Study authors theorized that the reduced effect could be due to disease-related or immunosuppressive treatment factors.
Patients with rheumatoid arthritis (RA) receiving disease-modifying antirheumatic drugs (DMARDs) showed reduced immune responses to the COVID-19 vaccine compared with controls, in a recent study published in Journal of Rheumatic Diseases.1
Patients with RA carry increased risks for developing infections, including COVID-19. Since the introduction of the COVID-19 vaccine, additional concerns have emerged regarding the potential of vaccine-induced RA flare-ups or other forms of autoimmune or inflammatory phenomena. As DMARDs have provided benefits to patients with RA, such as reducing and modulating inflammatory and immune system responses, researchers conducted a cross-sectional study to investigate lacking data on COVID-19 vaccine responses in patients with RA receiving DMARDs.
From May 2022 to April 2023, patients with RA receiving DMARDs were evaluated at 2 tertiary care centers. Patients with seropositive as well as seronegative status were accepted. Investigators gathered data on individual COVID-19 infection and vaccination histories, prescribed and administered medications (DMARDs), as well as scaling on the Disease Activity Score-28 (DAS28). Blood samples of 10 mL were also taken for examination of erythrocyte sedimentation rate (ESR), complete blood count, C-reactive protein (CRP), liver and renal function, and neutralizing antibodies for COVID-19.
In total, 103 patients with RA were recruited and compared with 185 controls. In the RA group, 42% of individuals had comorbidities—most commonly, hypothyroidism (16.5%). The RA group was also vaccinated against COVID-19 at rates of 79.6% compared with 91.3% in the controls. No controls had a history of COVID-19 infection, but 13.6% of patients with RA did. Most of the patients with RA were identified as having low disease activity (mean DAS28 of 2.9).
Researchers observed that patients with RA had overall higher mean levels of ESR and elevated IL-6 compared with controls (ESR: 26.0 vs 19.2; P = .0004; IL-6: 15.8 vs 3.7; P < .0001).
Each group registered positive results for antispike antibodies; this was significantly higher in controls compared with patients with RA (95.9 vs 89.5; P < .0001). Interestingly, in patients with RA, age was positively correlated with levels of anti-spike antibodies (P = .0015), but this was not significant in controls. Antibody status in groups using different amounts of DMARDs were statistically significant, especially between individuals on a 3-drug regimen compared with those on a single-drug regimen of hydroxychloroquine alone (P = .0192). The authors noted that neither the presence of comorbidities nor the type of COVID-19 vaccine received, prior infection, or booster status had a statistically significant effect on antibody concentration.
The authors noted the positive takeaway that patients with RA exhibited robust immune responses following their COVID-19 vaccination, although this response was reduced compared with controls. They theorized that this could be due to disease-related or immunosuppressive treatment factors, and advocated for future research to be conducted to analyze responses following second vaccination doses.