Comparative admission rates and infection severity of COVID-19 among unvaccinated and vaccinated patients

Vaccination efforts have limited the burden of the pandemic caused by the coronavirus disease 2019 (COVID-19) with substantial evidence showing reduced hospitalization rates among vaccinated populations. However, few studies have explored correlations between vaccination status and inpatient COVID-19 outcomes. This observational case–control study involved a retrospective chart review of adult patients hospitalized for COVID-19 infection at a medium-sized hospital in Central Michigan between May 1, 2021 and September 30, 2021. Unadjusted analyses involved t-tests and chi-square tests followed by adjusted analyses using binary logistic and linear regression models. Of the 192 screened patients, 171 subjects met the inclusion criteria. Vaccinated patients were significantly older (71.09 vs 57.45, p