Impact of COVID-19 Vaccination on Fatality and Intensive Care Unit Admission in Patients with Type 2 Diabetes Mellitus

Abstract

Objective: This study aims to investigate the influence of coronavirus (COVID-19) vaccination on hospital outcomes among patients with type 2 diabetes mellitus (T2DM). Methods: A total of 324 patients hospitalized for COVID-19 were evaluated retrospectively. Type 2 diabetes mellitus patients were matched 1:1 by the propensity score matching method to individuals without diabetes for age and gender. After matching, we analyzed 70 patients with T2DM and 70 without diabetes. Results: Individuals with T2DM exhibited a slightly higher vaccination rate than those without diabetes (67.1% vs. 54.3%, P=.119). Regardless of diabetes status, vaccinated participants experienced significantly lower rates of intensive care unit (ICU) admission (T2DM: 14.9% vs. 60.9%, P=.001; nondiabetics: 5.3% vs. 37.5%, P = .001) and fatality (T2DM: 2.1% vs. 60.9%, P=.001; non-diabetics: 0% vs. 46.9%, P=.001) compared to the unvaccinated group. The length of hospitalization and ICU admission rate were insignificantly higher in vaccinated individuals with T2DM than those without diabetes (9.0 days vs. 7.0 days, P=.154; 14.9% vs. 5.3%, P=.179). Multivariate logistic regression in T2DM patients revealed that CoronaVac vaccination significantly reduced ICU admission (OR: 0.089, 95% CI 0.022-0.360, P=.001), while male gender increased the risk (OR: 6.59, 95% CI 1.545-28.11, P=.011). Conclusion: In vaccinated individuals with T2DM, the risk of severe COVID-19 and fatality significantly decreased, similar to individuals without diabetes. This protection is not affected by vaccine type, vaccination count, or age.