Rheumatoid Arthritis and Bone Mineral Density in Elderly Women. The Study of Osteoporotic Fractures Research Group

Previous studies have suggested that women with rheumatoid arthritis (RA) have decreased bone mineral density (BMD) in both the appendicular and axial skeleton. The purpose of this investigation was to determine the association of RA and BMD from a community-based sample of ambulatory Caucasian women age 65 and over. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the hip and lumbar spine and by single photon absorptiometry (SPA) at the distal radius and calcaneus. Study subjects included 120 postmenopausal women with RA who were further classified according to corticosteroid use, i.e., never users, current users, and ex-users, and 7966 age-similar controls. Elderly women with RA had a lower age-adjusted bone density of the distal radius, calcaneus, hip, and lumbar spine. Women with RA who were current users of steroids had the lowest BMD at both appendicular sites and at the hip, but those who never used steroids also had a significantly decreased BMD at all sites. The BMD of women with RA who had never used steroids remained significantly decreased at the distal radius, calcaneus, and hip after adjustment for age, BMD determinants, and functional outcomes of RA. Functional outcomes of RA largely accounted for the lower BMD of women who were currently using steroids. Women with RA have lower appendicular and axial bone mass that is not attributable to the use of steroids. Those currently taking steroids have even lower appendicular and axial bone mass that may reflect their poorer functional outcome and is likely to increase the risk of fractures.(ABSTRACT TRUNCATED AT 250 WORDS)