BNT162b2 vaccination in adolescents was associated with a low overall absolute risk of adverse events of special interest, with no significantly increased risk except for myocarditis (IRR 29.61 after second dose) and sleeping disturbances.
Cohort (n=274,881)
Does the BNT162b2 vaccine increase the risk of adverse events of special interest, including myocarditis, in adolescents aged 12-18?
In adolescents, BNT162b2 vaccination is associated with a significantly increased relative risk of myocarditis, particularly after the second dose, though the absolute risk remains low and the overall risk of other adverse events is not elevated.
Relative Risk: 1.3 (95% CI 0.87–1.95)
p-value: p=0.204
Accruing evidence suggests an increased risk of myocarditis in adolescents from messenger RNA COVID-19 vaccines. However, other potential adverse events remain under-researched. We conducted a retrospective cohort study of adolescents aged 12–18 with a territory-wide electronic healthcare database of the Hong Kong population linked with population-based vaccination records and supplemented with age- and sex-specific population numbers. Two age- and sex-matched retrospective cohorts were formed to observe 28 days following the first and second doses of BNT162b2 and estimate the age- and sex-adjusted incidence rate ratios between the vaccinated and unvaccinated. Thirty AESIs adapted from the World Health Organization’s Global Advisory Committee on Vaccine Safety were examined. Eventually, the first-dose cohort comprised 274,881 adolescents (50.25% received the first dose) and the second-dose cohort 237,964 (50.29% received the second dose). Ninety-four (34.2 per 100,000 persons) adolescents in the first-dose cohort and 130 (54.6 per 100,000 persons) in the second-dose cohort experienced ≥1 AESIs. There were no statistically significant differences in the risk of any AESI associated with BNT162b2 except myocarditis first-dose cohort: incidence rate ratio (IRR) = 9.15, 95% confidence interval (CI) 1.14–73.16; second-dose cohort: IRR = 29.61, 95% CI 4.04–217.07 and sleeping disturbances/disorders after the second dose (IRR = 2.06, 95% CI 1.01–4.24). Sensitivity analysis showed that, with myocarditis excluded as AESIs, no significantly elevated risk of AESIs as a composite outcome associated with vaccination was observed (P = 0.195). To conclude, the overall absolute risk of AESIs was low with no evidence of an increased risk of AESIs except myocarditis and sleeping disturbances/disorders.
Lai et al. (2022) conducted a cohort in Adverse events of special interest (AESI) following COVID-19 vaccination (n=274,881). BNT162b2 vaccine vs. Unvaccinated adolescents was evaluated on Any adverse event of special interest (AESI) after first dose (IRR 1.30, 95% CI 0.87-1.95, p=0.204). BNT162b2 vaccination in adolescents was associated with a low overall absolute risk of adverse events of special interest, with no significantly increased risk except for myocarditis (IRR 29.61 after second dose) and sleeping disturbances.