Post-acute Sequelae of COVID-19 Case Fatality Rate and its Associated Covariates: A Systematic Review, Meta-Analysis and Meta-Regression

Background. Long COVID is a wide range of new, returning, or ongoing health problems experienced after primary COVID-19 infection, with a possibility of broad adverse outcomes. The aim of this study was to determine the case fatality of of post-acute sequelae of COVID-19 (PASC) and assess possible covariates. Population and Methods. We conducted a systematic review and meta-analysis from 43 studies (367,236 patients), (June, 2020 - August, 2022). PASC mortality was assessed from six studies. With random-effects model, the pooled case fatality was measured. Publication bias was ascertained and meta-regression analysis done on predetermined covariates. Results. The estimated prevalence of PASC was 42.5% (95% CI = 36.0 % - 49.3%).  The pooled case fatality was 7.4% (95% CI = 7.4% to 11.2%). The funnel plot suggested the presence of publication bias. Hospital re-admission (P = 0.0034) (R² = 1.00) and the year 2021 (P = 0.0309) (R² = 0.55) were associated with fatalities from PASC. Discussion. PASC increased the case-fatality of  COVID-19, particularly during the year 2021, reflecting a longer follow-up of patients and with hospital re-admission. It is recommended to monitor patients re-admitted to hospital post index COVID-19 closely monitor specific clinical parameters that may increase the risk of death.