Cigarette Smoking and Structural Brain Deficits in Patients With Atrial Fibrillation

Cigarette smoking and atrial fibrillation (AF) are associated with impaired brain health. We investigated the association between smoking habits and brain lesions and volume in patients with AF. In patients with AF from a multicenter cohort study, we assessed smoking status (never, ex-, active), number of cigarettes smoked per day, smoking duration (years), pack-years, and time since smoking cessation. On brain magnetic resonance imaging, the prevalence and volumes of white matter lesions (WML) and small noncortical infarcts, and the volumes of gray matter and white matter were evaluated. Logistic and linear regression analyses were used to analyze the association between smoking habits and brain lesions and volumes. A total of 1,728 patients were enrolled (mean age 72.6 years, 27.5% female); 7.5% were active smokers; 48.5% were ex-smokers, and 44% had never smoked. We found linear associations of number of cigarettes smoked per day, pack-years, and older age at smoking cessation with reduced gray matter volume (p for linear trend <0.01, 0.02, and 0.01, respectively). Patients with a smoking duration in the second and third tertile had a greater risk for WML Fazekas ≥2 (odds ratio 1.86, 95% confidence interval 1.29 to 2.69, p <0.01 and 1.47 [1.02 to 2.12], p = 0.04), and exhibited larger WML volumes. Patients who had stopped smoking ≥16 years before enrollment were less likely to have small noncortical infarcts (odds ratio 0.46, 0.25 to 0.88, p = 0.02) and had smaller WML volumes (β: -0.451 mm³, -0.8 to -0.11, p = 0.01). In conclusion, smoking intensity and time since smoking cessation were associated with the presence and volume of brain lesions and with brain volumes in patients with AF.