Abstract
AIMS: Atrial fibrillation (AF) and heart failure (HF) often coexist. Older age is strongly associated with stroke, HF, and mortality. The association between coexistence of HF and a risk of clinical outcomes and the effectiveness of anticoagulation therapy including direct oral anticoagulants (DOACs) in elderly patients with AF and HF have not been investigated. We aimed to evaluate 2 years of outcomes and to elucidate the efficacy of DOACs or warfarin in elderly AF patients in the All Nippon AF In the Elderly (ANAFIE) Registry with and without a history of HF. METHODS AND RESULTS: The ANAFIE Registry is a multicentre, prospective observational study following elderly non-valvular AF patients aged ≥75 years for 2 years. Hazard ratios (HRs) were calculated based on the presence or absence of an HF diagnosis and DOAC or warfarin use at enrolment. Among 32 275 eligible patients, 12 116 (37.5%) had been diagnosed with HF. Patients with HF had significantly higher rates of HF hospitalization or cardiovascular death (HR 1.94, P < 0.001), cardiovascular events (HR 1.59, P < 0.001), cardiovascular death (HR 1.49, P < 0.001), all-cause death (HR 1.32, P < 0.001), and net clinical outcome including stroke/systemic embolism, major bleeding, and all-cause death (HR 1.23, P < 0.001), compared with those without HF; however, HRs for stroke/systemic embolism (HR 0.96, P = 0.56) and major bleeding (HR 1.14, P = 0.13) were similar. DOAC use was associated with a low risk of stroke/systemic embolism (HR 0.86, P = 0.19 in HF; HR 0.79, P = 0.016 in non-HF; P for interaction = 0.56), major bleeding (HR 0.71, P = 0.008 in HF; HR 0.75, P = 0.016 in non-HF; P for interaction = 0.74), HF hospitalization or cardiovascular death (HR 0.81, P < 0.001 in HF; HR 0.78, P < 0.001 in non-HF; P for interaction = 0.26), cardiovascular events (HR 0.83, P < 0.001 in HF; HR 0.82, P = 0.001 in non-HF; P for interaction = 0.65), cardiovascular death (HR 0.84, P = 0.12 in HF; HR 0.75, P = 0.035 in non-HF; P for interaction = 0.18), all-cause death (HR 0.89, P = 0.082 in HF; HR 0.80, P = 0.001 in non-HF; P for interaction = 0.091), and net clinical outcome (HR 0.88, P = 0.019 in HF; HR 0.81, P < 0.001 in non-HF; P for interaction = 0.21) compared with warfarin, irrespective of the presence or absence of HF. Analysis using the propensity score matching method showed similar associations. CONCLUSIONS: Non-valvular AF patients aged ≥75 years with a history of HF had higher risks of cardiovascular events and mortality. DOACs were favourable to warfarin regardless of the coexistence of HF. These results might encourage the use of DOACs in elderly patients with non-valvular AF with or without HF.