Risk Factors and Lifestyles in the Development of Atrial Fibrillation Among Individuals Aged 20-39 Years.

Epidemiological evidence on the relationship of modifiable risk factors and lifestyles with incident atrial fibrillation (AF) in young adults remains insufficient. We aimed to identify the determinants of AF among young adults using a nationwide epidemiological database. Medical records of 286,876 individuals (20-39 years) without prior history of cardiovascular disease were extracted from the JMDC Claims Database. We analyzed the association of modifiable risk factors with the incidence of AF. The median (interquartile range) age was 34 (29-37) years, and 54.4% were men. After a mean follow-up of 1,017 ± 836 days, 267 individuals (0.1%) developed AF. Multivariable Cox regression analysis demonstrated that high waist circumference, hypertension, cigarette smoking, and poor sleep quality as well as age and sex were associated with increased incidence of AF. Kaplan-Meier curves showed that number of modifiable components including high waist circumference, hypertension, cigarette smoking, and poor sleep quality clearly stratified the risk of AF development (Log rank test, p < 0.001). Age- and sex-adjusted Cox regression analyses showed individuals with one (hazard ratio [HR] 1.56, 95% confidence interval [CI] 1.13-2.18), two (HR 2.03, 95% CI 1.40-2.95), three (HR 3.48, 95% CI 2.19-5.54), and four (HR 10.78, 95% CI 5.26-22.11) components were associated with an increased incidence of AF compared with individuals with no components. In conclusion, high waist circumference, hypertension, cigarette smoking, and poor sleep quality were associated with the development of AF among young adults, suggesting the importance of maintaining these modifiable factors for the primordial prevention of AF in young adults.