Dissociation of plasma renin activity and aldosterone in essential hypertension.

Plasma renin activity (PRA) and plasma aldosterone (PA) were measured in 401 and 98 patients, respectively, with mild essential hypertension after overnight recumbency and on a 135 mmol/day sodium diet. The mean PRA values declined with each increasing decade of age, whereas the mean PA concentrations did not, and those PRA and PA values determined simultaneously were not correlated, suggesting that PA concentrations are inappropriately elevated relative to the PRA in patients with essential hypertension in the older decades of age.