INTERLEUKIN-1-BETA, HAND AND FOOT BONE-MINERAL CONTENT AND THE DEVELOPMENT OF JOINT EROSIONS IN RHEUMATOID-ARTHRITIS

Objective-To assess the relationship between plasma levels of the cyto kine interleukin-1 beta (IL-1 beta) and the progression of rheumatoid arthritis (RA). Methods-Two subgroups of patients, one with persistent ly raised ESR (> / = 50 mm/ hour, n = 16, group A) and one with persis tently low ESR (< / = 28 mm/hour), n = 18, group I) were chosen to rep resent stable extremes of inflammatory activity from a prospective stu dy of 106 patients with active RA studied over one year in a single ce ntre. The change from baseline in hand, foot and calcaneal bone minera l content measured by single photon absorptiometry and radiographic sc ore of joint damage was measured over 12 months, together with plasma IL-1 beta and erythrocyte sedimentation rate. Results-Significant prog ression of joint damage occurred in both subgroups over one year (p < 0.0001, paired t test) though progression was significantly less in th e subgroup with low ESR (p < 0.05, ANOVA). Hand and foot bone mineral content decreased by almost 10% in the subgroup with raised ESR (p < 0 .005, paired t test). Stepwise Linear regression analysis revealed sig nificant independent relationships between radiographic progression ov er one year and plasma IL-1 beta and ESR (multiple R 0.674, F = 11.64, p < 0.0002). No such relationships were observed for changes in bone mineral content parameters. Conclusions-Plasma IL-1 beta levels correl ate weakly with progression of joint damage though not with loss of pe ripheral bone density in RA. A significant reduction in peripheral bon e mineral content occurs over one year in patients with active RA with persistently raised ESR.