What is the management approach for high parathyroid hormone (PTH) levels?

From the Guidelines

The management of high parathyroid hormone (PTH) levels typically requires surgical removal of the affected parathyroid gland(s) for primary hyperparathyroidism, with parathyroidectomy being the definitive treatment for symptomatic patients or those meeting surgical criteria. The approach to managing high PTH levels depends on the underlying cause, with primary hyperparathyroidism being the most common form, usually due to a single parathyroid adenoma 1. For patients with primary hyperparathyroidism who are asymptomatic but meet surgical criteria, or for those who are symptomatic, parathyroidectomy is recommended as it can prevent long-term complications associated with hypercalcemia, such as bone disease, kidney stones, and cardiovascular issues 1.

Surgical Management

There are two accepted curative operative strategies for primary hyperparathyroidism: bilateral neck exploration (BNE) and minimally invasive parathyroidectomy (MIP) 1. BNE involves a bilateral operation where all parathyroid glands are identified and examined, with the diseased glands being resected. MIP, on the other hand, is a unilateral operation that utilizes limited dissection for targeted removal of the affected gland, requiring confident preoperative localization of a single parathyroid adenoma and intraoperative PTH monitoring to confirm removal of the hyperfunctioning gland 1.

Medical Management

For patients who cannot undergo surgery, medical management may include cinacalcet to lower PTH levels, and bisphosphonates to manage bone loss. In cases of secondary hyperparathyroidism associated with chronic kidney disease, treatment focuses on correcting underlying abnormalities with phosphate binders, vitamin D analogs, and calcimimetics like cinacalcet 1. Adequate calcium intake and vitamin D supplementation are crucial for all patients, alongside regular monitoring of calcium, phosphorus, and PTH levels to guide therapy adjustments.

Considerations for Secondary Hyperparathyroidism

In chronic kidney disease, secondary hyperparathyroidism is a common complication that may require surgical intervention if medical therapy fails to control the condition. The choice of surgical approach, including subtotal parathyroidectomy, total parathyroidectomy, or total parathyroidectomy with autotransplantation, depends on various factors, including the severity of the disease and the surgeon's preference 1. Recent studies suggest that total parathyroidectomy may have advantages over other methods in reducing the recurrence of secondary hyperparathyroidism, although the decision should be individualized based on patient factors and surgical expertise.

Quality of Life and Morbidity Considerations

The goal of managing high PTH levels is to improve quality of life by preventing complications associated with hyperparathyroidism, such as bone disease, kidney stones, and cardiovascular morbidity. Surgical intervention, when appropriate, can significantly improve outcomes for patients with primary hyperparathyroidism. For those with secondary hyperparathyroidism, a multidisciplinary approach that includes medical and surgical management can help mitigate the morbidity associated with chronic kidney disease and its complications. Regular follow-up and monitoring are essential to adjust treatment strategies as needed and to minimize the risk of long-term complications.

From the FDA Drug Label

Paricalcitol capsules are indicated in adults and pediatric patients 10 years of age and older for the prevention and treatment of secondary hyperparathyroidism associated with Chronic Kidney Disease (CKD) Stages 3 and 4.

Initial Dose Table 1 Recommended Paricalcitol Capsules Starting Dose Based upon Baseline iPTH Level

• To be administered not more often than every other day Baseline iPTH Level Daily Dose Three Times a Week Dose* Less than or equal to 500 pg/mL 1 mcg 2 mcg More than 500 pg/mL 2 mcg 4 mcg

The management approach for high parathyroid hormone (PTH) levels involves the use of paricalcitol capsules to prevent and treat secondary hyperparathyroidism associated with Chronic Kidney Disease (CKD). The initial dose of paricalcitol capsules is based on the baseline iPTH level, with a recommended starting dose of 1 mcg daily or 2 mcg three times a week for iPTH levels less than or equal to 500 pg/mL, and 2 mcg daily or 4 mcg three times a week for iPTH levels more than 500 pg/mL. Dose titration is then individualized based on iPTH, serum calcium, and phosphorus levels to maintain an iPTH level within target range 2.

Key points:

• Paricalcitol capsules are used to prevent and treat secondary hyperparathyroidism in CKD patients.
• Initial dose is based on baseline iPTH level.
• Dose titration is individualized based on iPTH, serum calcium, and phosphorus levels.
• Monitoring of serum calcium and phosphorus levels is crucial to minimize the risk of hypercalcemia 2.

From the Research

Management Approach for High Parathyroid Hormone (PTH) Levels

The management of high PTH levels depends on the underlying cause, which can be primary or secondary hyperparathyroidism.

• Primary Hyperparathyroidism: In cases of primary hyperparathyroidism, the definitive therapy is parathyroidectomy, which is appropriate to consider in all patients 3. However, for patients who cannot or do not want to undergo surgery, medical management is available. This includes calcium and vitamin D supplementation, with the recommended calcium intake following guidelines established for all individuals 3. Patients with low serum 25-hydroxyvitamin D should be repleted with doses of vitamin D aiming to bring serum 25-hydroxyvitamin D levels to ≥ 50 nmol/L (20 ng/mL) at a minimum 3.
• Secondary Hyperparathyroidism: For secondary hyperparathyroidism, treatment with vitamin D and calcium is often complicated by hypercalcemia and hyperphosphatemia 4. Calcimimetics, such as cinacalcet, target the calcium-sensing receptor and lower PTH levels without increasing calcium and phosphorus levels 4, 5. Cinacalcet has been shown to effectively reduce PTH levels in patients with chronic kidney disease, both on and off dialysis 4, 5. Other options include paricalcitol capsules, which have been shown to reduce PTH levels without changing calcium and phosphorus levels 6.
• Pharmacological Approaches: Pharmacological approaches, such as cinacalcet and bisphosphonate therapy, are available for the management of high PTH levels 3. Cinacalcet is the treatment of choice for the control of hypercalcemia, and bisphosphonate therapy is recommended to improve bone mineral density (BMD) 3. Combination therapy with both agents may be reasonable, but strong evidence for the efficacy of this approach is lacking 3.