ABSTRACT
Background: Patients with rheumatoid arthritis (RA) may have impaired immu-nogenicity to COVID-19 vaccines. Objectives: To investigate the incidence of COVID-19 infection and hospitalisation in unvaccinated and vaccinated patients with RA compared with matched individuals;and secondarily in patients with RA according to DMARD treatment. Methods: Danish nationwide matched cohort study from January to October 2021. Patients with RA were identifed in DANBIO and matched 1:20 with individuals from the general population on age, sex, and vaccination status (month and exact type of vaccination). Primary and secondary outcomes were COVID-19 hospitalisation (Danish National Patient Register) and positive SARS-CoV2 PCR test (Danish COVID-19 Surveillance Register), respectively. Stratifed by vaccination status, incidence rates (IRs) per 1000 person years (PY) and comor-bidity-adjusted hazard ratios (aHRs) in cause-specifc Cox models were calculated with 95% confdence intervals. Using the Aalen-Johansen estimator, the cumulative incidence of COVID-19 hospitalisations was visualised according to RA and vaccine exposure status. Results: Regardless of vaccination status, patients with RA had increased incidence of COVID-19 hospitalisation compared to matched individuals (Table 1). However, the absolute risk was 0.20% for unvaccinated patients at 60 days and 0.08% for comparators, whereas it remained below 0.05% at 180 days of follow-up in both groups when fully vaccinated (Figure 1). Increased SARS-CoV2 infection rates were seen only among unvacci-nated patients with RA (Table 1). Unadjusted analyses showed increased incidence of COVID-19 hospitalisation among rituximab-treated compared with conventional DMARD treated: unvaccinated HR 4.71 (1.98 to 11.18) and vaccinated HR 11.69 (2.07 to 66.06). However, the proportions of patients with previous cancer and treated with prednisolone were higher among the rituximab treated. Conclusion: The incidence of COVID-19 hospitalisation was increased for both unvaccinated and vaccinated patients with RA compared with controls. Importantly, the parallel decreasing risk for patients with RA suggests a comparable relative beneft of vaccination. Less favourable outcomes among rituximab-treated warrant that this drug should be considered with extra care.
ABSTRACT
Background: Patients with small vessel vasculitis (SVV) and large vessel vas-culitis (LVV, including giant cell arteritis (GCA)) are considered at higher risk of infections compared to the general population, owing to their underlying condition and the use of immunosuppressive drugs. Thus, the risk of COVID-19 infection and related outcomes during the global pandemic is of immediate concern to rheumatologists worldwide. Objectives: To estimate the incidence of COVID-19 hospitalisation in patients with vasculitis, and to evaluate the impact of glucocorticoid treatment on the outcome between March 2020 and February 2021. Methods: With use of the Danish nationwide registers, a cohort of patients with LVV and SVV, respectively, and general population controls (GPCs) matched on age and gender was established. Hazard ratios (HR) for COVID-19 hospitalisation was estimated. National COVID-19 surveillance data was used to calculate the odds ratio (OR) of having had a positive SARS-CoV2 PCR test. Lastly, a nested case-control design and conditional logistic regression was used to estimate the impact of glucocorticoids on the risk of hospitalisation. Results: Patients with SVV (n=1090) had an increased incidence of COVID-19 hospitalisation compared with GPCs (comorbidity-adjusted HR 2·73;95% CI 1·64-4·55), whereas no increased risk was seen in patients with LVV. Patients with vasculitis had similar likelihoods of having had a positive PCR test as GPCs. Glucocorticoids did not increase the HR of hospitalisation among patients with LVV or SVV. Conclusion: Patients with SVV were more likely to be admitted with COVID-19 than the GPCs. The impact of glucocorticoid treatment on the risk of hospitalisation needs further investigation.