Association of COVID-19 vaccinations with osteoarthritis flares: A case-crossover study

People with osteoarthritis (OA) commonly experience flares. Whether COVID-19 vaccination triggers OA flares is unknown.

Adults with OA enrolled in a COVID-19 Rheumatology Registry were invited to participate in a case-crossover study. Vaccine data were ascertained from self-report and electronic health records (EHR). OA was identified using coding algorithms and validated via EHR. Participants reported flare and non-flare periods. Vaccine exposures in the 2-, 7-, and 14-day "lookback windows" prior to OA flares were compared to vaccine exposures during similar non-flare ("control") periods.

279 participants had validated OA, and 136 (49%) contributed at least one flare and one control period. Mean age was 68 years [SD ±8], 82% female, 87% White, 62% knee OA, 56% hip OA, 37% hand/wrist OA and 60% had >= one anatomic location of OA. 525 COVID-19 vaccine doses were recorded, and participants reported 374 OA flares: 30% were mild, 55% were moderate, and 14% were severe. OA flares were not associated with COVID-19 vaccination 2 or 7 days prior (odds ratios [OR] 0.69 [95% confidence interval (CI): 0.28, 1.66], OR 0.54 [95% CI: 0.27, 1.07], respectively). In the 14-day lookback window, fewer flares occurred after vaccination (OR 0.57 [95% CI: 0.34, 0.97], p=0.039). Analyses stratified on sex, age, knee or hand OA, vaccine brand, and dose showed no increased association between COVID-19 vaccination and OA flares.

The lack of positive association between COVID-19 vaccination and OA flare in any primary or secondary analysis provides reassurance regarding the use of COVID-19 vaccines in people with OA.