Real-world clinical outcomes and anticoagulant therapy in elderly non-valvular atrial fibrillation patients with heart failure: sub-analysis of the ANAFIE Registry
Authors: Ikeda S , Hiasa K , Tsutsui H ,   ANAFIE Registry Group
Published: October 2021

Abstract

Background
Atrial fibrillation (AF) and heart failure (HF) are bidirectionally correlated; the more severe the NYHA classification, the higher the incidence rate of atrial fibrillation, and vice versa. HF is included in the items of CHA2DS2-VASc score used to calculate stroke risk in patients with AF, and is itself a risk factor for thromboembolism in such patients. Anticoagulant management in AF patients with HF is thus a key concern that remains to be sufficiently examined, especially in elderly patients aged ≥75 y.

Purpose
The All Nippon Atrial Fibrillation In the Elderly (ANAFIE) Registry enrolled more than 30,000 elderly (≥75 y) patients with non-valvular AF (NVAF), aiming to produce real-world data on their clinical status and prognosis. This sub-analysis of the ANAFIE Registry assessed the 2-year outcomes and status of anticoagulant treatment in elderly NVAF patients with HF.

Methods
A total of 32,275 patients from the ANAFIE Registry were divided into two groups according to whether they had HF (HF group and reference group). The incidence rates and adjusted hazard ratios (HR) of clinical outcomes were determined using Kaplan-Meier analysis and the Cox proportional-hazards model, respectively.

Results
A total of 20,159 (62.5%) patients were included in the reference group, and 12,116 (37.5%) in the HF group. Compared with the reference group, the HF group had higher mean age (82.4 vs 80.9 y), female ratio (46.6% vs 40.4%), non-paroxysmal AF (69.8% vs 50.8%), and had lower mean CrCL (43.3 vs 51.6 mL/min). In the HF group, the rate control drugs were frequently used (50.1% vs 35.8%), and the rhythm control drugs were less used (14.2% vs 22.7%) than in the reference group. More patients in the HF group were using anticoagulants (93.9% vs 91.6%; warfarin (WF), 29.6% vs 23.0%; direct oral anticoagulants (DOAC), 64.2% vs 68.5%) than those in the reference group. The HF group had a numerically higher incidence of stroke or systemic embolic events (SEE) (3.28% vs 2.84%, HR 0.96, p=0.558) and major bleeding (2.35% vs 1.79%, HR 1.14, p=0.130) than the reference group, but the differences were not statistically significant. The HF group had a significantly higher incidence rate of HF requiring hospitalization (12.99% vs 4.59%, HR 1.94, p&lt;0.001) and all-cause mortality (9.83% vs 5.21%, HR 1.32, p&lt;0.001). In the HF group, patients receiving DOAC had significantly lower incidence rates for major bleeding, HF requiring hospitalization, and all-cause mortality than those receiving WF, while there was no difference for stroke/SEE between both groups.

Conclusions
Elderly NVAF patients with HF had higher risk of HF requiring hospitalization and mortality than those without. Differences were seen in the incidence rates of major bleeding, HF requiring hospitalization, and all-cause mortality between patients on DOAC and those on WF. This study will explore relevant factors affecting clinical outcomes in elderly NVAF patients with HF.

Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Daiichi Sankyo Co., Ltd.