Identifying the cause of a stroke or transient ischaemic attack (TIA)—sometimes called a “mini-stroke”—can lead to specific prevention strategies to reduce the risk of additional strokes, according to updated guidelines from the American Stroke Association (ASA), a division of the American Heart Association (AHA). The guidelines were published in the ASA journal Stroke.
“It is critically important to understand the best ways to prevent another stroke once someone has had a stroke or a TIA,” said Dawn O Kleindorfer, chair of the guideline writing group, and professor and chair of the department of neurology at the University of Michigan School of Medicine in Ann Arbor, USA. “If we can pinpoint the cause of the first stroke or TIA, we can tailor strategies to prevent a second stroke.”
Having a stroke or TIA increases the risk for additional strokes in the future. According to an AHA press release, as prevention strategies have improved, studies have noted a reduction in recurrent stroke rates from 8.7% in the 1960s to 5.0% in the 2000s—yet many risk factors for a second stroke remain poorly managed among stroke survivors.
A new recommendation of the “2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack” is for healthcare professionals to perform diagnostic evaluations to determine the cause of the first stroke or TIA within 48 hours of symptom onset. The guideline includes a section outlining treatment recommendations based on the cause of the initial stroke or TIA. Underlying causes could be related to 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.
For patients who have survived a stroke or TIA, the secondary prevention guidelines recommend managing vascular risk factors, especially high blood pressure, Type 2 diabetes, cholesterol, triglyceride levels and not smoking, as well as limiting salt intake and/or following a Mediterranean diet, and engaging in moderate-intensity aerobic activity for at least 10 minutes four times per week, or vigorous-intensity aerobic activity for at least 20 minutes twice per week, if they are capable of physical activity.
“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,” said Amytis Towfighi, vice-chair of the guideline writing group, and director of neurological services at the Los Angeles County Department of Health Services in Los Angeles, USA.
For healthcare professionals, the updated treatment recommendations highlighted in the guideline include:
- Using multidisciplinary care teams to personalise 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.
- Prescribing antithrombotic therapy, including antiplatelet medications or anticoagulant medications to prevent blood clotting, for nearly all patients who do not have contraindications. 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 in the short term—but only for specific patients with early-arriving minor stroke and high-risk TIA, or severe symptomatic stenosis.
- Carotid endarterectomy, surgical removal of a blockage or, in select 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 antiplatelet therapy are preferred for patients with severe intracranial stenosis thought to cause the stroke or TIA.
- In some patients, it is now reasonable to consider percutaneously closing the small and fairly common heart defect known as a patent foramen ovale.
The guideline is accompanied by a systematic review article, published simultaneously, entitled “Benefits and Risks of Dual Versus Single Antiplatelet Therapy for Secondary Stroke Prevention.” The review paper, chaired by Devin L Brown, 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 maximise 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 ASA’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.”