COVID-19 booster may cause transient glycaemic elevations in T1D

Individuals with type 1 diabetes (T1D) may experience mild, temporary glycaemic elevations following receipt of a COVID-19 booster vaccine, according to a study.

For the study, 21 participants with T1D, participants wore blinded Dexcom G6 Pro continuous glucose monitors for 10 days. All participants received a COVID-19 booster vaccine after a baseline period, and subsequent changes in glycaemic indices were assessed.

Of the participants, 38 percent received mRNA-1273 booster vaccine and 62 percent received BNT162b2 booster vaccine. Mean glucose level at baseline was 162.9 mg/dL, which rose significantly to 172.8 mg/dL at day 2 (p=0.04) and to 173.1 mg/dL at day 3 (p=0.02) postvaccination.

Additionally, there were elevations in insulin resistance observed at day 2 (p=0.03).

The increases in glucose levels and insulin resistance did not differ by the type of booster vaccine received.

In individuals with T1D, inflammation can lead to hyperglycaemia, according to researchers. They explained that vaccines are designed to trigger the body’s immune system, and booster vaccines can cause an even stronger immune response.

The findings underscore the potential need for increased glucose testing vigilance after vaccination, because although the glucose elevations are usually mild, a few individuals may have profound exacerbations, the researchers said.

They called for additional studies to examine the effects of other vaccines.