The multiple factors affecting plasma renin activity in essential hypertension.

Seventy-nine patients with essential hypertension were evaluated for peripheral renin activity in response to injection of 60 mg of furosemide and to upright posture. Age and supine diastolic blood pressure were found to be significant determinants of responsiveness, with contributions from sex and race. Patients with impaired responsiveness were predominantly older and female, while the group of hyperresponders was younger, male, and had significantly lower supine diastolic pressures. Aldosterone responses in relation to changes in peripheral renin activity were found to be nearly random with both furosemide and with posture. Thus, patients could be subdivided into renin subgroups, but not into parallel aldosterone subgroups. Data on four patients with primary hyperaldosteronism were discussed for comparison.