TABLE &-Prevalence, awareness, and control rates of hypertension, persons 2&74 yeara of age, united states, 1964%1992,1974-1975, 1976-19801 YW Percentage of population with hyperten- sion ' Percentage of total with hypertension Aware, Aware, Aware,' medication, medication, Unaware' u&Zion no control controlled 1960-1962 20.3 51.1 17.6 15.3 16.0 1974-1975 22.1 36.4 29.4 14.6 19.6 19761990 22.0 26.6 17.2 22.1 34.1 ' Bate ageadjusted by the direct method to the population at the midpoint of the 19761990 National Health and Nutrition Examination Survey. ' Systolic blood pressure 160 mm Hg or greater, or di&.olic blood pressure 95 mm Hg or greater. or on antihypertensive medication. ' Reported never told by phynician of having hypertension. ' Three with hypertension taking antihypstensive medication whose blood p-we wan not hypertensive. SOURCE: National Center for Health Statistica (32). TABLE O.-Percentage of adults with serum cholesterol levels of 269 mg/199 ml and over, by sex and age, United States, Health Examination Survey (HES) 1990-1962 and Health and Nutrition Examination Survey (HANES) 1971-1974' Age HJB, M&1962 Men Women HANIB, 1971-1974 Men Women Percentage Total. age 16-74 17.6 22.7 14.7 17.5 16-24 3.9 4.6 2.8 3.0 2544 10.4 7.4 8.2 5.6 35-44 20.2 12.9 17.1 9.6 4a54 25.7 28.0 24.1 24.6 5664 23.5 49.7 20.2 35.3 65-74 21.6 51.0 20.9 40.7 ' Age adjusted by the direct method to 1971-1974 civilian noninstitutional&d population. NOTE: All choleat.eml values have been a&ot.ed to approximate the values of Abel1 et al. (Abell, L.L.. Levy. G.B., Bralie. B.B., Kendall, F.E. A simplified method for the estimation of total cholesterol in amum. and demonstration of its epeciricity. Journal of Eiologiml Chemistry 196: 357-265, 19521, the common referenced metlmd, by reducing the 1960-1962 data by 7.6 percent and the 1971-1974 data by 4.5 percent. SOURCE: National Center for Health Statistics (24X socioeconomic level and lesser declines in poorer areas of the country are also consistent with a favorable impact of smoking prevention or cessation efforts on CHD mortality, in view of the clearly demon- strated inverse relationship of male income level and prevalence of smoking. 351 TABLE 10.-Regression coefficients, risk ratios, and statistical significance for the risk of cardiovascular disease in 8 years, men and women, age 36-74 years, Framingham heart study Risk ratice evaluated MultiDle regreiion coefficient ' T' at age 55' Risk ratio Flisk factor difference Rick factor c!igamw smoking Serum cholesterol Cholesteml/age interaction Systolic blood p-re Glucces intolerance cigarette smoking senlm eholenterol Cbolesteml/age interaction Systolic blood preeeure Glucose intolerance MEN 0.580 0.020 4mo1 0.017 0.410 WOMEN 0.233 0.019 -0.001 0.015 0.757 6.46 1.8 3.65 1.3 -2.61 - 9.12 1.4 2.92 1.5 2.37 1.3 Smoker/nonsmoker 2.66 1.2 46 mgldl -2.77 - - 6.59 1.4 M-&l 5.40 2.1 Preeentlatwnt Smoker/nonsmoker 42 m&ll 20 mm xig Present/absent ' Unetandardisd meffcient of the multiple risk function for cardiovascular dineme within 8 years with the independent variables being w-am cholasteml. &&stem1 timea age. syetolie blood premure. cigar&e smoking, gluame intaleran~> left ventricular hypertrophy on ECG. age, and age sguared; estimati over the age range 3& 74 yean. ' Thme tik fectors are statistically significant for both men and women. The critical value of T ia appmxbnately equal to 2.0 at a=OM. ' The hypothetical risk of development of cardiovsseular diwase asawiated with the 6,.&&d difference in risk rector levels when other risk factors in the model are held constant. A ratio greater than 1 reprecenia pmitive amociation with cardiovancular d&we. For serum cholesterol and systolic blood pressure, the difference chceen wan one standard deviation of the measurement. SOURCE: McGee and Abbott Ml. Some questions remain unanswered regarding the contribution of smoking cessation to the decline in CHD mortality. The percentage of smokers who are heavy smokers appears to be increasing, although it is not known whether this represents a greater cessation rate among lighter smokers than among heavier smokers. The percentage decline in CHD mortality for women has been as large as for men, although proportionately fewer women than men have given up smoking. Assertions that preventive measures have re- sulted in smoking changes that caused the decline in CHD mortality differences by age, socioeconomic status, and geographic area are based on limited available data. 352 Conclusion The evidence supports the conclusion that changes in smoking habits have contributed to substantial improvement in mortality rates from the cardiovascular diseases in the United States. 353 Technical Notes International Classification of D&eases Tables A and B contain the code numbers of the International Classification of Diseases (ICD) applicable to the causes of death described in this report (16,20,44, 45). Between each revision of the ICD there are breaks in the continuity of these classifications, affecting some diseases more than others. For cardiovascular dis- ease, the most serious breaks in continuity are between the seventh and eighth revisions and between the eighth and ninth revisions for CHD and for hypertensive disease. The cause of death commonly referred to as coronary heart disease (CHD) was listed in both the sixth and seventh revisions of the ICD (1949-1957, 195&1967) as "Arteriosclerotic heart disease, including coronary heart disease," code 420; in the eighth revision (1968-1978) as "Ischemic heart disease," codes 410-413; and in the ninth revision (after 1978) as "Ischemic heart disease," codes 410-414. Expected Minus Observed Deaths Multiplying the 1970 age-specific death rates Wyear age groups) for total cardiovascular diseases times the 1980 census gives an estimate of the number of cardiovascular disease deaths expected in 1980: 1,294,564 deaths, based on the level of mortality in 1970. An estimate of the number of cardiovascular disease deaths observed in 1980 is 1,005,692. This latter estimate is made by combining the estimated 989,000 deaths from major cardiovascular d&eases in 1980 (ICD/S codes 390-448) and the 4,803 deaths from diseases of the veins in 1980 (ED/S codes 451-459) (27, 29). The difference is 288,872 cardiovascujar disease deaths "averted" in 1980 because of a decline in mortality from the level in 1970. Multiplying the 1963 age-specific death rates W&year age groups) for coronary heart disease (ICD/7 code 420) times the 1979 popula- tion estimate gives the number of CHD deaths, 804,000, expected in 1980, on the basis of the level of mortality in 1963 (2, 25, 27). The observed number of deaths from CHD in 1980 for ED/9 codes 410- 414 was 566,000, or 238,000 fewer than expected, based on the level of mortality in 1963. This procedure assumes reasonably good comparability of ICD classification of CHD in these 2 years. Age-Adjusted Rates Age adjustment for this Report is by the direct method. Age- specific death rates in l@year age groups are multiplied by the "standard million" for 1940-the U.S. population by age as enumer- ated in that year. 354 TABLE A.-Codes of the 6th, 7th, 8th, and 9th revisions of the International Classification of Diseases for Selected Diagnoses Diagnosis 1949-1967 1966-1978 1979 6th and 7th revisions 6th revision 9th revision Cardiovascular diseases 330-334,400460 Coronary heart disease 420 Acute myocardial infarction no code for this diagnosis Other coronary heart disease no code for this diagnosis Cerebrovascular diseases 330-334 Hypertensive disease 440-M7 Other diseases of arteries 450-456 Atherosclerosis 450 Aortic aneurysm 451 Other 452456 All other cardiovascular disease 403-416. 421-434, 460-460 Lung cancer 162, 163 Other cancers 140-161, 164-205 Diabetes mellitus 260 Influenza and pneumonia 4so493 Chronic obstructive pulmonary disease 500, 501, 527.1 Cirrhosis of the liver 561 Accidents, poisonings, and violence FBOO-Em5 390-456 410-413 410 411413 430-436 44cM48 440 441 442-448 390-390. 420-429, 450-456 162 14Si61. X3-209 250 47&474, 400-46 493-492, 519.3 571 E9oa-E999' 390-459 410-414 410 411414 4zQ-436 401-405 440440 440 441 442-440 390-398, 415-429, 451-459 162 140-161, 163-205 2.54 480-487 490492, 494-496 571 EI4mo-E999 SOURCE: World Health Organization (44,45), National Center for Health Statistica (20). TABLE B.-Iutmnational classification of diseases codes for cardiovascular-renal diseases1 and cardiovascular diseases*, 1900-1979 YearS Revieion inuse codes 1St 2nd 3rd 4th 5th 193%1946 6th 194%1966 7th 1959-1967 8th 1966-1978 9th 197% 190&1909 1910-1920 1921-1929 I%?#-1936 47,64-a, 77-66,120, 142 47, 64-66, 77-66, 120, 142 51, 74, 75, 03. 87-90. 9lb, 91c, 9%96, 129, 151 56, 82.9&95.97-103, 131. 132 ' Thmugb 6th revision. ' After 6th revision. SOURCEz Moriyama et al. (16-h National Center for Health 6tatietia Cm). World Health Chgmizatior, (&)b). Population Estimates Death rates for census years and for years prior to 1961 are based on the resident or census population estimates that were available at the time the official U.S. vital statistics were prepared. Rates for 1961 to 1969, however, are based on estimates of the resident population revised to reflect the 1970 census, and rates for 1971 to 1979 are based on estimates of the resident population revised to reflect the 1980 census (I, 2). 356 References (I) BUREAU OF THE CENSUS. Estimates of the population of the United States, by age, sex, and race: April 1, 1960 to July 1, 1973. Current Population Reports, Population Estimates, and Rejections. U.S. Department of Commerce, Social and Economic Statistics Administration, Bureau of the Census. Series P-25, No. 519, April 1974,79 pp. (2) BUREAU OF THE CENSUS. P re 1 iminary estimates of the population of the United States, by age, sex, and race: 1970 to 1981. Current Population Reports. U.S. Department of Commerce, Social and Economic Statistics Administration, Bureau of the Census. Series P-25, No. 917, July 1982, 65 PP. (3) ELVEBACK, L.R. Coronary heart disease in Rochester, Minn., 1950-1975: Incidence and survivorship. In: Havlik, R.J., Feinleib, M., Thorn, T., Krames, B., Sharretta, A.R., Garrison, R. (Editors). Proceedings of the Conference on the Decline in Coronary Heart Disease Mortality, Bethesda, Maryland, October 24-25, 1978. Department of Health, Education, and Welfare, Public Health Service, National Institutes of Health, NIH Publication No. 79-1610, May 1979, pp. 116122. (4) FEINLEIB, M., THOM, T.J., HAVLIK, R.J. Decline in coronary heart disease mortality in the United States. In: Gotto, A.M., Jr., Paoletti, R. (Editors). Athemsclemsis Reviews. Volume 9. New York, Raven Press, 1982. pp. 29-42. (S, FRIEDMAN, G.D. Decline in hospitalizations for coronary heart disease and stroke: The Kaiser-Permanente experience in northern California, 1971- 1977. 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APPENDIX B: TRENDS IN U.S. CIGARETTE USE, 1965 TO 1980 introduction This discussion of national trends in adult cigarette smoking over recent years in the United States includes data on prevalence, consumption, and cessation. It focuses on adult cigarette smoking patterns and cessation by age and sex cohorts. Data were drawn from an analysis of three national surveys by the National Center for Health Statistics (NCHS) and three other national surveys on adult use of tobacco conducted by the former National Clearinghouse for Smoking and Health over the period from 1965 through 1980 (6, 7,s). A brief description of the data sources is presented, followed by a discussion of the data. Surveys of Tobacco Use The 1999 Survey on the Use of Tobacco Two separate national probability sample surveys on adult usage of and attitudes toward tobacco conducted by the National Clearing- house for Smoking and Health in 1966 have been combined and are treated here as a single survey. One study design imposed a two-way stratification on all house- holds in the continental United States, classifying each household by three types of population and nine geographic areas. The other design divided the entire area of the United States into approximate- ly 1,700 primary sampling units PSUs). Weighting procedures resulted in the selection of 5,770 respondents. Within each household, the first eligible respondent (age `21 or older) was the person interviewed; all current and former smokers were also interviewed, but only a subsample of those who had never smoked was interviewed. Weighting procedures were used to bring the three groups into balance. The 1970 and 1975 Surveys on the Adult Use of Tobacco The 1970 and 1975 surveys sponsored by the National Clearing- house for Smoking and Health employed the same sampling and interviewing methodologies. Where possible, questions were phrased similarly. The questionnaires for current, former, and never smokers differed slightly. In both surveys, the sample design consisted of two parts: a national probability sample of telephone households and a national probability sample of nontelephone households. The respondent selection procedure was designed to produce 75 percent of the interviews with "ever" smokers and 25 percent with "never" smokers. Weighting procedures were used to compensate for this oversampling of ever versus never smokers. Other weighting factors were used to adjust for age, sex, and smoker mix of the household. The weighted number of respondents (age 21 or older) was 5,875 in 1970 and 12,079 in 1975. Smoking Supplement to the National Health Interview Survey The National Health Interview Survey (NHIS), a continuous nationwide sample personal household interview survey by the National Center for Health Statistics, included questions on ciga- rette smoking in 1965,1966, 1970, 1974,1976,1977, 1978, 1979, and 1980. Information is routinely obtained on personal and demograph- ic characteristics. Questions focused primarily on such characteris- tics as present smoking status, amount smoked daily, and in more recent years, attempts to quit, and on tar and nicotine levels of cigarettes smoked. Information was not obtained on opinions, attitudes, or beliefs related to smoking. The universe for the NHIS is the civilian noninstitutionalized population of the United States. The survey is based on a multistage probability sample of primary sampling units in about 42,000 households containing about 85,000 persons. A one-third subsample of the adult respondents is interviewed for the smoking supplement (during 1965 and 1966 smoking data were obtained for all adults). Patterns of Smoking Prevalence and Cessation Prevalence of Cigarette Smoking The percentage of adults who report being current regular smokers, defined as persons who have smoked at least 100 cigarettes and who were smokers at the time of interview, has been declining steadily over the last _15 years (Table 1). For the total white male population, this decline has been from 51.3 percent in 1965 to 37.1 percent in 1980, and for white females, from 34.5 to 30.0 percent. Among black adults a similar pattern was seen-for males a decline from 59.6 to 44.9 percent, and for females, from 32.7 to 30.6 percent. Conversely, the percentage of the white adult male population who reported being former smokers increased between 1965 to 1980 from 21.2 to 31.9 percent, and of white females, from 8.5 to 16.3 percent by 1980. Again, a similar trend was observed among blacks, with the percentage of former smokers increasing from 12.6 to 20.6 percent of males, and from 5.9 to 11.8 percent of females. This increase in the percentage of former smokers is more marked among males (20.3 to 30.5 percent) than among females (8.2 to 15.7 percent), although the proportion among males increased by a factor of 1.5, while that among females doubled. In addition to this increase in percentage of former smokers over the E-year period, among most of the sex, race, and age groups there also appears to be an increase in the percentage of persons who 364 TABLE I.-Percentage distribution of adult current and former cigarette smokers, according to sex, race, and age, in 1965, 1976, and 1980 Current smoker' @wcent) Former smoker (percent) 1965 1976 1960' 1965 1976 1980= MALE Total 3.' All agea>m 20-2-i 2534 3544 45-64 t= White All ages>20' 20-24 25-34 3544 45-64 265 Black All agea>20" 20-24 2.534 3544 45-64 t= 52.1 41.6 37.9 20.3 29.6 30.5 59.2 45.9 36.7 9.0 12.2 12.1 60.7 46.5 43.1 14.7 18.3 20.6 58.2 47.6 42.6 20.6 27.3 27.6 51.9 41.3 40.8 24.1 37.1 36.9 28.5 23.0 17.9 28.1 44.4 47.4 51.3 41.0 37.1 21.2 30.7 31.9 56.1 46.3 39.0 9.6 13.3 12.2 60.1 47.7 42.0 15.5 18.9 21.9 57.3 46.8 42.4 21.5 28.9 28.8 51.3 46.6 40.0 25.1 36.1 38.4 27.7 22.8 16.6 26.7 45.6 50.1 59.6 50.1 44.9 12.6 20.2 20.6 67.4 52.8 45.5 3.8 4.1 10.6 68.4 59.4 52.0 6.7 11.8 11.9 67.3 59.8 44.2 12.3 13.8 21.2 57.9 49.7 46.8 15.3 26.6 26.3 36.4 26.4 27.9 21.5 33.0 26.6 34.2 32.5 29.8 a.2 13.9 15.7 41.9 34.2 32.7 7.3 10.4 11.0 43.7 37.5 31.6 9.9 12.9 14.4 43.7 38.2 34.9 9.6 15.6 18.9 32.0 34.8 30.8 8.6 15.9 17.1 9.6 12.8 16.6 4.5 11.7 14.2 34.5 32.4 Xl.0 8.5 14.6 16.3 41.9 34.4 33.3 8.0 11.4 12.5 43.4 37.1 31.6 10.3 13.7 14.7 43.9 38.1 35.6 9.9 17.0 20.2 32.7 34.7 30.6 8.B 16.4 17.4 9.8 13.2 17.4 4.5 11.5 14.3 32.7 34.7 30.6 5.9 10.2 11.6 44.2 34.9 32.3 2.5 5.0 2.2 47.6 42.5 34.2 6.7 8.9 11.6 42.0 41.3 36.5 7.0 9.6 12.5 26.7 36.1 34.3 6.6 11.9 14.1 7.1 9.2 9.4 4.5 13.3 14.1 ' A current smoker haa amoked at kast 100 eieustta, rod now smokea; includes -ional smokers. `Knalestimatas.Basedondarsforthe~Gmonthsofl~. J Bane of percentage excludea peraau with unknown smoking status. `lnCluded all other - not ohown rpuately. o A@z odjuntad by the direct me&cd to the 1970 civilian noninstitutionalized population using 5 age gn~~p. NOTE: Percentagea do not add up to 100 because of "never smoken" in the survey population. SOURCE: Data from the National He&h Interview Swvey, National Center for Health Statistics. 1965.1976. and 1960, baaed on household interviewa with a aample oftbe civilian noninstitutiioaalized population. report never having smoked. In males, this is demonstrated by both races and by the age groups younger than 45 years of age. In females, 365 TABLE 2.-Average number of cigarettes smoked per day by current and former smokers, by sex, age, and educational level, in 1970, 1975, and 1980 1970 ' 1975 ' 1980' Current Former Current Former Current Former smoker smoker emoker smoker smoker smoker Total Alla@ 221 Male All agea 221 21-24 25-34 3544 45-54 5544 2% Female Au ages 221 21-24 25-34 35-44 45-54 5544 265 Educational level o-8 9-11 12 13-15 216 20.0 22.6 21.2 24.5 21.7 25.0 21.8 25.0 22.8 n.2 23.4 28.1 20.8 16.2 18.9 20.8 19.4 18.7 21.0 23.4 22.1 24.0 22.1 24.0 23.0 27.7 23.4 28.0 25.6 28.7 24.2 25.4 W.l 29.5 27.2 31.6 21.6 n.7 25.0 28.1 23.3 31.3 17.2 25.3 20.3 28.0 20.9 n.1 17.7 17.3 19.1 18.8 19.7 19.8 16.1 13.8 18.6 14.7 17.8 17.6 18.1 16.7 18.5 17.7 19.4 20.3 18.6 18.2 20.1 19.5 22.5 19.8 18.4 19.0 20.3 20.8 20.7 22.4 17.0 15.4 19.0 20.8 20.0 20.4 14.0 14.6 16.1 17.1 15.6 17.2 18.1 20.3 20.2 20.3 20.8 d 21.7 21.7 25.9 20.5 26.2 22.2 21.6 25.0 22.3 n.a 22.8 20.8 24.2 21.9 24.4 22.5 21.3 25.1 22.1 24.3 23.2 20.6 22.1 21.1 24.0 ' National Survey on Adult Use of Tobacco. PHS. 1970. `National Health Interview Survey Smoking Supplement, PHS, 19&l. NOTE: Data from 1966 National Survey were not compatible with other years the increase in percentage of persons who report never having smoked is limited to the age groups younger than 35 years. Average Daily Consumption of Cigarettes Table 2 shows data on the average number of cigarettes smoked daily during three survey periods (1970, 1975, and 1980) for both current and former smokers. Overall, current smokers reported an increased consumption, from a mean of 20.0 cigarettes per day in 1970 to 21.7 cigarettes per day in 1980. The 1970 to 1980 increase in mean number of cigarettes smoked daily was slightly greater for females than for males (2.0 versus 1.2), a finding consistent with the increasingly similar smoking behavior in females and males. Thus, although males continue to smoke a greater average number of cigarettes per day than do females, the difference in daily consumption between the sexes for current smokers in 1980 was less than that observed a decade earlier. The heaviest daily consumption is observed in the middle-aged groups (35 to 64 years). A greater mean increase from 1970 to 1980 was observed among women aged 35 to 64. Male former smokers generally reported greater daily cigarette consumption than did current smokers in each survey. This trend was not found in females. This finding is contrary to the widely held belief that those who smoke fewer cigarettes per day are more likely to quit. It may be due in part to a tendency of former smokers to overestimate their consumption and of current smokers to underesti- mate their consumption or both. Among former smokers of both sexes, average daily consumption rates increased with age, peaking at the 45- to ELI-year-old age ~tegory. No trend over time is discernible by educational level in the overall mean daily consumption among current smokers. There was, however, an increase in the daily cigarette consumption of former smokers with 8 or fewer years of education, from 21.7 in 1970 to 26.2 in 1980. Within each survey year, there is also no discernible trend between level of education and daily cigarette consumption. The greater reported average daily consumption by educational status for former smokers than for current smokers may reflect cognitive dissonance, or changing social pressures that result in reporting bias. Table 3 displays the percentage distribution of current smokers by grouped number of cigarettes smoked daily, over the 1965,1976, and 1980 NHIS surveys. Cigarette smokers had a tendency to round off their reported number of cigarettes smoked per day (3) (Table 4). Approximately one-third of the smokers reported smoking exactly 20 cigarettes (one pack) a day in each of the survey years. The proportion of current smokers reporting consumption levels of 21 to 29 or 31 to 39 cigarettes per day remained relatively constant between 1970 and 1980. Although the proportion of smokers who report consumption levels of 20 to 39 cigarettes per day has remained fairly stable over the last 10 years (46.6 vs. 49.31, a clear difference is observed at the more extreme ends of the distribution, i.e., among those smoking fewer than 20 cigarettes and those smoking 40 or more cigarettes per hY- In 1970, only 11.4 percent of the respondents reported smoking 40 or more cigarettes per day; by 1980, 16.8 percent reported smoking 40 or more cigarettes per day. During the same period, smokers reporting consumption levels of less than 20 cigarettes per day decreased from 39.8 percent in 1970 to 33.8 percent in 1980 (Table 4). 367 TABLE 3.-Percentage distribution of adult current smokers' by grouped number of cigarettes smoked per day by sex, race, and age, 1965, 1976, and 1980 Ciittea smoked rer dav <15 15-24 225 Sex, race, and age 1965 1976 1930' 1965 1976 1960' 1965 1976 1960' MALE Total 3.' All ages>20 2&a 25-34 35-M 4544 L-65 white All ages>20 20-24 25-34 35-44 4564 >a Black All agee> 20-U 25-34 35-U 45-a >a FEMAJ.5 Total 3.' All ages>20 20-24 iE 45-64 >=J white All agee> 20-24 25-34 3544 45-64 t= Black All ages>20 2&24 2534 3544 4564 >a 28.3 24.2 23.1 46.3 44.8 42.7 25.4 31.0 34.1 34.9 31.6 32.0 49.1 49.9 47.8 15.4 18.5 20.2 25.1 25.5 23.6 50.0 45.8 46.5 24.3 28.7 29.9 23.7 19.6 15.8 44.8 41.2 42.3 31.5 39.2 41.9 26.7 18.5 21.6 45.3 44.1 36.4 28.0 37.4 42.0 47.1 39.1 29.2 39.0 42.7 46.1 13.8 16.2 24.7 25.9 21.4 19.1 46.8 44.9 43.6 27.4 33.7 37.4 32.3 27.5 27.1 50.8 62.8 50.4 16.9 19.7 22.4 22.8 22.1 19.5 51.1 46.5 41.4 26.1 31.4 33.1 21.3 17.2 12.8 44.6 40.4 42.1 33.9 42.5 45.1 24.6 16.2 17.3 45.4 43.3 37.4 30.0 40.4 45.3 44.6 37.5 26.1 40.3 42.2 46.2 15.1 20.4 27.7 48.1 43.8 46.7 42.6 44.0 40.3 9.3 52.7 56.9 66.6 41.9 34.2 36.7 5.3 47.8 46.0 44.4 41.7 43.5 46.2 10.5 42.5 38.5 45.6 45.5 44.8 41.1 12.0 46.9 35.9 51.1 43.7 50.8 35.0 9.4 64.9 53.0 41.1 31.9 47.0 47.2 3.2 11.5 8.9 10.5 16.7 13.3 10.9 6.8 9.6 13.2 14.1 11.1 43.6 36.5 34.2 42.2 43.8 42.0 14.2 19.6 23.7 48.4 43.1 42.0 41.9 42.4 41.1 9.7 14.5 16.1 41.4 34.3 33.5 43.1 45.2 41.9 15.5 20.5 24.6 39.1 33.8 27.8 43.7 44.4 39.3 17.1 21.8 33.0 44.4 34.3 29.8 42.0 44.2 45.9 13.6 21.5 24.2 62.6 4t3 48.9 31.0 38.9 37.7 6.4 11.8 13.4 41.0 33.2 30.6 43.9 45.2 4.8 15.1 21.6 25.6 45.3 39.3 37.4 44.4 44.3 44.1 10.4 16.4 18.5 37.9 30.6 28.6 45.4 46.8 44.9 16.7 22.6 26.5 36.2 29.5 24.6 45.3 45.4 39.9 16.4 25.1 35.5 42.4 32.0 26.4 43.2 45.1 47.0 14.5 23.0 25.9 61.5 45.7 46.1 31.8 41.7 37.7 6.8 12.6 14.2 67.7 60.0 61.1 26.4 73.4 65.7 78.0 22.1 66.2 58.8 61.9 25.1 63.4 60.4 555.6 30.4 69.4 53.2 53.8 26.9 63.2 loo.0 66.3 16.8 33.8 31.3 33.6 39.1 36.7 28.9 22.0 22.0 35.6 34.2 34.7 5.9 6.1 4.5 3.0 8.7 7.7 6.2 1.4 3.6 10.1 10.0 16.2 8.8 12.0 ' A current smoker has smoked at least 100 cigarettes and now amokeq include occasional smokers. ' Based on data for the last 6 months of 1980. *Base of percentage excludes unknown amount smoked. `Includes all -not shown seperate$. SOURCE: Data from the National Health Interview Survey. National Center for Health Statistics. 1965.1976, and 1980, based on household interviewa with a aample of the civilian noninstitutionaIized population. TABLE 4.-Percentage distribution of adult current smokers who reported smoking specific numbers of cigarettes per day, in 1970, 1975, and 1980 Percentage of current smokers Number of cigarettes/day 1970 ' 1975 ' 1980' l-9 15.8 13.5 13.1 39.81 37,O 1 33.81 l&19 24.0 23.5 20.7 20 34.9 32.0 34.8 21-29 3.1 2.8 2.3 30 9.6 12.1 11.5 31-39 1.0 0.8 0.7 40 8.8 10.7 11.1 11.41 15.2 1 16.8 1 41+ 2.6 4.5 5.7 ' National Survey on Adult Use of Tobecm. PHS, 1970 and 1975. ' Natiind Health Interview Survey Smoking Supplement, PHS W'reliminary). 1990. NOTE: Data from 1966 National Survey are not compatible with other yean. These findings may be due to several factors, including (1) increased smoking (possibly among those who have switched to lower tar cigarettes), (2) a higher cessation rate among persons smoking fewer cigarettes, (3) the entry of new smokers of greater numbers of cigarettes, or (4) some combination of these factors. Number of Attempts to Quit Smoking Survey data have shown that the majority of current smokers have made at least one serious but unsuccessful attempt to quit (4). Table 5 shows the percentage of current smokers who reported having made three or more attempts to quit. Similar data are shown for former smokers for two of the survey years. A modest downward trend is observed in the percentage of current smokers who reported making three or more attempts to quit (from 41.2 percent in 1966 to 38.7 percent in 1980), but the proportion of former smokers reporting three or more attempts to quit increased from 36.0 percent to 53.2 percent over the period from 1966 to 1975; this increase is seen in most of the sex, race, and age groups. Comparing the proportion of current smokers who had made three or more attempts to quit by years of education showed a general downward trend over time for all education levels except in the less than 8 years of education group, where the proportion increased from 38.9 percent in 1966 to 47.0 percent in 1980. Among the most educated current smokers, the decline was from 59.8 to 39.4 percent. TABLE S-Percentage of current and former smokers who made three or more attempts to quit, by sex, age, and educational level, in 1996, 1975, and 1980 1966' 1975 ' 1980' Current Former' Current Former' Current Former' smoker emoker smoker smoker smoker smoker All ages 221 41.2 36.0 40.5 53.2 30.7 Male All e&et3 221 21-24 2&34 3544 4l5-54 56-64 >_= 40.7 36.9 36.4 55.1 38.8 35.4 21.6 39.0 50.0 31.5 37.4 50.0 38.2 43.7 38.7 41.8 36.6 37.1 43.8 35.0 42.9 36.8 44.1 58.4 39.8 44.1 34.1 45.6 63.3 42.0 46.9 30.1 31.0 61.9 52.6 Female Allegw 221 21-24 2544 35-44 45-54 55-64 >a 41.5 34.0 42.0 49.1 38.7 28.6 35.3 32.3 52.9 31.3 34.5 36.1 39.5 47.2 31.0 43.5 33.3 45.1 42.7 42.5 56.7 23.9 44.0 57.0 37.1 36.6 43.6 44.7 50.9 49.2 43.5 28.6 46.9 46.4 46.1 Educational level o-6 9-11 12 13-15 216 38.9 32.3 44.3 42.7 30.0 40.8 36.4 36.2 40.0 37.7 _ 42.0 36.4 59.8 36.0 41.4 56.5 41.0 53.6 30.4 56.3 37.2 46.8 35.2 62.2 36.4 `National Survey on Adult Use 0fTobac.x~. PHS, 1966 and 1975. `National Health Interview Survey Smoking Supplement. PIiS fl'reliminary), 19&J. * Inclu&a the last s-ful attempt. o 1980 former lunoker data not availblc. Recent Attempt to Quit Data in Table 6 show the percentage of current and former smokers who reported an attempt to quit in the 12 months prior to the interview. Although there was little change overall from 1966 to 1975 in the percentage of current smokers who reported making an attempt to quit smoking in the previous year (1.5 percent), from 1975 to 1980 there was an increase of almost 10 percent. This increase is shown consistently for all the sex, race, and age groups. Among those who had attempted to quit, proportionately more young persons (under 35 years) than older persons reported attempting to quit during the previous 12 months. 370 TABLE 6.-Percentage of current and former smokers who attempted to quit during the last year, by sex, age, and educational level, in 1966, 1975, and 1966 sex, age. and education 1966' 1975 ' 1980' Current Former Current Former Current Former' smoker smoker smoker smoker smoker smoker Total Allegea 221 Male All ages 221 21-24 25-34 3644 u 5664 2-a Female Allages 221 21-24 26-34 3644 45-54 55-64 265 Edueationd level o-8 9-11 12 13-15 > 16 26.0 23.3 12.1 25.5 8.2 33.4 44.0 6.7 44.0 29.2 52.5 23.8 20.4 20.7 15.8 37.3 19.4 11.2 19.1 6.3 26.9 19.1 14.8 20.0 7.0 27.3 12.2 13.1 25.3 1.9 29.9 15.6 1.8 19.3 3.1 29.2 29.4 17.2 30.0 12.7 40.6 40.0 33.3 50.8 27.5 55.1 35.7 24.2 33.0 aI. 47.1 25.0 12.5 29.1 11.7 39.5 25.2 13.0 19.8 9.3 30.0 17.9 11.4 23.6 6.4 31.8 27.8 17.9 26.2 4.2 37.0 26.4 12.1 27.6 4.2 36.7 25.9 15.5 28.0 9.9 38.8 268 15.1 26.1 10.0 37.7 25.0 10.2 29.1 13.4 31.3 26.1 15.5 27.5 9.3 38.4 13.8 27.5 9.8 36.7 ' Nationni Survey on Adult Ua of Tobaax,, PEE?.. 19M aad 1976. *National Health Interview Survey Smoking Supplement, PISS (Reliminnry), 1980. * lseo former smoker da&i not ._vaileble. Relationship of Tar Yields to Smoking Behavior In 1972, the Public Health Service classified tar as one of the "most likely" contributors to the health hazards posed by cigarettes, and studies have confirmed its carcinogenicity (4). In response to this finding, a major change occurred in the cigarette products manufac- tured and actually used. Over the last two decades, the proportion of domestically consumed cigarettes yielding 15 mg or less of tar has increased from 15 percent in 1968 to 66.9 percent in 1981(7). The cigarette industry has also increased its promotional activities in marketing brands yielding 15 mg or less tar. The percentage of dollars expended in the United States on advertising and promotion of cigarettes yielding 15 mg or less tar has increased from 19.6 percent in 1975 to 48.1 percent in 1978. These factors may account, TABLE 7.-Percentage distribution of current regular smokers by tar level of primary brand of cigarettes, by sex and age, in 1975 and 1989 Sex and age 1975 ' 1980' Tar level Tar level <5 5-9 lo-14 15-19 2fJ+ <5 5-9 lo-14 15-19 20+ mg w mg mg mg w w me me mg Total All ages 221 0.8 0.6 9.5 67.9 20.2 6.3 13.1 26.4 44.0 10.4 Male AllageE 221 0.5 0.6 9.5 63.6 25.8 4.1 10.6 22.6 49.6 13.3 21-24 - - a.4 79.0 12.6 2.6 8.1 22.2 66.0 1.0 25-34 0.5 0.8 10.3 70.6 17.9 3.9 10.2 23.7 50.4 3.7 3544 1.1 0.2 8.5 65.8 24.4 3.8 10.9 25.3 45.0 14.9 45-54 - 0.5 12.1 56.1 31.3 5.0 10.1 22.2 39.0 23.6 55-64 1.2 1.6 8.5 50.2 38.5 5.4 11.6 19.6 39.8 23.6 t= 0.4 0.8 6.7 49.3 42.1 3.7 15.6 16.2 38.3 26.3 Female Au ages 221 1.1 0.6 11.7 73.2 13.4 8.9 15.9 28.7 39.4 7.1 21-24 1.2 0.3 11.7 80.4 6.4 5.5 8.5 32.5 51.9 1.7 25-34 0.6 0.4 10.9 78.4 9.7 6.7 18.9 28.9 44.5 0.9 35-44 1.2 0.9 13.0 74.6 10.3 13.6 15.2 29.1 37.1 5.1 4I5-54 1.5 0.3 10.8 65.6 21.9 8.1 17.8 29.9 32.5 11.7 55-64 0.8 - 12.6 70.3 16.3 9.7 13.7 24.2 37.6 14.9 $5 2.1 3.1 12.5 63.9 18.5 9.6 18.6 26.6 30.2 14.9 ' National Survey on Adult Use of Tolmcco, PHS, 1975. ' National Health Interview Survey Smoking Supplement, PIiS (preliminary). 1980. in part, for the ever-in&easing use by current smokers of lower tar cigarettes. The definition of cigarettes as "lower tar" at 15 mg is arbitrary. Nonetheless, this breakpoint has gained general acceptance. Special note should be taken, however, that tar yields vary continuously, and groupings by relative yield measurements do not automatically imply differences in either the type or the magnitude of their biological effects. The percentage distribution of current regular smokers by tar level of their primary brand of cigarette is presented in Table 8. A clear trend toward increased use of lower tar products is apparent. The 1975 data on brands were coded to the 1975 Federal Trade Commission (FTC) values for tar yield, and the 1980 data were coded to the 1979 FTC values. As tar values have bean progressively declining, the 1980 data probably represent slightly higher values of tar yields than were actually being used at that time. Conclusions 1. The proportion of current regular smokers declined steadily between 1965 and 1980. The decline was steeper among males (from 52.1 to 37.9 percent) than among females (from 34.2 to 29.8 percent). 2. The proportion of never smokers increased steadily from 1965 to 1980 among males (27.6 to 31.6 percent), except those 45 years old and older. Among females, only 20- to 34-year-olds showed an increase in proportion of never smokers. 3. The mean number of cigarettes smoked per day by current smokers increased slightly from 1970 to 1980 (from 20 to 21.7 cigarettes). 4. Males smoked a higher mean number of cigarettes throughout the 1970-1980 period, but the number for males and females increased about the same amount. 5. Heaviest daily consumption was in the middle-aged group (35- 65 years). The greatest mean increase was observed among women aged 35 to 44. 6. The proportion of current smokers who smoked less than 20 cigarettes per day decreased between 1970 and 1980 (39.8 to 33.8 percent); the proportion smoking one pack exactly (20 cigarettes) remained constant (34.9 to 34.8 percent); the propor- tion smoking from 21 to 39 cigarettes increased slightly (13.7 to 14.5 percent); and the proportion smoking two or more packs per day increased (11.4 to 16.8 percent). 7. The proportion of current smokers who attempted to quit three or more times decreased slightly from 1966 to 1980 (41.2 to 38.7 percent). 8. The proportion of former smokers having made three or more attempts to quit increased sharply (36 to 53.2 percent) from 1966 to 1975. 9. The proportion of current smokers who had attempted to quit during the past year increased from 1966 to 1980 (26.0 to 36.7 percent). 10. Among current smokers, younger persons and females were more likely than older persons and males to have attempted to quit during the previous 12 months. 11. The proportion of former smokers who had attempted to quit during the previous 12 months decreased from 1966 to 1975 (13.8 to 9.8 percent). 12. Among former smokers, younger persons and females were more likely than older persons and males to have quit during the previous 12 months. References (I) MAXWELL, J.C., Jr. Maxwell estimates 1981 cigarette s&a up 2.6 percent. United Stutea Tolxxco JournuI209@3-24): 1,6,8,50, December 6-22, 1961. (2) NATIONAL CENTER FOR HEALTH STATISTICS. He&h, United States, 1981. U.S. Department of Health and Human Services, Public Health Service, National Center for Health Statistics, National Center for Health Services Research, DHHS Publication No. (PHS)&X?+1232, December 1981, 337 PP. (3) U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES. The Changing Cigarette: A Report of the Surgeon Gxeml. U.S. Department of Health and Human Services, Public Health Service, Ofke of the Aseietant Secretary for Health, Office on Smoking and Health, DHHS Publication No. @VIS)61- !50156,1981,262 pp. (4,I U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE. Smoking and Health: A Report of the Surgeon General. U.S. Department of Health, Education, and Welfare. Public Health Service, Of&e of the Ae&tant Secretary for Health, Office on Smoking and Health, DHEW Publication No. @`HS)7940066,1979,1136 pp. (5) U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE. The Health C~nwquencea of Smoking for Worn... A Report of the Surgeon Ceneml. U.S. Department of Health, Education, and Welfare, Public Health Service, Office of the Assistant Secretary for Health, Oftice on Smoking and Health, 1960,359 pp. (6) U.S. PUBLIC HEALTH SERVICE. Use of Tobacco, Pm&ices, Attitudes, KmwMge, wuf Beliefs, United States: Fall 1964 and Spring 1966. U.S. Department of Health, Education, and Welfare, National clearinghouse for Smoking and Health, July 1969,607 pp. (7) U.S. PUBLIC HEALTH SERVICE. Adult Use of Tobacco, 1970. U.S. Depart- ment of Heakh, Education, and Welfare, Public Health Service, Center for Disease Control, National Clearinghouse for Smoking and Health, DHEW Publication No. (I-ISMj73-6727, June 1973,129 pp. (8) U.S. PUBLIC HEALTH SERVICE. Adult Use of Tobacco, 1975. U.S. Depart- ment of Health, Education, and Welfare, Public Health Service, Center for Diseaee Control. National clearinghouse for Smoking and Health, June 1976.