Safety and health care utilization following COVID-19 vaccination (BNT162b2) among children and youth with juvenile idiopathic arthritis and inflammatory bowel disease: A population-based study

Objectives To evaluate among Ontario children and youth (<16 years old) with juvenile idiopathic arthritis (JIA) or inflammatory bowel disease (IBD), whether COVID-19 vaccines (Monovalent BNT162b2) were associated with adverse events of special interest (AESI) or health care utilization. Methods Using health administrative databases, all children/youth with JIA or IBD who received at least one vaccine were identified from November 2020 to December 2021 with follow-up until August 31, 2022. Self-controlled case series analyses were used to determine the relative incidence rates (RIR) of events in any 3-week period [AESI, Emergency Department (ED) visits, hospitalizations] and in any 1-month period [specialist visits] post-vaccine compared to control periods. Results We studied 1629 JIA and 1050 IBD patients. In the JIA cohort, the median age at vaccination was 12.0 years [Interquartile range (IQR): 10.0 to 14.0], and the median disease duration was 4.3 years (IQR: 2.0 to 7.5). By December 2021, 67.1% (n = 1093) received two doses and 24.1% (n = 393) received three doses. In the IBD cohort, the median age at vaccination was 13.0 (IQR: 11.0 to 14.0) with a median disease duration of 2.4 years (IQR: 1.1 to 4.8). Fifty-four percent (n = 565) received two doses and 36.3% (n = 381) received three doses. During risk periods, AESI was rarely reported. Relative to control periods, JIA and IBD patients demonstrated similar rates of hospitalizations [JIA: RIR: 0.76 (95% confidence interval [CI]: 0.25 to 2.33), IBD: RIR: 0.64 (95% CI: 0.29 to 1.41)], ED visits [JIA: RIR: 1.11 (95% CI: 0.77 to 1.59), IBD: RIR: 0.93 (95% CI: 0.61 to 1.43)], and specialist visits [JIA: RIR: 1.06 (95% CI: 0.89 to 1.26), IBD: RIR: 0.56 (95% CI: 0.22 to 1.43)]. Conclusions Overall, this study demonstrates the safety of the BNT162b2 vaccine in children/youths with JIA and IBD, with no associated increase in AESI or health care use.