OR34-01 Incidence Of Diabetes Following COVID-19 Vaccination And SARS-CoV-2 Infection: A Population-Based Cohort Study
Authors: Lui David , Xi Xiong , Chung Matthew , Au Ivan , Lai Francisco , Wan Eric , Chui Celine , Li Xue , Cheng Franco , Cheung Ching Lung , Chan Esther , Lee Chi Ho , Woo Yu Cho , Tan Kathryn C B , Wong Carlos , Wong Ian 
Published: October 2023

Abstract
Disclosure: D. Lui: None. X. Xi: None. M. Chung: None. I. Au: None. F. Lai: None. E. Wan: None. C. Chui: None. X. Li: None. F. Cheng: None. C. Cheung: None. E. Chan: None. C. Lee: None. Y. Woo: None. K.C. Tan: None. C. Wong: None. I. Wong: None.
Objectives: The risk of incident diabetes following COVID-19 vaccination remains to be evaluated. Also, it is unclear whether the risk of incident diabetes after SARS-CoV-2 infection is modified by vaccination status or differs by SARS-CoV-2 variants. We evaluated the incidence of diabetes following mRNA (BNT162b2), inactivated (CoronaVac) COVID-19 vaccines, and after SARS-CoV-2 infection. Methods: Two separate COVID-19 vaccination and infection cohorts were extracted from a population-based electronic health database in Hong Kong. The vaccination cohort included people who received ≥ 1 dose of COVID-19 vaccine between February and September 2021, matched with those who did not receive any COVID-19 vaccines up to September 2021. The infection cohort consisted of confirmed COVID-19 patients between January 2020 and March 2022, and people who were never infected up to March 2022. Both cohorts were followed until 15 August 2022. COVID-19 vaccine recipients and COVID-19 patients were 1:1 matched to their respective controls using propensity score. Hazard ratios (HRs) for incident diabetes were estimated using Cox regression models. Results: In the vaccination cohort, we included 167337 CoronaVac and 158378 BNT162b2 recipients with their respective 1:1 matched control. 442 (0.3%) CoronaVac recipients and 693 (0.4%) BNT162b2 recipients were COVID-19 survivors. Upon median follow-up (FU) of 13 months (IQR 11-14), CoronaVac or BNT162b2 vaccination was not associated with increased risks of incident diabetes (CoronaVac: HR=1.00 [95%CI 0.96-1.04]; BNT162b2: HR=0.86 [95%CI 0.83-0.90]), regardless of type 1 or 2. In the infection cohort, we included 145199 COVID-19 patients and 145199 matched controls. Among COVID-19 survivors, 60348 (41.6%) were fully vaccinated and 25792 (17.8%) did not receive any COVID-19 vaccines. Upon median FU of 5 months (IQR 5-6), 2109 COVID-19 patients (all type 2 diabetes) and 1775 non-COVID-19 people (one case of type 1 diabetes) were diagnosed with diabetes following SARS-CoV-2 infection. SARS-CoV-2 infection was associated with significantly higher risk of incident diabetes (1.45% vs 1.22%, HR=1.23 [95%CI 1.15-1.31]) regardless of the predominant circulating variants (non-Omicron, HR=1.87 [95%CI 1.35-2.59]; Omicron, HR=1.21 [95%CI 1.13-1.29]), albeit lower with Omicron variants (p for interaction=0.009). Subgroup analysis showed that fully vaccinated COVID-19 survivors did not have increased risk of incident diabetes (HR=1.01 [95%CI 0.90-1.12]). Conclusions: COVID-19 vaccination was not associated with increased risk of incident diabetes. The risk of incident diabetes increased following SARS-CoV-2 infection, mainly type 2 diabetes. The excess risk was lower, but still statistically significant, for Omicron variants. Fully vaccinated individuals might be protected from the risk of incident diabetes following SARS-CoV-2 infection.
Presentation: Sunday, June 18, 2023