Osteopenia in rheumatology practice: pathogenesis and therapy.

Postmenopausal osteoporosis has a multifactorial pathogenesis related to decreases in bone mass, calcium intake, and circulating estrogen levels. Therapy with supplemental calcium, estrogen, fluoride, anabolic steroids, and calcitonin is discussed. Corticosteroid-induced osteopenia is in part related to a decrease in intestinal calcium absorption and therapy with supplemental vitamin D and calcium may favorably alter the outcome. The osteopenia of rheumatoid arthritis appears to be a diffuse process, with increased metabolic bone activity at sites that are remote from the areas of active synovitis.