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 Björn Dahlöf, from the Sahlgrenska University Hospital, Östra, 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."
The complete results of the ASCOT trial will be made available when all data up to and including the last individual patient visit have been collected and analysed. Investigators and patients will be informed of the final results of ASCOT when these data become available. The results will be published in the scientific press.
Of over 19,000 patients randomised to the two different blood pressure strategies, approximately 10,000 patients were also randomised to treatment with either atorvastatin or placebo in the ASCOT Lipid Lowering Arm (ASCOT-LLA). The ASCOT-LLA was stopped prematurely in October 2002, as a result of substantial benefits associated with statin use in the prevention of heart attacks and strokes.
The principal sponsor of ASCOT is Pfizer Inc, New York. Support has also been provided by Servier Research Group, Paris and Leo Laboratories, Copenhagen.
Launched in 1997, the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) is an independent, investigator-led study aiming to evaluate different treatment strategies to prevent cardiovascular disease in hypertensive patients.
It is being conducted in over 650 general practices or in 32 regional medical centres across the UK, Ireland and the five Nordic countries, Sweden, Finland, Denmark, Norway and Iceland.
Number of patients on the ASCOT trial by country
Denmark (including Iceland) -- 1,567
Finland -- 2,382
UK and Ireland 9,098
With over 19,000 patients across the UK, Ireland and Scandinavia, ASCOT is the largest European based prospective, randomised hypertension trial ever to be conducted.
It is jointly coordinated by Imperial College London (International Centre for Circulatory Health, National Heart and Lung Institute at St Marys Hospital, London) and Scandinavian Coordinating Centre (Scandinavian CRI AB), Göteborg, Sweden.
ASCOT web site: www.ascotstudy.org