Abstract
Thirty two patients with primary hyperparathyroidism were followed up medically for a mean of 4.2 years. One patient had an operation because of a rise in plasma calcium concentration. There was no significant change in the mean plasma calcium and creatinine concentrations or in blood pressure during the period of follow up. The progress of these patients who were managed medically was compared with that of a group of 60 patients who had had successful operations for primary hyperparathyroidism. There was no significant change in mean plasma creatinine concentration or in blood pressure in the group who had had operations during a mean follow up period of 5.9 years. The natural history of mild asymptomatic hyperparathyroidism is probably different from and better than that of the type of hyperparathyroidism that was usually seen before the advent of routine chemical screening. It is suggested that patients over the age of 60 with mild asymptomatic hyperparathyroidism, and perhaps even younger patients, may not require operation.