Association of Fibroblast Growth Factor 21 with Excessive Intrapancreatic Fat Deposition in Type 2 Diabetes Mellitus

OBJECTIVES: Fibroblast growth factor 21 is a metabolic regulator involved in glucose and lipid homeostasis. However, its relationship with excessive intrapancreatic fat deposition in type 2 diabetes mellitus remains unclear. We aimed to evaluate the association between serum fibroblast growth factor 21 levels and excessive intrapancreatic fat deposition in patients with type 2 diabetes mellitus.

METHODS: This prospective cross-sectional study included 101 participants who had previously undergone abdominal computed tomography. Group 1 consisted of patients with type 2 diabetes mellitus and excessive intrapancreatic fat deposition (n=31), Group 2 consisted of patients with type 2 diabetes mellitus without excessive intrapancreatic fat deposition (n=40), and Group 3 consisted of individuals without type 2 diabetes mellitus or excessive intrapancreatic fat deposition (n=30). Excessive intrapancreatic fat deposition was assessed on computed tomography by a blinded radiologist. Correlation, multivariable logistic regression, and receiver operating characteristic analyses were performed.

RESULTS: Fibroblast growth factor 21 levels were higher in Group 1 than in Groups 2 and 3 (82.32 pg/mL vs. 48.36 pg/mL vs 48.36 pg/mL, respectively; p<0.001). Serum fibroblast growth factor 21 levels were inversely correlated with the pancreas-to-spleen ratio in the overall cohort (ρ=- 0.527, p<0.001) and in the type 2 diabetes mellitus subgroup (ρ=- 0.510, p<0.001). In multivariate analysis, higher serum fibroblast growth factor 21 levels were independently associated with excessive intrapancreatic fat deposition both in the subgroup with diabetes (odds ratio: 1.03, 95% confidence interval: 1.01-1.05; p=0.004) and in the overall study population (odds ratio: 1.03, 95% confidence interval: 1.01-1.05; p=0.003). Receiver operating characteristic analysis showed an area under the curve (AUC) of 0.796 for fibroblast growth factor 21 in predicting excessive intrapancreatic fat deposition. A fibroblast growth factor 21 cutoff value of>62.15 pg/mL yielded a sensitivity of 83.87% and a specificity of 67.14%.

CONCLUSIONS: Serum fibroblast growth factor 21 levels were increased in patients with type 2 diabetes mellitus and excessive intrapancreatic fat deposition and were independently associated with excessive intrapancreatic fat deposition. Circulating fibroblast growth factor 21 may reflect pancreatic fat accumulation in the setting of metabolic dysfunction.