The objective of this study was to measure plasma fibroblast growth factor 21 and 19 (FGF21 and FGF19) levels in patients with Cushing's syndrome (CS) and to compare it with those of lean control subjects (C) and patients with obesity (OB). Fourteen untreated patients with CS, 19 patients with OB and 36 controls were included in the study.
Plasma FGF19 did not significantly differ among the studied groups. Plasma FGF21 levels were significantly higher in both CS and OB groups relative to C group but they did not differ between CS and OB groups.
In a combined population of all three groups FGF21 levels positively correlated with BMI, waist circumference and percentage of total and truncal fat mass. Less prominent inverse relationship with these parameters was found for FGF19.
Neither FGF21 nor FGF19 were significantly related to cortisol concentrations.