CLINICAL-PATTERN OF PAIN IN RHEUMATOID-ARTHRITIS

Objective. To evaluate whether rheumatoid arthritis (RA) is associated with a characteristic clinical pattern of pain which may be useful as a criterion to differentiate RA from other rheumatic diseases. Method s. 2300 patients from the ReumaLink data bank project with definite rh eumatic diseases were studied. Of these 907 patients (39.5%) fulfilled the ARA/ACR revised criteria for RA, while 1393 had rheumatic disease s other than RA. The following diagnostic attributes of pain were cons idered: localization, symmetry, continuity, modulation, relationship w ith time and with loads/movements, tenderness. Results. After a descri ptive analysis, some pain characteristics were selected individually a nd others were combined Only 8 variables were considered for a predict ive analysis. Univariate analysis showed that symmetric pain is the mo st potent discriminating item, with 82.2% sensitivity, 69.2% specifici ty, a 61% positive predictive value and a 83.3% negative predictive va lue. A higher probability of RA was present in patients with symmetric pain than in those with asymmetric pain (odds ratio = 7.8). A multiva riate analysis performed on 1627 patients showed that a specific clini cal pattern of pain (symmetrical pain, pain following joint pressure, mainly present at night or in the morning, continuous) could predict R A patients with a 68.9% likelihood. The lack of these symptoms exclude d RA with 92% probability. Conclusion. The clinical pattern of pain de fined by us cart predict RA with a 70% probability This value reaches 86% when the variables ''pain in a fixed joint'' and ''pain decreased by load/movements'' are added These results indicate that determining the clinical pattern of pain is a useful screening tool for suspected RA, in particular early ir? the disease course.