The effectiveness of COVID-19 vaccination against all-cause mortality in patients with type 2 diabetes mellitus: The observation during the initial period of the cancellation of the "Dynamic Zero Policy" in mainland China

Abstract

Aims: This study aims to assess the effectiveness of COVID-19 vaccination against all-cause death in patients with type 2 diabetes mellitus (T2DM).

Methods: Subjects were patients with T2DM who were administered by general practitioner (GP). Use electronic exchange platform to obtain the information on COVID-19 vaccination, all-cause deaths and risk factors. Logistic regression models were used to calculate the odd ratio (OR) and 95% CI for the association between COVID-19 vaccination and mortality. The vaccine effectiveness (VE) was calculated as (1- adjusted OR) × 100%.

Results: A total of 26,916 subjects had 53.81%, 17.65%, and 23.43% coverage for the booster, full, and partial COVID-19 vaccination, reported 328 deaths and a mortality of 1.2%. The adjusted OR (95%CI) was 0.85(0.60-1.21) for those received partial vaccination, 0.31(0.22-0.43) for those received full vaccination, and 0.12(0.08-0.18) for those received booster vaccination, compared to the unvaccinated individuals. The VE (95%CI) was 88.00%(82.30-91.80) of booster vaccination, 69.30%(56.60-78.30) of full vaccination, and 17.60%(-17.10-42.00) of partial vaccination.

Conclusion: COVID-19 vaccination could effectively prevent the all-cause death in patients with T2DM during the omicron variant outbreak period, after the cancellation of the "Dynamic Zero Policy" in mainland China.

Keywords: All-cause death; COVID-19 vaccination; SARS-CoV-2; Type 2 diabetes mellitus; Vaccine effectiveness.