Health Care Utilization in Patients with Primary Hyperparathyroidism

PRINCIPAL INVESTIGATOR: Shaghayegh Aliabadi, MD
CO-INVESTIGATOR: Chet Hammill, MD

Background Information
Hyperparathyroidism is the most common pathologic condition affecting the parathyroid glands. This disorder, which is often caused by a noncancerous tumor in a single parathyroid gland results in inappropriate hypersecretion of parathyroid hormone. This in turn leads to persistent elevation of serum calcium level and the inherent consequences of chronic hypercalcemia. Surgical treatment is the only curative therapy and has been the standard of care for patients with overt “symptoms”, mainly kidney stones and fractures.

Treatment of “asymptomatic” patients with mild hypercalcemia, however, has been controversial. While some consider this condition as a fairly benign entity that can be indefinitely observed; others call for a more aggressive approach. The current National Institute of Health consensus statement released in 2008 recommends observation with long-term follow up in “asymptomatic” patients, with operative intervention reserved for young patients under the age of 50, those with marked elevation of serum calcium, overt osteoperosis or renal function deterioration. (1)

These recommendations, because of the exclusion of many symptoms associated with this disease process, have been viewed by some experts as too narrow. (2) It has been demonstrated that patients with this condition have a higher risk of glucose intolerance, overt diabetes, cardiac as well as cerebrovascular disease and even premature death.(3-6) In addition hyperparathyroid patients can suffer from a multitude of vague psychosomatic symptoms such as fatigue, depression, weakness, sleep disturbance and consequently a diminished quality of life.(7-9)

Beyond clinical concerns, the cost considerations associated with indefinite medical observation or non-treatment of patients with hyperparathyroidism has been raised. The contribution of this disease process to the onset or worsening of certain chronic illnesses may potentially result in increased health care utilization. Up to now, cost analysis models have demonstrated cost effectiveness of surgical treatment compared to observation in asymptomatic patient with a life expectancy of more than 5 years. This observation has held true with bilateral neck exploration and even more so with the less invasive, focused parathyroidectomy. (10-12) Confirmation of these cost benefits, by directly examining the cost of health care delivery, in the clinical setting would be of interest and value.

Hypothesis
Patients with primary hyperparathyroidism have a higher utilization of health care resources than those without this diagnosis.

Study Details
The purpose of the study is to retrospectively compare utilization of healthcare resources of hyperparathyroid patients within a large health plan to age and gender matched members without this disease. Secondary endpoints include examining the type of most frequently used services and variables such as patient demographics, duration of hypercalcemia and degree of PTH abnormality that may contribute to the cost of care delivery. Records of Providence Health Plan from 1/2007 through 12/2008 will be queried to identify patients with a known diagnosis of primary hyperparathyroidism. The data in patients with primary hyperparathyroidism will be collected and compared to age and gender matched health plan members without primary hyperparathyroidism. For the subgroup of patients who have a Providence Medical Group primary care provider, the PMG quality/outcome database will be queried for clinical data including demographics, laboratory studies and the types of services generating cost. The data from the Providence Health Plan and from PMG will be presented to the investigators in a de-identified manner.