Impact of Therapy Initiation with Amlodipine or Losartan on Hemodynamic Endpoints and JNC-VI Blood Pressure Stage

Abstract

The relative efficacy of long-acting calcium channel antagonists and angiotensin II receptor blocking agents has been described in clinical trials; however, their effectiveness in an actual practice setting has not been well studied. This study assessed the effectiveness of 2 commonly prescribed antihypertensives, amlodipine and losartan, either as monotherapy or as add-on for patients insufficiently controlled on beta-blocker or diuretic therapy. This was a retrospective, observational study that utilized electronic medical records. Hypertensive patients more than 40 years old who were new users of amlodipine or losartan were included in the study. Patients with congestive heart failure or those using antihypertensives other than diuretics or beta-blockers were excluded. Blood pressure (BP) readings were followed up to 6 months after enrollment. Univariate and multivariate regression models were used to assess the impact of amlodipine or losartan therapy on hemodynamic end points and on JNC-VI BP stage. A total of 346 patients met the entry criteria. Of these, 275 (79.5%) amlodipine and 71 (20.5%) were prescribed losartan. Mean changes in systolic and diastolic blood pressure were greater for patients receiving amlodipine in univariate and multivariate analyses (reduction of 20/8 and 11/4 mm Hg, respectively; P<0.05). Mean change in pulse pressure trended strongly in favor of amlodipine (11.8 mm Hg vs. 7 mm Hg, P = 0.08). Univariate analysis indicated that amlodipine-treated patients were more likely to move to a better JNC-VI BP stage, where as losartan-treated patients, on average, moved to a worse stage. Amlodipine therapy was superior to losartan therapy among this population of hypertensive patients.