Common Heart Drug May Block Atherosclerosis
April 2, 2001 -- An inexpensive and widely available drug already known to decrease the risk of repeat heart attacks and treat heart failure now appears to slow artery clogging atherosclerosis as well, and thus may be useful to prevent strokes and heart disease altogether.
"This is the first study in man to show that the beta-blocker drug metoprolol slows the progression of signs of atherosclerosis in the carotid artery, [the major pathway of blood to the brain]," study author Göran Berglund, MD, PhD, tells WebMD. "It also hints at the possibility that a very low dose might decrease the risk of heart attack, stroke, and death." Berglund is a professor of medicine at Malmo University Hospital in Lund, Sweden. The study is published in the April 3 issue of Circulation: Journal of the American Heart Association.
In individuals with atherosclerosis, buildup of plaque deposits in the arteries narrows them, and when this happens in the neck's carotid arteries, blood flow to the brain is choked off. Fragments of plaque or blood clot can break off and clog up smaller blood vessels, where they can cause a stroke.
Currently, cholesterol-lowering drugs, such as statins, are the only drugs widely regarded to reduce the rate of atherosclerosis.
Plaque in the carotid arteries is a major public health problem, affecting more than one-third of individuals 51 to 55 years old, and more than half of individuals 61 to 65 years old in a large Swedish population studied by Berglund and colleagues from other Swedish universities.
Berglund's team studied almost 800 individuals who had plaque in the carotid arteries, but were otherwise healthy and had no symptoms of stroke, such as weakness in the limbs or slurred speech.
Study participants were randomly assigned to one of four treatment groups for three years, with neither subjects nor researchers knowing which subjects were taking which medications until the study was over.
One group took fluvastatin, a cholesterol-lowering statin drug previously shown to reduce carotid artery wall thickening due to plaque. Another group took low doses of the beta-blocker drug metoprolol; a third group took both drugs; and a fourth group took a placebo.
All participants had ultrasound studies of their carotid arteries before enrollment in the study, and at 18 months and three years after starting treatment. Ultrasound is an imaging technique that allows a detailed assessment of the artery. It can pick up thickening of the artery wall, which is indicative of atherosclerosis.
The benefit of metoprolol was evident at 18 months. Metoprolol slowed the progression of atherosclerosis by about 40%. The participants taking metoprolol also tended to have fewer strokes and heart attacks during this time.
"It is very interesting but not unexpected that metoprolol was found to slow down atherosclerosis in the carotid artery, which is an artery where this disease process is common," Björn Fagerberg, MD, PhD, tells WebMD.