The NIH criteria for parathyroidectomy in asymptomatic primary hyperparathyroidism: are they too limited?

To determine whether preoperative and postoperative symptoms and outcome differ in patients who meet or fail to meet the NIH criteria for parathyroidectomy.

The NIH Consensus Conference on primary hyperparathyroidism in 1990 defined criteria for surgical intervention suggesting that some patients can be safely managed without surgery.

Over a 3-year period, 202 consecutive patients undergoing parathyroidectomy for primary hyperparathyroidism at a tertiary referral center were prospectively given a questionnaire regarding their symptoms and associated conditions during their initial and follow-up office visits as were 63 thyroid control patients. The 178 patients who completed the follow-up questionnaire were assigned to 2 groups according to the NIH criteria for parathyroidectomy. The frequency of preoperative symptoms and conditions associated with primary hyperparathyroidism as well as postoperative improvement in symptoms and surgical outcome were compared.

Of the 178 parathyroid patients, 103 met the NIH criteria for parathyroidectomy whereas 75 did not. Patient profiles were similar in each group except mean ages, 55 versus 65, and preoperative serum calcium levels, 11.5 mg/dL versus 11.0 mg/dL (NIH and non-NIH groups, respectively; P < 0.001). The incidence of preoperative nonspecific somatic and neuropsychiatric symptoms and associated conditions was equivalent in both groups and more common than in the 63 thyroid control patients. After parathyroidectomy, symptomatic improvement was dramatic and equal between the 2 parathyroid groups. Postoperative mean serum calcium levels were similar (8.78 mg/dL, NIH group, versus 8.75 mg/dL, non-NIH group).

Symptoms were more common in patients with primary hyperparathyroidism versus thyroid controls, but were not different between those patients who met the NIH criteria for parathyroidectomy and those who did not. Patients in both parathyroid groups benefited symptomatically after successful parathyroidectomy.