Blood pressure in subjects with hypercalcaemia and primary hyperparathyroidism detected in a health screening programme.

Primary hyperparathyroidism was the most likely diagnosis in sixty-eight non-thiazide treated patients with hypercalcaemia detected in a health screening. The group included fifty-five females and thirteen males with a mean +/- SEM age of 55.0 +/- 0.7 years. On a pair basis, these patients were compared with a series of sixty-eight age- and sex-matched normocalcaemic subjects selected from the health screening register. Five subjects in each group were receiving medication for hypertension. Systolic and diastolic blood pressures were significantly higher in the hypercalcaemic subjects in the remaining fifty-eight pairs (P less than 0.001). This difference was unrelated to impaired renal filtration and many other factors associated with hypertension. It is concluded that hypercalcaemia and/or other effects of deranged parathyroid function per se may result in a blood pressure elevation on which need not necessarily attain the level of hypertension.