COVID-19 Vaccination May Increase Gout Flares Among Patients With Infrequent Flares

Vaccination for COVID-19 may be associated with increased gout flares, specifically among patients with infrequent flares, according to study findings published in Arthritis Care and Research (Hoboken).

Investigators assessed the risk for gout flares following vaccination against COVID-19 among patients with different levels of flare burden.

A prospective cohort study was conducted including 2 groups of patients with gout: those with infrequent flares (defined as 1 or fewer flares per year) and those with frequent flares (defined as at least 2 flares per year). Included patients had not received any doses of the COVID-19 vaccine and their disease was managed with urate-lowering therapy. Patients were followed-up for 12 weeks after study enrollment or initial vaccine dose.

The primary study outcome was incidence of gout flares based on baseline burden of flare frequency.

A total of 530 patients (100% men) were included in the analysis; 308 (58.1%) reported infrequent flares and 222 (41.9%) reported frequent flares at baseline. In addition, 248 patients (142 with infrequent flares and 106 with frequent flares) received 2 doses of COVID-19 vaccination.

After the 12-week follow-up period, 36.8% of all patients (17.9% with infrequent flares and 63.1% with frequent flares) experienced a gout flare.

COVID-19 vaccination was associated with a 2.82-fold increase (95% CI, 1.50-5.30) in cumulative flare incidence among the infrequent flare group at the end of the study period. No significant change in flare incidence was noted among the frequent flare group (odds ratio [OR], 0.81; 95% CI, 0.46-1.42; P =.46).

Among the infrequent flare group, flare incidence during the last 4 weeks of follow-up decreased significantly only among patients who were vaccinated (P =.017).

Multivariate analyses revealed 3 factors were found to be independently associated with increased risk for gout flare among the infrequent flare group: 1) vaccination (OR, 2.82; 95% CI, 1.50-5.30; P =.001), 2) flare occurring during the previous year (OR, 1.95; 95% CI, 1.03-3.71; P =.04), and 3) high body mass index (OR, 1.09; 95% CI, 1.00-1.18; P =.03).

Among the frequent flare group, baseline serum urate levels were an independent risk factor for an increase in flares (OR, 1.23; 95% CI, 1.05-1.45; P =.012).

Study limitations included the single-center design, potential recall bias, lack of data on the effects of messenger RNA vaccinations specifically, and lack of generalizability due to the all-male cohort.

While COVID-19 vaccination was associated with an increased incidence of gout flares among patients with infrequent flares, the study authors noted, “Gout flares occurred mostly within the first 4 weeks after the first injection of vaccine, and dropped to the same level as in the unvaccinated participants at 8-12 weeks.”