APOA1 and atrial fibrillation: Compared with controls, APOA1 levels in AF patients were significantly lower in men(1.07 ± 0.25 vs. 1.15 ± 0.24 g/L, P < 0.001; Fig. 2(A)) and women (1.19 ± 0.27 vs. 1.30 ± 0.23 g/L, P < 0.001; Fig. 2(A)), significantly lower in patients with age ≤ 60 years (1.14 ± 0.26 vs. 1.17 ± 0.22 g/L, P < 0.001; Fig. 2(B)) and age > 60 years (1.13 ± 0.27 vs. 1.24 ± 0.25 g/L, P < 0.001; Fig. 2(B)).