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the major risk factors for heart disease. In general, then, the 1990 ob- jectives concerning the population's knowledge of the health consequences of cigarette smoking have been met.

2. EPIDEMIOLOGY AND ETIOLOGY

Southwestern Internal Medicine Conference: Cigarette Smoking and Lung Disease. Vial, W.C. Pulmonary Section, Dallas Veterans Administration Medical Center, Dallas, TX, U.S.A. Am. J. Med. Sci. 291: 130-142, 1986.

Despite major changes in the pat- terns of cigarette consumption in the United States in the last two decades, cigarette smoking remains a widespread practice. Many studies show a strong association between cigarette smoking and chronic obstructive lung disease, but only recently have mechanisms been elucidated to explain this association, particularly in the case of emphysema. The exact mechanism of chronic bron- chitis is less well defined. The mor- tality rate for lung cancer continues to increase in this country, par- ticularly among women. Compelling evidence associates lung cancer with cigarette smoking, although animal models have not been very successful. Recently, concern has been raised about the effects of passive smoking. There are substantial data available to sug- gest that passive smoking results in pulmonary infections and abnormal pul- monary function in children of smokers. The data are less clear-cut for pulmo- nary functional impairment in adults and for lung cancer in the spouses of smokers. Although the concept of 'safer' cigarettes has been widely ac- cepted by the American public, these cigarettes may not be as safe as is widely assumed. Clearly, they are far inferior to total smoking cessation. Nevertheless, smoking cessation remains difficult for many Americans, despite a number of methods that have been used to help smokers quit. Nicotine chewing gum, which has recently become avail- able for use in the United States, has shown some efficacy in helping well- motivated, nicotine-dependent smokers quit smoking. Although some inroads have been made into the occurrence of smoking related diseases in the United States, many unnecessary deaths con- tinue to occur.

Diet and Lung Cancer Risk: Findings from the Western New York Diet Study. Byers, T.E., Graham, S., Haughey, B.P. et al. Department of Social and Preven- tive Medicine, School of Medicine, State University of New York at Buffalo, Buffalo, NY 14214, U.S.A. Am. J. Epidemiol. 125: 351-363, 1987.

This study compares the diets of 450 lung cancer cases (296 males, 154 females) with those of 902 controls (587 males, 315 females). Cases were lung cancer patients diagnosed between August 1980 and July 1984 in three western New York countries, while con- trols were selected from the general population of these same counties. Usual diet was estimated by detailed interviews using a modified food frequency method. Case-control com- parisons were made for dietary fat, protein, fiber, calories, cholesterol, and vitamins A, C, and E according to quartiles of intake, adjusting for age and pack-years of cigarettes by mul- tiple logistic regression. Risk was lower for males in the lowest quartile of total dietary fat intake compared with those in the highest quartile (relative risk = 0.5), although the overall trend in the association with dietary fat was not statistically sig- nificant (p = 0.12). Likewise, there was a weak, but not statistically significant, direct association between dieteray cholesterol and lung cancer in men (p = 0.17). The intake of vitamin A from fruits and vegetables (carotene) was much more strongly associated with reduced cancer risk. For males, the relative risks by quartiles (lowest in- take to highest intake) were 1.8, 1.8, 1.0, 1.0 (p for trend = 0.001). For females, this relation was considerably weaker, and was not statistically significant. These findings are generally in agreement with those of several previous studies. The risk reduction associated with vitamin A from fruits and vegatables (carotene) was most evident for males, for those with squamous cell cancers, for light or ex-smokers, and for those over 60 years of age.

Serum Beta-Carotene, Vitamin A and E, Selenium, and the Risk of Lung Cancer. Menkes, M.S., Comstock, G.W., Vuilleumier, J.P. et al. Department of Epidemiology, Johns Hopkins School of Hygiene and Public Health, Baltimore, MD, U.S.A. New. Engl. J. Med. 315: 1250-1254, 1986.

We studied the relation of serum vitamin A (retinol), beta-carotene, vitamin E, and selenium to the risk of lung cancer, using serum that had been collected during a large blood- collection study performed in Washington County, Maryland, in 1974. Levels of the nutrients in serum samples from 99 persons who were sub- sequently found to have lung cancer (in 1975 to 1983) were compared with levels in 196 controls who were matched for age, sex, race, month of blood donation, and smoking history. A strong inverse association between serum beta-

carotene and the risk of squamous-cell carcinoma of the lung was observed (relative odds, 4.30; 95 per cent con- fidence limits, 1.38 and 13.41). Mean (+ or - SD) levels of vitamin E were lower among the cases than the controls (10.5 + or - 3.2 vs. 11.9 + or - 4.90 mg per liter), when all histologic types of cancer were considered together. In addition, a linear trend in risk was found (P = 0.04), so that persons with serum levels of vitamin E in the lowest quintile had a 2.5 times higher risk of lung cancer than persons with levels in the highest quintile. These data support an association be- tween low levels of serum vitamin E and the risk of any type of lung cancer and between low levels of serum beta- carotene and the risk of squamous-cell carcinoma of the lung.

Indoor Exposure to Radon from the Group and Bronchial Cancer in Women. Svensson, C., Eklund, G., Pershagen, G. Department of Cancer Epidemiology, Radiumhemmet, Karolinska Institute, S- 104 01 Stockholm, Sweden. Int. Arch. Occup. Environ. Health 59: 123-131, 1987.

A case-referent study on the pos- sible association between radon emanat- ing from the group and bronchial cancer was carried out on 292 female lung can- cer cases and 584 matched population referents. Both groups had lived for at least 30 years in the city of Stockholm, Sweden. The cases were diag- nosed during 1972 to 1980 with oat-cell and other types of anaplastic pulmonary carcinomas. A sample of about 10% of the dwellings where cases and referents had lived was selected for measurements of radon and radon daughters. There was a relative risk of 2.2 (P = 0.01) for lung cancer associated with living in dwellings close to the ground in areas with an increased risk of radon emanation. Smoking habits did not ap- pear to be a major confounding factor for this association, although a detailed evaluation was not possible. The measurements indicated increased radon daughter concentrations in ground level dwellings within radonrisk areas where lung cancer cases had lived, sug- gesting that this exposure was of etiologic importance.

Lung Cancer and Women: Results of a French Case-Control Study. Benhamou, E., Benhamou, S., Flamant, R. Departement de Statistique Medicale, Institute Gustave Roussy, 94805 Vil- lejuif Cedex, France. Br. J. Cancer 55: 91-95, 1987.

Ninety-six women with histologi- cally confirmed lung cancer and 192 matched controls were involved in an international case-control study con-

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ducted from 1976 to 1980. The aim of this study was an examination of the effects of different smoking habits, especially the type of cigarettes smoked (light or dark tobacco and fil- ter or nonfilter use) on the occurrence of lung cancer in French females. All these patients were either nonsmokers or lifetime cigarette smokers. Matched relative risk (RR) of smokers compared to nonsmokers was found to be increased for both Kreyberg I (RR = 6.6) and Kreyberg II (RR = 2.1) categories; however, this increase was significant (P < 0.0001) only for Kreyberg I lung cancer. A significant increase (P < 0.0001) in matched RR was found with early age at first cigarette smoked, daily consumption, duration of smoking, frequency of inhalation, use of dark tobacco and use of nonfilter cigarettes. Matched RR associated with smokers not always using dark tobacco and those smoking only dark tobacco as compared to nonsmokers were sig- nificantly increased (trend test P < 0.0001). On the contrary, the increase of RR was not significant when either daily consumption, or duration of smoking, or age at first cigarette was taken into account. Lung cancer ap- peared to be associated with daily con- sumption and use of nonfilter cigarettes in a matched logistic regression. Risk Factors for Adenocarcinoma of the Lung. Brownson, R.C., Reif, J.S., Keefe, T.J. et al. Cancer Epidemiology and Control Program, Division of Environmental Health and Epidemiology Services, Mis- souri Department of Health, P.O. Box 1268, Columbia, MO 65205, U.S.A. Am. J. Epidemiol. 125: 25-34, 1987.

The relation between various risk factors and adenocarcinoma of the lung was evaluated in a case-control study. Subjects were selected from the Colorado Central Cancer Registry from 1979-1982 in the Denver metropolitan area. A total of 102 (50 males and 52 females) adenocarcinoma case interviews and 131 (65 males and 66 females) con- trol interviews were completed. The control group consisted of persons with cancers of the colon and bone marrow. The risk estimates associated with cigarette smoking were significantly elevated among males (odds ratio (OR) = 4.49) and females (OR = 3.95) and were found to increase significantly (p < 0.01) with increasing levels of cigarette smoking for both males and females. For adenocarcinoma in females, the age- and smoking-adjusted odds ratios at different levels of passive smoke exposure followed an increasing overall trend (p = 0.05). After addi- tional adjustment for potential