ObjectivesObesity, especially abdominal obesity, increases the prevalence of metabolic and cardiovascular disease (CVD). Fibroblast growth factor 21 (FGF21) has been identified as a critical regulator playing a therapeutic role in diabetes and its complications. This study aims to evaluate the relationship between serum FGF21 levels and body shape parameters in patients with hypertension (HP) and type 2 diabetes mellitus (T2DM).MethodsSerum FGF21 levels were determined in 1,003 subjects, including 745 patients with T2DM, and 258 individuals were selected as a healthy control in this cross-sectional study.ResultsSerum FGF21 levels were significantly higher in T2DM patients with HP than those without [534.9 (322.6–722.2) vs. 220.65 (142.8–347.55) pg/ml, p