Cigarette smoking and competing risks for fatal and nonfatal cardiovascular disease subtypes across the life course

BACKGROUND: Cigarette smoking is significantly associated with premature death related and not related to cardiovascular disease (CVD). Whether risk associated with smoking is similar across CVD subtypes and how this translates into years of life lost is not known. METHODS AND RESULTS: We pooled and harmonized individual-level data from 9 population-based cohorts in the United States. All participants were free of clinical CVD at baseline with available data on current smoking status, covariates, and CVD outcomes. We examined the association between smoking status and total CVD and CVD subtypes, including fatal and nonfatal coronary heart disease, stroke, congestive heart failure, and other CVD deaths. We performed (1) modified Kaplan– Meier analysis to estimate long-term risks, (2) adjusted competing Cox models to estimate joint cumulative risks for CVD or noncardiovascular death, and (3) Irwin’s restricted mean to estimate years lived free from and with CVD. Of 106 165 adults, 50.4% were women. Overall long-term risks for CVD events were 46.0% (95% CI, 44.7– 47.3) and 34.7% (95% CI, 33.3– 36.0) in middle-aged men and women, respectively. In middle-aged men who reported smoking compared with those who did not smoke, competing hazard ratios (HRs) were higher for the first presentation being a fatal CVD event (HR, 1.79 [95% CI, 1.68– 1.92]), with a similar pattern among women (HR,1.82 [95% CI, 1.68–1.98]). Smoking was associated with earlier CVD onset by 5.1 and 3.8 years in men and women. Similar patterns were observed in younger and older adults.