From the Guidelines
Aclasta (zoledronic acid) can be used for osteoporosis in patients with hyperparathyroidism, but requires careful consideration, as recommended by the American College of Physicians guideline update from 2017 1. For patients with primary hyperparathyroidism and osteoporosis, the preferred initial approach is surgical removal of the parathyroid adenoma. If surgery is not possible or osteoporosis persists after surgery, Aclasta may be appropriate as a once-yearly 5mg intravenous infusion. Before administration, hyperparathyroidism should be optimally managed, vitamin D deficiency corrected (aim for levels >50 nmol/L), and adequate calcium intake ensured. Renal function must be assessed, with caution advised if eGFR is below 35 ml/min, as patients with chronic kidney disease (CKD) are at higher risk for bone disease and fractures 1. Patients should be well-hydrated before infusion and may need acetaminophen for post-infusion symptoms like fever and muscle pain that typically occur within the first three days. Aclasta works by inhibiting osteoclast activity, reducing bone resorption that is accelerated in hyperparathyroidism. Regular monitoring of calcium levels is essential as the medication may cause hypocalcemia, particularly in patients with hyperparathyroidism whose calcium metabolism is already disrupted. Key considerations include:
- Optimal management of hyperparathyroidism before Aclasta administration
- Correction of vitamin D deficiency and ensuring adequate calcium intake
- Assessment of renal function and caution with eGFR below 35 ml/min
- Monitoring for post-infusion symptoms and hypocalcemia
- Regular monitoring of calcium levels to prevent hypocalcemia.
From the Research
Aclasta for Osteoporosis in Patients with Hyperparathyroidism
- Aclasta, also known as zoledronic acid, is a bisphosphonate used to treat osteoporosis 2.
- In patients with primary hyperparathyroidism (PHPT) and osteoporosis, parathyroidectomy can improve bone mineral density (BMD) 2.
- Postoperative zoledronic acid treatment can further improve BMD and reduce bone turnover markers in these patients 2.
- However, the use of Aclasta in patients with hyperparathyroidism and osteoporosis requires careful consideration of the patient's calcium and vitamin D levels 3.
- Secondary hyperparathyroidism can occur in patients with primary osteoporosis and osteopenia, and large doses of vitamin D may be necessary to suppress it 3.
Bone Metabolism and Hyperparathyroidism
- Hyperparathyroidism can lead to bone loss and osteoporosis due to increased parathyroid hormone (PTH) levels 4.
- Normocalcemic primary hyperparathyroidism (NPHPT) is a variant of PHPT where serum calcium levels are normal, but PTH is elevated 5.
- Osteoporosis is common in patients with NPHPT, and bone turnover markers may be lower compared to those with hypercalcemic PHPT 5.
- Parathyroidectomy can improve bone metabolism and reduce the risk of fractures in patients with PHPT 5.
Treatment Considerations
- The treatment of osteoporosis in patients with hyperparathyroidism should take into account the patient's PTH levels, calcium and vitamin D levels, and bone turnover markers [(6,3)].
- Aclasta may be a useful treatment option for osteoporosis in these patients, but its use should be carefully monitored to avoid adverse effects on bone metabolism 2.
- Further research is needed to understand the optimal treatment strategies for osteoporosis in patients with hyperparathyroidism 5.