Bone mineral density improvement after successful parathyroidectomy in pre- and postmenopausal women with primary hyperparathyroidism: a prospective study.

The aim of this study was to evaluate the short-term (1 year) changes of the lumbar spine (L2-L4) bone mineral density (LS-BMD) after parathyroidectomy (PTx) in pre- and postmenopausal women with primary hyperparathyroidism (PHPT). A series of 48 women (median age 56 years, range 23-82 years) with confirmed PHPT were prospectively enrolled in the study. Patients who received both oral contraceptives less than 2 years before the diagnosis and estrogen replacement therapy have previously been excluded. All patients underwent LS-BMD by dual energy x-ray absorptiometry before surgery. Patients were divided into two groups: group A (n = 12) premenopausal, and group B (n = 36) postmenopausal patients. The LS-BMD was repeated 12 months after successful PTx. Basal LS-BMD (0.852 +/- 0.061 vs. 0.748 +/- 0.142 g/cm(2)), serum calcium (2.95 +/- 0.23 vs. 2.94 +/- 0.26 mmol/L), creatinine (69.2 +/- 17.5 vs. 82.0 +/- 24.2 micromol/L), alkaline phosphatase (107.4 +/- 43.6 vs. 151.3 +/- 95.7 U/L), osteocalcin (28.6 +/- 9.3 vs. 28.2 +/- 8.3 microg/L), and PTH (192.7 +/- 133.2 vs. 175.2 +/- 132.1 ng/L) levels did not differ significantly (P = NS) between groups. The 1-year LS-BMD was 0.921 +/- 0.048 and 0.825 +/- 0.151 g/cm(2) in group A and B, respectively. In group B patients, the 1-year LS-BMD value did not improve significantly (P = NS), while in group A patients the difference between basal and postsurgical LS-BMD was significant (P < 0.01). In conclusion, PTx should be considered for all patients with PHPT and loss of bone density, but in premenopausal patients a greatest improvement of BMD may be found, suggesting the need of endogenous estrogens in complete lumbar bone recovery after surgery.