COVID-19 vaccine immunogenicity among chronic liver disease patients and liver transplant recipients: A meta-analysis

BACKGROUND/AIMS: Data of coronavirus disease 2019 (COVID-19) vaccine immunogenicity among chronic liver disease (CLD) and liver transplant (LT) patients are conflicting. We performed meta-analysis to examine vaccine immunogenicity regarding etiology, cirrhosis status, vaccine platform and type of antibody. METHODS: We collected data via three databases from inception to February 16, 2022, and reported pooled seroconversion rate, T cell response and safety data after two vaccine doses. RESULTS: Twenty-eight (CLD only: 5; LT only: 18; both: 2; LT with third dose: 3) observational studies of 3,945 patients were included. For CLD patients, seroconversion rate ranged between 84% (95% confidence interval [CI], 76–90%) and 91% (95% CI, 83–95%), based predominantly on neutralizing antibody and anti-spike antibody, respectively. Seroconversion rate was 81% (95% CI, 76–86%) in chronic hepatitis B, 96% (95% CI, 93–97%) in non-alcoholic fatty liver disease, 85% (95% CI, 75–91%) in cirrhosis and 85% (95% CI, 78–90%) in non-cirrhosis, 86% (95% CI, 78–92%) for inactivated vaccine and 89% (95% CI, 71–96%) for mRNA vaccine. The pooled seroconversion rate of anti-spike antibody was 66% (95% CI, 55–75%) after two doses of mRNA vaccines and 88% (95% CI, 58–98%) after third dose among LT recipients. T cell response rate was 65% (95% CI, 30–89%). Prevalence of adverse events was 27% (95% CI, 18–38%) and 63% (95% CI, 39–82%) among CLD and LT groups, respectively. CONCLUSIONS: CLD patients had good humoral response to COVID-19 vaccine, while LT recipients had lower response.