Frailty as a Risk Factor for Cardiovascular Versus Noncardiovascular Mortality in Older Men: Results From the MrOS Sleep (Outcomes of Sleep Disorders in Older Men) Study

BACKGROUND: Frailty is associated with greater mortality; however, whether frail patients primarily die of cardiovascular disease (CVD) or non‐CVD causes is unknown. METHODS AND RESULTS: We assessed the cause of death in relation to frailty status, measured at baseline, among 3135 community‐dwelling older men in the MrOS Sleep (Outcomes of Sleep Disorders in Older Men) study. Absolute probability and risk of CVD mortality associated with frailty status were estimated with traditional methods that used censoring and newer methods that considered non‐CVD mortality as a competing risk. Of the 3135 men (mean age: 76.4±5.6 years), 475 (15.2%) were frail. During an average follow‐up of 9.2 years, 1275 (40.7%) men died, including 445 (34.9%) from CVD and 828 (64.9%) from non‐CVD causes (2 deaths unadjudicated). Both CVD and non‐CVD mortality risk increased with frailty. Cumulative absolute probability of CVD death at 10 years among frail men was 23.8% (20.2–27.6%) using the competing risk method versus 32.5% (27.3–37.8%) using the traditional Kaplan–Meier method (41.5% [95% confidence interval, 36.9–45.9%] and 48.6% [95% confidence interval, 43.6–53.4%], respectively, for non‐CVD mortality). The multivariable‐adjusted risk of CVD death among frail versus robust men was 1.38 (95% confidence interval, 0.99–1.92) using the competing risk method versus 1.84 (95% confidence interval, 1.35–2.51) using the traditional Cox proportional hazards method. CONCLUSIONS: Among community‐dwelling older men, ≈35% of the deaths were due to CVD. Frail men were at increased risk of CVD death, but ignoring the competing risk of non‐CVD mortality overestimated their long‐term probability and relative risk of CVD death.