The risks and benefits of initial irbesartan/hydrochlorothiazide combination therapy in patients with severe hypertension.

The impact of delays in blood pressure (BP) reduction is particularly relevant for patients with severe hypertension who are at risk for hypertensive emergencies. Combination therapies may hold promise as initial treatment for these patients. The safety and efficacy of initial irbesartan / hydrochlorothiazide (angiotensin receptor blocker / thiazide) treatment was compared with that of irbesartan as monotherapy in a multicenter, double-blind, parallel-group study in patients with severe hypertension. After 5 weeks, 47% of patients receiving combination therapy achieved a target diastolic BP <90 mm Hg compared with 33% with monotherapy (P=.0005). Similarly, systolic BP/ diastolic BP <140 / 90 mm Hg targets were reached by more subjects treated with combination therapy than subjects receiving monotherapy (34.6% vs 19.2%, P<.0001). Initial use of combination therapy instead of monotherapy is estimated to prevent between 250 and 4500 cardiovascular events in every 100,000 severely hypertensive patients over 5 years, without significantly increasing serious adverse event rates.