Incidence of atrial fibrillation in elderly patients with type 2 diabetes mellitus

Introduction The incidence of atrial fibrillation (AF), a significant risk factor for cardiovascular disease (CVD), is increasing worldwide. Type 2 diabetes mellitus (T2D) and advanced age are recognized as major risk factors for AF, but herein, we evaluated the incidence of AF in elderly patients with T2D and compared the prognosis between these patients with/without AF. Research design and methods The Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD2) study is a follow-up cohort study of the JPAD trial, a randomized controlled clinical trial initiated in 2002 in 2535 Japanese patients with T2D, to examine whether low-dose aspirin prevents CVD. After completion of that trial, we followed up the patients until 2019 and evaluated the incidence of AF. We also compared the incidence of cerebral cardiovascular events in elderly patients with T2D with/without AF. Results During the median follow-up period of 10.9 years, 132 patients developed AF (incidence rate: 5.14/1000 person-years). The adjusted HRs for cerebral cardiovascular events, stroke, coronary artery disease, heart failure, and all-cause death in elderly patients with T2D with versus without AF were 1.65 (95% CI 1.03 to 2.66), 1.54 (95% CI 0.81 to 2.93), 1.96 (95% CI 1.03 to 3.73), 5.17 (95% CI 2.46 to 10.89), and 1.82 (95% CI 1.24 to 2.67), respectively. Conclusions Annually, 1 in 200 elderly Japanese patients with T2D are estimated to develop AF. Because elderly patients with T2D with AF are at an elevated risk for CVD, careful follow-up of this patient subgroup is necessary.