Longitudinal studies of mild primary hyperparathyroidism.

In 1969, a health survey was offered to all inhabitants of a town district in Sweden. A clinical examination was carried out, and among other variables, a measurement was made of serum calcium. The same procedure was repeated in 1971. From these two investigations a cohort of 176 individuals (1.1%) with sustained hypercalcemia was identified who could be followed during the subsequent 15 years. Comparisons were made with an age- and sex-matched control group from the same health survey. Survival was significantly lower in the hypercalcemic cohort than in the control group. This reduction was related to the degree of hypercalcemia and apparently mainly due to diseases of the circulatory organs. There was no marked deterioration of renal function, and although there was in some patients a moderate progression of the hypercalcemia, none developed a hypercalcemic crisis during 15 years of follow-up. In consecutively referred patients with primary hyperparathyroidism, psychiatric disturbances of mainly a depressive character were found upon detailed analysis within a majority of the patients, and parathyroid surgery resulted in a clear improvement in mental health.