Lifestyle Factors and Thromboembolic Risk in Atrial Fibrillation: Age-Dependent Effects of Smoking and Alcohol Consumption

BACKGROUND: Atrial fibrillation (AF) relates to cardioembolic stroke (CS), but the role of lifestyle factors, including smoking and alcohol, remains unclear. METHODS: This retrospective, nationwide, multicenter case-control study used the Inpatient Clinico-Occupational Database of the Rosai Hospital Group from 2005 to 2022. Patients with AF and CS were identified using ICD-10 codes. Smoking status and alcohol consumption were assessed at admission through structured interviews. We examined age-stratified differences in smoking and alcohol consumption and evaluated the impact of smoking and alcohol intake on the risk of CS. RESULTS: Among 26 915 patients, 5688 had AF-related CS and 21 227 had AF without CS. Current smoking was more prevalent in AF patients with CS aged from 40-49 to 80-89 years than those without (all p < 0.001). Multivariable logistic regression showed smoking was independently associated with CS overall (all p < 0.001) and by age group, and daily alcohol intake was associated with CS overall and in patients ≤ 75 years (p = 0.021 and 0.044). The combined score of chronic heart failure, hypertension, age > 75-year (weighted × 2), and diabetes mellitus (CHA₂D, range 0-5) increased with age, from 0.66, 0.67, 1.36, 2.43, 2.83, and 2.94 (average) in the 40-49, 50-59, 60-69, 70-79, 80-89, and ≥ 90-year groups (p < 0.001), whereas the prevalence of current smoking and daily alcohol consumption declined progressively with age (p < 0.001). CONCLUSIONS: Smoking and daily alcohol consumption associate with CS risk in AF patients, especially younger individuals with low CHA₂D scores, highlighting the role of lifestyle in risk assessment.