[Osteoporotic changes in rheumatoid arthritis].

Bone mineral density (BMD) in the distal 1/6 and 1/3 sites of the radius was measured by single photon absorptiometry in 58 female patients with rheumatoid arthritis, not treated with corticosteroids. Half of the patients showed lower values of BMD than those (mean--1SD) of age-matched controls. BMD decreased more significantly with advancement of destructive changes of radiocarpal joint in postmenopausal patients. There was a significant inverse correlation between BMD and duration of the disease. Decreasing rate of BMD was much higher in postmenopausal patients than in premenopausal patients. These results indicated rheumatoid arthritis was not universally associated with osteoporosis. Osteoporosis occurred much more frequently in postmenopausal patients with a long duration of the disease showing marked joint destruction. In premenopausal patients, bone loss was most common in the region of affected joints. But, bone loss in postmenopausal patients occurred not only in the periarticular bone but in the diaphyseal bone.