Rheumatoid arthritis: determination of pain characteristics and comparison of RAI and VAS in its measurement

The purposes of this study were to determine pain characteristics in female patients with rheumatoid arthritis (RA) and to determine the relationship between the outcome of the Ritchie Articular Index (RAI) and pain intensity as measured by the visual analogue scale (VAS). The sample consisted of 30 female patients with a definite diagnosis of RA and a functional capacity of class II. The results indicated that the pain fluctuated during the day. The intensity level of present pain was lower than that of usual pain. Eight patients reported that their worse pain occurred several times/day. Ache was the word most frequently chosen by the subjects to denote their pain sensations. A high correlation r = 0.86 (P < 0.01) was found between the scores of RAI and present pain on the VAS. This finding suggests that the pain in RA is associated with the hyperalgesic state induced by the inflammatory condition associated with RA. There was no significant correlation between blood tests like ERS, WBC and VAS or RAI.