Impact of Unhealthy Lifestyles on Patients With Atrial Fibrillation at Low Risk of Stroke: A Nationwide Cohort Study

Background: The impact of unhealthy lifestyles on clinical outcomes among patients with atrial fibrillation (AF) who are at low risk of stroke remains uncertain. The study objective was to evaluate the association between unhealthy lifestyles and clinical outcomes among low-risk AF patients with 0-1 non-sex risk factor of the CHA ₂DS ₂-VASc (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, prior Stroke or transient ischemic attack [TIA], Vascular disease, Age 65-74 years, female Sex;) score. Methods: A total of 52,451 low-risk AF patients (mean age 51.6 ± 10.4 years) were evaluated with the National Health Insurance Service of the Republic of Korea database between 2009 and 2016. Using the survey on health habits, an unhealthy lifestyle score (ULS) was calculated by adding one point each if a respondent had a sedentary lifestyle, drinking, or smoking. The primary outcome was the composite of myocardial infarction, ischemic stroke, heart failure, and all-cause death. Multivariable Cox regression analysis was used to estimate the risk of the study outcome according to the ULS. Results: There was a total of 12,792 (24.4%), 24,785 (47.3%), 11,602 (22.1%), and 3272 (6.2%) low-risk AF patients with 0 to 3 points of the ULS, respectively. The median follow-up period was 4.1 (2.1-6.1) years. Compared with the healthiest-lifestyle group (ULS 0), the other groups were associated with significantly higher risks of the primary outcome, with a gradually increasing trend according to the ULS (adjusted hazard ratio [95% confidence interval] =1.17 [1.05-1.31], 1.37 [1.21-1.56], 1.82 [1.53-2.17], for the groups with ULS 1, 2, and 3, respectively). Conclusion: Unhealthy lifestyles, including a sedentary lifestyle, drinking, and smoking, may synergistically impact poor clinical outcomes in AF patients who are deemed to be at low risk of stroke.