Cause of Death and Associated Factors in Elderly Patients With Atrial Fibrillation　― Long-Term Retrospective Study ―

Background Oral anticoagulant (OAC) therapy reduces the risk of stroke in patients with atrial fibrillation (AF). This study elucidated the causes of death and related factors in elderly Japanese AF patients. Methods and Results Over a median (interquartile range [IQR]) follow-up period of 46 (20–76) months, there were 171 all-cause deaths (28% cardiovascular, 46% non-cardiovascular, and 26% unknown causes) among 389 AF patients (median [IQR] age 80 [74–85] years; CHAD2DS2-VASc score 5 [4–6]). Cox regression analysis indicated that diabetes was associated with an increase in all-cause death (hazard ratio [HR] 1.48; 95% confidence interval [CI] 1.02–2.13), whereas hypercholesterolemia (HR 0.53; 95% CI 0.35–0.79), pre-existing heart failure (HR 0.67; 95% CI 0.48–0.95), and OAC use (HR 0.62; 95% CI 0.44–0.88) were associated with reductions in all-cause death. Pre-existing heart failure was associated with both cardiovascular (HR 3.03; 95% CI 1.33–8.20) and non-cardiovascular (HR 0.44; 95% CI 0.30–0.65) deaths, in opposite directions. OAC use was associated with a reduction in cardiovascular death (HR 0.34, 95% CI 0.17–0.69). The predominance of non-cardiovascular death and death-related factors were equivalent regardless of when observations started (before 2009 or in 2009 and later). Conclusions The predominant cause of death in elderly Japanese AF patients was non-cardiovascular. Distinct clinical factors were associated with cardiovascular and non-cardiovascular death.