Rapid reduction of severe asymptomatic hypertension. A prospective, controlled trial.

Rapid reduction of severe asymptomatic hypertension with orally administered antihypertensive medication has become a common emergency department practice. To determine if antihypertensive loading prior to initiation of maintenance therapy improved or hastened blood pressure control, 64 asymptomatic patients with severe hypertension were randomized to treatment with (1) hourly doses of clonidine hydrochloride followed by maintenance therapy (group 1); (2) an initial dose of clonidine followed by hourly placebo and subsequent maintenance therapy (group 2); or (3) maintenance therapy without prior loading (group 3). There was no difference between groups 1 and 2 in the time required to achieve acceptable blood pressure control during loading therapy, nor was there a difference at 24 hours in pressure reduction between groups 1,2, or 3. Further follow-up in 44 of these patients at 1 week demonstrated adequate control of systemic blood pressure in all groups, but no difference between groups. In view of the small but reported risk of antihypertensive loading and the burden and expense of prolonged emergency department therapy, these results suggest that the common practice of acute oral antihypertensive loading to treat severe, asymptomatic hypertension should be reconsidered.

Synergistic effect of captopril with hydrochlorothiazide for the treatment of low-renin hypertensive black patients.

Diuretics have been particularly successful for treatment of low-renin hypertension (LRH), although they may cause metabolic complications such as hypokalemia and hyperglycemia. Since the efficacy of diuretics is largely limited by reactive angiotensin II production, a combination of a converting enzyme inhibitor with a diuretic should be synergistic, particularly in LRH, where heightened aldosterone production in response to angiotensin II has been noted. Eighteen patients with LRH were treated initially with either captopril alone (450 mg/day) or hydrochlorothiazide (HCTZ) (up to 100 mg/day). Captopril alone only reduced average placebo standing blood pressure from 151/100 to 146/96 mm Hg. Combination of HCTZ with captopril reduced average standing blood pressure to 111/76 mm Hg at 3 months and 116/81 mm Hg at 1 year while allowing reductions in average captopril dosage to 100 mg/day and HCTZ dosage to 40 mg/day and reductions in supplemental potassium administration and in HCTZ-induced hyperglycemia. Captopril monotherapy did not increase urinary excretion of kallikrein, prostaglandin E2, or 6-keto prostaglandin F1 alpha, a metabolite of prostacyclin, and did not reduce urinary aldosterone excretion chronically. Thus, a synergism of captopril with HCTZ may be advantageous in certain patients with LRH.