Atrial fibrillation (AF) is linked to heart failure (HF). However, little has been published on the factors that may precipitate the onset of HF in AF patients. We aimed to determine the incidence, predictors, and prognosis of incident HF in older patients with AF with no prior history of HF.

Patients with AF older than 80 years and without prior HF were identified between 2014 and 2018.

A total of 5794 patients (mean age, 85.2±3.8 years; 63.2% women) were followed up for 3.7 years. Incident HF, predominantly with preserved left ventricular ejection fraction, developed in 33.3% (incidence rate, 11.5-100 people-year). Multivariate analysis identified 11 clinical risk factors for incident HF, irrespective of HF subtype: significant valvular heart disease (HR, 1.99; 95%CI, 1.73-2.28), reduced baseline left ventricular ejection fraction (HR, 1.92; 95%CI, 1.68-2.19), chronic pulmonary obstructive disease (HR, 1.59; 95%CI, 1.40-1.82), enlarged left atrium (HR 1.47, 95%CI 1.33-1.62), renal dysfunction (HR 1.36, 95%CI 1.24-1.49), malnutrition (HR, 1.33; 95%CI, 1.21-1.46), anemia (HR, 1.30; 95%CI, 1.17-1.44), permanent AF (HR, 1.15; 95%CI, 1.03-1.28), diabetes mellitus (HR, 1.13; 95%CI, 1.01-1.27), age per year (HR, 1.04; 95%CI, 1.02-1.05), and high body mass index for each kg/m2 (HR, 1.03; 95%CI, 1.02-1.04). The presence of incident HF nearly doubled the mortality risk (HR, 1.67; 95%CI, 1.53-1.81).

The presence of HF in this cohort was relatively frequent and nearly doubled the mortality risk. Eleven risk factors for HF were identified, expanding the scope for primary prevention among elderly patients with AF.