Objective: To assess coronavirus disease 2019 (COVID-19) booster uptake and vaccine effectiveness (VE) in reducing COVID-19 hospitalization in persons with systemic autoimmune and rheumatic diseases (SARDs).
Methods: Adult patients with SARDs receiving disease-modifying antirheumatic drugs at 4 health systems in the United States were identified retrospectively. Exposures were (1) receipt of an additional dose of monovalent COVID-19 vaccine prior to January 1, 2022, with follow-up to August 31, 2022; and (2) receipt of bivalent COVID-19 vaccine between September 1, 2022 and August 31, 2023.
Results: Among 201,165 patients with SARDs, 126,756 (63%) had received 1 monovalent booster as of January 1, 2022. During 94,842 person-years (PY) of follow-up, the COVID-19 hospitalization rate was 15.6 per 1000 PY among those who had received a monovalent booster vs 20.1 per 1000 PY among those who had not, with an adjusted VE of 38% (95% CI 31-44%) and a number needed to vaccinate of 267 (95% CI 230-325). Among 246,991 patients with SARDs with 233,622 PY of follow-up in the bivalent study period, the COVID-19 hospitalization rate was 7.9 per 1000 PY for the 87,906 (36%) patients who received the bivalent vaccine vs 10.2 per 1000 PY for the patients who did not. The adjusted VE of the bivalent vaccine was 32% (95% CI 24-39%) with a number needed to vaccinate of 617 (95% CI 500-838).
Conclusion: COVID-19 booster vaccinations provided significant protection against severe COVID-19 in persons with SARDs. Thus, increasing vaccine uptake should be prioritized in this high-risk immunocompromised population.
Keywords: SARS-CoV-2; bivalent; breakthrough infection; hospitalization; monovalent; systemic autoimmune rheumatic diseases.
Copyright © 2025 by the Journal of Rheumatology.