A subgroup analysis was performed based on the type of AF on 5 studies and it showed a positive correlation between high TGF-β1 plasma levels and the risk of new-onset AF (SMD 1.07; 95%CI 0.26–1.89) with significant heterogeneity (I2 = 95%, P<0.00001) across studies. This evidence concerns the gene TGFB1 and atrial fibrillation.