APLN and type 1 diabetes mellitus: Results: Apelin levels were lower in patients with prolonged T1Dcompared with patients with recent‐onset T1D and controls, (117.9 ± 94.3,228.3 ± 181.6, and 224.4 ± 138.4 pg/ml, respectively; analysis of variance (ANOVA)p = 0.029).