The association between COVID-19 vaccination and confirmed patients with hospitalization in Omicron era: A retrospective study

Abstract

With the emergence of Omicron variant of severe acute respiratory syndrome coronavirus 2, Taiwan has encountered the greatest coronavirus disease 2019 (COVID-19) pandemic since 2022 spring. We analyzed the characteristics, vaccinations, and outcomes of hospitalized COVID-19 patients quarantined in a dedicated ward. This retrospective study enrolled hospitalized COVID-19 patients in the dedicated wards of a district hospital in southern Taiwan from May 2022 to July 2022. We assessed in-hospital mortality, hospital length of stay (LOS), and dedicated ward LOS. Among 209 COVID-19 patients, the in-hospital mortality rates were 20.7% and 29.7% (P = .145) in patients with and without vaccination. A shorter dedicated ward LOS was noted in the vaccination group, with marginal statistical significance. Age, Charlson Comorbidity Index, and quick Sequential Organ Failure Assessment score were recognized as strong prognostic indicators for mortality in multivariable analysis. Vaccination demonstrated significant lower odds of death among relatively young populations in subgroup analysis. COVID-19 vaccination had significant efficacy in hospitalized COVID-19 patients in the relatively young group, and the effect may decline among individuals with advanced age and multiple comorbidities.