Dipeptidyl Peptidase IV Inhibitor Improves Insulin Resistance and Steatosis in a Refractory Nonalcoholic Fatty Liver Disease Patient: A Case Report

A 67-year-old Asian woman was referred to Kurume University Hospital due to abnormal liver function tests. She was diagnosed with nonalcoholic fatty liver disease (NAFLD). NAFLD was treated by diet therapy with medication of metformin and pioglitazone; however, NAFLD did not improve. Subsequently, the patient was administered sitagliptin. Although her energy intake and physical activity did not change, her hemoglobin A1c level was decreased from 7.8 to 6.4% 3 months after treatment. Moreover, her serum insulin level and homeostasis model assessment-insulin resistance value were also improved, as was the severity of hepatic steatosis. These findings indicate that sitagliptin may improve insulin resistance and steatosis in patients with refractory NAFLD.