Hypertension treatment and implications of recent cardiovascular outcome trials

Clinical trials have shown that effective control of blood pressure reduces the risk of cardiovascular events in high-risk patients. For example, data from the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) study show significant reductions in the incidence of cardiac events, stroke and all-cause mortality in patients in whom blood pressure control was achieved compared with those in whom blood pressure remained uncontrolled. Although the Antihypertensive and Lipid-Lowering treatment to prevent Heart Attack Trial (ALLHAT) demonstrated no significant difference in cardiovascular mortality and morbidity between patients receiving diuretics, calcium channel blockers or angiotensin-converting enzyme (ACE) inhibitors, this finding might have been confounded by differences in the blood pressure reductions achieved with the three treatments. Other studies have consistently shown that newer antihypertensive agents, such as ACE inhibitors and calcium channel blockers, reduce cardiovascular events to a similar, or possibly greater, extent as older therapies, such as diuretics and beta-blockers. In particular, ACE inhibitors appear to offer additional benefits beyond blood pressure reduction in terms of reducing cardiovascular events and producing renoprotective effects. Angiotensin II receptor blockers (ARBs) have been less extensively studied, but there is evidence already that they have heart failure, stroke and renoprotective benefits. The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) is currently comparing the effects of the ARB telmisartan 80 mg and the ACE inhibitor ramipril 10 mg, alone and in combination, on cardiovascular events in high-risk patients.