FGF23 and atrial fibrillation: Three biomarkers were also selected: elevated BNP and fibroblast growth factor-23 (FGF-23) were robustly associated with AF (OR = 1.293 per fold change increase; 95% CI = 1.11–1.63; P = 0.002 and OR = 1.667, 95% CI = 1.36–2.34; P = 0.001, respectively).