Individuals with both hand osteoarthritis (OA) and rheumatoid arthritis (RA) may have greater pain intensity, higher disease activity, and greater functional disability compared with patients with RA only, according to a study published in Clinical Rheumatology.
Demographic, comorbidity, and disease characteristics data were collected from patients who had RA and OA (n=39) or RA only (n=42) during a 1-time clinician visit. Disease activity was assessed with the Disease Activity Score 28-joints with erythrocyte sedimentation rate (ESR; DAS28-ESR), DAS28-C-Reactive Protein (DAS28-CRP), the Simplified Disease Activity Index (SDAI), and the Clinical Disease Activity Index. Based on the DAS-28 cutoff points, patients were categorized as being in remission (≤2.6) or having low (>2.6 and ≤3.2), moderate (>3.2 and ≤5.1), or high (>5.1) disease activity. The study’s primary outcome was pain intensity.
The cohort was comprised of a majority of women (94%) and had a median 13-year disease duration. Patients with RA plus OA vs RA only had a higher pain intensity (visual analogue scale [VAS] score, 70 mm vs 30 mm, respectively; P =.003), higher disease activity (3.89 vs 2.88, respectively; P =.001), and greater functional disability (Health Assessment Questionnaire Disability Index score, 0.82 vs 0.15, respectively; P =.01). A higher percentage of patients with RA plus OA had higher residual pain compared with patients with RA only (59% vs 29%, respectively; P =.006). Although there were no observable differences in disease activity categories between groups, a strong correlation was established between pain and disease activity (r2 = 0.69; P <.001).
Study limitations include the small sample size, recruitment of patients from a single geographic area, and the cross-sectional design.
“OA also causes increases in disease activity scores and is therefore an important factor in residual pain, possibly resulting in the exposure of patients to potentially harmful treatments rather than pain management alone,” noted the study
Ruiz-Medrano E, Espinosa-Ortega HF, Arce-Salinas CA. The effect of concomitant hand osteoarthritis on pain and disease activity in patients with rheumatoid arthritis [published online May 10, 2019]. Clin Rheumatol. doi:10.1007/s10067-019-04574-6