Hypertension is the most important preventable cause of premature death in developed countries.

In the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT), Bjorn Dahlof of Sahlgrenska University Hospital, Sweden, and colleagues compared outcomes of patients taking older drugs -- atenolol and thiazide -- with those given newer medications, amlodipine and perindopril.

Cardiovascular Disease

The investigators recruited 19,257 patients from 40 to 79 years of age who had a least three other risk factors for cardiovascular events. Half were assigned the atenolol-based regimen and half the amlodipine-based regimen.

After five years, those allocated the amlodipine-based regimen had lower blood pressure values than those on the atenolol -based regimen, the investigators found. In addition, the newer drugs prevented more major cardiovascular events and caused fewer cases of diabetes than the older medications.

"The preferential reduction in cardiovascular events associated with an anti-hypertensive regimen of a calcium-channel blocker (amlodipine) with addition of perindopril, if necessary, particularly when used in combination with effective lipid lowering, results in the prevention of most major cardiovascular events associated with hypertension," says Dr. Dahlof.

"We hope these results will be used to inform clinical practice in ways that should greatly reduce the burden of cardiovascular disease to which patients with hypertension are exposed," he added.

'Cannot Be Rationed'

In a second study, Neil Poulter of the Imperial College London, UK, and colleagues looked at differences in blood pressure and other variables in patients assigned the newer drugs versus those allocated the standard drugs.

A reduction in blood pressure was the single biggest contributor to the effect on stroke events, they found, but other factors -- such as differences in cholesterol -- were more important for coronary events.

"On balance, the ASCOT results endorse the European guidelines for the treatment of hypertension, which leave the responsibility to choose the drug class to initiate anti-hypertensive to the doctor," says Jan Staessen of the University of Leuven, Belgium, in an accompanying commentary.

"ASCOT also supports the use of newer drugs, especially in patients with complicated hypertension, associated risk factors and/or metabolic disturbances," Staessen continues. "Governments and healthcare insurers will have to accept that the use of anti-hypertensive drugs cannot be rationed."