Vitamin D Repletion in Primary Hyperparathyroidism

Columbia University

Status and phase

Completed

Phase 4

Conditions

Primary Hyperparathyroidism

Vitamin D Deficiency

Treatments

Drug: 10,000 IU Vitamin D3

Dietary Supplement: Vitamin D

Other: Placebo

Study type

Interventional

Funder types

Other

NIH

Identifiers

NCT01306656

AAAF1797

R01DK084986-05 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

This study will look at the effect of 2 treatment regimens that contain vitamin D in a six-month treatment trial of patients with PHPT who are vitamin D deficient. Patients will be assigned randomly to one of 2 regimens, and will be followed with tests of their blood, urine and bones. This study should provide important information on the effect of vitamin D therapy in patients with PHPT. In addition, data from this study will guide physicians as to how best to treat their patients who have PHPT and vitamin D deficiency.

Full description

Primary hyperparathyroidism (PHPT) is a common disease in which the parathyroid glands produce excessive amounts of parathyroid hormone (PTH), which regulates calcium levels. In primary hyperparathyroidism, high levels of PTH remove too much calcium from bones and deposit the excess calcium in the blood, which is then filtered into the urine by the kidneys. Bone health is threatened by the excess calcium loss which weakens the structure of the bones.

Many patients with primary hyperparathyroidism also have low vitamin D (25OHD) levels which is thought to further impair bone health. Recent medical guidelines recommend treating patients with primary hyperparathyroidism who have low vitamin D levels with oral vitamin D but the optimal vitamin D dose and rate of repletion is unclear. It is, therefore, important to determine if replenishing Vitamin D will improve bone health in primary hyperparathyroidism, and if so, to assess the impact of the rate of vitamin D repletion.

Enrollment

9 patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Diagnosed PHPT, defined by an elevated serum calcium level (we will not study normocalcemic PHPT) with elevated or inappropriately normal PTH levels.
Vitamin D3 less than 30 ng/ml

Exclusion criteria

Patients with familial hyperparathyroid syndromes
Current or past use of the following medications: bisphosphonate within past 2 years, use of lithium or thiazide diuretics, current use of cinacalcet, use of aluminum containing medications, cimetidine, colestipol, or orlistat
Malignancy, except cured basal or squamous cell skin carcinoma or other cured cancers that are at least five years free from recurrence
History or current diagnosis of certain medical diseases (including sarcoidosis, active infectious granulomatous disease, HIV/AIDS, chronic kidney disease (serum creatinine > 1.5 mg/dL), liver disease; GI diseases known to affect calcium metabolism; secondary hyperparathyroidism);
We will also exclude patients with calcium above 11.5 mg/dL, urine calcium above 350 mg/day, and active nephrolithiasis because vitamin D repletion could potentially exacerbate hypercalcemia or hypercalciuria
Other exclusions include protected individuals (institutionalized), prisoners, and any other prospective participant who might not be able to give voluntary informed consent.