Forearm DXA Increases the Rate of Patients With Asymptomatic Primary Hyperparathyroidism Meeting Surgical Criteria

Introduction: A reduction in bone mineral density (BMD) is common in primary hyperparathyroidism (PHPT), above all at cortical sites. Guidelines for the management of asymptomatic PHPT (aPHPT) recommend a BMD evaluation at the lumbar spine, hip, and forearm. Surgery is recommended for patients with a T-score less than or equal to -2.5 at any of these sites. However, a BMD evaluation at the forearm is not routinely performed. Aim: To evaluate the impact of measuring forearm BMD in the clinical management of aPHPT. Subjects and Methods: We retrospectively reviewed a prospective database of 172 patients with aPHPT, selecting the 116 patients in whom a dual x-ray absorptiometry (DXA) scan had been performed at all 3 sites. Results: Seventy-four out of 116 patients had a densitometric diagnosis of osteoporosis (OP) at any site, and the forearm was the only site involved in 13/74 (group A, 17.6% of osteoporotic patients and 11.2% of the whole aPHPT cohort). Patients belonging to groupAwere significantly older than the other aPHPT patients, whereas no difference was found in biochemical measurements. Six out of 13 patients belonging to group A (5.2% of the whole aPHPT cohort) fulfilled surgical criteria based only on a forearm T-score. Conclusions: DXA at 3 sites revealed OP at the forearm, but not at the other sites, in 11.2% of aPHPT patients. Half of these cases met surgical criteria based on this one factor alone. These patients did not show any clinical (except age) or biochemical differences from the other patients. The implementation of forearm DXA increases the rate of patients with aPHPT meeting surgical criteria.