ABSTRACT
INTRODUCTION: The widespread impact of SARS-CoV-2 (COVID-19) has strained healthcare resources including available hospital beds and respiratory support. Patients who have been vaccinated against COVID-19 are less likely to become severely ill and require hospitalization. Current studies estimating the cost of hospitalization to the healthcare system are theoretical in nature and rely on statistical models. The risk of hospitalization, severe illness, and death remains much lower among vaccinated individuals. The primary objectives of this study were the effects of vaccination status on length of stay and cost of COVID-19 related hospitalization. Secondary objectives included rate of ICU admission and maximum level of respiratory support. METHOD(S): Setting: Single center study conducted at a large academic medical center Participants: 437 consecutively admitted patients with a diagnosis of COVID-19 infection met inclusion criteria in the study period. Of these, 79 were excluded for unknown or partial vaccination status, transfer from outside hospital, or multiple COVID-19 related admissions. Exposure: COVID-19 vaccination status Main Outcome and Measures: Hospital length of stay and cost of COVID-19 related hospitalization. RESULT(S): Overall, 279 (77.9%) unvaccinated patients compared to 79 (22.1%) vaccinated patients were hospitalized for the with a diagnosis of COVID-19. The length of stay was significantly lower in the vaccinated group (6.47 days versus 8.92 days, p = 0.03). The cost of hospitalization was not found to be statistically significant ($10,1885.0 versus $11,7936.3, p = 0.06). After conducting covariate analysis, adjusting for age, vaccinated patients had 21% lower cost compared to unvaccinated patients (p = 0.02). Vaccinated patients experienced a 70.6% lower risk of ICU admission (OR = 0.294, 95% CI 0.1219 to 0.7078, p = 0.006). Patients in the vaccinated group were also 46.2% less likely to be hospitalized beyond 7 days (OR = 0.537, 95% CI 0.306 - 0.941, p = 0.03). Unvaccinated patients required a higher degree of respiratory support (p= 0.002). CONCLUSION(S): Unvaccinated patients were found to have a longer length of stay compared to vaccinated patients when admitted for COVID-19. After adjusting for age, those who are vaccinated had a lower cost of hospitalization.