All antihypertensive regimens are ‘equal’

Lowering blood pressure (BP), rather than choice of antihypertensive agent per se, is the key to preventing cardiovascular (CV) events, experts claim this week in The Lancet.

“Our results show that treatment with any commonly used regimen reduces the risk of total major CV events, and that larger reductions in BP produce larger reductions in risk,” write Fiona Turnbull (University of Sydney, Australia) and coauthors. The Blood Pressure Lowering Treatment Trialists’ Collaboration, which includes specialists from across the globe, sought to quantify the impact of different antihypertensive drug classes and different BP goals on the risk of major CV events and death. Twenty-nine randomized controlled clinical trials, involving a total of 162,341 patients, met their inclusion criteria. All trials had at least 1000 patient-years of follow-up, and their primary results were reported between July 1995 and June 2003. Among the placebo-controlled trials, regimens based on either ACE inhibitors or calcium antagonists reduced the relative risks of total major CV events by 22% and 18%, respectively. Angiotensin II type 1 antagonist (ARB)-based regimens reduced major CV events by 10%, as did strategies targeting lower BP goals (15%). “There were no significant differences between regimens based on ACE inhibitors, calcium antagonists, or diuretics or beta-blockers, although ACE-inhibitor-based regimens reduced blood pressure less,” the authors comment. They did, however, uncover differences between active regimens in their effects on cause-specific outcomes. For example, regimens based on ACE inhibitors, diuretics, or beta-blockers were much more effective in preventing heart failure than were regimens based on calcium antagonists. The team also found a greater effect of ARB-based regimens than other active regimens on the risk of heart failure. “Although some of these differences seem to be largely explained by differences in achieved BPs, others seem to be independent of such differences,” the team comments. In contrast with earlier analyses, the present study found no trend toward a lesser effect of calcium antagonists on coronary heart disease as compared with ACE inhibitors, diuretics, or beta-blockers. “Narrow confidence intervals excluded all but a trivial difference in risk, thereby confirming conclusions from earlier reports, questioning the validity of claims of large increases in coronary heart risk in hypertension patients treated with calcium antagonists,” the authors note.(Source: www.incirculation.net)