Impact of Fibrosis-4 Index Prior to COVID-19 on Outcomes in Patients at Risk of Non-alcoholic Fatty Liver Disease

Background: Severity of disease and outcomes in patient with COVID-19 has been associated with several risk factors tied to the metabolic syndrome. Aims: We conducted a study with the objective of describing the association between the baseline Fibrosis-4 (FIB-4) index prior to SARS-CoV-2 infection and the severity of COVID-19 among patients at risk of non-alcoholic fatty liver disease (NAFLD). Methods: This was a retrospective cohort study of patients with at least two risk factors for metabolic syndrome diagnosed with COVID-19. The main exposure of interest was FIB-4 index prior to infection, categorized into three previously validated age-specific levels. The main outcomes of interest were disease requiring hospitalization and in-hospital mortality. Results: We included 373 patients [median age, 62 years; 194 male (52%); median number of metabolic syndrome risk factors, 3]. The median FIB-4 index was 1.10 (interquartile range 0.78–1.61). In models adjusting for diabetes mellitus and chronic kidney disease, patients with intermediate FIB-4 index had 67% higher odds of hospitalization compared to those in the low category {odds ratio (OR) 1.67 [(95% CI 1.06–2.64); p = 0.03]} and patients with high FIB-4 index had higher odds of mortality compared to intermediate and low category with an OR 2.22 (95% CI 1.20–4.12; p = 0.01). However, when we evaluated components of FIB-4 (age and AST/ALT ratio), we found that age alone was the best predictor of hospitalization and mortality. Conclusions: Among patients at risk of NAFLD with COVID-19 infection, elevated pre-infection FIB-4 index was associated with worsened clinical outcomes, but age was the strongest predictor.