April 13, 2017
CHARLESTON, SC – Exercise leads to a five-fold decrease in recurrent stroke in patients with intracranial stenosis, according to researchers at the Medical University of South Carolina (MUSC) in an article published in a recent issue of Neurology. Intracranial stenosis, the narrowing of arteries in the brain, is the most common cause of stroke worldwide.
This is the first report showing an association between exercise and prevention of recurrent stroke. The current American Heart guidelines for patients with intracranial stenosis recommend lowering blood pressure and cholesterol but do not mention exercise. How much exercise was needed to attain this benefit? “At least vigorous walking for about 30 minutes, three to five times each week,” said Tanya N. Turan, M.D., director of the MUSC Stroke Division and lead author of the article. She has a simple message for physicians who treat stroke patients. “Tell your patients to exercise,” she said. “Think outside of the pillbox.”
Study participants self-reported exercise using the six-point Patient-Centered Assessment and Counseling for Exercise (PACE) score. Those who scored above three met the target for physical activity and received benefit. Moderate exercise was defined as brisk walking or slow cycling for at least 10 minutes at a time, and vigorous activity as jogging or fast cycling for at least 20 minutes at a time. There was evidence for a dose-dependent effect with exercise, with greater protection from vascular events seen with more exercise. All study participants were enrolled free of charge in a commercially available lifestyle modification program, which included regular coaching on healthy lifestyle behaviors. Control of other risk factors, such as smoking, body mass index, and glycated hemoglobin, did not significantly affect vascular outcomes.
Moderate to vigorous physical activity was by far the strongest predictor of an improved outcome. Indeed, patients who did not regularly engage in moderate to vigorous exercise were up to five times as likely to experience a recurrent stroke or other vascular event. Reaching targets for systolic blood pressure (greater than 140 mm Hg, greater than 130 mm Hg for diabetics) and low-density lipoprotein cholesterol (greater than 70 mg/d) also significantly reduced the risk of secondary stroke, myocardial infarction or a vascular event. Approximately half of the study participants met these targets on average during the study. Those who did not were 2.1 and 1.8 times more likely, respectively, to experience a recurrent stroke, myocardial infarction or vascular event.
Turan believes that, given these findings, the next version of the guidelines may be more supportive of exercise for secondary stroke prevention in patients with intracranial stenosis.
“When I counsel my patients with this condition, I talk with them about those two primary risk factors (blood pressure and cholesterol) but also mention the impact of exercise and tell them that they can do it without having to take an extra pill and that it could have the biggest impact,” she said.
While it is true that stroke patients can have physical or emotional barriers to exercise, including stroke-related disability or depression, this analysis demonstrates that access to a lifestyle modification program can substantially increase their willingness to exercise. The percentage of study participants who were at target for physical activity increased from 32 percent at study entry to 56 percent by the four-month follow-up visit. Lifestyle modification programs, such as the one used in the study, are commercially available and can be used to help motivate stroke patients to meet exercise targets. These programs can cost $400 to $500 annually and may be out of the reach of some patients; however, insurance reimburses for these costs in some cases. For patients who cannot afford to participate in a formal lifestyle modification program, physicians and their health care staff can work toward the same goal by consistently encouraging exercise in order to prevent recurrent stroke. Many hospitals also offer cardiac and stroke rehabilitation services that promote exercise.
Founded in 1824 in Charleston, The Medical University of South Carolina is the oldest medical school in the South. Today, MUSC continues the tradition of excellence in education, research, and patient care. MUSC educates and trains more than 3,000 students and 700 residents in six colleges (Dental Medicine, Graduate Studies, Health Professions, Medicine, Nursing, and Pharmacy), and has nearly 14,000 employees, including approximately 1,500 faculty members. As the largest non-federal employer in Charleston, the university and its affiliates have collective annual budgets in excess of $2.4 billion, with an annual economic impact of more than $3.8 billion and annual research funding in excess of $250 million. MUSC operates a 700-bed medical center, which includes a nationally recognized Children's Hospital, the Ashley River Tower (cardiovascular, digestive disease, and surgical oncology), Hollings Cancer Center (a National Cancer Institute-designated center), Level I Trauma Center, Institute of Psychiatry, and the state’s only transplant center. In 2017, for the third consecutive year, U.S. News & World Report named MUSC Health the number one hospital in South Carolina. For more information on academic programs or clinical services, visit musc.edu. For more information on hospital patient services, visit MUSChealth.org.