Liver disease and diabetes: association, pathophysiology, and management

Diabetes is associated with a spectrum of liver diseases including nonalcoholic liver disease, steatohepatitis, and liver cirrhosis with their increased complications and mortality. Hepatitis C virus (HCV) and its associated liver cirrhosis has been associated with diabetes through insulin resistance. Cryptogenic diabetes occurs as a consequence of liver cirrhosis with the pathophysiology being complex, but mostly attributed to the increased insulin resistance in muscle, liver, and adipose tissue. As for the management of diabetes in patients with liver disease, lifestyle modification plays an important role. Oral diabetic medications are contraindicated in patients with advanced liver diseases with associated cirrhosis, ascites, or encephalopathy. As for stable liver disease, metformin and thiazolenediones have shown mixed results, with some showing them to be effective in improving liver transaminases in addition to histological improvement in steatosis and inflammation. α-glucosidase inhibitors may be helpful in decreasing hepatic encephalopathy. Upregulation of Dipeptidyl peptidase-4 (DPP-4) has been suggested as a possible pathogenetic mechanism for HCV-related insulin resistance, and treatment with DPP-4 inhibitors could improve insulin sensitivity in diabetic patients with liver disease. Patients with impaired liver function with associated insulin resistance may need increased insulin requirements. On the other hand patients with altered liver metabolism might need decreased insulin requirements.