Vertebral Fracture Assessment in postmenopausal women with post-surgical hypoparathyroidism

CONTEXT Hypoparathyroidism is a rare endocrine disorder whose skeletal features include suppression of bone turnover, greater volume and width of the trabecular compartment. Few and inconsistent data are available on the prevalence of vertebral fractures (VF). OBJECTIVE To evaluate the prevalence of VF assessed by vertebral fracture assessment (VFA) in postmenopausal women with chronic post-surgical hypoparathyroidism. DESIGN Cross-sectional study. SETTING Ambulatory referral center. PATIENTS OR OTHER PARTICIPANTS Fifty postmenopausal women (mean age 65.4 ± 9 years) with chronic post-surgical hypoparathyroidism and 40 age-matched healthy postmenopausal women (mean age 64.2 ± 8.6). MAIN OUTCOME MEASURES Lumbar spine, femoral neck and total hip BMD were measured by dual X-ray absorptiometry (DXA) (Hologic Inc., USA) in all subjects. Site-matched spine TBS was calculated by TBS iNsight (Medimaps, Switzerland). Assessment of VF was made by VFA (iDXA, Lunar GE, USA) using the semiquantitative method and the algorithm-based qualitative assessment. RESULTS All-site BMD values were higher in the hypoparathyroid vs the control group. By VFA, we observed a 16% prevalence of VF in hypoparathyroid women vs 7.5% in control subjects. Among those with hypoparathyroidism who fractured, 5 (62.5%) had grade 1 wedge, 2 (25%) had grade 2 wedge, and 1 (12.5%) grade 2 wedge and grade 2 biconcave VF. In the hypoparathyroid group, among those with VFs, 57% had symptoms of hypoparathyroidism 32% among those without VF. CONCLUSION We demonstrate for the first time that in postmenopausal women with chronic postsurgical hypoparathyroidism, VFs are demonstrable by VFA despite normal BMD.