To describe the treatment profile of multimorbid patients with rheumatoid arthritis (RA) in contrast to patients with RA only.
COMORA (Comorbidities in Rheumatoid Arthritis) is a cross-sectional, international study assessing morbidities, outcomes, and treatment of patients with RA. Patients were grouped according to their multimorbidity profile assessed by a counted multimorbidity index (cMMI). Treatment for RA was categorized as use of biologic disease-modifying antirheumatic drugs (bDMARD), in particular tumor necrosis factor inhibitors (TNFi), synthetic DMARD (sDMARD) use only, nonsteroidal antiinflammatory drug (NSAID) use, and corticosteroid use. Logistic regression models were performed to determine the OR of bDMARD, TNFi, sDMARD, NSAID, or corticosteroid use based on a patient's cMMI and global region after adjusting for age, disease activity, disease duration, educational level, and previous DMARD therapy.
Out of 3920 patients, 32.7% received bDMARD; 59.9% sDMARD only, 51.1% used concomitant NSAID, and 54.8% used corticosteroid. Regional differences were observed with the most frequent use of bDMARD in the United States (46.5%) and lowest in North Africa (9%). After adjusting for confounders in logistic regression, the OR for bDMARD use was reduced for each additional morbidity (OR 0.89, 95% CI 0.83-0.96). Similar results were found for TNFi (OR 0.91, 95% CI 0.84-0.99), whereas the OR for use of sDMARD was increased (1.13, 95% CI 1.05-1.22). No significant change of OR was found for NSAID or corticosteroid use.
In this study, the odds of bDMARD use decreases 11% for each additional chronic morbid condition after adjustment for regional differences, disease activity, and other covariates.