Published May 2, 2023
Transient Spike in Glucose Levels With COVID-19 Vaccines
Pharmacists should not be surprised by reports from vaccine recipients with diabetes that their glucose readings rose after getting the original COVID-19 vaccine series; however, a new study in the journal Diabetology & Metabolic Syndrome suggested that the brief glycemic change is not a cause for vaccine hesitancy. In fact, another recent study raises the possibility that vaccination could be protective against developing diabetes.
“Glycemic monitoring has become critical during the COVID-19 pandemic because of poor prognosis in diabetes,” the Taiwanese researchers wrote. “Vaccines were key in reducing the spread of infection and disease severity, but data were lacking on effects on blood sugar levels. The aim of the current study was to investigate the impact of COVID-19 vaccination on glycemic control.”
The researchers performed a retrospective study of 455 consecutive patients with diabetes who completed two doses of COVID-19 vaccination at a single medical center. One hundred and fifty-nine subjects received ChAdOx1 (ChAd) vaccines, 229 received Moderna vaccines, and 67 received Pfizer-BioNtech (BNT) vaccines.
The study team assessed laboratory measurements of metabolic values before and after vaccination; the type of vaccine and administrated antidiabetes drugs were analyzed to detect any independent risks associated with elevated glycemic levels.
The results indicated that the average glycosylated hemoglobin A1C (HbA1c) was raised in the BNT group from 7.09% to 7.34% (P = .012) and nonsignificantly raised in the ChAd (7.13-7.18%, P = .279) and Moderna (7.19-7.27%, P = .196) groups.
“Both Moderna and BNT groups had around 60% of patients with elevated HbA1c following two doses of COVID-19 vaccination, and the ChAd group had only 49%,” the authors reported.
With further analysis, receiving the Moderna vaccine was found to independently predict the elevation of HbA1c (odds ratio [OR] 1.737; 95% CI, 1.12-2.693, P = .014), while the use of sodium-glucose co-transporter 2 inhibitors (SGLT2i) for diabetes treatment was negatively associated with elevated HbA1c (OR 0.535; 95% CI, 0.309-0.927, P = .026), according to the study.
“Patients with diabetes might have mild glycemic perturbations following two doses of COVID-19 vaccines, particularly with mRNA vaccines,” the researchers advised. “SGLT2i showed some protective effect on glycemic stability. Hesitancy in having vaccinations should not be indicated for diabetic patients with respect to manageable glycemic change.”
The other recent study from Cedars-Sinai Medical Center in Los Angeles and Brigham and Women’s Hospital in Boston assessed the association of vaccination with risk of incident diabetes.
“In early phases of the COVID-19 pandemic, persons who recovered from infection had increased risks for new-onset cardiometabolic diseases, including diabetes, hypertension, and hyperlipidemia,” the authors wrote in the Journal of the American Medical Association Network Open. “In the current pandemic phase, which is dominated by less virulent Omicron variants, it remains unclear whether risks of cardiometabolic disease after COVID-19 infection persist or have become attenuated and whether vaccination status is associated with these risks.”
The study team conducted a large cohort study of 23,709 adult patients with one or more COVID-19 infections treated within the Cedars-Sinai Health System from March 2020 to June 2022. The participants had an average age of 47.4 years and 54% were women. The goal was to calculate the odds of a new cardiometabolic diagnosis occurring 90 days after versus 90 days before COVID-19 infection.
The results indicated that rates of new-onset diabetes, hypertension, hyperlipidemia, and benchmark diagnoses occurring in the 90 days after COVID-19 infection were higher than those before infection.
The odds for post infection were:
• Diabetes (2.35; 95% CI, 1.94-2.89; P <.001)
• Hypertension (1.54; 95% CI, 1.35-1.76; P <.001)
• Benchmark diagnoses (1.42; 95% CI, 1.25-1.61; P <.001)
• Hyperlipidemia (1.22; 95% CI, 1.03-1.47; P = .03).
In adjusted multivariable models, the researchers reported that the risk of new-onset diabetes (vs. benchmark) diagnosis occurring after versus before COVID-19 infection was significantly elevated (odds ratio [OR] 1.58; 95% CI, 1.24-2.02; P <.001), although the risks of hypertension and hyperlipidemia versus benchmark diagnoses were not.
The diabetes risk after infection was higher among unvaccinated patients (OR 1.78; 95% CI, 1.35-2.37; P <.001) than vaccinated (OR 1.07; 95% CI, 0.64-1.77; P = .80), but the authors advised that the interaction term between vaccination status and diabetes diagnosis was not statistically significant (OR 0.59; 95% CI, 0.34-1.06; P = .08). “There was no evidence of interaction by age, sex, or preexisting cardiovascular risk factors, including hypertension or hyperlipidemia,” the authors wrote. “Age, sex, and timing of index infection regarding the Omicron variant were not associated with an increased risk of a new cardiometabolic diagnosis before or after COVID-19 infection in any model.”
The study team suggested that the increased risk of diabetes with COVID-19 infection persisted as the Omicron variant became predominant, and the association remained even after accounting for temporal confounders. “Diabetes risk after COVID-19 infection was higher in unvaccinated than vaccinated patients, suggesting a benefit of vaccination,” the study noted. “Mechanisms contributing to postinfection diabetes risk remain unclear, although persistent inflammation contributing to insulin resistance is a proposed pathway.”
The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.
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