What are the next steps for an 85-year-old female with primary hypothyroidism, chronic kidney disease (CKD), and significantly elevated parathyroid hormone (PTH) levels, who declines surgery and has normal calcium levels?

From the Guidelines

For an 85-year-old female with primary hypothyroidism, CKD, normal calcium, and significantly elevated PTH (717), the next steps should focus on managing secondary hyperparathyroidism due to her CKD, and the current recommendation is to treat patients with PTH values that are progressively increasing or persistently above the upper limit of normal, without routine use of calcitriol or vitamin D analogues due to the increased risk for hypercalcemia, as suggested by the Kidney Disease: Improving Global Outcomes 2017 clinical practice guideline update 1.

Key Considerations

• The patient's significantly elevated PTH level (717) indicates secondary hyperparathyroidism, a common complication of CKD.
• The normal calcium level suggests that the patient is not currently at risk for hypercalcemia, but this will need to be monitored closely with any treatment.
• The patient's wish to avoid surgery is reasonable, given the potential risks and the fact that this is likely secondary hyperparathyroidism.

Treatment Approach

• Start with calcitriol (active vitamin D) at 0.25 mcg daily, which can be titrated up to 0.5 mcg daily based on response, as this is a common treatment approach for secondary hyperparathyroidism in CKD patients, although it should be used with caution due to the risk of hypercalcemia 1.
• Ensure adequate vitamin D supplementation with cholecalciferol 1000-2000 IU daily to maintain 25-OH vitamin D levels above 30 ng/mL.
• Monitor calcium, phosphorus, and PTH levels every 3 months initially.
• Consider adding a phosphate binder such as calcium acetate if hyperphosphatemia develops.

Coordination of Care

• Continue coordination with nephrology for ongoing management of both CKD and mineral bone disorder.
• Regularly review the patient's treatment plan and adjust as needed to minimize the risk of complications and optimize outcomes.

Evidence-Based Decision Making

• The treatment approach is based on the most recent and highest quality study available, which is the Kidney Disease: Improving Global Outcomes 2017 clinical practice guideline update 1.
• The use of calcimimetics, such as cinacalcet, may not be warranted in this patient, as the evidence suggests that it provides small reductions in the risk of surgical parathyroidectomy but has little or no effect on all-cause mortality and uncertain effects on cardiovascular death for people with CKD 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Cinacalcet tablets should be taken with food or shortly after a meal (2.1) Secondary HPT in patients with CKD on dialysis (2. 2): Starting dose is 30 mg once daily. Titrate dose no more frequently than every 2 to 4 weeks through sequential doses of 30,60,90,120, and 180 mg once daily as necessary to achieve targeted intact parathyroid hormone (iPTH) levels.

The patient has primary hypothyroidism and significantly elevated PTH with normal calcium levels. The drug label provides dosing information for secondary HPT in patients with CKD on dialysis and hypercalcemia in patients with primary HPT.

• The patient's condition is primary HPT, but the label does not provide a specific dosing recommendation for primary HPT with normal calcium levels.
• However, the label does provide a dosing recommendation for hypercalcemia in patients with primary HPT, starting with 30 mg twice daily.
• Given the patient's elevated PTH and normal calcium levels, it is unclear if the dosing recommendation for hypercalcemia in primary HPT is applicable.
• Therefore, cinacalcet may be considered, but the dosing should be individualized and monitored closely, with regular monitoring of serum calcium and PTH levels 2.
• It is also important to consider the patient's CKD and nephrology follow-up when making treatment decisions.

From the Research

Patient Profile

• 85-year-old female with primary hypothyroidism
• Does not want to undergo surgery
• Has chronic kidney disease (CKD) and is being followed by Nephrology
• Significantly elevated parathyroid hormone (PTH) level of 717
• Normal calcium levels

Relevant Studies

• A study published in 2013 3 found that treatment with cinacalcet improves the control of secondary hyperparathyroidism (SHPT) and the achievement of calcium and phosphorus targets in patients with CKD.
• Another study published in 2016 4 found that cinacalcet is effective in patients with CKD and SHPT not receiving dialysis, with a significant reduction in PTH levels.
• A meta-analysis published in 2019 5 found that the combination of cinacalcet and vitamin D is effective in lowering serum calcium, phosphorus, and calcium-phosphorus product in patients with SHPT undergoing dialysis.
• A study published in 2021 6 discussed the diagnosis and management of normocalcemic primary hyperparathyroidism (NPHPT), which is characterized by elevated PTH levels with normal calcium levels.
• A review published in 2023 7 discussed the distinction between SHPT and NPHPT, as well as the end-organ effects of NPHPT and outcomes of surgery in NPHPT.

Potential Next Steps

• Consider treatment with cinacalcet to reduce PTH levels, as suggested by studies 3 and 4.
• Monitor calcium and phosphorus levels closely, as cinacalcet can increase the risk of hypocalcemia, as noted in study 5.
• Consider the diagnosis of NPHPT, as discussed in studies 6 and 7, and exclude secondary causes of elevated PTH levels.
• Discuss the potential benefits and risks of surgery with the patient, as suggested by study 7.