Neuropsychologic deficits associated with primary hyperparathyroidism.

Although neuropsychologic dysfunction has been recognized as a symptom of primary hyperparathyroidism since the earliest descriptions of the disease, the nature of the memory, learning, and cognition deficits has been poorly defined. To assess the nature and extent of the deficits, 10 patients with hyperparathyroidism without specific neuropsychologic complaints and 10 normocalcemic patients were tested with a battery of psychologic tests before and after operation. Postoperative test scores for the Wechsler Logical Memory and Associate Learning, Wechsler Memory Digit Span, and the Similarities subtest of the Wechsler Adult Intelligence Scales, which test short-term verbal memory and cognition, showed statistically significant improvement for the patients with hyperparathyroidism. The patients with hyperparathyroidism improved on the Wechsler Memory Quotient an average of 17%. Tests measuring conceptual tracking, short-term visual memory, graphic skills, and fine motor coordination were unchanged. The results suggest that dominant hemispheric functions are disrupted by hyperparathyroidism. Improved neuropsychologic function can be expected after parathyroidectomy and, since the deficit is difficult to assess before operation, may be an indication for operation in the patient without symptoms.