COVID-19: Clinical features and outcomes in unvaccinated 2-dose and 3-dose vaccinated against SARS-CoV-2 patients with systemic autoimmune and autoinflammatory rheumatic diseases

Clinical data on vaccinated patients with coronavirus disease 2019 (COVID-19) who have systemic autoimmune and autoinflammatory rheumatic diseases (SAARD) are limited. This observational study aimed to report the clinical features and outcomes of COVID-19 among cases with SAARD that were unvaccinated or were 2- and 3-dose vaccinated against SARS-CoV-2 and were consecutively recorded by the treating physician. Unvaccinated and 2- and 3-dose vaccinated patients were compared in terms of COVID-19 symptomatology, hospitalizations, oxygen supplementation requirements, and death rates. From the beginning of the pandemic to February 15, 2022, 134 vaccine-naïve COVID-19 cases were recorded among our study cohort. From March 1, 2021 to February 15, 2022, 89 2-dose vaccinated and 105 3-dose vaccinated patients who were infected with SARS-CoV-2 ≥14 days after the second dose were included. The hospitalization rate was higher in the unvaccinated (n = 36, 26.9%) than in the 2-dose (n = 13, 14.6%, p = 0.03) or 3-dose (n = 5, 4.8%, p < 0.001) vaccinated patients. Severe/critical COVID-19 cases requiring oxygen supplementation were the least among 3-dose vaccinated (n = 4, 3.8%) compared to both 2-dose vaccinated (n = 12, 13.5%, p = 0.018) and unvaccinated (n = 25, 18.7%, p < 0.001) patients. ICU admission and death rates were similar among unvaccinated (n = 5, 3.7% and n = 3, 2.2%, respectively) and 2-dose vaccinated patients (n = 4, 4.5%; and n = 2, 2.2%, respectively), while no 3-dose vaccinated patients died or required ICU admission. Logistic regression analysis revealed a significant inverse association between 3-dose vaccination and severe/critical COVID-19 (OR = 0.078, 95% CI: 0.022–0.273, p < 0.001). In conclusion, these findings argue in favor of booster vaccination against SARS-CoV-2 in patients with SAARD.