FRI690 Should Treatment For Osteoporosis Be Started In Patients With Primary Hyperparathyroidism Within The First Year After Parathyroidectomy?

Disclosure: K. Swe: None. A. Chiu: None. E. Pelley: None. Osteoporosis is one of the indications for parathyroidectomy in patients with primary hyperparathyroidism. Studies show the improvement of bone mineral density (BMD) in the lumbar spine and hip within the first year after parathyroidectomy. Therefore, the decision to treat osteoporosis has usually been delayed until a follow-up bone densitometry scan (DXA) at least one year after parathyroidectomy. To study the BMD changes with or without osteoporosis treatment till first follow-up DXA after parathyroidectomy, we retrospectively reviewed a prospective database of patients undergoing parathyroidectomy for primary hyperparathyroidism between 2010 to 2017 at our institution. We included both male and female patients between the ages 50 to 80, with a history of fragility fracture and/ or T score less than -2.4, and normal renal function. We excluded patients with persistent hyperparathyroidism post-surgery, osteoporosis medication within 3 years before surgery, and DXA performed outside of our facility. Patients who received osteoporosis medication between surgery and the first follow-up DXA were compared to those who underwent surgery alone. We compared the changes in BMD at the total hip and lumbar spine (L1-L4) between baseline and the first follow-up DXA for the two groups. Data was evaluated using a student’s t-test. A total of 386 patients underwent parathyroidectomy during the study period of which 92 patients met the inclusion criteria. Among them, 28 patients were treated after surgery and 64 patients had parathyroidectomy alone. The mean duration to treatment initiation after surgery was approximately 4 months (SD +/- 3 months), and the mean duration until the first follow-up DXA after the surgery was 17 months (SD +/- 8 months). There was no difference in the change of BMD at the total hip between two groups. Both increased by 0.01 g/cm(2) (p=0.74). However, there was a greater increase in BMD at the lumber spine for those treated (0.047 g/cm(2) increase) compared to surgery alone (0.019 g/cm(2) increase) (p=0.02). We concluded that initiation of osteoporosis treatment within the first year after parathyroidectomy led to similar BMD outcomes at the total hip, but the treatment group experienced greater gains in BMD at the lumbar spine compared to parathyroidectomy alone, in patients with primary hyperparathyroidism and osteoporosis. Presentation: Friday, June 16, 2023