A nationwide stroke prevention study shows that medication and lifestyle changes remain safer and more effective at preventing strokes than stenting in patients with narrowed brain arteries.
The study analyzed long-term health outcomes from a multicenter clinical trial, which included University of Florida Health researchers Brian Hoh, M.D., the James and Newton Eblen associate professor of neurosurgery, radiology and neuroscience, and Michael Waters, M.D., Ph.D., assistant professor of neurology and neuroscience and UF Health Stroke Program director. The findings appeared in the Oct. 26 issue of The Lancet.
Enrollment in the trial was halted two years ago when it became apparent that stenting was associated with a higher risk of early strokes and death at early time points. The final results after long-term follow-up support medical management as preferable in this disease.
"This study emphasizes the critical importance of modifying the stroke risk factors of hypertension, high cholesterol and diabetes, as well as lifestyle factors such as exercise and smoking cessation," Waters said.
The multicenter study was conducted in 50 sites across the United States.
Nearly 800,000 people suffer a stroke each year, and about 10 percent of those strokes result from a narrowed artery inside the brain. For decades, doctors have treated these patients with blood-thinning medications that help prevent clot formation and with drugs to lower cholesterol and blood pressure. Recent advances in surgical techniques and tools have allowed neurosurgeons to adapt procedures such as stenting, which is used to open clogged arteries in the heart, for use in stroke patients.
To assess the effectiveness of the new treatments, the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis, or SAMMPRIS, trial, which was funded by the National Institutes of Health, enrolled 451 patients at high risk of repeated stroke. All participants had a brain artery with at least a 70 percent narrowing that had already caused a stroke or a transient ischemic event, commonly known as a mini-stroke.
Participants were separated into two groups. Patients in one group had a metal stent surgically inserted into the narrowed brain artery, while patients in the other group did not. Both groups received the same medications and were contacted regularly by lifestyle modification coaches, who encouraged participants to exercise more, stop smoking, improve their diet and lose weight. They also had routine follow-up.
For the final analysis, the scientists followed the patients for at least two years after treatment. Some patients were followed for as long as four years.
In August 2012, the early results of SAMMPRIS led the Food and Drug Administration to change the criteria for using the "wingspan" stent tested in the trial.
The new guidelines restrict use of this stent to patients with at least a 70 percent blockage who already have had two previous strokes while on aggressive medical management.
"Our highest level of clinical research is the prospective randomized trial. In this study, we randomized patients with symptoms from narrowed brain arteries to receive either a stent or aggressive medical treatment, and over one year, aggressive medical management appears to be safer," Hoh said. "This does not shut the door on stenting, however, as we know that there are patients who fail medical treatment and need opening of their brain arteries to prevent stroke because their brains are not receiving enough oxygen and blood flow."