Impact of Liver Test Abnormalities and Chronic Liver Disease on the Clinical Outcomes of Patients Hospitalized with COVID-19

Background and Aims: The impact of SARS-CoV-2 infection on the liver and the possibility of chronic liver disease (CLD) as a risk factor for COVID-19 severity is not fully understood. Our goal was to describe clinical outcomes of COVID-19 inpatients regarding the presence of abnormal liver tests and CLD. Methods: A retrospective analysis of patients with SARS-CoV-2 infection, hospitalized in a tertiary center in Portugal, was performed. Studied outcomes were disease and hospitalization length, COVID-19 severity, admission to intensive care unit (ICU) and mortality, analyzed by the presence of abnormal liver tests and CLD. Results: We included 317 inpatients with a mean age of 70.4 years, 50.5% males. COVID-19 severity was moderate to severe in 57.4% and critical in 12.9%. The mean disease length was 37.8 days, the median hospitalization duration 10.0 days and overall mortality 22.8%. At admission, 50.3% showed abnormal liver tests, and 41.5% showed elevated aminotransferase levels, from which 75.4% were mild. Elevated aminotransferase levels at admission were associated with COVID-19 severity (78.7 vs. 63.3%, p = 0.01), ICU admission (13.1 vs. 5.92%, p = 0.034) and increased mortality (25.8 vs. 13.3%, p = 0.007). However, in a subgroup analysis, only aspartate transaminase (AST) was associated with these worse outcomes. Alkaline phosphatase was elevated in 11.4% of the patients and was associated with critical COVID-19 (21.1 vs. 9.92%, p = 0.044) and mortality (20.4 vs. 9.52%, p = 0.025), while 24.6% of the patients showed elevated gamma-glutamyl transferase, which was associated with ICU admission (42.3 vs. 22.8%, p = 0.028). Fourteen patients had baseline CLD (4.42%), 3 with liver cirrhosis. Alcohol (n = 6) and nonalcoholic fatty liver disease (n = 6) were the most frequent etiologies. CLD patients had critical COVID-19 in 21.4% (p = 0.237), mean disease length of 36.6 days (p = 0.291), median hospitalization duration of 11.5 days (p = 0.447) and a mortality rate of 28.6% (p = 0.595), which increased to 66.7% among cirrhotic patients (p = 0.176). Conclusions: Liver test abnormalities in COVID-19 patients were frequent but most commonly mild. AST, but not alanine transaminase, was associated with worse clinical outcomes, such as COVID-19 severity and mortality, probably indicating these outcomes were independent of liver injury. A low prevalence of CLD was seen, and a clear impact on COVID-19 outcomes was not seen.