BACKGROUND: Dipeptidyl peptidase-4 (DPP-4) inhibitors might have pleiotropic effects because receptors for incretin exist in various tissues, including liver. We examined whether DPP-4 inhibitors affect liver function in patients with type 2 diabetes.

MATERIAL AND METHODS: A retrospective review of 459 patients with type 2 diabetes who were prescribed DPP-4 inhibitors was performed. After exclusion of patients with hepatitis B or C, steroid use, and other diseases that might affect liver function and diabetes status, 224 patients were included in the analysis.

RESULTS: Forty-four patients (19.6%) with liver injury defined by aspartate transaminase (AST) or alanine transaminase (ALT) over the normal level of 40 U/L. In the patients with liver injury, AST and ALT were significantly decreased after 6 months from the first date of DPP-4 prescription, with mean changes of –6.2 U/L [95% confidence interval (CI) –10.9 to –1.4, p=0.012] and of –11.9 U/L (95%CI –19.5 to –4.2, p=0.003), respectively. Percent changes in AST were significantly and negatively correlated with baseline AST and ALT (r=–0.27, p<0.001 and r=–0.23, p=0.002, respectively), and percent changes in ALT were also negatively correlated with them (r=–0.23, p=0.001 and r=–0.27, p<0.001, respectively).

CONCLUSIONS: DPP-4 inhibitors improved liver dysfunction in patients with type 2 diabetes.

Keywords: Alanine Transaminase - blood, Aspartate Aminotransferases - blood, Body Weight, Diabetes Mellitus, Type 2 - drug therapy, Dipeptidyl-Peptidase IV Inhibitors - therapeutic use, Hemoglobin A, Glycosylated - metabolism, Liver Diseases - drug therapy