Smoking and risk of fatal prostate cancer in a prospective U.S. study.

OBJECTIVES

To examine the association of cigarette smoking with subsequent fatal prostate cancer.

METHODS

Two private censuses were conducted in Washington County, Maryland, in which 26,810 adult men in 1963 and 28,292 in 1975 provided smoking information. Prostate cancer deaths through 2000 (1963 cohort, 240 deaths; and 1975 cohort, 184 deaths) were ascertained by review of the death certificates. Poisson regression analysis was used to estimate the rate ratio of prostate cancer death adjusted for age.

RESULTS

Overall, cigarette smokers in the 1963 census cohort were not more likely to die of prostate cancer than those who had never smoked cigarettes, pipes, or cigars when considering the total follow-up period. However, current smokers of 20 or more cigarettes per day (rate ratio 2.38; 95% confidence interval 0.94 to 5.99) and former smokers (rate ratio 2.75; 95% confidence interval 1.13 to 6.74) had a greater risk of death from prostate cancer during the first 10 years of follow-up. Weaker positive associations of prostate cancer death with current and former cigarette smoking were seen during the first 10 years of follow-up in the 1975 census cohort. Current cigarette smoking at baseline was not associated with the prostate cancer incidence.

CONCLUSIONS

The lack of an association between cigarette smoking and prostate cancer incidence, but the tendency of greater prostate cancer mortality in former and current cigarette smokers earlier in the follow-up period is consistent with other studies in which smoking was assessed once at baseline.