Abstract 20076: Effect of Combination Therapy with Benazepril/Amlodipine Compared with Benazepril/Hydrochlorothiazide in Patients with High-Risk, Stage 2 Hypertension with or Without Known Coronary Artery Disease
Combination therapy with benazepril 40 mg/amlodipine 10 mg (B+A) has been shown to be more effective than benazepril 40 mg/HCTZ 25 mg (B+H) in reducing cardiovascular (CV) events in high risk patients (pts) with stage 2 hypertension (HTN) at equivalent blood pressure (BP) reduction. While patients with angina or recent CV events were excluded from the study the known effectiveness of amlodipine in pts with coronary artery disease (CAD) prospectively raised the question as to whether B+A would be more effective than B+H in reducing CV events in pts without known CAD (non CAD) at baseline. At baseline there were significant differences between the 5314 CAD and the 6191 non CAD pts. CAD pts had lower SBP and pulse, less stroke and diabetes, more dyslipidemia and more on lipid-lowering agents, beta-blockers and anti-platelets. However, there were no differences at baseline between B+A and B+H in either the CAD or non CAD pts. In pts with CAD the mean BP for B+A and B+H was 143.9 and 144.2 mmHg (146.5 and 146.4 mmHg for non CAD pts), respectively, at baseline and 130.4 and 131.1 mmHg (132.5 and 133.1 mmHg for non CAD pts), respectively, after 24 months follow up. CAD pts had a higher CV event rate than non CAD pts, 14.6% vs. 7.3%, p< 0.0001. In CAD pts there was a 20% reduction in hazard ratio (HR) for CV events (primary endpoint) with B+A vs. B+H, p=0.0016, while in non CAD pts the reduction in HR for B+A was 19%, p= 0.0260. In a prespecified secondary analysis of the composite endpoint including only CV death, MI, and stroke the reduction in HR in CAD pts for B+A vs B+H was 27%, p= 0.0033 and in non CAD pts 14%, p= 0.1896 (p interaction NS). Thus, B+A is more effective than B+H at equivalent BP reduction in reducing CV events in high risk stage 2 HTN in both non CAD and CAD pts, with significant HR reduction of 20% and 19%, respectively. The effectiveness of B+A in non CAD pts may in part be attributable to the presence of occult CAD at baseline and/or the effect of B+A to impede the accelerated progression of atherosclerosis in pts with HTN and thus the occurrence of CV events. Thus the specific CV benefit of B+A over B+H was present in both CAD and non CAD suggests that the combination of an ACE-I + dihydropyridine calcium channel blocker should be preferentially used in pts with high risk stage 2 essential HTN.
- © 2010 by American Heart Association, Inc.