PATIENTS WITH CELIAC DISEASE HAVE NO INCREASED RATE OF ADVERSE EVENTS AFTER COVID-19 VACCINE ADMINISTRATION COMPARED WITH NON-CELIAC CONTROLS

ABSTRACT

Background: A recent study showed that CeD patients have greater hesitancy in receiving the COVID-19 vaccine, mainly due to fear of adverse events. It is unclear if the rate of adverse events post-vaccine administration is higher in CeD compared to non-celiac population. Aims: To assess the prevalence of adverse events related to COVID-19 vaccine administration in patients with CeD compared to non-CeD controls, and to explore factors that predict the risk of adverse events related to COVID-19 vaccine. Methods: This is a preliminary analysis of an ongoing study conducted at McMaster Adult Celiac Disease Clinic. We collected data prospectively in a cohort of adult patients with a diagnosis of CeD attending our clinic and compared with non-CeD controls (university personnel). CeD diagnosis was based on serology, biopsy, and HLA DQ2/DQ8 in discrepant cases. Data collected included demographics, CeD activity through serology, adherence to the gluten-free diet (GFD), prior COVID-19 infection, vaccine type and status, and any adverse events. Mild adverse events were classified as pain at the site, fatigue, fever/chills, nausea, headaches. Severe adverse events included anaphylaxis, thrombosis, myocarditis/pericarditis, and hospitalization or emergency visits due to vaccination. Data were expressed as median [IQR] for continuous variables and n/N (%) for categorical variables. Mann-Whitney U test and Fisher exact test were performed using SPSS (v26, IBM Corp) to assess differences between groups and logistic regression to assess predictors of adverse events. Results: An interim analysis was performed in 53 patients with CeD (25% male;median age of 34[25] years) and 46 controls (37% male;median age of 41[22] years). There were no differences in sex between CeD and controls, however, controls were older than CeD (p=0.04). Fifty-five % of CeD patients were strictly adherent with a GFD. There was no difference in the rate of COVID-19 infection between CeD and controls. All CeD patients and controls reported receiving two doses of COVID-19 vaccines. Eighty-three % of CeD received the same vaccine type in both doses, and 17% mixed vaccines vs 81% and 19% respectively for controls. There were no severe adverse events reported by CeD or controls. The most common mild adverse events reported in CeD and controls included pain at the injection site (27% vs 64%;p <0.001) and fatigue (11% vs 46%;p<0.001). Celiac activity, age, sex, or vaccine type did not predict adverse events in CeD patients for either dose. Conclusions: In this preliminary analysis, administration of COVID-19 vaccines did not lead to severe adverse and less mild adverse reactions in patients with CeD compared to non-CeD controls. These results should be confirmed in a larger population, and ideally, in a future multicentre study involving pediatric and adult populations from different countries.