Role of Insulin Resistance in the Development of Nonalcoholic Fatty Liver Disease in People With Type 2 Diabetes: From Bench to Patient Care

Abstract

Insulin resistance is implicated in both the pathogenesis of nonalcoholic fatty liver disease (NAFLD) and its progression from steatosis to steatohepatitis, cirrhosis, and even hepatocellular carcinoma, which is known to be more common in people with type 2 diabetes. This article reviews the role of insulin resistance in the metabolic dysfunction observed in obesity, type 2 diabetes, atherogenic dyslipidemia, and hypertension and how it is a driver of the natural history of NAFLD by promoting glucotoxicity and lipotoxicity. The authors also review the genetic and environmental factors that stimulate steatohepatitis and fibrosis progression and their relationship with cardiovascular disease and summarize guidelines supporting the treatment of NAFLD with diabetes medications that reduce insulin resistance, such as pioglitazone or glucagon-like peptide 1 receptor agonists.

Figure 1

Disease progression in NAFLD. NAFLD encompasses a spectrum of liver disease, ranging from steatosis to steatohepatitis, with bouts of progression and regression from early to advanced fibrosis and cirrhosis. The more advanced the disease, the more limited the potential for regression is, until decompensated cirrhosis develops. At least 70% of people with type 2 diabetes are estimated to have NAFLD, and, among them, about half may have NASH. Fibrosis is believed to be present in 12–20% of all people with type 2 diabetes (,–13,65,68,89,90). RA, receptor agonist. T2DM, type 2 diabetes mellitus.