EFFECTS OF DISEASE AND CORTICOSTEROIDS ON APPENDICULAR BONE MASS IN POSTMENOPAUSAL WOMEN WITH RHEUMATOID-ARTHRITIS - COMPARISON WITH AXIAL MEASUREMENTS

The potential value of measurements of peripheral bone mass in rheumat oid arthritis (RA) as an assessment of long-term disease activity has recently received renewed attention. This study examines the effects o f RA and corticosteroid therapy on newer methods of measuring peripher al hone mass, comparing the results with dual-energy X-ray absorptiome try (DXA) at axial sites. Peripheral quantitative computed tomography of the radius, ultrasound of the calcaneus, and DXA of the hip and spi ne were compared between 29 controls and 46 women with RA of whom 25 w ere receiving low-dose corticosteroid therapy. Bone mass was significa ntly reduced in the RA groups for: (i) radial trabecular (36.1%) and t otal (15.6%) measurement sites; (ii) calcaneal ultrasound attenuation (31.7%) and velocity (6.6%); and (iii) femoral neck (15.4%) bone miner al density. Lumbar spine and radial cortical measurements were not sig nificantly affected. There were no significant differences between the RA groups. Disease activity and physical activity did appear to be re sponsible for much of the reduction in bone mass. These results demons trate that RA is associated with significant bone loss at the hip, rad ius and calcaneus, but not at the lumbar spine. In this small study, l ow-dose corticosteroids had little additional deleterious effect.