Abstract
The coronavirus disease 2019 (COVID-19) outbreak is a major threat to human beings. Lung injury has been reported as the major outcome of COVID-19 infection. However, liver damage has also been considered to occur in severe cases. The current meta-analysis of retrospective studies was carried out to summarize available findings on the association between liver injury and severity of COVID-19 infection. Online databases including PubMed, Scopus, Web of Science, and Cochrane Library were searched to detect relevant publications up to 1 April 2020, using relevant keywords. To pool data, a fixed- or random-effects model was used depending on the heterogeneity between studies. Furthermore, publication bias test and sensitivity analysis were also applied. In total, 20 retrospective studies with 3428 COVID-19 infected patients (severe cases, n = 1455; mild cases, n = 1973), were included in this meta-analysis. Higher serum levels of aspartate aminotransferase (weighted mean difference, 8.84 U/L; 95% confidence interval [CI] 5.97 to 11.71; P < 0.001), alanine aminotransferase (weighted mean difference, 7.35 U/L; 95% CI, 4.77 to 9.93; P < 0.001), total bilirubin (weighted mean difference, 2.30 mmol/L; 95% CI, 1.24 to 3.36; P < 0.001), and lower serum levels of albumin (weighted mean difference, -4.24 g/L; 95% CI, -6.20 to -2.28; P < 0.001) were associated with a significant increase in the severity of COVID-19 infection. The incidence of liver injury, as assessed by serum analysis (aspartate aminotransferase, alanine aminotransferase, total bilirubin, and albumin levels), seems to be higher in patients with severe COVID-19 infection.