Comparison of risk profiles for new-onset atrial fibrillation between patients aged <60 and ≥60 years

BACKGROUND: Atrial fibrillation (AF) has a heterogeneous pathophysiology according to individual patient characteristics. This study aimed to identify the effects of widely known risk factors on AF incidence according to age and to elucidate the clinical implications of these effects. METHODS AND RESULTS: We analyzed data from 501,668 subjects (≥18years old) without AF and valvular heart disease from the Korean National Health Insurance Service-National Sample Cohort. The total population was divided into two groups according to age, <60years and ≥60years. AF occurred in 0.7% of the overall population (3,416 of 501,668) during the follow-up period (mean 47.6 months). In Cox regression analysis, age, male sex, previous ischemic stroke, heart failure, and hypertension were related to increased risk of new-onset AF in both age groups. Especially in the <60years age group, risk of new-onset AF was increased by relatively modifiable risk factors: obesity (body mass index ≥25kg/m(2); hazard ratio[HR] 1.37 [1.22–1.55], p<0.001, interaction p<0.001), and hypertension (HR 1.93[1.69–2.22], p<0.001, interaction p<0.001). Although interactions were not significant, chronic obstructive pulmonary disease (HR 1.41[1.24–1.60], p<0.001) and chronic kidney disease (HR 1.28[1.15–1.41], p<0.001) showed increased trends of the risk of new-onset AF in the ≥60years age group. CONCLUSION: The risk profile for new-onset AF was somewhat different between the <60years and the ≥60years age groups. Compared to the ≥60years group, relatively modifiable risk factors (such as obesity and hypertension) had a greater impact on AF incidence in the <60years age group. Different management strategies to prevent AF development according to age may be needed.