Department of Health, Education, and Welfare (DHEW) has prepared for Congress as required by the Public Health Cigarette Smoking Act of 1969, Public Law 91-222, and its predecessor, the Federal Cigarette Labeling and Advertising Act. This report is one of the most alarming in the series. It clearly establishes that women smokers face the same risks as men smokers of lung cancer, heart disease, lung disease and other consequences. Perhaps more disheartening is the harm which mothers' smoking causes to their unborn babies and infants. The report is not all bad news. It presents recent data showing that women are turning away from smoking in response to the warnings of government, voluntary agencies and physicians. The precipitate rise in women's deaths from lung cancer and chronic lung disease demand that this trend away from cigarettes be accelerated. Our scientists expect that by 1983, the lung cancer death rate will exceed that of any other type of cancer among women. Citizens of our free society may decide for themselves whether to smoke cigarettes. The health consequences of this decision make it imperative for their government to assure that the decision is an informed one. This series of reports is one way in which DHEW is striving to meet this critical responsibility. Patricia Roberts Harris PREFACE This report is more than a factual review of the health conse- quences of smoking for women. It is a document which chal- lenges our society and, in particular, our medical and public health communities. This report points out that the first signs of an epidemic of smoking-related disease among women are now appearing. Be- cause women's cigarette use did not become widespread until the onset of World War II, those women with the greatest inten- sity of smoking are now only in their thirties, forties, and fifties. As these women grow older, and continue to smoke, their bur- den of smoking-related disease will grow larger. Cigarette smok- ing now contributes to one-fifth of the newly diagnosed cases of cancer and one-quarter of all cancer deaths among women- more cancer and more cancer deaths among women than can be attributed to any other known agent. Within three years, the lung cancer death rate is expected to surpass that for breast cancer. A similar epidemic of chronic obstructive lung disease among women has also begun. Four main themes emerge from this report to guide future public health efforts. First, women are not immune to the damaging effects of smoking already documented for men. The apparently lower susceptibility to smoking-related diseases among women smok- ers is an illusion reflecting the fact that women lagged one- quarter century behind men in their widespread use of cigar- ettes. Second, cigarette smoking is a major threat to the outcome of pregnancy and well-being of the newborn baby. Third, women may not start smoking, continue to smoke, quit smoking, or fail to quit smoking for precisely the same reasons as men. Unless future research clarifies these differences, we will find it difficult to prevent initiation or to promote cessation of cigarette smoking among women. Fourth, the reduction of cigarette smoking is the keystone in our nation's long term strategy to promote a healthy lifestyle for women and men of all races and ethnic groups. `lhe Fallacy of Women's Immunity All of the major prospective studies of smoking and mortality have reached consistent conclusions. Death rates from coronary heart disease, chronic lung disease, lung cancer, and overall mortality rates are significantly increased among both women and men smokers. These risks increase with the amount smoked, duration of smoking, depth of inhalation, and the "tar" V and nicotine delivery of the cigarette smoked. In these studies, conducted during the past three decades, relative mortality risks among female smokers appeared to be less than those of male smokers. It is now clear, however, that these studies were comparing the death rates of a generation of established, lifelong male smokers with a generation of women who had not yet taken up smoking with full intensity. Even those older women who reported smoking a large number of cigarettes per day had not smoked cigarettes in the same way as their male counterparts. Now that the cigarette smoking char- acteristics of women and men are becoming increasingly simi- lar, their relative risks of smoking-related illness will become increasingly similar. This fallacy of women's apparent immunity is clearly illus- trated by differences in the timing of the growth in lung cancer among men and women in this century. Lung cancer deaths among males began to increase during the 193Os, as those men who had converted from other forms of tobacco to cigarette smoking before the turn of the century gradually accumulated decades of inhaled tobacco exposure. By the time of the first retrospective studies of smoking and lung cancer in 1950, two entire generations of men had already become lifelong cigarette smokers. Relatively few women from these generations smoked cigarettes, and even fewer had smoked cigarettes since their adolescence. Those young women who had taken up smoking intensively during World War II were only in their twenties and thirties. In 1950, women accounted for less than one in twelve deaths from lung cancer. Thereafter, the age adjusted lung cancer death rate among women accelerated, and the male predominance in lung cancer declined. Lung cancer surpassed uterine cervical cancer as a cause of death in women. By 1968, as the findings of many large population prospective studies were being published, women accounted for one-sixth of all lung cancer deaths. These studies found that women cigarette smokers had 2.5 to 5 times greater death rates from lung cancer than women nonsmokers. By 1979, women accounted for fully one-fourth of all lung cancer deaths. Over the next few years, women cigarette smokers' risk of lung cancer death will approach 8 to 12 times that of women nonsmokers, the same relative risk as that of men. Lung cancer has four main histological types: epidermoid, small cell, adenocarcinoma, and large cell carcinoma, As several studies have shown, the incidence of each of these types of lung cancer displays a clear relationship to cigarette smoking among both men and women. Epidermoid and small cell lung cancer appear to be more prominent among men, while adenocar- vi cinema of the lung now appears to be more prominent among women. The recent acceleration of lung cancer incidence among women has in fact been more rapid than the corresponding growth of lung cancer among men in the 1930s. Again, this dif- ference in the initial rate of acceleration of lung cancer inci- dence does not refute the demonstrated causal relation between cigarette smoking and lung cancer among both sexes. Instead, differences in the rate of increase of lung cancer incidence may reflect changes in the carcinogenic properties of cigarette smoke, the style of cigarette smoking, or the interaction of cigarette smoking with other environmental hazards. It is noteworthy that those men who died of lung cancer in the 1930s came from a generation that had gradually converted to cigarettes from other, non-inhaled forms of tobacco. By con- trast, the first regular tobacco users among women were almost exclusively cigarette smokers. The 1979 Report on Smoking and Health documented numer- ous instances where cigarette smoking adds to the hazards of the workplace environment among men. Among women, this report reveals two such occupational exposures- asbestos and cotton dust-which have been clearly demonstrated to interact with cigarette smoking. The fact that evidence is limited among women does not imply that women are protected from the dangerous interactions of smoking and occupational exposures. Pregnancy, Infant Health, and Reproduction Scientific studies encompassing various races and ethnic groups, cultures and countries, involving hundreds of thousands of pregnancies, have shown that cigarette smoking during pregnancy significantly affects the unborn fetus and the newborn baby. These damaging effects have been repeatedly shown to operate independently of all other factors that influ- ence the outcome of pregnancy. The effects are increased by heavier smoking and are reduced if a woman stops smoking during pregnancy. Numerous toxic substances in cigarette smoke, such as nicotine and hydrogen cyanide, cross the placenta to affect the fetus directly. The carbon monoxide from cigarette smoke is transported into the fetal blood and deprives the growing baby of oxygen. Fetal growth is directly retarded. The resulting re- duction in fetal weight and size has many unfortunate conse- quences. Women who smoke cigarettes during pregnancy have more spontaneous abortions, and a greater incidence of bleed- ing during pregnancy, premature and prolonged rupture of am- vii niotic membranes, abruptio placentae and placenta previa. Women who smoke cigarettes during pregnancy have more fetal and neonatal deaths than nonsmoking pregnant women. A rela- tion between maternal smoking and Sudden Infant Death Syn- drome has now been established. The direct harmful effects of smoking on the fetus have long term consequences. Children of mothers who smoked during pregnancy lag measurably in physical growth; there may also be effects on behavior and cognitive development. The extent of these deficiencies increases with the number of cigaret- tes smoked. The damaging effects of maternal smoking on infants are not restricted to pregnancy. Nicotine, a known poison, is found in the breast milk of smoking mothers. Children whose parents smoke cigarettes have more respiratory infections and more hospitalizations in the first year of life. Women who smoke cigarettes have more than three times the risk of dying of stroke due to subarachnoid hemorrhage, and as much as two times the risk of dying of heart attack in compari- son to nonsmoking women. The use of oral contraceptives in addition to smoking, however, causes a markedly increased risk, including a 22-fold increase in the risk of subarachnoid hemor- rhagic stroke and a 20-fold increase in heart attack in heavy smokers. Why Do Women Smoke? Cigarette consumption in this country is now declining. An- nual per capita consumption has decreased from 4,258 in 1965 to an estimated 3,900 in 1979. From 1965 to 1979, the proportion of adult male cigarette smokers declined from 51 to 37 percent. Not only have millions of men quit smoking, but the rate of initia- tion of smoking among adolescent males has now slowed. From 1965 to 1976, the proportion of adult women cigarette smokers remained virtually unchanged at 32 to 33 percent. Since 1976, however, the proportion of adult women cigarette smokers appears to have declined to 28 percent. Although adult women are now beginning to quit smoking at rates comparable to adult men, the rate of initiation of smoking among younger women has not declined. This report documents numerous differences by sex in the perceived role of cigarette smoking, in attitudes toward health and lifestyle, and in methods of coping with stress, anger, and boredom. Yet the significance of these differences, and their relation to differences in smoking patterns, remains poorly un- derstood. **. Vlll Although it is frequently observed that women in organized smoking cessation programs have more severe withdrawal symptoms and lower rates of successful quitting than men, these observations have not been systematically confirmed for the general population. In the past, women may have attempted to quit or succeeded in quitting smoking less frequently than men. The recent decline in the proportion of women smokers, however, suggests that women's attempted and successful quit- ting rates have now increased. Although weight gain is a frequently cited consequence of quitting smoking, the association of weight gain with cessation of smoking has not been the subject of sufficient scrutiny. Con- trolled studies with careful measurement on representative populations of women do not exist. The impact of the fear of weight gain after quitting has not been adequately examined. If weight gain does result from cessation of smoking, its exact mechanism must be determined. Even more problematic are marked differences by sex in the distribution of smoking prevalence by occupation. Men with ad- vanced education and professional occupations have taken the lead in quitting smoking, but women in administrative and managerial positions have relatively high smoking prevalence rates. Although 20 percent or fewer male physicians smoke, the proportions of cigarette smokers among women health profes- sionals, especially nurses and psychologists, remain disturb- ingly high. Recent changes in smoking prevalence among black women and men have paralleled those of the general population. From 1965 to 1979, the proportion of black women cigarette smokers declined from 34 to 29 percent, while the proportion of black men smokers declined from 61 to 42 percent. However, differences by race in the onset, maintenance, and cessation of smoking have not been adequately explored. Little is known about cigarette smoking among other ethnic and minority groups. Adolescent Smoking The health consequences of smoking evolve over a lifetime. Evidence continues to accumulate, for example, that cigarette smoking produces measurable lung changes in adolescence and young adulthood. Young cigarette smokers of both sexes show more evidence of small airway dysfunction, and a higher preva- lence of cough, wheezing, phlegm production, and other respira- tory symptoms. The health damage due to cigarette smoking increases when an individual begins regular smoking earlier in life. Yet, as this report documents, the average age of onset of ix regular smoking among women has continuously declined dur- ing the last 50 years, and continues to decline. According to a recent survey by the National Institute of Education, cigarette smoking among adolescent girls now ex- ceeds that among adolescent boys. In the 17-19 year age group, there are almost 5 female cigarette smokers for every 4 male cigarette smokers. The causes of this inversion are far from clear. We do not yet understand the signal events in the initia- tion of smoking among young women. It is possible that parents set examples concerning lifestyle, health attitude, and risk- taking much earlier in childhood. The beginning of junior high school or entrance into the work force may be equally critical events. We do not know enough about an adolescent's sense of competence and self-mastery, and how these roles differ among women and men. Although smoking patterns among girls corre- late with parental, peer and sibling smoking habits, educational level, type of school curriculum, academic performance, socioeconomic status, and other forms of substance abuse, the practical significance of these empirical correlations is unclear. Women and the Changing Cigarette As this report documents, the proportion of men and women smokers using brands with lowered "tar" and nicotine con- tinues to grow. Adolescents of both sexes have followed this trend, to the point where nonfilter cigarettes are relatively rare among young adults. Although the preponderance of scientific evidence continues to suggest that cigarettes with lower "tar" and nicotine are less hazardous, four serious warnings are in order. First, the reported "tar" and nicotine deliveries of cigarettes are standardized machine measurements. They do not neces- sarily represent the smoker's actual intake of these substances. Evidence is now mounting that individuals who switch to cigarettes with lowered "tar" and nicotine inhale more deeply, smoke a greater proportion of their cigarettes, and in some cases smoke more cigarettes. Second, "tar" and nicotine are not the only dangerous chemi- cal components of cigarette smoke. Many conventional filter cigarettes, in fact, may deliver more carbon monoxide than non- filter cigarettes. Third, it has not been established that lower "tar" and nicotine cigarettes have less harmful effects on the unborn fetus and baby; on women and men at high risk for developing coronary heart disease, such as those with elevated cholesterol or high blood pressure; or on workers with adverse occupational X exposures. It has not been established that switching to a lower "tar" and nicotine cigarette has any salutary effect on indi- viduals who already have smoking-related illnesses, such as coronary heart disease, chronic bronchitis, and emphysema. Fourth, even the lowest yield cigarettes present health hazards for both women and men that are very much higher than smoking no cigarettes at all. The single most effective way for both women and men smok- ers to reduce the hazards associated with cigarettes is to quit smoking. As this report demonstrates, little is known about the effects of these product changes on the initiation, maintenance and cessation of smoking, particularly among women. It has not been determined whether the availability of cigarettes with lowered "tar" and nicotine has made it easier for young women to experiment with and besome addicted to cigarettes. It is not known whether smokers of the lowest yield cigarettes are more or less likely to attempt to quit, or to succeed in quitting, than smokers of conventional filtertip or nonfilter cigarettes. The extent to which the act of switching to a lower "tar" cigarette serves as a substitute for quitting may differ among women and men. Public Health Responsibilities This report, which includes data compiled by individuals from both inside and outside the Government, has confirmed in every way the judgement of the World Health Organization that there can no longer be any doubt among informed people that cigarette smoking is a major and removable cause of ill health and premature death. Each individual woman must make her own decision about this significant health issue. Secretary Harris has noted that the role of the Government, and all responsible health profes- sionals, is to assure that this decision is an informed one. In issuing this report, we hope to help the public health community accomplish this purpose. Julius B. Richmond, M.D. Assistant Secretary for Health and Surgeon General xi ACKNOWLEDGEMENTS This report was prepared by agencies of the U.S. Department of Health, Education, and Welfare under the general editorship of the Office on Smoking and Health, John M. Pinney, Director. Consulting scientific editors were David M. Burns, M.D., As- sistant Clinical Professor of Medicine, Pulmonary Division, University of California at San Diego, San Diego, California, and John H. Holbrook, M.D., Associate Professor of Internal Medicine, University of Utah Medical School, Salt Lake City, Utah. Contributing scientific editors were Joanne Luoto, M.D., M.P.H., Medical Officer, Office on Smoking and Health, Rockville, Maryland, and Kelley L. Phillips, M.D., M.P.H., Ex- pert Consultant, Office on Smoking and Health, Rockville, Maryland. Introduction and Summary Office on Smoking and Health Patterns of Cigarette Smoking Office on Smoking and Health Jeffrey E. Harris, M.D., Ph.D., Associate Professor, Depart- ment of Economics, Massachusetts Institute of Technology, Cambridge, Massachusetts; Clinical Associate, Medical Serv- ices, Massachusetts General Hospital, Boston, Mas- sachusetts. Mortality National Heart, Lung, and Blood Institute Eugene Rogot, M.A., Division of Heart and Vascular Diseases, National Heart, Lung, and Blood Institute, National Insti- tutes of Health, Bethesda, Maryland. Thomas J. Thorn, Division of Heart and Vascular Diseases, National Heart, Lung, and Blood Institute, National Insti- tutes of Health, Bethesda, Maryland. Morbidity National Center for Health Statistics Ronald W. Wilson, M.A., Chief, Health Status and Demo- graphic Analysis Branch, Division of Analysis, National Cen- ter for Health Statistics, Hyattsville, Maryland. Cardiovascular Diseases National Heart, Lung, and Blood Institute G. C. McMillan, M.D., Ph.D., Associate Director for Etiology of Arteriosclerosis and Hypertension, Division of Heart and Vascular Diseases, National Heart, Lung, and Blood Insti- tute, National Institutes of Health, Bethesda, Maryland. . . . x111 Cancer National Cancer Institute Jesse L. Steinfeld, M.D., Dean, School of Medicine, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia. Non-Neoplastic Bronchopulmonary Diseases National Heart, Lung, and Blood Institute Richard A. Bordow, M.D., Associate Director of Respiratory Medicine, Brookside Hospital, San Pablo, California. Claude J. M. Lenfant, M.D., Director, Division of Lung Dis- eases, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. Barbara Marzetta Liu, S.M., Division of Lung Diseases, Na- tional Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. Eric R. Jurrus, Ph.D., Division of Lung Diseases, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. Interaction Between Smoking and Occupational Exposures National Institute of Occupational Safety and Health Jeanne M. Stellman, Ph.D., Associate Professor, Columbia University, School of Public Health, New York, New York. Steven D. Stellman, Ph.D., Assistant Vice-President for Epidemiology, American Cancer Society, New York, New York. Pregnancy and Infant Health National Institute of Child Health and Human Development Eileen G. Hasselmeyer, Ph.D., R.N., Associate Director for Scientific Review, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Mary B. Meyer, Sc.M., Associate Professor of Epidemiology, Johns Hopkins University, School of Hygiene and Public Health, Baltimore, Maryland. Lawrence D. Longo, M.D., Professor of Physiology and of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, California. Donald R. Mattison, M.D., Medical Officer, Pregnancy Re- search Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Peptic Ulcer Disease National Institute of Arthritis, Metabolism and Digestive Diseases Travis E. Solomon, M.D., Ph.D., Center for Ulcer Research xiv and Education, Veterans Administration Wadsworth Medical Center, and University of California, Los Angeles School of Medicine, Los Angeles, California. Janet D. Elashoff, Ph.D., Center for Ulcer Research and Edu- cation, Veterans Administration Wadsworth Medical Center and University of California, Los Angeles School of Medicine, Los Angeles, California. Interactions of Smoking with Drugs, Food Constituents, and Responses to Diagnostic Tests Food and Drug Administration Cheryl Fossum Graham, M.D., Division of Drug Experience, Office of Biometrics and Epidemiology, Bureau of Drugs, Food and Drug Administration, Rockville, Maryland. Psychosocial and Behavioral Aspects of Smoking in Women National Institute on Drug Abuse and National Institute of Child Health and Human Development Initiation Ellen R. Gritz, Ph.D., Research Psychologist, Veterans Ad- ministration Medical Center, Brentwood, and Associate Re- search Psychologist, Department of Psychiatry and Biobehavioral Sciences, School of Medicine, University of California, Los Angeles, California. Ann F. Brunswick, Ph.D., Senior Research Associate (Public Health, Sociomedical Sciences), Center for Sociocultural Re- search on Drug Use, Columbia University, New York, New York. Maintenance and Cessation Karen L. Bierman, M.A., Department of Psycholo,ay, Univer- sity of California, Los Angeles, California. Ellen R. Gritz, Ph.D., Research Psychologist, Veterans Ad- ministration Medical Center, Brentwood, and Associate Re- search Psychologist, Department of Psychiatry and Biobehavioral Sciences, School of Medicine, University of California, Los Angeles, California. The editors acknowledge with gratitude the many distin- guished scientists, physicians, and others who assisted in the preparation of this report by coordinating manuscript prepara- tion, contributing critical reviews of the manuscripts or helping in other ways. Elvin E. Adams, M.D., M.P.H., Chairman, Texas Interagency Council on Smoking and Health, Practicing Internal Medicine, Fort Worth, Texas. Josephine D. Arasteh, Ph.D., Health Scientist Administrator, xv Human Learning and Behavior Branch, Center for Research for Mothers and Children, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Lester Breslow, M.D., M.P.H., Dean, School of Public Health, University of California at Los Angeles, Los Angeles, Califor- nia. A. Sonia Buist, M.D., Associate Professor of Medicine and Physiology, University of Oregon Health Sciences Center, Portland, Oregon. David M. Burns, M.D., Assistant Clinical Professor of Medicine, Pulmonary Division, University of California at San Diego, San Diego, California. Thomas C. Chalmers, M.D., President and Dean, Mount Sinai Medical Center, New York, New York. Florence L. Denmark, Ph.D., Professor of Psychology, Hunter College of the City University of New York, and President of the American Psychological Association, New York, New York. Robert M. Donaldson, Jr., M.D., Chief, Medical Services, Westhaven Veterans Hospital, and Vice-Chairman, Depart- ment of Internal Medicin.e, Yale University School of Medicine, New Haven, Connecticut. Joseph T. Doyle, M.D., Professor of Medicine and Head, Divi- sion of Cardiology of the Department of Medicine, Albany Medical College of Union University, Albany, New York. Elizabeth M. Earley, Ph.D., Chief, Section of Cytogenetics, Division of Pathology, Bureau of Biologics, Food and Drug Administration, Rockville, Maryland. Bernard H. Ellis, Jr., Program Director for Smoking and Oc- cupational Activities, Office of Cancer Communications, Na- tional Cancer Institute, National Institutes of Health, Bethesda, Maryland. Diane Fink, M.D., Associate Director, National Cancer Insti- tute, and Coordinator, Smoking, Cancer, and Health Program, National Institutes of Health, Bethesda, Maryland. Harold E. Fox, M.D., Associate Professor of Clinical Obstetrics and Gynecology, Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University, and Medical Director, Western and Upper Manhattan Perinatal Network, New York, New York. Joseph H. Gainer, D.V.M., Veterinary Medical Officer, Divi- sion of Veterinary Medical Research, Bureau of Veterinary Medicine, Food and Drug Administration, Beltsville, Mary- land. Stanley N. Gershoff, Ph.D., Director, Nutrition Institute and xvi Chairman, Graduate Department of Nutrition, Tufts Univer- sity, Medford, Massachusetts. Mary E. Guinan, M.D., Clinical Research Investigator, Clini- cal Studies Section, Venereal Disease Control Division, Cen- ter for Disease Control, Atlanta, Georgia. Sharon M. Hall, Ph.D., Assistant Professor in Residence, Uni- versity of California at San Francisco, Langley Porter Psy- chiatric Institute, San Francisco, California. Jane Halpern, M.D., Assistant Secretary for Policy Evalua- tion and Research, Office of Health and Disability, United States Department of Labor, Washington, D.C. Beatrix A. Hamburg, M.D., Senior Research Psychiatrist, Laboratory of Developmental Psychology, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland. Virginia G. Harris, M.D., Director, Maternal and Child Health, Onondaga County Health Department, Syracuse, New York. John H. Holbrook, M.D., Associate Professor of Internal Medicine, University of Utah Medical School, Salt Lake City, Utah. L. Stanley James, M.D., Professor of Pediatrics, and of Obstet- rics and Gynecology, and Director, Division of Perinatal Medicine, College of Physicians and Surgeons, Columbia Uni- versity, New York, New York. Hershel Jick, M.D., Boston Collaborative Drug Surveillance Program, Boston University Medical Center, Waltham, Mas- sachusetts. Reese T. Jones, M.D., Professor of Psychiatry, Department of Psychiatry, University of California at San Francisco, Langley Porter Psychiatric Institute, San Francisco, California. Philip Kimbel, M.D., Chairman, Department of Medicine, Graduate Hospital, Philadelphia, Pennsylvania. Jan W. Kuzma, Ph.D., Chairman and Professor of Biostatis- tics, Department of Biostatistics and Epidemiology, Loma Linda University, Loma Linda, California. Abraham Lilienfeld, M.D., M.P.H., D.Sc., University Distin- guished Service Professor, Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland. Harold A. Menkes, M.D., Associate Professor of Medicine and Environmental Health Sciences, Department of Medicine, Johns Hopkins University, Baltimore, Maryland. Kenneth Moser, M.D., Professor of Medicine and Director, Pulmonary Division, University of California at San Diego, San Diego, California. Mariquita Mullan, B.S.N., M.P.H., Special Assistant to the Di- xvii rector, National Institute of Occupational Safety and Health, Center for Disease Control, Rockville, Maryland. Janyce E. Notopoulos, Program Analyst, Office of Planning and Evaluation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Albert Oberman, M.D., Director, Division of Preventive Medicine, University of Alabama in Birmingham Medical Center, Birmingham, Alabama. Ralph S. Paffenbarger, M.D., D.R.P.H., Professor of Epidemiology, Stanford University, School of Medicine, Stan- ford, California, and Adjunct Professor of Epidemiology at the University of California, School of Public Health, Berkeley, California. Richard Peto, M.D., Radcliff Clinic, Oxford University, Ox- ford, England. Malcolm C. Pike, Ph.D., Professor, Community and Family Medicine, School of Medicine, University of Southern Califor- nia at Los Angeles, Los Angeles, California. Ovide F. Pomerleau, Ph.D., Professor of Psychology and Psy- chiatry, University of Connecticut, School of Medicine, Far- mington, Connecticut. Phil1 H. Price, M.D., Medical Officer, Metabolic Products Branch, Division of Metabolism and Endocrine Drugs, Bureau of Drugs, Food and Drug Administration, Rockville, Maryland. Dorothy P. Rice, Director, National Center for Health Statis- tics, Office of the Assistant Secretary for Health, Hyattsville, Maryland. Anthony Robbins, M.D., Director, National Institute of Occu- pational Safety and Health, Center for Disease Control, Rockville, Maryland. Judith B. Rooks, C.N.M., M.P.H., M.S., Office of the Assistant Secretary for Health, Washington, D.C. Harold P. Roth, M.D., Associate Director for Digestive Dis- eases and Nutrition, National Institute of Arthritis, Metabolism, and Digestive Diseases, National Institutes of Health, Bethesda, Maryland. Philip Sapir, Special Assistant to the Director for Behavioral and Social Sciences and Chief, Human Learning and Behavior Branch, Center for Research for Mothers and Children, Na- tional Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Marvin A. Schniederman, Ph.D., Associate Director for Sci- ence Policy, National Cancer Institute, National Institutes of Health, Bethesda, Maryland. . . . Xvlll Irving J. Selikoff, M.D., Professor of Community Medicine and Professor of Medicine, and Director of Environmental Sci- ences Laboratory, Mount Sinai Medical Center, New York, New York. S. I. Shibko, Ph.D., Chief, Contaminants and Natural Toxic- ants Branch, Division of Toxicology, Bureau of Foods, Food and Drug Administration, Washington, D.C. Jeremiah Stamler, M.D., Chairman, Department of Commu- nity Health and Preventive Medicine, Northwestern Univer- sity Medical School, Chicago, Illinois. John E. Vanderveen, Ph.D., Director, Division of Nutrition, Bureau of Foods, Food and Drug Administration, Washington, D.C. Eve Weinblatt, Assistant Director for Research, Department of Research and Statistics, Health Insurance Plan of Greater New York, New York, New York. Samuel S. C. Yen, M.D., Professor and Chairman, Department of Reproductive Medicine, University of California, San Di- ego, LaJolla, California. The editors also acknowledge the help of the following staff who among others assisted in the preparation of the report. John L. Bagrosky, Associate Director for Program Opera- tions, Office on Smoking and Health, Rockville, Maryland. Jacqueline 0. Blandford, Clerk-Typist, Office on Smoking and Health, Rockville, Maryland. Betty Budd, Secretary, Office on Smoking and Health, Rockville, Maryland. John F. Hardesty, Jr., Public Information Officer, Office on Smoking and Health, Rockville, Maryland. Patricia E. Healy, Technical Information Clerk, Office on Smoking and Health, Rockville, Maryland. Robert S. Hutchings, Associate Director for Information and Program Development, Office on Smoking and Health, Rockville, Maryland. &Margaret E. Ketterman, Secretary, Office on Smoking and Health, Rockville, Maryland. Richard A. La SCO, Ph.D., Bureau of Health Education, Center for Disease Control, Atlanta, Georgia. Joanne Luoto, M.D., M.P.H., Medical Officer, Office on Smok- ing and Health, Rockville, Maryland. Judith L. Mullaney, M.L.S., Tephnical Information Specialist, Office on Smoking and Health, Rockville, Maryland. Marjorie L. Olson, Secretary, Office on Smoking and Health, Rockville, Maryland. xix Kelley L. Phillips, M.D., M.P.H., Expert Consultant, Office on Smoking and Health, Rockville, Maryland. David L. Pitts, Public Health Advisor, Operations Branch, Nutrition Division, Bureau of Smallpox Eradication, Center for Disease Control, Atlanta, Georgia. Donald R. Shopland, Technical Information Officer, Office on Smoking and Health, Rockville, Maryland. Linda R. Spiegelman, Administrative Assistant, Office on I Smoking and Health, Rockville, Maryland. Carol M. Sussman, Technical Publication Writer/Editor, Of- fice on Smoking and Health, Rockville, Maryland. Ronald G. Thomas, Public Health Analyst, Office on Smoking and Health, Rockville, Maryland. Selwyn M. Waingrow, Public Health Analyst, Office on Smok- ing and Health, Rockville, Maryland. Ann E. Wessel, Public Health Analyst, Office on Smoking and Health, Rockville, Maryland. Carole L. Winn, Assistant Chief, Clinical Chemistry Stand- ardization Section, Clinical Chemistry Division, Metabolic Biochemistry Branch, Bureau of Laboratories, Center for Disease Control, Atlanta, Georgia. xx TABLE OF CONTENTS INTRODUCTION AND SUMMARY . . . . . . . . . . . . . . . . . . . . . 1 PART I PATTERNS OF CIGARETTE SMOKING . . . . . . . . . . . . . . . . 15 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 The Rise of Cigarette Smoking: 1900-1950 . . . . . , . . . . . 17 The Emergence of Filtertip Cigarettes: 1951-1963 . . 21 Increasing Public Health Awareness: 1964-1979 . . . . . 21 Exposure to Cigarette Smoking Among Successive Birth Cohorts . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Cigarette Smoking Among Young Women . . . . . . . . . . . 33 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 PART II BIOMEDICAL ASPECTS OF SMOKING MORTALITY ............................................ 44 Introduction and Background ....................... 45 Mortality Trends .................................... 45 Epidemiological Studies ............................. 46 The American Cancer Society 25-State Study ................................. 47 The Swedish Study .............................. 51 The Canadian Veterans Study ................... 51 Japanese Study of 29 Health Districts ........... 51 The British Doctors Study ....................... 51 The Framingham Heart Study .................. 52 The British-Norwegian Migrant Study ................................. 52 Overall Mortality for Females-Cigarette Smokers Versus Nonsmokers ............................... 53 Mortality Ratios ................................. 53 Amount Smoked and Age ........................ 54 Duration of Smoking ............................ 57 Age Began Smoking ............................. 58 Inhalation ....................................... 59 "Tar" and Nicotine Content of Cigarettes ..................................... 59 xxi Comments ........................................... Summary ............................................ References .......................................... MORBIDITY ............................................ Days Lost from Work ................................ Limitation of Activity ............................... Cigarette Smoking and Occupation .................. Summary ............................................ References .......................................... CARDIOVASCULAR DISEASES ........................ Introduction ......................................... Mortality Rates ..................................... Atherosclerosis ...................................... RiskFactors ......................................... The Effect of Smoking ............................... Atherosclerosis .................................. Coronary Heart Disease ......................... Cessation of Smoking and "Tar" and Nicotine Content of Cigarettes ................................. Angina Pectoris ................................. Cerebrovascular Disease ......................... Arteriosclerotic Peripheral Vascular Disease .............................. Aortic Aneurysm ................................ Hypertension .................................... Venous Thrombosis .............................. High-Density Lipoprotein ........................ Oral Contraceptive Use, Smoking, and Cardiovascular Disease ............................ 61 61 62 65 67 68 69 70 75 77 79 79 84 86 86 86 88 92 93 93 95 96 96 97 98 98 Carbon Monoxide .................................... 101 Comment ............................................ 101 Summary ............................................ 102 References .......................................... 103 CANCER ................................................ 107 Introduction ......................................... 109 Lung ................................................ 111 Geographic Differences .......................... 116 Smoking Patterns Among Women ............... 117 Cessation of Smoking ............................ 120 Experimental Carcinogensis ..................... 121 Larynx .............................................. 121 Oral ................................................. 122 Esophagus ........................................... 123 xxii Urinary Bladder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Kidney . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 Pancreas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Non-neoplastic Bronchopulmonary Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Smoking and Respiratory Mortality . . . . . . . . . . . . . . . . . 137 Smoking and the Epidemiology and Pathology of Cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Smoking and Respiratory Morbidity . . . . . . . . . . . . . . . . . 146 Smoking and Pulmonary Function . . . . . . . . . . . . . . . . . . . 156 Smoking and "Early" Functional Abnormalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 Smoking and Ventilatory Function . . . . . . . . . . . . . . 160 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 Interaction Between Smoking and Occupational Exposures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Smoking Patterns in Women . . . . . . . . . . . , . . . . . . . . . . . . , 172 Patterns of Employment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 The Reproductive Role . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Specific Interactions Between Occupational Exposure and Smoking . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Asbestos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Cotton Dust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 PREGNANCY AND INFANT HEALTH . . . . . . . . . . . . . . . . . 189 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 Smoking, Birth Weight, and Fetal Growth . . . . . . . . . . . 191 Placental Ratios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 Gestation and Fetal Growth . . . . . . . . . . . . . . . . . . . . . 195 Long-Term Growth and Development . . . . . . . . . . . . 196 Role of Maternal Weight Gain . . . . . . . . . . . . . . . . . . . 202 Smoking, Fetal and Infant Mortality, and Morbidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 Spontaneous Abortion . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 Congential Malformations . . . . . . . . . . . . . . . . . . . . , . , 207 Perinatal Mortality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 CauseofDeath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 Complications of Pregnancy and Labor . . . . . . . . . . . . . . 214 . . . xx111 Preeclampsia .................................... LII Preterm Delivery, Pregnancy Complications, and Perinatal Mortality by Gestation ........................ 217 Long-Term Morbidity and Mortality ................. 221 Sudden Infant Death Syndrome ................. 225 Mechanisms ......................................... 226 Experimental Studies ............................... 229 Tobacco Smoke ................................... 229 Nicotine ......................................... 229 Carbon Monoxide ................................ 231 Polycyclic Aromatic Hydrocarbons ............... 233 Other Components ............................... 234 Fertility ............................................. 235 Smoking and Reproduction in Women ........... 235 Smoking and Age of Menopause ................. 236 Smoking and Reproduction in Men .............. 236 Fertilization and Conceptus Transport ..................................... 237 Summary ............................................ 238 References .......................................... 239 PEPTIC ULCER DISEASE ............................. 251 Summary ............................................ 254 References .......................................... 254 INTERACTIONS OF SMOKING WITH DRUGS, FOOD CONSTITUENTS, AND RESPONSES TO DIAGNOSTIC TESTS .............................. 259 Women Smokers and Nonsmokers and Drug Consumption Patterns ....................... 259 Altered Clinical Response to Drug Therapy by Smokers as Compared to Nonsmokers .......... 261 Oral Contraceptives and Smoking ................... 262 Alterations in Normal Clinical Laboratory Values in Women Smokers ......................... 263 The Influence of Smoking on the Nutritional Needs of Women ....................... 264 Summary ............................................ 265 References .......................................... 265 PART III PSYCHOSOCIAL AND BEHAVIORAL ASPECTS OF SMOKING IN WOMEN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271 xxiv Initiation of Smoking in Adolescent Girls . . . . . . . . . . . . 271 Concepts of Adolescent Behavior . . . . . . . . . . . . . . . . . 272 Prevalence and Patterns of Adolescent Cigarette Use . . . . . . . . . . . . . . . . . . . . . . 273 Prevalence . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . 273 Age at Initiation of Smoking . . . . . . . . . . . . . . . . 275 Number of Cigarettes Smoked . . . . . . . . . . . . . . . 277 Type of Cigarette Smoked . . . . . . . . . . . . . . . . . . . 278 Smoking Cessation . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Smoking Prevalence and Ethnicity . . . . . . . . . . 280 Alcohol and Marihuana Use . . . . . . . . . . . . . . . . . 280 Demographic and Psychosocial Correlates of Smoking in Adolescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 Socioeconomic Influences . . . . . . . . . . . . . . . . . . . . 281 Family Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282 Smoking Among Parents and Siblings . . . . . . . 282 Peer Group Influence . . . . . . . . . . . . . . . . . . . . . . . . 284 Scholastic Achievement and Aspirations . . . . . 285 Dynamic/Personality Factors . . . . . . . . . . . . . . . . 286 Prediction of Future Smoking Behavior . . . . . 288 Prevention of Smoking and Considerations for Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Prevention of the Initiation of Smoking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Research Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 Maintenance of Smoking Behavior ..,............... 293 Patterns of Cigarette Smoking . . . . . . . . . . . . . . . . . . . 293 Smoking Prevalence and Ethnicity . . , . . . . . . . 296 Pharmacological Effects of Smoking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Nicotine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Peripheral Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Central Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 A Possible Role for Nicotine in Smoking Maintenance . . . . ..**.a........... 298 Differences in Nicotine Metabolism . . . . . . . . . . 300 Smoking and Stimulation Effects . . . . . . . . . . . . . . . . 300 Smoking Cessation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302 Demographics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Education . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . 303 Income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Occupation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Psychology of Changing Smoking Habits . . . . . . . . 305 xxv Treatment Studies ............................... 306 The Smoking Withdrawal Syndrome ............. 315 Smoking and Weight Control .................... 315 Treatment Recommendations .................... 319 Conclusions ...................................... 321 Dissemination of Information About Smoking ....... 321 Health Attitudes and Behaviors ................. 321 Sources of Information .......................... 322 Health Care Providers ....................... 322 Educators ................................... 324 Peer Group .................................. 324 Family ...................................... 325 Media: Television, Radio, Film, Newspapers, Magazines ................... 325 Advertising .................................. 325 The Failure to Disseminate Information ................................... 327 Stress at Work ....................................... 327 Smoking Habits of Health Professionals ............. 329 Physicians ....................................... 329 Psychologists .................................... 332 Nurses .......................................... 333 The Pregnant Smoker-A Special Target ............ 336 Sources of Information .......................... 336 Physician Advice ............................ 337 Prevalence of Smoking and Quitting During Pregnancy ............................. 340 Psychosocial Factors in Quitting ................. 344 Recommendations ............................... 345 Summary ............................................ 346 References .......................................... 347 xxvi INTRODUCTION AND SUMMARY. INTRQDUCTION AND SUMMAFtY The 1980 Report on the Health Consequences of Smoking fo- cuses upon the evidence relating cigarette smoking to health effects in women. It is not presented as a detailed discussion of the entire range of effects of smoking on health. Such a detailed review of all existing evidence can be found in the 1979 Report of the Surgeon General on Smoking and Health. Instead, this volume on smoking and women's health is offered as a review and reappraisal of smoking and major health relationships spe- cifically in women. It is intended to serve the medical commu- nity as a unified source of existing scientific evidence about health effects of smoking cigarettes for women. As an examina- tion of current knowledge, it will logically lend itself to applica- tion in both the personal and public health arenas. Its content is the work of numerous scientists within the De- partment of aealth, Education, and Welfare, as well as scien- tific experts outside that organization. This volume examines the major issues relating tobacco use -to women's health including trends in consumption, the biomed- ical evidence of the health effects of cigarette usage by women, and determinants of smoking initiation, maintenance, and ces- sation. This section summarizes the principal findings of this report. lt is hoped that the entire volume will serve to highlight the established risks of smoking for women and their children, as well as to define the areas in need of further investigation. PM.ems of Cigarette Smoking 1. Women have differed from men in their historical onset of widespread cigarette use, in the rate of diffusion of smoking among each new birth cohort, in their intensity of cigarette smoking and their use of various types of cigarettes. 2. Men took up cigarette smoking rapidly at the beginning of the twentieth century, especially during World War I. Cigar- ettes rapidly replaced other forms of tobacco. BY 1925 , approximately 50 percent of adult males were cigar@tte smokers. Smoking among men accelerated rapidly during World War II By 1950, the prevalence of cigarette use among men~approached 70 percent in some urban areas. 3. The onset of widespread cigarette use among women `qged behind that of men by 25 to 30 years. The proportion of o dult women smoking cigarettes did not exceed one-quarter unti1 the onset of World War II. `. Between 1951 and 1963, increasing proportions of women 3 and men smokers converted to filtertip cigarettes. By 1964, 79 percent of adult women smokers and 54 percent of adult men smokers used filter cigarettes. 5. After reaching a peak value of 4,336 in 1963, annual per capita consumption of cigarettes declined in 1964,1968-70, and in the period since 1975. The most recent estimate of 3,900 cigarettes per capita in 1979 is approximately equal to that ob- served in 1952. 6. From 1965 to 1978, the proportion of adult men cigarette smokers declined from 51 to 37 percent. The preliminary esti- mate of adult men's smoking prevalence for 1979 is 36.9 percent. From 1965 to 1976, the proportion of adult women smokers re- mained virtually unchanged at 32 to 33 percent. Since 1976, the proportion of women smokers has declined to below 30 percent. For 1979, the preliminary estimate of adult women's smoking prevalence is 28.2 percent. The overall. smoking prevalence of 32.3 percent for both sexes in 1979 represents the lowest re- corded value in at least 45 years. 7. The proportion of adult smokers attempting to quit smok- ing declined from 1970 to 1975, but increased in 1978-1979. In contrast to past years, the proportions of women and men now attempting to quit smoking, and their reported quitting rates, are indistinguishable. Approximately one in three adult smok- ers now makes a serious attempt to quit smoking during the course of a year. Approximately one in five of those who attempt to quit subsequently succeed. 8. The proportion of adult smokers using lower "tar" and nicotine brands has increased substantially. In 1979,39 percent of adult women smokers and 28 percent of adult men smokers reported primary brands with F.T.C. "tar" delivery less than 15.0 milligrams. It is not known whether smokers of the lowest "tar" cigarettes are more or less likely to attempt to quit smok- ing, or to succeed in quitting, than smokers of conventional fil- tertip or non-filter cigarettes. 9. The average number of cigarettes smoked by women and men current smokers has increased. The relationship of this finding to recent declines in the average F.T.C. "tar" and nicotine deliveries of cigarettes is not well understood. 10. With each successive generation, the smoking character- istics of women and men have become increasingly similar. 11. Among women, the average age of onset of regular smok- ing progressively declined with each successive birth cohort- from 35 years of age for those born before 1900, to 16 years of age among those born 1951 to 1960. The average age of onset of regular smoking among young women is now virtually identical to that of young men. 4 12. Maximum smoking prevalence rates have declined sub- stantially in recent birth cohorts of men. Men born 1931 to 1940 reached a peak smoking proportion of 61 percent during 1960- 62, while men born 1941 to 1950 reached a peak smoking propor- tion of 58 percent in 1968-69. Men born 1951 to 1960 reached a peak smoking proportion of 40 percent in 1976. Among recent cohorts of women, peak smoking prevalence rates have declined to a much smaller extent. Women born 1931 to 1940 reached a peak smoking proportion of 45 percent in 1966-68, while women born 1941 to 1950 reached a peak smoking proportion of 41 per- cent in 1970-73. Women born 1951 to 1960 reached a peak smok- ing proportion of 38 percent in 1976. Among the generation born 1951 to 1960, the porportions of women and men smoking cigarettes are now virtually identical. 13. The proportions of women and men smokers in each age group have declined. Among those born before 1951, this decline in smoking prevalence resulted mainly from smoking cessation. By contrast, the observed decline in smoking prevalence among younger men born 1951 to 1960 has resulted from both smoking cessation and a lower rate of smoking initiation. This decline in the rate of onset of smoking among young men has not been observed for young women. 14. Recent survey data on adolescent smoking habits reveal that by ages 17 to 19, smoking prevalence among women ex- ceeds that of men. This finding supports the conclusion that the rate of initiation of smoking among young men- but not that of young women-is declining. The future cigarette use of the youngest generations of women is uncertain. 15. With each successive birth cohort, the accumulated years of cigarette smoking per woman has progressively approached the accumulated years of cigarette smoking per man. Each suc- cessive birth cohort has also experienced progressively smaller sex differences in the fraction of lifetime years of smoking that represents filtertip cigarette use. 16. Among men born during this century, each successive birth cohort has thus far experienced fewer cumulative years of cigarette smoking, higher proportionate exposure to filtertip cigarettes, and lower smoking prevalence rates. This relation- ship between birth date and cigarette smoke exposure does not hold for women. Women born 1921 to 1940 have experienced substantially higher smoking prevalence rates than earlier generations. Unless they quit smoking in substantial numbers, these women, currently aged 40 to 59, will surpass older women in total years of cigarette smoking per capita, the total years of nonfilter cigarette smoking per capita, and in the total number of cigarettes smoked. The health consequences of this enhanced 5 exposure to cigarette smoke among women are likely to be more prominent in the coming decades. Mortality 1. The mortality ratio for women who smoke cigarettes is about 1.2 or 1.3. 2. Mortality ratios for women increase with the amount smoked. In the largest prospective study the mortality ratio was 1.63 for the two-pack-a-day smoker as compared to nonsmokers. 3. Mortality ratios are generally proportional to the duration of cigarette smoking; the longer a woman smokes, the greater the excess risk of dying. 4. Mortality ratios tend to be higher for those women who begin smoking at a young age as compared to those who begin smoking later. 5. Mortality ratios are higher for those women who report they inhale smoke than for those who do not inhale. 6. Mortality ratios for women tend to increase with the tar and nicotine content of the cigarette. 7. Mortality ratios for female smokers are somewhat less than for male smokers. This may reflect differences in exposure to cigarette smoke, such as starting smoking later, smoking cigarettes with lower "tar" and nicotine content, and smoking fewer cigarettes per day than men. 8. Women demonstrate the same dose-response relationships with cigarette smoking as men. An increase in mortality occurs with an increase in number of cigarettes smoked per day, an earlier age of beginning cigarette smoking, a longer duration of smoking, inhalation of cigarette smoke, and a higher tar and nicotine content of the cigarette. Women who have smoking characteristics similar to men may experience mortality rates similar to men. Morbidity The 1979 Report of the Surgeon General summarized the in- formation on smoking and morbidity as follows: 1. In general, female current cigarette smokers report more acute and chronic conditions including chronic bronchitis and/or emphysema, chronic sinusitis, peptic ulcer disease, and arteriosclerotic heart disease, than women who never smoked. 2. There is a dose-response relationship between the number of cigarettes smoked per day and the frequency of reporting for most of the chronic conditions. 6 3. The age-adjusted incidence of acute conditions (e.g., in- fluenza) for women smokers is 20 percent higher for women who had ever smoked than for nonsmokers. Additional data from the Health Interview Survey (HIS) is presented: 1. Currently employed women who smoke cigarettes report more days lost from work due to illness and injury than working women who do not smoke. 2. Limitation of activity is reported more commonly among women under the age of 65 who have ever smoked than among those who never smoked. Cardiovascular Diseases Coronary heart disease is the major cause of death among both males and females in the U.S. population. The 1979 Sur- geon General's Report clearly demonstrated the close associa- tion of cigarette smoking and increased coronary heart disease among males. This report reviews the evidence associating cigarette smoking and cardiovascular disease in women: 1. Coronary heart disease, including acute myocardial infarc- tion and chronic ischemic heart disease, occurs more frequently in women who smoke. In general, cigarette smoking increases the risk by a factor of about two, and in younger women cigarette smoking may increase the risk several fold. 2. Cigarette smoking is a major independent risk factor for coronary heart disease in women; it also acts synergistically with other coronary heart disease risk factors producing a risk greater than the sum of the individual risks. 3. The use of oral contraceptives by women cigarette smokers increases the risk of a myocardial infarction by a factor of ap- Proximately ten. 4. Women who smoke low "tar" and nit-tine cigarettes expe- rience less risk for coronary heart disease than women who smoke high "tar" and nicotine cigarettes, but their risk is still considerably greater than that of nonsmokers. 5. Increased levels of high-density lipoprotein (HDL) are cor- related with a reduced risk for an acute myocardial infarction; women cigarette smokers have decreased levels of HDL. 6. Cigarette smoking is a major, independent risk factor for the development of arteriosclerotic peripheral vascular disease in women. Smoking cessation improves the prognosis of the dis- order and has a favorable impact on vascular patency following reconstructive surgery. 7. Women cigarette smokers experience an increased risk for subarachnoid hemorrhage; the use of both cigarettes and oral 7 contraceptives appears to synergistically increase the risk for subarachnoid hemorrhage. 8. Women who smoke cigarettes may be more likely to de- velop severe or malignant hypertension than nonsmoking women. Cancer 1. Cigarette smoking is causally associated with cancer of the lung, larynx, oral cavity, and esophagus in women as well as in men; it is also associated with kidney cancer in women. 2. Cigarette smoking accounts for 18 percent of all cancers newly diagnosed and 25 percent of all cancer deaths in women. In 1980, 26,500 of the estimated 101,000 deaths, or over one- quarter of the deaths expected from lung cancer, will occur in women. 3. Women cigarette smokers have been reported to have be- tween 2.5 and 5 times greater likelihood of developing lung cancer than nonsmoking women. 4. Among women the risk of developing lung cancer increases with increasing number of cigarettes smoked per day, duration of the smoking habit, depth of inhalation, and tar and nicotine content of the cigarette smoked. The risk is inversely related to the age at which smoking began. 5. A dose-response relationship has been demonstrated be- tween cigarette smoking and cancer of the lung, larynx, oral cavity, and urinary bladder in women. 6. The rise in lung cancer death rates is currently much steeper in women than in men. It is projected that the age ad- justed lung cancer death rate will surpass that of breast cancer in the early 1980s. 7. The rapid increase`in lung cancer rates in women is similar to but steeper than the rise seen in men approximately 25 years earlier. This probably reflects the fact that women first began to smoke in large numbers 25-30 years after the increase in cigarette smoking among men. Thus, neither men nor women are protected from developing lung cancer caused by cigarette smoking. 8. Cigarette smoking has been causally related to all four of the major histologic types of lung cancer in both women and men, including epidermoid, small cell, large cell and adenocar- cinema. 9. The use of filter cigarettes and cigarettes with lower levels of "tar" and nicotine by women is correlated with a lower risk of cancer of the lung and larynx compared to the use of high-"tar" and-nicotine or unfiltered cigarettes. The risk posed by smoking 8 low-"tar" cigarettes, however, is clearly greater than that among females who never smoked. 10. After cessation of cigarette smoking, a woman's risk of developing lung and laryngeal cancer has been shown to drop slowly, equalling that of nonsmokers after lo-15 years. 11. Excessive ingestion of alcohol acts synergistically with cigarette smoking to increase the incidence of oral and laryngeal cancer in women. Non-Neoplastic Bronchopulmonary Diseases 1. Recent statistics indicate a rising death rate due to chronic obstructive lung disease (COLD) among women. The data avail- able demonstrate an excess risk of death from COLD among smoking women over that of nonsmoking women. This excess risk is much greater for heavy smokers than for light smokers. 2. Women's total risk of COLD appears to be somewhat lower than men's, a difference which may be due to differences in prior smoking habits. 3. The prevalence of chronic bronchitis varies directly with cigarette smoking, increasing with the number of cigarettes smoked per day. 4. There is conflicting evidence regarding differences in the prevalence of chronic bronchitis in women and men. Several recent studies suggest that there is no significant difference in the prevalence of chronic bronchitis between male and female smokers. This may be the result, however, of increasingly simi- lar smoking behavior of women and men. 5. The presence of emphysema at autopsy exhibits a dose- response relationship with cigarette smoking during life. 6. There is a close relationship between cigarette smoking and chronic cough or chronic sputum production in women, which increases with total pack-years smoked. 7. Women current smokers have poorer pulmonary function by spirometric testing than do female ex-smokers or nonsmok- ers, a relationship which is dose-related to the number of cigarettes smoked. Interaction Between Smoking ad Occupational Exposures 1. The 1979 Surgeon General's Report identified the ways in which smoking cigarettes may interact with the occupational environment. They include: a) Facilitation of absorption of physical contamination of cigarettes, b) Transformation of workplace chemicals into more toxic substances, 9 c) Addition of the exposure to a toxic constituent of to- bacco smoke to a concurrent exposure to the same con- stituent present in the workplace, d) Addition of a health effect due to environmental expo- sure to a similar health effect due to smoking, el Synergy of exposures, and f) Causation of accidents. 2. Women are entering occupational environments with greater frequency, and thus may be experiencing greater expo- sures to physical and chemical agents. 3. Cohorts of women with a greater prevalence of smoking are currently reaching the ages of maximal disease occurrence, re- placing earlier cohorts with lower cigarette exposures. 4. Physiologic differences in hormonal status between males and females constitute a potential source of differing responses. 5. In the workplace women who are pregnant present a nine-month exposure opportunity, including potential teratogenic and perinatal mortality effects. 6. Concurrent exposure of women to smoking and asbestos resulted in a clear excess of cancer of the lung. 7. Women smokers exposed to cotton dust run a higher risk of developing byssinosis, bronchitic syndromes, and abnormal pulmonary function tests than nonsmoking women. Pregnancy and Infant Health 1. Babies born to women who smoke during pregnancy are, on the average, 200 grams lighter than babies born to comparable nonsmoking women. 2. The relationship between maternal smoking and reduced birth weight is independent of all other factors that influence birth weight including race, parity, maternal size, socioeconomic status, and sex of child; it is also independent of gestational age. 3. There -is a dose-response relationship between maternal smoking and reduced birth weight; the more the woman smokes during pregnancy, the greater the reduction in birth weight. 4. If a woman gives up smoking early during pregnancy, her risk of delivering a low-birth-weight baby approaches that of a nonsmoker. 5. The ratio of placental weight to birth weight increases with increasing levels of maternal smoking, reflecting a considerable decrease in mean birth weight and a slight increase in mean placental mass; this may represent an adaptation to relative fetal hypoxia. 10 6. The pattern of fetal growth retardation that occurs with maternal smoking is a decrease in all dimensions including body length, chest circumference, and head circumference. 7. Maternal smoking during pregnancy may adversely affect the child's long-term growth, intellectual development, and be- havioral characteristics. 8. Maternal smoking during pregnancy exerts a direct growth-retarding effect on the fetus; this effect does not appear to be mediated by reduced maternal appetite, eating or weight gain. 9. The risk of spontaneous abortion, fetal death, and neonatal death increases directly with increasing levels of maternal smoking during pregnancy; interaction of maternal smoking with other factors which increase perinatal mortality may re- sult in an even greater risk. 10. Excess deaths of smokers' infants are found mainly in the coded cause categories of "unknown" and "anoxia" for fetal deaths, and the categories of "prematurity alone" and "respira- tory difficulty" for neonatal deaths; this suggests that the ex- cess deaths are due to problems of the pregnancy, rather than to abnormalities of the fetus or neonate. 11. Increasing levels of maternal smoking result in a highly significant increase in the risk of abruptio placentae, placenta previa, bleeding early or late in pregnancy, premature and pro- longed rupture of membranes, and preterm delivery-all of which carry high risks of perinatal loss. 12. Although there is little effect of maternal smoking on mean gestation, the proportion of fetal deaths and live births that occur before term increases directly with maternal smok- ing level. Up to 14 percent of all preterm deliveries in the United States may be attributable to maternal smoking. 13. The incidence of preeclampsia is decreased among women who smoke during pregnancy; however, if preeclampsia devel- ops in a smoking woman, the risk of perinatal mortality is markedly increased compared to preeclamptic nonsmokers. 14. An infant's risk of developing the "sudden infant death syndrome" is increased by maternal smoking during pregnancy. 15. There are insufficient data to support a judgement on whether maternal and/or paternal cigarette smoking increases ,he risk of congenital malformations. 16. Infants and children born to smoking mothers may expe- -ience more long-term morbidity than those born to non- smoking mothers; however, studies usually cannot distinguish jetween the effects of smoking during pregnancy and the ef- `e&s of the infant's or child's passive exposure to cigarette smoke after birth. 11 17. Studies in women and men suggest that cigarette smok- ing may impair fertility. 18. Experimental studies on tobacco smoke, nicotine, carbon monoxide, polynuclear aromatic hydrocarbons, and other con- stituents of smoke help define pathways by which maternal smoking during pregnancy may exert its aforementioned ef- fects. Peptic Ulcer Disease The 1979 Surgeon General's Report included evidence that cigarette smoking in males was significantly associated with the incidence of peptic ulcer disease and increased the risk of dying from peptic ulcer disease by approximately two-fold. The effect of smoking on pancreatic secretion and pyloric reflux demonstrated among men may provide a mechanism by which peptic ulcers develop. 1. Female smokers show a prevalence of peptic ulcer higher than that of nonsmokers by approximately two-fold. 2. The effect of cessation on healing is not known. Interactions of Smoking with Drugs, Food Constituents and Responses to Diagnostic Tests Most published studies investigating the effects of cigarette smoking on drug use have been performed on mixed popula- tions; factors specific for women have not been demonstrated to date. It has, however, been clearly demonstrated that women are prescribed and consume more prescription drugs than men. 1. Studies of selected drugs indicate that smoking may affect clinical responses and alter the dose required for an effective therapeutic result. 2. Smoking interacts with oral contraceptive use to increase the risk of myocardial infarction and subarachnoid hemor- rhage. 3. Common clinical laboratory parameters are altered in smokers compared to nonsmokers; the health significance of these changes is unknown. 4. Insufficient information exists for assessment of the im- pact of smoking on the nutritional needs of women. Psychosocial and Behavioral Aspects of Smoking in Women 1. The percentage of 17-18 year old women who smoke has shown a steady rise between 1968 and 1979. It now appears, however, that the increase in smoking prevalence among all 12-18 year old females has leveled off and begun to decline. Young women born after 1962 show a substantially reduced 12 initiation of smoking and will probably have a much lower pre- valence of smoking as adults. 2. Those young women who do begin to smoke are starting to smoke regularly at a younger age, with more than half of the male and female adolescents who begin to smoke starting before the 10th grade. 3. The earlier tobacco is used and the greater the number of cigarettes smoked per day, the less likely an attempt to quit will be successful. 4. The percentage of women smokers who smoke more than one pack per day is increasing. 5. Adolescent and adult women are more likely to use low-tar and-nicotine cigarettes, smoke fewer cigarettes per day and in- hale less deeply than do men, but the difference between the sexes in these patterns of smoking is decreasing. Adolescent and adult black women are more likely to be smokers than their white peers, but they smoke fewer cigarettes per day. 6. Adolescents from low income families, single parent families, and families with lower parental educational levels are more likely to become smokers. 7. Female and male adolescents are more likely to begin smoking if a parent or older sibling also smokes. 8. Adolescent smokers associate with peers who smoke and nonsmokers associate with nonsmoking peers. 9. Adolescent girls overestimate the percentage of their peers who smoke and they have a very positive image of the people in cigarette advertisements, but they are less likely than adoles- cent boys to see smoking as a social asset. 10. Adolescent girls who smoke tend to be more outgoing but feel less able to influence their future. 11. Adolescents experience stress due to feelings of unattrac- tiveness, incompetency in school achievement and personal re- lations, limited opportunity for personal growth and concern over future social and economic roles. This stress may be the common mechanism producing the increased rates of smoking in some groups. 12. The factors associated with successful quitting by adoles- cents of either sex are lower number of cigarettes smoked per day, higher educational aspirations and achievement, greater acceptance of the health risk of smoking, and having more nonsmokers among their friends. 13. It is possible that women and men modify their smoking in order to maintain a constant nicotine level. 14. Women are more likely than men to smoke in order to reduce stress. 15. Women at higher education and income levels are more 13 likely to succeed in quitting. Additional factors associated with successful quitting are a strong commitment to change, the use of behavioral techniques and reliable social support for quit- ting. Women have been reported to show lower rates than men of successful cessation following organized cessation programs, a difference which is less apparent in those programs that in- clude social support. 14 PART I: PATTERNS OF CIGARETTE SMOKING. PA'ITERNS OF CIGARETTE SMOKING Introduction This chapter traces the evolution of cigarette smoking among successive generations of American women and men during the twentieth century. The available evidence demonstrates that women have differed from men in their historical onset of wide- spread cigarette use, in the rate of diffusion of smoking among each new birth cohort, in their intensity of cigarette smoking, and in their use of various types of cigarettes. Four main conclusions emerge from this analysis. First, al- though men rapidly took up smoking during the early decades of this century, the proportion of adult female cigarette smokers did not exceed one-quarter until the onset of World War II. The peak intensity of smoking occurred among women born after 1920. Second, as a result of higher past rates of quitting and lower past rates of initiation -among men, as well as changes in the type of cigarette consumed, the smoking characteristics of women and men are now becoming increasingly similar. Third, the prevalence of cigarette smoking among adult American women and men is declining. This conclusion applies to all age groups, but with less certainty to the youngest generation of women. Fourth, increasing public awareness of the health con- sequences of smoking has resulted in significant changes in the nature of the cigarette product. Yet little is known about the effects of these product changes on the initiation, maintenance and cessation of smoking, particularly among women. Since the last review of cigarette smoking in the 1979 Report of the Surgeon General (24), two new national surveys have been performed under the sponsorship of the National Center for Health Statistics and the National Institute of Education. This chapter relies in part on the recent, preliminary results of these surveys. The Rise of Cigarette Smoking: 1900-1950 Although the use of cigarettes in the United States was ob- served as early as 1854 (42,48), consumption did not increase dramatically until after 1909. As shown in Figure 1, per capita consumption of all types of cigarettes increased by more than tenfold from 1900 to 1920. Despite a transient decline during the Great Depression, consumption increased from 665 cigarettes per capita in 1920 to 3,522 cigarettes per capita in 1950 (50). A continuous, nationally representative series of smoking prevalence rates during the period 1900 to 1950 is not publicly available. Nevertheless, numerous sources can be pieced to- 17 gether to characterize the differential growth of cigarette smoking among women and men. Figure 2 depicts estimates of the percentage of male and female current cigarette smokers in the greater Milwaukee area, as compiled by the Milwaukee Journal (38). In 1923, the first reported year of this survey, 51.8 percent of males aged 18 years and over smoked cigarettes. Sixty percent of male cigarette smokers also smoked pipes or cigars. In total, 87 per- cent of adult males used some type of tobacco (38). Although earlier survey estimates of male smoking rates are unavailable, it appears that the rise of cigarette consumption prior to 1923 reflected both the conversion of established male non-cigarette tobacco users to cigarette smoking and the re- cruitment of a new generatibn of younger male smokers during World War I. Innovations in cigarette production and market- ing have been cited as influential factors in this rapid growth (39,48,67). Camel cigarettes, a blend of lighter Burley smoking tobaccos with previously dominant Turkish cigarette tobaccos, were introduced in 1913 and within months attained a national market. Two similar brands, Lucky Strike and Chesterfield, fol- lowed in 1916 and 1919, respectively (39,48,67). During World War I, the War Industries Board estimated that soldiers of the Allied Armies consumed 60 to 70 percent more tobacco than they had used in civilian life (28,29). Cigarettes continued to dominate other forms of tobacco among male smokers throughout the 1920s and 1930s. By 1935, 62.5 percent of adult males in the greater Milwaukee area smoked cigarettes (Figure 2), while the percentages of pipe and cigar users had declined substantially. Average cigarette con- sumption frequency among men smokers increased from 3.7 packs per week in 1923 to 4.8 packs per week in 1935 (38). Consumption among men accelerated during World War II (Figures 1 and 2). In 1944, more than 25 percent of cigarettes produced in the U.S. were distributed to overseas forces (29), typically for free or at low cost (39), to the point where sub- sequent shortages developed in the domestic market. By 1948, 67.1 percent of adult males in the Milwaukee area smoked cigarettes (Figure 2). This estimate of the prevalence of cigarette use among urban men is confirmed by other local con- sumer surveys performed in that year. For example, in 1948, adult male smoking rates were 69.1 percent in Omaha, 67.4 per- cent in Birmingham, 69.4 percent in Philadelphia, 63.9 percent in Seattle, and 63.4 percent in San Jose (37). The growth of cigarette smoking among women occurred much later in the face of strong social taboos. Gottsegen noted that "the ultra smart set and women social leaders began to 18 smoke at the turn of the century" (13). By 1906, American "girl stenographers" were reported smoking cigarettes clandestinely (5). By 1919, some younger women in New York were reported smoking at dinner parties "with a trace of defiance" (48). By 1922, New York women were smoking openly on the streets and in bus tops (48). The first advertisement showing a woman smoking was Loril- lard's 1919 publicity for Helmar cigarettes (43,48). In 1926, a young women in a Liggett and Myers' Chesterfield advertise- ment did not smoke but pleaded, "Blow some my way" (6). In April, 1927, a Philip Morris advertisement for Marlboro cigar- ettes noted that "women, when they smoke at all, quickly de- velop discriminating taste," and that Marlboro cigarettes were as "mild as May" (2). In 1928, a Lucky Strike advertisement urged women to "reach for a Lucky instead of a sweet" (31,39,48). In 1934, Eleanor Roosevelt smoked cigarettes pub- licly (26). By 1940, handbags and cosmetic compacts were typi- cally designed to hold cigarettes (13). Although the Milwaukee Journal (38) reported that 16.7 per- cent of adult women smoked cigarettes in 1934 (Figure 2), prior estimates of women's smoking prevalence are sporadic. Wessel estimated that women consumed 5 percent of all cigarettes in 1924 (66). Moody's Investors Service estimated that women smoked 12 percent of all cigarettes smoked in 1929 (44). The average daily consumption of women smokers, as compared to men smokers, is not documented for that period. If men smokers consumed approximately twice as many cigarettes per day as women smokers (cf. the Milwaukee Journal's 1934 survey report that women's consumption frequency was 135 packs per year as compared to 244 packs per year for male smokers), and if the estimates of male smoking prevalence rates in Figure 2 are taken as nationally representative, and if there were approxi- mately 5 percent more adult males than adult females during the 1920 to 1930 decade (51), then Wessel's estimate yields a 6 percent adult female smoking prevalence in 1924 and Moody's estimate yields a 16 percent prevalence in 1929. The Milwaukee Journal series in Figure 2 must be interpreted in light of changes in the type of survey respondent and the wording of questions designed to elicit smoking practices (see caption to Figure 2). Moreover, this urban population series may not be representative of all American women. Neverthe- less, the publicly available survey data sources are consistent with the conclusion that smoking rates among women did not exceed one-quarter until the onset of World War II. Based on 10,000 applications for insurance policies during 1930 to 1940, Ley (32) estimated age-standardized smoking rates 19 of 63.9 percent of men and 20.8 percent of women aged 15 years and over. In 1935, Fortune Magazine, in the first nation-wide survey (12), reported that 52.5 percent of adult men and 18.1 percent of adult women smoked cigarettes. (See Table 1). Among those under 40 years of age, 65.5 percent of men and 26.2 percent of women were smokers. Among those over 40 years, 39.7 per- cent of men and 9.3 percent of women were smokers. Urban- rural differences in smoking were significant. The proportion of smokers ranged from 61.4 percent of men and 31.2 percent of women in cities with population over one million, to 44.1 percent of men and 8.6 percent of women in rural areas with population under 2,500. A survey of 250 urban women by the Market Re- search Corporation in 1937 reported 26 percent regular smokers and an additional 23 percent occasional smokers (47). After 1940, women's smoking rates accelerated, as new gen- erations of women, particularly younger women in urban areas, entered the labor force (see also title "Occupation and Envi- ronment" in this Report). In 1944, the Gallup Poll reported 48 percent adult male smokers and 36 percent adult female smok- ers (4). In 1949, the Gallup findings were 54 percent male and 33 percent female (4). Local consumer surveys of urban areas in 1948 revealed 37.6 percent adult women cigarette smokers in Milwaukee (see also Figure 2), 34.3 percent in Omaha, 35.6 per- cent in Birmingham, 46.7 percent in Philadelphia, 38.3 percent in Seattle, and 34.0 percent in San Jose (37). Conover, citing "trade journal" surveys in the three or four years prior to 1950, reported smoking prevalence rates of 65 to 70 percent among men and 40 to 45 percent among women (9). Although the differential growth of cigarette use among vari- ous socioeconomic groups is not well documented, the available data during this period suggest that male smoking rates de- clined with increasing income, while the relation of women's smoking to income was less clear. The Milwaukee Journal in 1945 noted 58 percent of men with monthly rents over $50 were smokers, and 75 percent of men with rents under $30 per month were smokers (38). Among women, the corresponding progor- tions were 32 and 37 percent respectively. In Mills and Porter's 1947 survey of Columbus, Ohio (36), 28.3 percent of white females and 64.9 percent white males smoked cigarettes, whereas 36.4 percent black females and 68.9 percent black males smoked cigarettes (estimates calculated from the age distribu- tion data provided in Table 6 of (36)). Kirchoff and Rigdon, in a survey of over 21,000 patients, visitors, and employees of hospi- tals in Houston and Galveston, noted that 63.2 percent white males, and 33.4 percent white females, 66.3 percent black males, and 32.2 black females smoked cigarettes (30). 20 All of the above findings reinforce the conclusion that the onset of widespread cigarette use among women lagged behind that of men by 25 to 30 years. This historical delay in the growth of cigarette smoking among women has also been documented for the United Kingdom (8,46,49). The Emergence of Filtertip Cigarettes: 1951-1963 As shown in Figure 1, total per capita consumption of cigar- ettes declined during 1953 to 1954. This decline was coincident with the appearance in the popular press of reports seriously suggesting a link between cigarette smoking and lung cancer (10,33,34,40). Thereafter, the consumption of filtertip cigarettes increased rapidly (Figure 1). In 1953 filtertip cigarettes consti- tuted 2.9 percent of cigarette production. By 1958, their share of production had increased to 45.3 percent, and by 1963 it was 58.0 percent (50). The transient decline during 1953 to 1954 in the number of cigarettes consumed was not clearly matched by a decrease in the proportion of cigarette smokers (27). At least in urban areas, the proportion of women smokers continued to increase. From 1953 to 1958, the prevalence of adult female smoking increased from 42.9 to 45;4 percent in Milwaukee (Figure 2), from 38.4 to 42.6 percent in Omaha, from 47.0 to 50.2 in Washington, D.C., and from 39.6 to 44.4 percent in San Jose (37). At the same time, both women and men rapidly converted to filtertip cigarettes. By 1958, filter cigarette use prevailed among 61 percent of women smokers and 42 percent of men smokers in Milwaukee, 54 percent of women smokers and 43 percent of men smokers in Omaha, 53 percent of women smokers and 47 percent of men smokers in Washington, D.C., and 59 per- cent of women smokers and 42 percent of men smokers in San Jose (37). In a nation-wide 1964 survey reported by the National Clearinghouse for Smoking and Health (64), 79 percent of adult female smokers and 54 percent of adult male smokers used filter cigarettes. Increasing Public Health Awareness: 1964- 1979 Per capita consumption reached a peak of 4,336 in 1963 (Fig- ure 1). It declined transiently after the appearance in January 1964 of the first Report of the Advisory Committee to the Sur- geon General (52). Per capita consumption continued to decline during the subsequent period of increased publicity concerning the health hazards of smoking (24,27). Since 1975, per capita consumption has declined at an average rate of 1.4 percent an- 21 .- 0 1900 `10 `20 `30 `40 `50 `E I total , I filter year FIGURE l.-Annual consumption of cigarettes and filtertip cigarettes per person aged 18 years and over, 1900- 1979* *Total per capita consumption data for 1917-19 and 1940-79 include overseas forces. Total per capita consumption for 1979 is preliminary estimate. Per capita consumption of filtertip cigarettes derived from annual data on the filtertip share of total cigarette production. SOURCE: U.S. Department of Agriculture (50). nually. The most recent 1979 estimate of 3,900 cigarettes per capita closely approximates that observed in 1952. Table 1 summarizes the results of selected, nationally repre- sentative surveys of adult cigarette use during the period 1935 to 1979. Except for the Fortune survey of 1935 (12) and the sup- plement to the Current Population Survey in 1955 (16), these data were collected under the sponsorship of the National Cen- ter for Health Statistics. The results of other recent national surveys of adult cigarette use (34,57,58,61,62,64), revealing very similar trends in the prevalence of smoking, were described in the 1979 Surgeon General's Report (24). Among adult males, the prevalence of regular cigarette use has declined continuously since 1965, with more marked de- creases in the intervals 1965 to 1970 and 1976 to 1978. (The abso- lute standard errors for the National Center for Health Statis- 22 tics estimates for 1970 to 1976 are less than 0.3 percent. The absolute standard errors for 1978 and 1979 are 0.6 percent.) Among adult women, the direction of change in smoking preva- lence is less clear. The estimates for the interval 1976 to 1979, however, suggest a recent downturn. The preliminary 1979 es- timate of 32.3 percent for the overall prevalence of adult cigarette smoking among both sexes represents the lowest re- corded value in at least 45 years. (The overall prevalence of cigarette smoking in the 1935 Fortune Magazine survey was 37.3 percent among adults of both sexes.) TABLE 1 .-Estimates of the prevalence of regular cigarette smoking among adults, United States, selected national surveys, 1935- 1979 Year Females Males 1935 18.1 52.5 1955 24.5 52.6 1965 33.3 51.1 1970 31.1 43.5 1974 31.9 42.7 1976 32.0 41.9 1978 29.9 37.0 1979 28.2 36.9 Data for 1978 are revisions of preliminary estimates reported in Harris (26). Data for 1979 are preliminary estimates based on a sample of over 13,000 interviews conducted during January-June 1979, provided by Health Interview Survey, National Center for Health Statistics. 1955 data represent persons 18 years and over. 1976 data represent persons 20 years and over. Estimates for the years 1965, 1970, 1974, 1978 and 1979 represent persons 17 years and over. SOURCE: Fortune Magazine (12), Haenszel, W. (16), U.S. Department of Health, Education, and Welfare (54-56, 58-59). These patterns of change in smoking prevalence applied to both white and black adults. For white men, the prevalence of regular smoking declined from 51.5 percent in 1965 to 36.3 per- cent in 1979. For black men, the prevalence of regular smoking declined from 60.8 percent in 1965 to 42.0 percent in 1979. For white women, smoking prevalence declined from 34.2 percent in 1965 to 28.2 percent in 1979. For black women smoking preva- lence declined from 34.4 percent in 1965 to 28.9 percent in 1979. Racial differences in cigarette use are discussed in greater de- tail in the chapter in this report entitled "Psychosocial and Be- havioral Aspects of Smoking in Women." Although the Milwaukee area data for 1964 to 1979 do not closely match these national estimates, Figure 2 does show a marked decline in smoking rates for both sexes during 1964 to 23 sco 19x) t920 1930 l940 l950 1960 1970 wcl YEAR FIGURE 2.-Percentage of adult current cigarette smokers in the greater Milwaukee area, 1924-1979* `Prior to 1941, the wording of the question eliciting cigarette use and the type of respondent are not recorded. From 1941 to 1954, men were asked, "Do you smoke cigarets?" From 1955 to 1959, all respondents were asked, "Do any men (women) in your household smoke cigarets with (without) a filter tip?" From 1960 to 1965 and in 1967, both men and women were asked "Have you bought, for your own use, cigarets with (without) a filter tip in the past 30 days?" In 1966 and from 1968 to 1979, both men and women were asked, "Have you bought, for your own use, cigarets with (without) a filtertip in the past 7 days?" All percentages reflect adults aged 18 years and over. Data for women from 1976 to 1979 (open circles) represent filtertip cigarette smokers only. SOURCE: Milwaukee Journal (38). 1970, a deceleration in the decline of smoking prevalence during 1971 to 1975, and a resumption of the decline in prevalence among men in the last four years. The cessation of cigarette smoking has been a significant fac- tor in explaining this overall decline in smoking prevalence (24). Column (i) of Table 2 presents estimates of the percentage of recent smokers who made a "fairly serious attempt to quit" 24 TABLE 2.-Estimated rates of attempted and successful quitting among adult, recent cigarette smokers, United States, 1970-1979 0) Percent of All Recent Smokers Who Attempted to Quit in Past Year (ii) Percent of Smokers Attempting to Quit in Past Year Who Reported Successfully Quitting (iii) Percent of All Recent Smokers Who Reported Successfully Quitting in Past Year Women 1970 1975 1978 `1979 Men 1970 1975 1978 1979 40.8 21.3 8.7 30.2 19.5 5.9 32.7 18.8 6.2 32.9 21.6 7.0 44.4 26.4 11.7 28.3 20.1 5.7 29.1 21.5 6.3 31.4 21.3 6.7 1970 and 1975 data from surveys of persons aged 21 years and over, conducted by National Clearinghouse for Smoking and Health. 1978 and 1979 data from the Health Interview Survey of persons aged 17 years and over, conducted by the U.S. National Center for Health Statistics. 1979 data are preliminary estimates based on interviews during January-June of that year. SOURCE: U.S. Department of Health, Education, and Welfare (54,61,62). within one year of the interview date. (Recent smokers include all current smokers plus those former smokers reported to have stopped within one year of interview.) Column (ii) shows what proportion of those attempting to quit regarded themselves as former smokers. Column (iii) shows the proportion of all recent smokers (whether or not they attempted or succeeded quitting) who reported themselves as recent former smokers. These data necessarily reflect respondents' self-assessment of both the seriousness of a quit attempt and their degree of success. Nevertheless, they do provide an indication of the representa- tive smoker's annual probability of attempting to quit, the probability of successful cessation given a quit attempt, and the overall annual smoking cessation rate. (The absolute standard errors in Table 4 are approximately 1.0 percent, 1.5 percent, and 0.3-0.5 percent for columns (i), (ii), and (iii), respectively.) All three indicators of smoking cessation were highest for men in 1970. Although a relatively large proportion of women smokers attempted to quit smoking in 1970 (column (i)), their 25 probability of success in that year was significantly lower than that of men (column (ii)). Quit attempt rates for both sexes (col- umn (i)) declined by 1975, but have increased in 1978 to 1979. With respect to the probability of attempting to quit and the success rate, adult men and women cigarette smokers are now indistinguishable. Table 3 displays recent changes in the distribution of cigarette brands according to F.T.C. "tar" contents. The propor- tion of adults smoking cigarettes with F.T.C. "tar" delivery less than 15 milligrams has increased from 9.5 percent of women and 2.9 percent of men in 1970 to 38.5 percent of women and 28.1 percent of me in the first half of 1979. A corresponding increase in the proportion of smokers of cigarettes with F.T.C. nicotine delivery less than 1.0 milligram was also observed. TABLE 3.-Estimated percentage distribution of adult current regular cigarette smokers according to F.T.C. "tar" content of primary brand, United States 1970-1979 Year Women 1970 1975 1978 1979 Men 1970 1975 1978 1979 Less Than 5.0 to 10.0 to 15.0 to 20.0 mg 5.0 mg 9.9 mg 14.9 mg 19.9 mg or More 0.7 2.0 6.8 67.1 23.4 1.2 1.2 15.0 75.1 7.5 5.3 8.8 21.1 59.2 5.7 5.6 9.5 23.4 55.4 6.1 0.2 0.9 1.8 61.3 28.1 0.6 1.1 11.0 68.1 19.2 3.3 6.2 13.5 63.5 13.6 2.6 8.5 17.0 60.1 11.8 1979 data are preliminary estimates provided by the National Center for Health Statistics. 1970 and 1975 data represent adults aged 21 years and over. 1978 and 1979 data represent adults aged 17 years and over. Estimates exclude those with unknown primary cigarette brand. SOURCE: U.S. Department of Health, Education, and Welfare (54,61,62). At the same time, the average daily cigarette consumption of adult smokers has increased. Table 4 shows recent changes in the distribution of reported daily cigarette consumption among current smokers. These data must be interpreted in light of possible underreporting biases (65) and, in particular, a strong tendency for respondents to round off their reported daily con- sumption to one pack. Nevertheless, the percent of women smoking less than one pack per day has declined, while the pro- portion smoking more than one pack per day has increased. Ex- cept for 1979, a similar trend is observed for men. (The absolute 26 standard errors of the 1978 and 1979 estimates are approxi- mately 1.0 percent.) The data of Table 4 represent the more recent portion of an apparently long run trend toward increasing daily cigarette consumption among regular smokers. In 1924, Milwaukee men smokers consumed an average of 10 cigarettes per day (38). In 1934, male smokers in Milwaukee consumed an average of 13.4 cigarettes per day, while women smokers consumed 7 per day (38). If cigarette consumption in 1935 was 1,564 per adult (Fig- ure 1 and (50)), and if the overall percentage of adult smokers was 37.3 percent (121, then mean consumption per adult smoker was 11.5 cigarettes per day. If consumption per adult was 3,597 in 1955 and if the prevalence of regular smoking was 37.6 per- cent (161, then mean consumption per adult in that year was 26.2 cigarettes. The corresponding calculation based on 1979 per capita consumption data and adult prevalence data (Figure 1 and Table 1) yields 33.3 cigarettes per day. Numerous epidemiological studies and other surveys per- formed during the period 1950 to 1965 have shown that for both TABLE I.-Estimated percentage distribution of adult current cigarette smokers according to reported daily consumption frequency, United States, 1965-1979 Year Women 1965 1970 1974 1976 1978 1979 Men 1965 1970 1974 1976 1978 1979 Percent Smoking Percent Smoking Less Than 15 25 Cigarettes or Cigarettes per Day More per Day 44.5 13.7 39.1 18.0 38.7 18.5 36.5 19.6 36.0 21.0 34.6 22.4 29.6 24.5 27.8 27.7 26.3 30.6 24.2 31.1 23.4 34.2 26.4 32.2 Data for 1976 represent persons aged 20 years and over. All other years represent persons aged 17 years and over. Data for 1979 are preliminary estimates based on interviews conducted during January-June of that year, provided by the Health Interview Survey, National Center for Health Statistics. SOURCE: Harris, J. E. (26), U.S. Department of Health, Education, and Welfare (54-56,58-59). 27 sexes, especially for women, the proportion of heavy smokers was larger among the younger age groups (14,16,19,20,22, 30,36,61,64). These findings applied to current daily cigarette consumption and lifetime maximum cigarette consumption. They are consistent with the hypothesis that regular smokers in past decades consumed fewer cigarettes per day than con- temporary smokers. The empirical relationships between rates of smoking cessa- tion (Table 2), changes in F.T.C. "tar" and nicotine delivery of cigarettes (Table 3), and increases in daily cigarette consump- tion (Table 4) are poorly understood (25). It is not known whether smokers of the lowest "tar" cigarettes are more or less likely to attempt to quit, or to succeed in quitting, than smokers of conventional filtertip or nonfilter cigarettes. The extent to which the act of switching to a lower "tar" cigarette may serve as a substitute for quitting may differ among women and men. The observed increase in daily cigarette consumption among current smokers could represent the effect of: higher cessation rates among lighter smokers; an increase in the daily cigarette consumption of continuing smokers; or an increased daily cigarette consumption of new entrants into the smoking popu- lation; or a combination of these effects (24). The relationship of these possible mechanisms to the observed increase in the pro- portion of filtertip cigarette and low "tar" cigarette smokers is not well elucidated. Exposure to Cigarette Smoke Among Successive Birth Cohorts Figures 3 and 4 depict estimates of the prevalence of current cigarette smoking from 1900 to 1978 among successive birth cohorts of men and women. Each continuously graphed time series corresponds to individuals born during a particular dec- ade. For example, among women born from 1931 to 1940 (Figure 4), who are now 40 to 49 years old, the prevalence of smoking rose rapidly during the post World War II period and reached a peak of 45 percent by 1963. Thereafter, their overall prevalence of smoking declined to 39 percent in 1978. These prevalence data were constructed from the reported lifetime smoking histories of over 13,000 respondents to the Health Interview Survey during July to December, 1978. (For related applications of this methodology, see 7,15,27). Although the accuracy of survey recollection of age started smoking, age of smoking cessation, and the duration of significant, temporary periods of abstinence is not known, no particular source of recall bias has been identified (15,16). However, the significantly higher mortality rates of continuing smokers, as compared to 28 70 60 50 k 40 z 8 E a 30. 20 10 k 0 1900 l9m MEN 1911- 2r 1920 YEAR FIGURE 3.-Changes in the prevalence of cigarette smoking among successive birth cohorts of men, 1900-1978 Calculated from the results of over 13,000 interviews conducted during the last two quarters of 1978, provided by Division of Health Interview Statistics, U.S. National Center for Health Statistics. SOURCE: U.S. Department of Health, Education, and Welfare (60). nonsmokers or former smokers (1,11,1'7,18,41,45,46,52), intro- duces a selection bias that may understate the prevalence of past smoking for the oldest cohorts. For example, on the basis of the insurance life tables recently reported by Cowell and Hirst (ll), a male cigarette smoker at age 32 has an estimated 25 Percent probability of surviving to age 80, as compared to 49 29 YEAR FIGURE I.-Changes in the prevalence of cigarette smoking among successive birth cohorts of women, 1900-1978 Calculated from the results of over 13,000 interviews conducted during the last two quarters of 1978, provided by Division of Health Interview Statistics, U.S. National Center for Health Statistics. SOURCE: U.S. Department of Health, Education, and Welfare (60). percent for a nonsmoker. The estimated probabilities of surviv- ing to age 60 are 80 percent for smokers and 93 percent for nonsmokers, respectively. Therefore, the peak smoking preva- lence rate of men born before 1900, calculated from 1978 survey responses to be 46 percent in 1937, could actually have been as high as 65 percent. Since individuals who quit smoking have a higher survival than continuing smokers (18,45), the actual point in time at which smoking rates peaked in this cohort may have been later than 1937. This effect is less likely to be impor- tant among men born after 1910, who are now approaching 70 years old. A similar calculation for men born, for example, be- tween 1911 and 1920 reveals that their peak smoking rate may have been understated by at most 2 or 3 percentage points. This source of bias is likely to be less important for older women. On the basis of age-specific mortality data reported by 30 Hammond in 1966 (18, Appendix Table 2b), women continuing to smoke cigarettes from age 35 would have an estimated 48 per- cent chance of surviving to age 80 years, as compared to 54 percent for nonsmokers. The estimated probabihties of survival to age 60 would be 91 percent for smokers and 93 percent for nonsmokers. If these survival data are currently applicable to women smokers and nonsmokers, then the estimated peak pre- valence rate of smoking among women born before 1910 could be understated by only one to two percentage points. Despite these possible biases, the predicted percentages of current smokers in Figures 3 and 4 are consistent with past survey and epidemiological data on the smoking habits of dif- ferent age groups (12,14-16,19-23,30,35,36,55). Comparison of Figures 3 and 4 reveals the following conclu- sions. (a) The most marked differences in smoking prevalence among men and women appeared in those individuals born be- fore 1910, who are now over `70 years of age. (b) Women born between 1921 and 1940, who are now approaching 40 to 59 years of age, experienced the highest smoking prevalence rates. These women have not yet reached the age where the absolute excess deaths of smokers over nonsmokers are expected to be- come substantial (1). (c) Among successive cohorts of men and women, the age of peak smoking prevalence has declined. Among younger cohorts, the peak smoking prevalence rates are declining, although the effect is less marked for women. Men born between 1911 and 1920 reached a peak smoking prevalence of 71 percent during 1946 to 1948, while those born 1941 to 1950 reached a peak smoking prevalence of 58 percent in 1968 to 1969. Women born 1921 to 1930 reached a peak prevalence of 44 per- cent in 1958 to 1960, while those born in 1941 to 1950 reached a peak smoking prevalence of 41 percent in 1970 to 1973. (d) Among men born 1951 to 1960, the rate of increase of smoking prevalence was slower than in previous cohorts. This slowing of the diffusion of smoking practices was coincident with the in- creased publicity concerning the health risks of smoking and the relatively high rate of quitting smoking among adult males in the late 1960s. A similar effect is not clearly discernible for young women in this cohort. In both sexes, among individuals who are now approaching ages 20 to 29, the prevalence of smok- ing has apparently peaked. Smoking rates among men and women in this age group are now nearly indistinguishable. Figure 5 depicts the mean age of starting regular smoking among successive birth cohorts, calculated from the same data as for Figures 3 and 4. The age of onset of smoking among women declined continuously during this century, to the point where it is nearly indistinguishable from that of men. As a re- 31 1 1 I 1 I * -l9ocl 1901-10 l9ll-20 193140 1921-30 &&l-6( Birth Cohort FIGURE 5.-Mean age of onset of regular smoking among successive birth cohorts of women and men SOURCE: U.S. Department of Health, Education, and Welfare (60). sult, each successive cohort of lifelong continuing women smok- ers will have an increasing number of years of exposure to cigarette smoke. Figure 6 depicts the accumulated years of cigarette smoking per capita, up to 1978, for each birth cohort. These magnitudes correspond to the total areas under each cohort prevalence curve in Figures 3 and 4. Among women, individuals born 1911 to 1920 have thus far experienced the largest total exposure per capita. However, as seen from Figure 4, unless the smoking pre- valence rates of women born during 1921 to 1940 decline more rapidly in the future, the lifetime exposure of these latter cohorts is likely to exceed that of the 1911 to 1920 cohort. It is not clear, however, whether the lifetime exposure of men born 32 from 1921 to 1940, now 50 to 69 years of age, will exceed that of previous generations. With each successive cohort, the ratio of female to male exposure increasingly approaches one. As a result of the rapid diffusion of filtertip cigarettes after 1950 (Figure l), each successive birth cohort was exposed to a different proportion of filtertip and nonfilter cigarettes. Details of the respondent's past history of cigarette brand use were not obtained in the 1978 Health Interview Survey. Such data, how- ever, are available from a series of over 2,000 interviews of cur- rent and former smokers aged 21 years and over, conducted by the Nationals Clearinghouse for Smoking and Health in 1975 (62). Figure 7 depicts, for the same birth cohorts, the proportion of lifetime years of smoking that represents filtertip cigarette. use. (The birth dates of the youngest cohorts in Figures 6 and 7 do not match due to differences in survey date and eligible age group.) Among men, there is a distinct, monotonically increas- ing relation between the proportion of filtertip cigarette expo-. sure and birth date. The corresponding relationship among women born before 1930 reflects their lower smoking cessation rates and, therefore, their continued use of filter cigarettes (62). A woman born in 1925, for example, who began smoking at age 21 (Figure 5), and who switched to filtertip cigarettes in 1957 (Figure 11, has now been smoking filtertip cigarettes for over two thirds of her smoking career and 40 percent of her entire life. The prevalence of cigarette smoking, age of initiation, lifetime duration of smoking, and the extent of use of various types of cigarettes are not the only measures of cigarette smoke expo- sure among a particular population. Trends in depth of inhala- tion, fraction of cigarette actually smoked, and other dimen- sions of the style of smoking also affect smoke exposure. How- ever, as discussed in the 1979 Surgeon General's Report (241, these are difficult to determine from survey data. In view of the concern over the accuracy of contemporaneous survey reports of daily cigarette consumption (65); past accounts of the time course of daily cigarette consumption would be difficult to as- sess accurately. Nevertheless, the evidence presented in the previous section is consistent with the conclusion that the aver- age daily cigarette consumption among regular cigarette users has increased among each successive birth cohort. Cigarette Smoking Among Young Women The more marked decline in peak smoking prevalence among men born between 1951 and 1960, now approaching 20 to 29 years of age, reflected a slowing in the rate of initiation of smok- 33 .-. .s- - ,-- - - - -1900-1901-x) 1911-x)-1921-301931-40 1941-50 1951-60 Birth Cohort FIGURE 6.-Accumulated years of cigarette smoking per person among successive birth cohorts of women and men, 1978 SOURCE: U.S. Department of Health, Education, and Welfare (60). ing that was not observed in women of the same age group. This trend appears to be continuing in the next birth cohort. Table 5 reports the results of nation-wide surveys of teenage cigarette smoking during 1968 to 1979. The most recent survey, conducted by the National Institute of Education during late 1978 and early 1979, presents the preliminary results of over 2,600 telephone interviews of individuals aged 12 to 18 years. In this survey, but not in the others reported in Table 5, women and men 19 years of age were also interviewed. Otherwise, the survey sampling techniques and interview questions regarding smoking practices were the same for all the surveys. (See notes to Table 5). The data in Table 5 support the conclusion that the rate of initiation of smoking among even the youngest men is declining, 34 - - W-I - - -1900 1901-K) 1911-20 X32-30 1931-4011-50-1951-54 Birth Cohort - FIGURE 7.-Proportion of years smoking filtertip cigarettes among successive birth cohorts of women and men, 1975 Calculated from the results of over 2,000 smoking histories of men and women who had ever smoked, collected by National Clearinghouse for Smoking and Health. SOURCE: U.S. Department of Health, Education, and Welfare (62). an effect that is not present among young women. These results must be interpreted in light of sampling variability. (The abso- lute standard errors on the 1979 estimates for ages 15-16 and 17-18 are about 2 percent.) As in adult surveys, non-response biases must also be considered. Nevertheless, the findings in Table 5 are consistent with other nation-wide estimates of smoking rates among young women and men. The prevalence of current regular smoking among respondents 17 to 19 years of age in this survey was 28.1 percent for females and 22.8 percent for males. The comparable rates for women and men aged 17 to l9 from the Health Interview Survey were 29.2 percent and 27.5 percent, respectively. An analysis of the growth of smoking Prevalence among this group, performed in the same manner as 35 TABLE 5 .-Estimated percentage of current, regular cigarette smokers, ages 12-18, United States, 1968-1979 Year Ages 12-14 Ages 15-16 - Ages 17-18 Females 1968 1970 1972 1974 1979 Males 1968 1970 1972 1974 1979 - 0.6 9.6 18.6 3.0 14.4 22.8 2.8 16.3 25.3 4.9 20.2 25.9 4.4 11.8 26.2 2.9 17.0 30.2 5.7 19.5 37.3 4.6 17.8 30.2 4.2 18.1 31.0 3.2 13.5 19.3 Nation-wide surveys performed by National Clearinghouse for Smoking and Health, 1968-1974, and National Institute of Education, 1979. Current regular smokers in all surveys include all those who smoke cigarettes at least weekly. In 1979, approximately SO percent of current regular smokers used cigarettes on a daily basis. For 1979 only, 29.7 percent males and 31.9 percent females, aged 19, were reported as regular smokers. SOURCE: US. Department of Health, Education, and Welfare (63). that of Figures 3 and 4, suggested that smoking rates among this group of women grew rapidly and exceeded those of men by 1975. The future smoking habits of this generation of young women cannot be accurately predicted. Smoking among adolescent women is discussed in greater de- tail in the chapter entitled "Psychosocial and Behavioral As- pects of Smoking in Women" in this Report. Summary 1. Women have differed from men in their historical onset of widespread cigarette use, in the rate of diffusion of smoking among each new birth cohort, in their intensity of cigarette smoking and their use of various types of cigarettes. 2. Men took up cigarette smoking rapidly at the beginning of the twentieth century, especially during World War I. Cigar- ettes rapidly replaced other forms of tobacco. By 1925, approxi- mately 50 percent of adult males were cigarette smokers. Smok- ing among men accelerated rapidly during World War II. By 1950, the prevalence of cigarette use among men approached 70 percent in some urban areas. 3. The onset of widespread cigarette use among women lag- ged behind that of men by 25 to 30 years. The proportion of adult 36 women smoking cigarettes did not exceed one-quarter until the onset of World War II. 4. Between 1951 and 1963, increasing proportions of women and men smokers converted to filter-tip cigarettes. By 1964, 79 percent of adult women smokers and 54 percent of adult men smokers used filter cigarettes. 5. After reaching a peak value of 4,336 in 1963, annual per capita consumption of cigarettes declined in 1964, 1968-70, and in the period since 1975. The most recent estimate of 3,900 cigarettes per capita in 1979 is approximately equal to that ob- served in 1952. 6. From 1965 to 1978, the proportion of adult men cigarette smokers declined from 51 to 37 percent. The preliminary esti- mate of adult men's smoking prevalence for 1979 is 36.9 percent. From 1965 to 1976, the proportion of adult women smokers re- mained virtually unchanged at 32 to 33 percent. Since 1976, the proportion of women smokers has declined to below 30 percent. For 1979, the preliminary estimate of adult women's smoking prevalence is 28.2 percent. The overall smoking prevalence of 32.3 percent for both sexes in 1979 represents the lowest re- corded value in at least 45 years. 7. The proportion of adult smokers attempting to quit smok- ing declined from 1970 to 1975, but increased in 1978-1979. In contrast to past years, the proportions of women and men now attempting to quit smoking, and their reported quitting rates, are indistinguishable. Approximately one in three adult smok- ers now makes a serious attempt to quit smoking during the course of a year. Approximately one in five of those who attempt to quit subsequently succeed. 8. The proportion of adult smokers using lower "tar" and nicotine brands has increased substantially. In 1979,39 percent of adult women smokers and 28 percent of adult men smokers reported primary brands with F.T.C. "tar" delivery less than 15.0 milligrams. It is not known whether smokers of the lowest "tar" cigarettes are more or less likely to attempt to quit smok- ing, or to succeed in quitting, than smokers of conventional fil- tertip or non-filter cigarettes. 9. The average number of cigarettes smoked by women and men current smokers has increased. The relationship of this finding to recent declines in the average F.T.C. "tar" and nicotine deliveries of cigarettes is not well understood. 10. With each successive generation, the smoking character- istics of women and men have become increasingly similar. 11. Among women, the average age of onset of regular smok- ing progressively declined with each successive birth cohort- from 35 years of age for those born before 1900, to 16 years of 37 age among those born 1951 to 1960. The average age of onset of regular smoking among young women is now virtually identical to that of young men. 12. Maximum smoking prevalence rates have declined sub- stantially in recent birth cohorts of men. Men born 1931 to 1940 reached a peak smoking proportion of 61 percent during 1960- 62, while men born 1941 to 1950 reached a peak smoking propor- tion of 58 percent in 1968-69. Men born 1951 to 1960 reached a peak smoking proportion of 40 percent in 1976. Among recent cohorts of women, peak smoking prevalence rates have declined to a much smaller extent. Women bo% 1931 to 1940 reached a peak smoking proportion of 45 percent in 1966-68, while women born 1941 to 1950 reached a peak smoking proportion of 41 per- cent in 1970-73. Women born 1951 to 1960 reached a peak smok- ing proportion of 38 percent in 1976. Among the generation born 1951 to 1960, the proportions of women and men smoking cigarettes are now virtually identical. 13. The proportions of women and men smokers in each age group have declined. Among those born before 1951, this decline in smoking prevalence resulted mainly from smoking cessation. By contrast, the observed decline in smoking prevalence among younger men born 1951 to 1960 has resulted from both smo!cing cessation and a lower rate of smoking initiation. This decline in the rate of onset of smoking among young men has not been observed for young women. 14. Recent survey data on adolescent smoking habits reveal that by ages 17 to 19, smoking prevalence among women ex- ceeds that of men. This finding supports the conclusion that the rate of initiation of smoking among young men-but not that of young women-is declining. The future cigarette use of the youngest generations of women is uncertain. 15. With each successive birth cohort, the accumulated years of cigarette smoking per woman has progressively approached the accumulated years of cigarette smoking per man. Each suc- cessive birth cohort has also experienced progressively smaller sex differences in the fraction of lifetime years of smoking that represents filtertip cigarette use. 16. Among men born during this century, each successive birth cohort has thus far experienced fewer cumulative years of cigarette smoking, higher proportionate exposure to filter-tip cigarettes, and lower smoking prevalence rates. This relation- ship between birth date and cigarette smoke exposure does not hold for women. Women born 1921 to 1940 have experienced substantially higher smoking prevalence rates than earlier generations. Unless they quit smoking in substantial numbers, these women, currently aged 40 to 59, will surpass older women 38 in total years of cigarette smoking per capita, the total years of nonfilter cigarette smoking per capita, and in the total number of cigarettes smoked. The health consequences of this enhanced exposure to cigarette smoke among women are likely to be more prominent in the coming decades. References (1) ADAMS, E.E. Mortality. In: Smoking and Health. A Report of the Sur- geon General. U.S. Department of Health, Education, and Welfare, Public Health Service, Office of the Assistant Secretary for Health, Office on Smoking and Health, January 1979, pp. 2-1 to 2-47. (2) ADVERTISING & SELLING. Marlboro makes a direct appeal. Advertis- ing and Selling 825, March 23, 1927. (3) AMERICAN INSTITUTE OF PUBLIC OPINION (GALLUP). The Gal- lup Opinion Index, September 1970, July 1971, July 1972, June 1978. (4) AMERICAN INSTITUTE OF PUBLIC OPINION (GALLUP). The Gal- lup Poll Public Opinion, 1935-1971 Series, pp. 477-1501; 1972-1977 Series, pp. 274-1203. (5) BAIN, J., JR., WERNER, C. Cigarettes in Fact and Fancy. Boston, H.M. Caldwell Co., 1996. (6) BONNER, L. Why cigarette makers don't advertise to women. Advertis- ing & Selling 7: 21, October 20, 1926. (7) BURBANK, F. U.S. lung cancer death rates begin to rise propor- tionately more rapidly for females than for males: a dose-response effect? Journal of Chronic Diseases 25: 473-479, 1972. (8) CAIRNS, J. The cancer problem. Scientific American 233(5): 64-78, November 1975. (9) CONOVER, A.G. Discussion of Elmo Jackson's paper. Journal of Farm Economics 32(4, Part 2): 923-924, November 1950. (10) CONSUMERS UNION. Cigarette smoking and lung cancer. Consumer Reports 19: 54-92, February 1954. (11) COWELL, M.J., HIRST, B.L. Mortality Differences Between Smokers and Nonsmokers. Worcester, Massachusetts, State Mutual Life Insur- ance Company of America, October 22, 1979. (12) FORTUNE MAGAZINE. The Fortune survey. III. Cigarettes. 12(l): 68, 111-116, July 1935. (13) WTTSEGEN, J.J. Tobacco. A Study of Its Consumption in the United States. New York, Pitman Publishing Corp., 1940. (14) GRAHAM, E.A. Primary cancer of the lung with special consideration of its etiology. Bulletin of the New York Academy of Medicine 27(5): 261-2'76, May 1951. (15) HAENSZEL, W., SHIMKIN, M.B. Smoking patterns and epidemiology of lung cancer in the United States: are they compatible? Journal of the National Cancer Institute 16(6): 1417-1441, June 1956. (16) HAENSZEL, W. SHIMKIN, M.B., MILLER, H.P. Tobacco Smoking Pat- terns in the United States. U.S. Department of Health, Education, and Welfare, Public Health Service, Monograph No. 45, 1956. (17) HAMMOND, E.C. Life expec