ATLANTA – While it is well known that a stroke or a transient ischemic attack (TIA) signals higher risk for stroke in the future, a new guideline emphasizes that identifying the cause of the initial event can better guide specific prevention strategies to reduce the risk of additional strokes.
The updated guidance from the American Heart Association/American Stroke Association, created with significant VA input, was published recently in the journal Stroke.1
The authors pointed out that the overwhelming majority of strokes in the United States, 87%, are ischemic. While a transient ischemic attack, TIA, occurs when an artery is blocked for a short amount of time and doesn’t usually cause permanent brain injury, when blood flow is blocked, either by clots or plaques, ischemic stroke can lead to serious disability or even death, according to the report.
The guideline panel noted that recurrent stroke rates have dropped substantially in the United States from 8.7% in the 1960s to 5% in the 2000s, as prevention strategies have improved. Yet, it pointed out that many risk factors for a second stroke remain poorly managed among stroke survivors.
The “2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack” strongly urges healthcare professionals to perform diagnostic evaluations to determine the cause of the first stroke or TIA within 48 hours of symptom onset.
Once that is ascertained, the guideline includes a section outlining treatment recommendations based on the cause of the initial stroke/TIA. Possible underlying causes include blockages in large arteries in the neck or brain, small arteries in the brain damaged from high blood pressure or diabetes, irregular heart rhythms and many other potential causes.
“It is critically important to understand the best ways to prevent another stroke once someone has had a stroke or a TIA,” explained Dawn O. Kleindorfer, MD, FAHA, chair of the guideline writing group, and professor and neurology department chair at the University of Michigan School of Medicine in Ann Arbor. “If we can pinpoint the cause of the first stroke or TIA, we can tailor strategies to prevent a second stroke.”
Steven J. Kittner, MD, MPH, of the VA Maryland Healthcare System in Baltimore and Linda S. Williams, MD, of the Richard L. Roudebush VAMC in Indianapolis also were on the writing committee. Christianne Roumie, MD, MPH, of the VA Tennessee Valley Healthcare System in Nashville was a peer reviewer.
Secondary prevention guidelines recommend that patients who have survived a stroke or TIA manage their vascular risk factors, especially high blood pressure but also Type 2 diabetes, cholesterol and triglyceride levels. They also are urged to quit smoking, limit salt intake and follow a Mediterranean diet.
If patients are capable of physical activity, they should be urged to engage in moderate-intensity aerobic activity for at least 10 minutes four times a week or vigorous-intensity aerobic activity for at least 20 minutes twice a week.
“In fact, approximately 80% of strokes can be prevented by controlling blood pressure, eating a healthy diet, engaging in regular physical activity, not smoking and maintaining a healthy weight,” emphasized Amytis Towfighi, MD, vice chair of the guideline writing group and director of neurological services at the Los Angeles County Department of Health Services.
Updated treatment recommendations for clinicians include:
- Using multidisciplinary care teams to personalize care for patients and employing shared decision-making with the patient to develop care plans that incorporate a patient’s wishes, goals and concerns.
- Screening for and diagnosing atrial fibrillation and starting blood-thinning medications to reduce recurrent events.
- Carotid endarterectomy, surgical removal of a blockage or, in some cases, the use of a stent in the carotid artery, should be considered for patients with narrowing arteries in the neck.
- Aggressive medical management of risk factors and short-term dual anti-platelet therapy are preferred for patients with severe intracranial stenosis suspected of causing the stroke or TIA.
- Percutaneously closing, a less invasive, catheter-based surgical procedure, might be considered in a patent foramen ovale, a small and fairly common heart defect.
The guideline also strongly encourages clinicians to precribe antithrombotic therapy, including antiplatelet medications or anticoagulant medications for nearly all patients who don’t have contraindications. But it adds some cautions.
“However, the combination of antiplatelets and anticoagulation is typically not recommended for preventing second strokes, and dual antiplatelet therapy, taking aspirin along with a second medicine to prevent blood clotting, is recommended short-term, only for specific patients: those with early arriving minor stroke and high-risk TIA or severe symptomatic stenosis,” the authors explain.
The guideline is accompanied by a systematic review article, published simultaneously, “Benefits and Risks of Dual Versus Single Antiplatelet Therapy for Secondary Stroke Prevention.” The review paper, chaired, by Devin L. Brown, M.D., M.S., is a meta-analysis of three short-duration clinical trials on dual antiplatelet therapy (DAPT) and concludes DAPT may be appropriate for select patients. The review authors note: “Additional research is needed to determine: the optimal timing of starting treatment relative to the clinical event; the optimal duration of DAPT to maximize the risk-benefit ratio; whether additional populations excluded from POINT and CHANCE [two of the trials examined], such as those with major stroke, may also benefit from early DAPT; and whether certain genetic profiles eliminate the benefit of early DAPT.”
“The secondary prevention of stroke guideline is one of the American Stroke Association’s ‘flagship’ guidelines, last updated in 2014,” Kleindorfer added. “There are also a number of changes to the writing and formatting of this guideline to make it easier for professionals to understand and locate information more quickly, ultimately greatly improving patient care and preventing more strokes in our patients.”
- Dawn O. Kleindorfer, Amytis Towfighi, Seemant Chaturvedi, Kevin M. Cockroft, Jose Gutierrez, Debbie Lombardi-Hill, Hooman Kamel, Walter N. Kernan, Steven J. Kittner, Enrique C. Leira, Olive Lennon, James F. Meschia, Thanh N. Nguyen, Peter M. Pollak, Pasquale Santangeli, Anjail Z. Sharrief, Sidney C. Smith, Tanya N. Turan, Linda S. Williams. 2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack: A Guideline From the American Heart Association/American Stroke Association. Stroke, 2021; DOI: 10.1161/STR.0000000000000375