LOSS OF TRABECULAR BONE-MINERAL DENSITY IN SYSTEMIC LUPUS-ERYTHEMATOSUS

Objective. To evaluate trabecular bone mineral density (BMD) in young ambulatory female patients with systemic lupus erythematosus (SLE). Me thods. Bone mineral density (gm/cm2) at the lumbar vertebrae (L1-L4) a nd at the left femur (neck, trochanter, intertrochanter, and Ward's tr iangle) was measured by dual x-ray absorptiometry in 46 SLE patients ( mean age 31 years, mean disease duration 76 months) and in 108 healthy female controls (mean age 32 years). Twenty-two of the SLE patients w ere receiving corticosteroids (CS) at the time of the study. Results. Lumbar BMD in the SLE patients was less severely reduced than was BMD at the femoral sites, but the SLE group was closer to the lumbar fract ure threshold of 0.812 gm/cm2 than was the control group (P = 0.0009). There were no significant differences between the SLE patients curren tly being treated with corticosteroids and those who were not (P > 0.3 ). BMD at Ward's triangle and at the femoral neck was not significantl y reduced in the SLE patients. Total femoral BMD had a sensitivity of 76% and specificity of 62% in differentiating the SLE group from the c ontrols. The positive predictive value was 61% and the negative predic tive value was 89%. The prevalence of osteopenia in the SLE patients w as 25%. Conclusion. SLE causes significant trabecular bone loss, which is not due to corticosteroid therapy.