BODY-WEIGHT AND BONE-MINERAL DENSITY IN POSTMENOPAUSAL WOMEN WITH PRIMARY HYPERPARATHYROIDISM

Objective: To assess bone mineral density and body composition in post menopausal women with primary hyperparathyroidism. Design: Cross-secti onal study with an age-matched control group. Setting: University teac hing hospital. Patients: 41 postmenopausal women with mild primary hyp erparathyroidism and 43 eucalcemic, age-matched controls. Measurements : Total body, lumbar spine, and proximal femoral (femoral neck, Ward's triangle, and trochanter) bone mineral density; body composition; and fat distribution were measured using dual-energy x-ray absorptiometry . Results: Women with primary hyperparathyroidism were heavier (75.5 k g compared with 66.3 kg; difference, 9.2 kg [95% Cl, 3.7 to 14.7 kg]; P = 0.002), had a higher fat mass (33.3 kg compared with 26.1 kg; diff erence, 7.2 kg [Cl, 3.0 to 11.4 kg]; P = 0.001), and had a more androi d pattern of fat distribution (android-to-gynoid fat ratio, 1.05 compa red with 0.84; difference, 0.21 [Cl, 0.1 to 0.32]; P = 0.0004) than th e controls. Unadjusted bone mineral density was similar in patients an d controls at all sites: total body, 0.990 compared with 1.023 g/cm(2) (difference, 0.033; Cl, -0.004 to 0.070); posteroanterior lumbar spin e, 1.032 compared with 1.018 g/cm(2) (difference, 0.014; Cl, -0.031 to 0.059); lateral lumbar spine, 0.569 compared with 0.528 g/cm(2) (diff erence, 0.041; Cl, -0.022 to 0.104); femoral neck, 0.799 compared with 0.825 g/cm(2) (difference, 0.026; Cl, -0.072 to 0.124); Ward's triang le, 0.653 compared with 0.677 g/cm(2) (difference, 0.024; Cl, -0.035 t o 0.089); trochanter, 0.734 compared with 0.733 g/cm(2) (difference, 0 .001; Cl, -0.024 to 0.026); and arms, 0.720 compared with 0.739 g/cm(2 ) (difference, 0.019; Cl, -0.015 to 0.053). After adjustment for body weight, bone mineral density in women with primary hyperparathyroidism was lower than that in controls for total body (P = 0.0004), femoral neck (P = 0.001), Ward's triangle (P = 0.01), trochanter (P = 0.02), a nd arms (P = 0.0006). Spinal bone mineral density did not differ betwe en groups. Conclusions: Body weight, total body fat mass, and proporti on of android fat are increased in postmenopausal women with primary h yperparathyroidism these unexplained factors may be relevant to the in creased incidence of cardiovascular disease in this condition. Unadjus ted bone mineral density values are similar in patients with primary h yperparathyroidism and in controls, suggesting that this condition is not associated with an increased risk for fracture.