EFFECTS OF MILD ASYMPTOMATIC PRIMARY HYPERPARATHYROIDISM ON BONE MASSIN WOMEN WITH AND WITHOUT ESTROGEN REPLACEMENT THERAPY

Primary hyperparathyroidism (HPT) presents most commonly as a mild ele vation of the serum calcium concentration in an asymptomatic individua l. There are conflicting data regarding the effects of mild primary HP T on bone mass. This cross-sectional study was conducted to examine th is question further and to determine whether estrogen replacement ther apy (ERT) in postmenopausal women with primary HPT might be beneficial . We measured bone mass in 59 women with mild asymptomatic primary HPT , of whom 43 (HPT) had never taken and 16 (estrogen-replaced HPT) were currently taking ERT. We also studied 84 healthy normocalcemic women who were not on ERT (controls) and 45 who were on ERT (estrogen-replac ed controls). After adjustment for age, height, and weight, mean bone mass values in the HPT group were significantly reduced in the midradi us (20%), distal radius (20%), lumbar spine (17%), and femoral neck (1 1%) compared with the controls. The estrogen-replaced HPT group had me an bone mass values greater than those in the HPT group, similar to th ose in the controls, and lower than those in the estrogen-replaced con trols. Mild asymptomatic primary HPT results in bone loss from both th e appendicular and axial skeleton, and ERT in postmenopausal women wit h primary HPT may ameliorate this loss.