Vaccination status among patients with the need for emergency hospitalizations related to COVID-19.

Background: It is thought vaccines allowed for emergency use significantly reduce hospitalizations and emergency room visits. It is a matter of curiosity how many of the patients who come to the emergency department (ED) are vaccinated. We aimed to examine the characteristics of ED patients needing hospitalizations related to moderate and severe COVID-19 by vaccination status.

Methods: A retrospective study of 559 rRT-PCR-confirmed SARS-CoV-2 infection cases with moderate or severe COVID-19 needing hospitalization was performed in August 2021. Univariate and multivariate logistic regression analyses were performed for factors associated with mortality.

Results: The mean age of the patients was 60.8 ± 18.1 years old, and 54.2% (n = 303) of the patients were women. The most common comorbidities were hypertension (37.2%), diabetes mellitus (31.1%) and chronic obstructive pulmonary disease (13.8%), respectively. The number of patients with alpha variant was 399 (71.4%), and delta variant was 83 (14.8%). Fifty point 6% (n = 283) of the patients were fully vaccinated. The total number of patients who died in the study was 114 (20.4%), and the number of patients hospitalized in the intensive care unit was 168 (30.1%). The day between the last dose of vaccine and hospitalization was 117 ± 45.9 days. In multivariate logistic regression analysis: age (odds ratio (OR), 1.05; 95% confidence intervals (95% CI) 1.03-1.08- year increase), male gender (OR, 1.8; 95% CI, 1.1-2.9), presence of at least one comorbid disease (OR, 2; 95% CI, 1.1-3.7) and partial (OR, 0.24;95% CI, 0.09-0.6) and fully vaccinated status (OR, 0.1; 95% CI, 0.05-0.18) were associated with mortality among COVID-19 patients.

Conclusions: In this study, age older than 65, unvaccinated, and comorbidities had significantly higher mortality. In multivariate regression analyses, age, vaccination status, comorbidities and the male gender were associated with mortality. Our study did not evaluate the vaccine efficacy but, a lower mortality rate was observed in those fully vaccinated with CoronaVac and Pfizer-BioNTech. Additionally, Alpha, Delta and other variants had the same mortality rates.