Researcher says screenings vital to reduce stroke rate
A leading stroke researcher says the aging of the American population means that more people are at risk for stroke, and unless new approaches are developed to reduce stroke incidence, it will surpass heart attacks and cancer as the major cause of long-term disability and premature death.
"…The heart will no longer be the cause of most sudden deaths, leaving behind an ever-growing population of the elderly disabled by stroke and vascular dementia …," writes James F. Toole, M.D., and colleagues from Wake Forest University Baptist Medical Center in an editorial in the current issue of the Journal of the American Medical Association (JAMA).
Toole, past president of the International Stroke Federation, says using ultrasound to screen people for narrowed arteries in the neck is the best way to identify people at excess risk for stroke. He recommends that men undergo a baseline ultrasound screening of their carotid arteries between the ages of 50 and 60, depending on their overall health. He says that both men and women with diabetes, hypertension or a family history of stroke – all of which increase the risk of stroke – should be screened even earlier.
The North Carolina Stroke Association chapter of the National Stroke Association has conducted a pilot study using ultrasound to screen people for stroke. The results are currently being evaluated.
More than 500,000 new strokes occur each year in the United States, and it has been estimated that carotid artery disease may be responsible for 20 percent to 30 percent of them. "The critical dilemma is how best to identify patients at excess risk for stroke … before events occur," writes Toole in JAMA.
In an editorial in the British Medical Journal in September, Toole, a professor of neurology at Wake Forest Baptist, said that screening is the best way to identify vessel disease that is pre-clinical, or before symptoms develop.
Toole says that effective ways to prevent stroke make the screenings especially important. These include drugs to prevent clotting, aspirin, exercise, diet, smoking cessation and surgery. Recent research confirmed the value of surgery to open narrowed neck vessels in reducing stroke risk. "We now know definitively that we can reduce stroke risk by half with surgery to clean out narrowed arteries leading to the brain – even in patients who have no symptoms," said Toole. "We should offer this option to more patients, as well as begin screening seemingly healthy individuals for stroke risk."
From 1987 to 1993, Toole and colleagues conducted a study of 1,662 participants in the United States and Canada. The Endarterectomy for Asymptomatic Carotid Artery Stenosis study, or ACAS, found that 11 percent of participants who were treated with medication alone had strokes. In the surgery group, the incidence was 5.1 percent – a 53 percent reduction.
Recently, ACST (Asympotomatic Carotid Stenosis Trial), a similar study of more than 3,000 patients in Europe, found the same results. Both studies looked at the value of surgery, called carotid endarterectomy, in people who have no symptoms, but whose carotid arteries were narrowed by at least 60 percent, a condition called carotid artery stenosis. The surgery is typically offered only to patients who have symptoms of an impending stroke. "If medical intervention fails, ACST has proved once and for all that carotid endarterectomy can be worth the risk …," said Toole in the British Medical Journal.
Tooles co-authors on the JAMA editorial are David Sane, M.D., associate professor of cardiology, and Kerstin Bettermann, M.D., Ph.D., assistant professor of neurology, both with Wake Forest Baptist. Toole is director of the medical centers Stroke Research Center.
Karen Richardson | EurekAlert!