The effect of surgical management in mitigating fragility fracture risk among individuals with primary hyperparathyroidism

Background: Primary hyperparathyroidism predominately affects women who are postmenopausal and causes complications, including fragility fractures. Its treatment is parathyroidectomy, which is associated with low complication and >95% cure rates. Considering fractures are associated with premature death, we aimed to determine whether the surgical management of individuals with biochemical diagnosis of primary hyperparathyroidism was associated with a reduction in fracture risk.

Methods: In this population-based cohort study, we used administrative health databases to identify adults ≥18 year old who were biochemically diagnosed with primary hyperparathyroidism between 2007 and 2016 in Ontario. Patients were included if their calcium was ≥2.6 mmol/L (≥10.42 mg/dL) with a concurrent parathyroid hormone of ≥2.2 pmol/L (≥20.75 pg/mL). We followed patients and compared the incidence of fractures between those with and without parathyroidectomy. To control for potential confounding, we used inverse probability of treatment weighting to estimate the average treatment effect in the treated. Fine-Gray competing risk regression models were used to determine the association between surgery and time to fracture.

Results: In a cohort of 28,059 with a biochemical diagnosis of primary hyperparathyroidism, the mean age (standard deviation) was 65 years (14.2 years), and 75% (n = 21,139) were female. Only 12.6% (n = 3,523) underwent parathyroidectomy. Weighted fracture cumulative incidence at 12 years postdiagnosis was 10.17% (n = 182) in surgical patients and 14.04% (n = 2,004) in nonsurgical patients. Parathyroidectomy prevented 1 fracture for every 26 surgeries performed (weighted risk difference, 3.87%, 95% confidence interval, 0.96%-6.62%) and reduced the hazard of fracture by 22% (weighted hazard ratio, 0.78; 95% confidence interval, 0.64-0.95).

Conclusion: In a large, publicly funded health system, parathyroidectomy significantly reduced the short- and long-term risk of fragility fractures in patients with primary hyperparathyroidism.