(●◆■▲, no adjustment; ○□▵, adjusted for smoking) The confidence interval of the estimate among men never smokers is (0.39 to 8.99). All analyses are stratified for age at baseline and center. Among current smokers, the model includes age at starting (continuous), duration of smoking (continuous in years), current quantity (continuous), a quadratic term for current quantity, two interaction terms (quantity × duration and age at starting × duration). Among ex-smokers, the model includes age at starting (continuous), duration of smoking (continuous in years), and one interaction term (age at starting × duration).