Metabolic Steatotic Liver Disease - Chapter 16: Fatty liver and viral hepatitis: Prevalence, risk factors, natural course, pathogenesis, and management

Fatty liver disease (FLD) associated with metabolic abnormalities is the fastest growing etiology among chronic liver diseases, while chronic hepatitis B (CHB) and C (CHC) remain the main etiologies of liver cirrhosis and hepatocellular carcinoma. In this chapter, the epidemiology and outcomes associated with FLD combined with CHB or CHC were reviewed. The noted prevalence of combined FLD and CHB or CHC was between 30% and 70%. The major risk factors were metabolic syndrome, obesity, diabetes, and dyslipidemia for FLD increased the risk of disease progression for both CHC and untreated CHB. However, FLD enhanced a better CHB viral control. For treated CHB patients, FLD decreased not only the risk of HCC but also increased the response to nucleot(s)ide analogs. Unlike CHB, FLD did not impact the efficacy of current hepatitis C direct-acting antiviral therapy. Patients with chronic viral hepatitis should be screened for FLD in order to provide appropriate interventions to consider a more aggressive control of FLD given the poor outcomes if combining FLD.