Risk factors associated with short-term adverse events after SARS-CoV-2 vaccination in patients with immune-mediated inflammatory diseases

BACKGROUND: Studies have suggested incremental short-term adverse events (AE) after repeated vaccination. In this report, we assessed occurrence and risk factors for short-term AEs following repeated SARS-CoV-2 vaccination in patients with various immune-mediated inflammatory diseases (IMIDs). METHODS: Self-reported daily questionnaires on AEs during the first 7 days after vaccination were obtained of 2259 individuals (2081 patients and 178 controls) participating in an ongoing prospective multicenter cohort study on SARS-CoV-2 vaccination in patients with various IMIDs in the Netherlands (T2B-COVID). Relative risks were calculated for potential risk factors associated with clinically relevant AE (rAE), defined as AE lasting longer than 2 days or impacting daily life. RESULTS: In total, 5454 vaccinations were recorded (1737 first, 1992 second and 1478 third vaccinations). Multiple sclerosis, Crohn’s disease and rheumatoid arthritis were the largest disease groups. rAEs were reported by 57.3% (95% CI 54.8–59.8) of patients after the first vaccination, 61.5% (95% CI 59.2–63.7) after the second vaccination and 58% (95% CI 55.3–60.6) after the third vaccination. At day 7 after the first, second and third vaccination, respectively, 7.6% (95% CI 6.3–9.1), 7.4% (95% CI 6.2–8.7) and 6.8% (95% CI 5.4–8.3) of patients still reported AEs impacting daily life. Hospital admissions and allergic reactions were uncommon (<0.7%). Female sex (aRR 1.43, 95% CI 1.32–1.56), age below 50 (aRR 1.14, 95% CI 1.06–1.23), a preceding SARS-CoV-2 infection (aRR 1.14, 95% CI 1.01–1.29) and having an IMID (aRR 1.16, 95% CI 1.01–1.34) were associated with increased risk of rAEs following a vaccination. Compared to the second vaccination, the first vaccination was associated with a lower risk of rAEs (aRR 0.92, 95% CI 0.84–0.99) while a third vaccination was not associated with increased risk on rAEs (aRR 0.93, 95% CI 0.84–1.02). BNT162b2 vaccines were associated with lower risk on rAEs compared to CX-024414 (aRR 0.86, 95% CI 0.80–0.93). CONCLUSIONS: A third SARS-CoV-2 vaccination was not associated with increased risk of rAEs in IMID patients compared to the second vaccination. Patients with an IMID have a modestly increased risk of rAEs after vaccination when compared to controls. Most AEs are resolved within 7 days; hospital admissions and allergic reactions were uncommon. TRIAL REGISTRATION: NL74974.018.20, Trial ID: NL8900. Registered on 9 September 2020. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12916-022-02310-7.