The 'first look' at the data also found that those on the new treatment strategy had a one third less chance of developing diabetes compared with the older strategy.
The 19,000 patient Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) had been comparing a new treatment strategy for hypertension, or high blood pressure, against an old one, in order to discover which is better at preventing various cardiovascular events such as heart attacks and strokes.
In November 2004, the trial was stopped after the Steering Committee of ASCOT accepted the recommendation of its Data Safety Monitoring Board that the blood pressure arm of the trial should be stopped, due to far better results for those patients on the new treatment.
The newer treatment strategy using the calcium channel blocker, amlodipine, and the angiotensin converting enzyme inhibitor, perindopril was compared with the older treatment strategy based on the beta-blocker, atenolol and the thiazide diuretic, bendroflumethiazide.
ASCOT study co-chairmen Peter Sever from Imperial College London, UK, and Bjrn Dahlf, from the Sahlgrenska University Hospital, stra, Sweden, comment: "Although these are only preliminary results, we are confident the overall results will follow the trend we have seen so far. A reduction of 25 percent in strokes and 15 percent in the incidence of coronary events can make a huge difference to high blood pressure sufferers. Blood pressure is the commonest risk factor contributing to the global burden of disease, and with a projected 1.5 billion sufferers of hypertension by 2020 it is vital that we develop more effective treatments."