Denosumab for osteoporosis in patients with primary hyperparathyroidism and mild-to-moderate renal insufficiency

We aimed to assess the efficacy and safety of denosumab in postmenopausal women with primary hyperparathyroidism (PHPT)-related osteoporosis and chronic kidney disease (CKD).

Women over 50 years of age with PHPT or postmenopausal osteoporosis (PMO) were retrospectively recruited into this longitudinal study. These PHPT and PMO groups were further categorized into subgroups based on the presence of CKD (Glomerular filtration rate (GFR) < 60 mL/min/1.73 m²). All patients were given denosumab over 24 months due to verified osteoporosis. The primary outcomes were changes in bone mineral density (BMD) and serum calcium levels.

145 postmenopausal women median age 69 [63;77] were recruited and assigned to one of the subgroups: PHPT patients with CKD (n = 22), PHPT patients without CKD (n = 38), PMO patients with CKD (n = 17) and PMO patients without CKD (n = 68). Denosumab treatment significantly increased BMD in patients with PHPT-related osteoporosis and CKD: median T-score L1-L4 from -2.0 to -1.35 (p < 0.001), femur neck from -2.4 to -2.1 (p = 0.012), radius 33% from -3.2 to -3 (p < 0.05)) at 24 months. Changes in BMD were similar in all four studied groups compared to baseline. A marked decline in calcium was noted in the primary study group of PHPT with CKD (median ΔCa = -0.24 mmol/L p < 0.001), compared to PHPT without CKD (median ΔCa = -0.08 mmol/L p < 0.001) and PMO with or without CKD. Denosumab treatment was well-tolerated with no serious adverse events.

Denosumab treatment was similarly effective at increasing BMD in patients with PHPT and PMO with and without renal insufficiency. The calcium lowering effects of denosumab were most significant in patients with PHPT and CKD. The safety of denosumab did not differ among participants with and without CKD.