Relationships between Blood Pressure and Plasma Renin, Aldosterone and Dopamine-β-Hydroxylase in the Elderly

Abstract
Plasma renin activity (PRA), aldosterone (PA) and dopamine-.beta.-hydroxylase activity (DBH) were measured in 49 subjects > 70 yr of age, selected for normal or high blood pressure level. By comparison to younger controls, elderly subjects exhibited lower supine or upright PRA but similar PA and DBH. No relationship was found between individual blood pressure, and PRA, PA or DBH. Apparently the renin-angiotensin-aldosterone system does not play an important causative role in elderly hypertension. Age-matched controls are necessary when this system is studied in elderly patients.