BONE-MINERAL DENSITY OF THE HAND IN RHEUMATOID-ARTHRITIS

Objective. To determine the reproducibility, accuracy, and linearity o f hand bone mineral content (BMC) measurements, and to evaluate the in fluence of hand posture; to determine the relationship of hand bone mi neral density (BMD) to generalized osteopenia in rheumatoid arthritis (RA); and to determine the elationship between hand BMD and disease se verity in early RA. Methods. Hand BMD was measured by dual-energy x-ra y absorptiometry (DXA). We studied 70 postmenopausal women with steroi d-treated PA (established RA), ages 49-79, and 20 age-matched healthy controls to determine the relationship to generalized osteoporosis; we also studied 20 patients ages 23-74 years with early RA to determine the relationship between disease severity and hand BMD. Results, Repro ducibility of hand BMD was to within 1%. In established RA, there was a greater decrease in juxtaarticular BMD (23 % at the hand) than in ge neralized BMD (16% at the femoral neck, 11% at the lumbar spine, and 1 1% total body) compared with that in age-matched controls. Hand BMD co rrelated with skeletal size and BMD at other skeletal sites. In establ ished RA, there was no effect of disease duration, disability, or ster oid therapy. In early RA, hand BMD correlated with age and disease act ivity. Conclusion. Measurement of hand BMD by DXA is accurate and prec ise. Hand BMD reflects BMD at other skeletal sites in patients with RA , and is a marker of disease severity in patients with early disease. It may be a sensitive marker of disease progression and response to th erapeutic intervention.