The pattern of plasma renin activity and aldosterone secretion was studied in 56 unselected patients with essential hypertension and in 10 hypertensive patients with renal complications. The results were compared to responses found in 17 normal subjects and 6 patients with verified primary aldosteronism. In all cases, plasma renin activity and aldosterone secretion rates were measured under precise conditions of metabolic balance, initially during dietary salt restriction and then after physiologic saline infusions. Abnormally low responses in plasma renin activity to salt restriction were found in 13 patients with essential hypertension (25 percent), and in 4 there was no significant increase with standing. The expected increase in aldosterone secretion also failed to occur in 9 patients, 6 of whom demonstrated low plasma renin activity. The great majority of patients with essential hypertension responded normally to saline infusions with decreased plasma renin activity and aldosterone secretion, but in 4 patients the latter was greater than 300 μg/day after saline infusion. The response of hypertensive patients with renal complications was not different from that seen in uncomplicated cases. Although there was great variation in the responses seen in individual patients with essential hypertension, the combination of suppressed plasma renin activity and autonomous, excessive aldosterone secretion was found in only 1 patient. In this unselected series, the maximal incidence of primary aldosteronism (using the currently accepted criteria) was less than 5 percent.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine