In dose-response analysis, a linear positive association was noted between serum FGF-23 levels and the risk of AF (P <sub>nonlinear</sub> = 0.9507), with a RR elevation of 7% for every 20 pg/ml increase in the serum FGF-23 levels (95% CI: 1.02-1.13). Here, FGF23 is linked to atrial fibrillation.