Impact of Non-Alcoholic Fatty Liver Disease on COVID-19 Severity and Healthcare Outcomes: A Systematic Review

The systematic review investigated the association between non-alcoholic fatty liver disease (NAFLD) and COVID-19, focusing on pathophysiology, clinical outcomes, and public health implications. A comprehensive search of EBSCO, Scopus, and PubMed from January 2020 to December 2022 was conducted, following PRISMA guidelines. Included studies involved patients diagnosed with NAFLD or metabolic-associated fatty liver disease (MAFLD) and reported relevant comorbidities and COVID-19 outcomes. Quality was assessed using tools like the Newcastle-Ottawa Scale and AMSTAR-2. The review found that COVID-19 patients with NAFLD often had multiple comorbidities, especially diabetes and cardiovascular disease, which worsened outcomes. NAFLD was linked to higher hospitalization rates (odds ratio ~3.25), longer hospital stays by about two days, increased oxygen supplementation, higher ICU admissions, and a trend toward increased mortality, though mortality significance varied. Liver injury, indicated by elevated ALT and AST levels and hepatic steatosis on imaging, correlated with severe COVID-19. NAFLD patients showed systemic inflammation, immune dysregulation, and coagulation abnormalities contributing to disease severity. Ethnic disparities were noted, with certain groups having higher NAFLD prevalence and worse COVID-19 outcomes. These findings reveal challenges for healthcare systems due to increased resource demands and the need for integrated liver function monitoring during COVID-19 care. Overall, NAFLD significantly impacts COVID-19 severity through complex metabolic and immunological pathways, emphasizing the importance of clinical vigilance and multidisciplinary management for this high-risk population.