Background: COVID-19 vaccines have reduced the risk of disease progression to respiratory failure or death. However, in patients with breakthrough infections requiring invasive mechanical ventilation, the effect of prior COVID-19 vaccination on mortality remains inconclusive.
Method: We retrospectively analyzed data on patients intubated due to COVID-19 pneumonia between May 1, 2022 and October 31, 2022. Receipt of two or more doses of vaccine were considered as fully vaccinated. The primary outcome was the time from intubation to all-cause intensive care unit (ICU) mortality.
Result: A total of 84 patients were included (40 fully vaccinated versus 44 controls). The baseline characteristics, including age, comorbidities, and Sequential Organ Failure Assessment (SOFA) score on the day of intubation were similar between the two groups. The difference in ICU mortality rate between the fully vaccinated and control groups was not significant (35 % vs. 25 %, P = 0.317; hazard ratio with 95 % confidence interval = 1.246 (0.575-2.666), P = 0.571). The SOFA score (hazard ratio: 1.319, P = 0.001) and body mass index (BMI) (hazard ratio: 0.883, P = 0.022) were significantly associated with ICU mortality.
Conclusion: Being fully vaccinated was not associated with a mortality benefit in intubated patients with COVID-19. A higher SOFA score on the day of intubation and lower BMI were poor prognostic factors.
Keywords: COVID-19; Critical care; Mechanical ventilation; Mortality; Vaccination.
Copyright © 2023 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.