CXCL6 and atrial fibrillation: Through the IVW method, CD40l receptor levels (OR: 0.935, 95% CI: 0.901–0.970, p < 0.001) and CXCL6 (OR: 1.055, 95% CI: 1.001–1.113, p = 0.048) exhibited opposite effects on AF.