Cigarette smoking: an independent risk factor for impotence?

The authors sought to determine whether current cigarette smoking was associated with impotence among middle-aged men. This is a secondary analysis of a cross-sectional survey of 4,462 US Army Vietnam-era veterans aged 31-49 years who took part in the Vietnam Experience Study in 1985-1986. The main outcome measurement was the odds ratio for reported impotence, which was calculated by comparing current smokers with nonsmokers while controlling for multiple confounders. The study sample consisted of 1,162 never smokers, 1,292 former smokers, and 2,008 current smokers. The prevalence of impotence was 2.2% among never smokers, 2.0% among former smokers, and 3.7% among current smokers (p = 0.005). The unadjusted odds ratio (OR) of the association between smoking and reported impotence was 1.8 (95% confidence interval (CI) 1.2-2.6). The association held even after adjustments were made for confounders, including vascular disease, psychiatric disease, hormonal factors, substance abuse, marital status, race, and age (OR = 1.5, 95% CI 1.0-2.2). Neither years smoked nor cigarettes smoked daily were significant predictors of impotence in current smokers. The authors concluded that, among the men in this study, a higher percentage of cigarette smokers reported impotence than did nonsmokers. This observation could not be totally explained by comorbidity factors related to smoking.