Beta blocker drugs are commonly used in the initial attempts to lower blood pressure. However a Cochrane Review shows that they were not as good at reducing death or the severity of disease as other classes of drugs. Drugs that perform better include thiazides, calcium channel blockers and renin angiotensin system inhibitors.

Starting with the best therapy is important because even a modest reduction of blood pressure in people with hypertension can significantly reduce their risk of suffering from stroke or cardiovascular disease.

The Cochrane Review gathered data from 13 different randomized controlled trials that together involved over 91,000 participants. The effect of beta blockers was not significantly different from placebo in terms of total mortality or coronary heart disease. Beta blockers did, however, reduce the risk of stroke by 0.5% when compared to placebo, but in trials that compared beta blockers with calcium channel blockers (CCB), patients on CCB drugs had fewer strokes.

"The available evidence does not support the use of beta blockers as first-line drugs in the treatment of hypertension. This conclusion is based on the relatively weak effect of beta-blockers to reduce stroke and the absence of an effect on coronary heart disease when compared to placebo or no treatment," says Lead Review Author Charles Shey Wiysonge, who works at the Ministry of Public Health, in Yaoundé, Cameroon.

The beta blocker given to 75% of these participants was atenolol, and more research is needed to determine whether different beta blockers have different effects.

Wiysonge CS et al. Volmink J. Beta-blockers for hypertension. Cochrane Database of Systematic Reviews 2007, Issue 1. Art. No.: CD002003. DOI: 10.1002/14651858.CD002003.pub2.

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The Cochrane Library, 2007, Issue 1

Notes

1. The Cochrane Library contains high quality health care information, including Systematic Reviews from The Cochrane Collaboration. These Reviews bring together research on the effects of health care and are considered the gold standard for determining the relative effectiveness of different interventions. The Cochrane Collaboration (http://www.cochrane.org/) is a UK registered international charity and the world's leading producer of systematic Reviews. It has been demonstrated that Cochrane Systematic Reviews are of comparable or better quality and are updated more often than the Reviews published in print journalsª.

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The US State of Wyoming http://wyld.state.wy.us/dbloginform.html/ All residents can access The Cochrane Library for free at the state's Wyoming Libraries Database libraries which include public, community college and medical libraries thanks to funding provided by Wyoming State Legislature's Joint Labor, Health and Social Services Committee

4. There are also several programmes, such as the Health InterNetwork Access to Research Initiative (HINARI) that provide access in developing countries. To find out whether your country is included in any of these programmes/provisions, or to learn how to get access if you don't already have it, please visit: http://www.thecochranelibrary.com/.

ª Jadad AR, Cook DJ, Jones A, Klassen TP, Tugwell P, Moher M, et al. Methodology and reports of systematic Reviews and meta-analysies: a comparison of Cochrane Reviews with articles published in paper-based journal.

Contact: Amy Molnar
John Wiley & Sons, Inc.