Risk of Death in Patients Hospitalized for COVID-19 vs Seasonal Influenza in Fall-Winter 2022-2023
The study “Risk of Death in Patients Hospitalized for COVID-19 vs Seasonal Influenza in Fall-Winter 2022-2023” compares the mortality risk between COVID-19 and seasonal influenza hospitalizations.
This detailed summary:
- Study Objective: The study aimed to assess whether COVID-19 still correlates with a higher risk of death compared to seasonal influenza, especially given changes in the virus, clinical care, and population-level immunity since the early pandemic.
- Methods: Utilizing US Department of Veterans Affairs health databases, the study enrolled individuals hospitalized with either COVID-19 or influenza between October 1, 2022, and January 31, 2023. It employed inverse probability-weighted Cox survival models and propensity score weighting to evaluate the risk of death and balance the two groups.
- Results: The study included 8,996 hospitalizations for COVID-19 (538 deaths, 5.98%) and 2,403 for seasonal influenza (76 deaths, 3.16%). It found a 30-day death rate of 5.97% for COVID-19 compared to 3.75% for influenza, indicating a 2.23% excess death rate for COVID-19. Hospitalization for COVID-19 was associated with a higher risk of death (hazard ratio 1.61) compared to influenza. Additionally, the risk of death decreased with the number of COVID-19 vaccinations.
- Discussion: The study observed that the risk of death from COVID-19 remains higher compared to seasonal influenza, but the gap has narrowed since the early pandemic. The decrease in COVID-19 mortality rates might be attributed to changes in virus variants, increased immunity from vaccination and prior infection, and improved clinical care. The study also noted the significantly higher risk of death among unvaccinated individuals compared to those vaccinated or boosted. However, the study’s generalizability may be limited due to its focus on an older, predominantly male VA population. Also, the study did not investigate causes of death or account for non-hospitalized individuals.
In summary, this study provides updated insights into the relative risks of death from COVID-19 and seasonal influenza hospitalizations during the fall-winter of 2022-2023. It highlights the continuing higher risk associated with COVID-19, albeit reduced from early pandemic levels, and underscores the importance of vaccination in reducing COVID-19 mortality.