After adjusting for potential confounding variables (age, sex, race/ethnicity, height, body mass index, systolic blood pressure, antihypertension therapy, diabetes status, current smoker, current alcohol use, and total and HDL cholesterol), and accounting for multiple testing (P < 0.05/15 = 0.0033), circulating levels of the following proteins were positively associated with a higher risk of AF: MMP-2 (HR per standard deviation increment, 1.27; 95% CI 1.11‒1.45), TIMP-2 (HR 1.28; 95% CI 1.12‒1.46), VCAM-1 (HR 1.32; 95% CI 1.16‒1.50), and SLPI (HR 1.22; 95% CI 1.07‒1.38). This evidence concerns the gene SLPI and atrial fibrillation.