Table 1:
Baseline characteristics (N = 285)*
| Variable | Mean (SD) or % |
|---|---|
| Age (years) | 54.70 (13.74) |
| Female | 82.1% |
| Caucasian | 74.7% |
| BMI (kg/m2) | 28.58 (6.62) |
| Seropositive, % | 78.3% |
| RA duration (years) | 9.97 (11.88) |
| Biologic DMARD use | 24.9% |
| Site, % of enrolled | |
| Brigham/MGH | 51.9% |
| Boston University | 10.2% |
| Michigan University | 19.3% |
| Johns Hopkins | 18.6% |
| Pain Catastrophizing Scale | 18.67 (13.56) |
| Pain Intensity (NRS 0–10) | 5.25 (2.29) |
| CDAI | 24.56 (14.25) |
| Patient global | 4.23 (2.44) |
| Physician global | 3.68 (2.28) |
| Swollen joint count | 5.26 (5.25) |
| Tender joint count | 10.89 (8.60) |
| CRP (mg/L) | 8.15 (12.45) |
| FSQ score | 11.22 (6.08) |
| WPI score | 5.95 (4.32) |
| SSS score | 5.27 (2.65) |
| QST | |
| Thumbnail PPT (kgf) | 3.67 (1.95) |
| Trapezius PPT (kgf) | 2.93 (1.65) |
| Wrist PPT (kgf) | 2.93 (1.59) |
| Knee PPT (kgf) | 5.41 (2.84) |
| Wrist TS | 13.06 (14.78) |
| Arm TS | 12.54 (14.63) |
| CPM | 1.40 (0.35) |
*
CDAI n=243; patient global n=243; thumbnail PPT, trapezius PPT, wrist PPT n=284; knee PPT n=283; wrist TS n=282; arm TS n=281; CPM n=279.
BMI body mass index; RA rheumatoid arthritis; DMARD disease-modifying anti-rheumatic drug; MGH Massachusetts General Hospital, NRS numeric rating scale; CDAI clinical disease activity index; CRP C-reactive protein; FSQ fibromyalgia survey questionnaire; WPI widespread pain index; SSS symptom severity score; QST quantitative sensory index; PPT pressure pain threshold; kgf kilogram force; TS temporal summation; CPM conditioned pain modulation