Preliminary report: functional MRI of the brain may be the ideal tool for evaluating neuropsychologic and sleep complaints of patients with primary hyperparathyroidism.

BACKGROUND: The incidence, pattern, and severity of sleep disturbance and cognitive dysfunction has not been well characterized for patients with primary hyperparathyroidism (PHPT). There is no agreement on the mechanism of the development or resolution of such symptoms, and in no previous study has cerebral activity been functionally assessed and change documented following surgical cure of patients with PHPT. METHODS: We undertook a prospective analysis to obtain pilot data on 6 patients with PHPT. Functional magnetic resonance imaging (fMRI), formal neuropsychologic (NP) tests, and health-related quality of life (HRQL) measures that included sleep assessments were performed on patients before and after parathyroidectomy. Changes in cortical activation under both conflict and neutral conditions (distracting tasks) were recorded. RESULTS: Functional MRI demonstrated postoperative changes in medial prefrontal cortex activity during cognitive processing of conflict and nonconflict tasks. Further postoperative changes were noted in the dorsolateral prefrontal cortex and parietal cortex with shifts in activations. In addition to the fMRI findings, the patients demonstrated improvements in sleep and social behavior. They tended to experience less fatigue and their processing speed on cognitive tests improved. CONCLUSIONS: These data support the feasibility and willingness of patients with PHPT to undergo fMRI assessment. Preliminary findings reflected a generalized improvement in processing efficiency postoperatively compared with a patient's preoperative state, and the HRQL measures showed improved sleep. These findings mirror those expected with sleep dysfunction. Longitudinal assessment with advanced brain imaging technology, neuropsychological (NP), and sleep evaluations is warranted to further explore cognitive, sleep, and HRQL improvement after parathyroidectomy.

Primary hyperparathyroidism, cognition, and health-related quality of life.

OBJECTIVE: To provide a rigorous and critical review of studies in which formal neuropsychological (NP) testing and measurement of health-related quality of life (HRQL) were conducted pre- and post-parathyroidectomy for primary hyperparathyroidism (PHPT). These data contribute to the discussion on the utility of surgical intervention for nonclassic PHPT. SUMMARY BACKGROUND DATA: PHPT is a complex endocrinopathy involving calcium metabolism and a potent hormone made by the parathyroid glands. Approximately 1.5% of Americans age 65 years and older, representing more than 3.9 million people, have PHPT, and the prevalence in postmenopausal women is estimated at 3.4%. Current National Institutes of Health guidelines for curative, surgical intervention of PHPT exclude 80% of patients with hyperparathyroid disease who have subjective neurobehavioral and physical symptoms that affect the quality of their lives. METHODS: An electronic search was conducted of prospective studies in which cognitive functioning was measured with formal NP tests and HRQL was measured with valid and reliable instruments before and following parathyroidectomy for PHPT. RESULTS: : In studies conducted pre- and post-parathyroidectomy for PHPT, 6 small studies of cognitive functioning report inconsistent findings; however, 7 well-designed studies of HRQL report improvement across multiple domains following surgery. CONCLUSIONS: Surgical treatment of PHPT is a viable option for patients with laboratory diagnosed, "nonclassic" PHPT. Formal NP testing and evaluation of HRQL are useful tools that may assist physicians in choosing whom to refer for parathyroidectomy. Further longitudinal study of NP functioning and HRQL in patients with laboratory diagnosed PHPT is warranted.