Age dependence of risk factors for stroke and death in young patients with atrial fibrillation: a nationwide study

Abstract

Background and purpose: The risk of stroke and death in patients with atrial fibrillation is strongly associated with age and concomitant comorbidities. The aim of this study was to examine the age dependence of risk factors for stroke and mortality in young patients with atrial fibrillation.

Methods: This study is a population-based cohort study of 30- to 65-year-old patients with atrial fibrillation and diagnosed during 2000 to 2011, identified by record linkage between nationwide Danish registries. Cox regression models were used to estimate the risk of stroke and mortality according to risk factors within age groups: 30 to 50, 50 to 65, and 65 to 75 years.

Results: We identified 73,799 nonvalvular atrial fibrillation patients, of which 37,782 (51.2%) were <65 years old (mean age 62.8). A higher modified cardiac failure or dysfunction, hypertension, age 75 (doubled), diabetes, stroke (doubled), vascular disease, age 65-74 and sex category (female) score (CHA2DS2-VASc score) was associated with decreased survival probability in all age groups. The overall incidence of stroke per year for 1 year (5 years) follow-up was 1.2% (0.6%), 3.5% (1.6%), and 5.6% (2.8%), respectively, for the age groups of 30 to 50, 50 to 65, and 65 to 75. Overall, risk factors such as previous stroke, heart failure, vascular disease, diabetes mellitus, and hypertension remained independent predictors of stroke and death in patients<65 years old with nonvalvular atrial fibrillation.

Conclusions: The CHA2DS2-VASc score is an applicable tool for all age groups and in nonvalvular atrial fibrillation patients<65 years old, the same risk factors apply.

Keywords: atrial fibrillation; death; risk factors; stroke.