Association of non-alcoholic fatty liver disease with COVID-19 severity and pulmonary thrombosis: CovidFAT, a prospective, observational cohort study

ABSTRACT

Background Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease associated with systemic changes in immune response which might be associated with COVID-19 severity. The aim of this study was to investigate the impact of NAFLD on COVID-19 severity and outcomes. Methods A prospective observational study included consecutively hospitalized adult patients with severe COVID-19 between March and June 2021. Patients were screened for fatty liver by ultrasound and subsequently diagnosed with NAFLD. Patients were daily followed until discharge, and demographic, clinical and laboratory data were collected and correlated to clinical outcomes. Results Of the 216 patients included, 120 (55.5%) had NAFLD. NAFLD group had higher C-reactive protein (84.7 mg/L, IQR 38.6-129.8 vs 66.9, 32.2-97.3, p=0.0340), Interleukin-6 (49.19 ng/L, IQR 22.66-92.04 vs 13.22, IQR 5.29-39.75, p<0.0001), aspartate aminotransferase (58 IU/L, IQR 40-81 vs 46, IQR 29-82, p=0.0123), alanine aminotransferase (51 IU/L, IQR 32-73 vs 40, IQR 23-69, p=0.0345) and lactate dehydrogenase (391 IU/L, IQR 285-483 vs 324, IQR 247-411, p= 0.0027). The patients with NAFLD had higher disease severity assessed by seven-category ordinal scale, more frequently required HFNC or NIV (26, 21.66% vs 10, 10.42%, p=0.0289), had longer duration of hospitalization (10, IQR 8-15 vs. 9, IQR 6-12 days, p=0.0018) and pulmonary thromboembolism (26.66% vs. 13.54%, p=0.0191). On multivariable analyses, NAFLD was negatively associated with time to recovery (HR 0.64, 95%CI 0.48-0.86) and was identified as a risk factor for pulmonary thrombosis (OR 2.15, 95%CI 1.04-4.46). Conclusions NAFLD is associated with higher COVID-19 severity, adverse outcomes and pulmonary thrombosis.