Acromegaly is associated with high fibroblast growth factor-21 levels.

Fibroblast growth factor-21 (FGF-21) is a member of fibroblast growth factor family. Both growth hormone (GH) and FGF-21 take place in the regulation of glucose and lipid metabolism. We aimed to investigate FGF-21 levels in acromegaly which is characterized by excess GH levels and is associated with comorbidities and altered body composition. We studied 43 subjects (21 females and 22 males, mean age of 50.0 ± 12.8) with acromegaly. The control group consisted of 40 gender- and age-matched subjects (25 females and 15 males, mean age of 48.8 ± 8.8). Acromegaly patients were classified into two groups; active acromegaly (AA; n = 26) and controlled acromegaly (CA; n = 17). Metabolic, anthropometric and laboratory values of subjects were recorded. FGF-21 level was measured by ELISA assay. Median FGF-21 levels were significantly higher in acromegaly group compared to control group (85.5 vs. 59.0 pg/mL, p = 0.02, respectively). In the multiple regression model, FPG, A1c, HOMA-IR, glucose intolerance, BMI, visceral fat, hs-CRP, presence of hypertension, dyslipidemia and acromegaly were included as independent variables to explain variability of plasma FGF-21 levels in whole study group. The presence of acromegaly was the only determinant of increased FGF-21 levels in the whole study group (β coefficient = 0.253, p = 0.006). FGF-21 levels were increased significantly in acromegaly group. Increased FGF-21 levels were significantly and independently associated with the state of acromegaly. Acromegaly may also be a FGF-21 resistance state independent from insulin resistance, glucose intolerance, obesity, hypertension and dyslipidemia.