TNF Inhibitors, Other Factors Increase Risk of Extraarticular RA
Patients with rheumatoid arthritis (RA) who are treated with tumor necrosis factor (TNF) inhibitors face a slightly higher risk of developing severe extraarticular RA, according to a recent study. Additional predictors of extraarticular RA include male sex, positive rheumatoid factor (RF), long disease duration, and greater disability.
In their study, the researchers assessed a cohort of 1977 patients with RA. Patient data was obtained via clinical records, and cases of severe extraarticular RA were identified. Information on TNF exposure was obtained from a regional register.
_______________________________________________________________________________________________________________
RELATED CONTENT
Study Details Benefits of Early Treatment for Rheumatoid Arthritis
New Blood Test Determines Rheumatoid Arthritis Risk
_______________________________________________________________________________________________________________
The researchers analyzed patient exposure to TNF inhibitors in a time-dependent fashion in order to compare incidence of severe extraarticular RA in TNF-exposed patients with incidence among unexposed patients. Additionally, potential predictors of RA were assessed via Cox regression models.
Results indicated that, among patients treated with TNF inhibitors, 17 developed new onset of severe extraarticular RA in 2400 person-years (PY) at risk, vs 104 in 15.599 PY among patients who were not treated with TNF inhibitors. This corresponded to an incidence rate ratio of 1.06. However, the hazard ratio for extraarticular RA in anti-TNF-treated patients was 1.21, after adjusting for age and sex. Findings were similar in models adjusted for the time-dependent Health Assessment Questionnaire and propensity for anti-TNF treatment.
Additionally, the researchers found that predictors of extraarticular RA included male sex, positive RF, long disease duration, and greater disability.
“This study suggests that patients treated with TNF inhibitors are at a slightly increased risk of developing severe [extraarticular RA],” the researchers concluded. “RF-positive patients with disabling disease of long duration were more likely to develop severe [extraarticular RA].”
—Christina Vogt
Reference:
Theander L, Nyhäll-Wåhlin B-M, Nilsson J-Å, et al. Severe extraarticular manifestations in a community-based cohort of patients with rheumatoid arthritis: risk factors and incidence in relation to treatment with tumor necrosis factor inhibitors. J Rheumatol. 2017;44(7):981-987. https://doi.org/10.3899/jrheum.161103.
