A Concise Review on Hepatitis C Virus Infection-Associated Type 2 Diabetes Mellitus and Its Impact on Anti-HCV Therapy

Hepatitis C virus (HCV), an RNA-containing virus, has infected more than 170 million people worldwide and is one of the leading causes of deaths in developing countries due to its propensity to progress to chronic states, followed by multiple fibrosis and scar formation (cirrhosis) and even hepatocellular carcinoma. Type 2 diabetes mellitus (T2DM), a metabolic disorder, is one of the diseases of civilization, and its prevalence has shown an increasing tendency globally. At present, more than 350 million people worldwide are suffering from T2DM. T2DM is considered the most common extrahepatic linkage of HCV infection, which is associated with prevalent morbidity and mortality patterns. Several studies have reported that HCV patients are more prone to developing T2DM as compared to healthy non-infected individuals. Extensive studies have revealed that HCV patients tend to develop insulin resistance (IR), which plays a crucial role in the development of T2DM. IR develops through several pathophysiological mechanisms, including the inhibition of insulin signaling pathway that induces central IR by HCV proteins and increased lipolysis as well as the overproduction of inflammatory cytokines, which promote peripheral IR. IR has a direct effect on the association of HCV with T2DM, and it has been found associated with impaired sustained virological response (SVR) and a higher incidence of hepatocellular carcinoma in HCV patients. Therefore, it has been suggested that chronic HCV patients must be treated with anti-HCV therapy along with antidiabetic medications to better achieve SVR. In this review, we briefly describe HCV infection, its diagnosis, global epidemiology, treatment options, and its association with DM, along with its impact on anti-HCV therapy.