In May 2021, the American Heart Association (AHA)/American Stroke Association (ASA) updated one of its flagship guidelines—the secondary prevention of stroke guideline—for the first time since 2014, with the key takeaway being an emphasis on identifying the cause of a stroke or transient ischaemic attack (TIA) to inform specific prevention strategies for reducing the risk of additional strokes. 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 (Ann Arbor, USA), spoke to NeuroNews to discuss this “critically important” strategy in stroke prevention, as well as an increased focus on thinking about “the whole person” when treating stroke.
Having a stroke or TIA increases the risk of having a stroke in the future—this is something that is widely accepted by the stroke community. However, new and more granular data on this phenomenon are emerging all the time, and, as such, the AHA/ASA saw fit to formally introduce the “2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischaemic Attack” this year, publishing it in the journal Stroke. One of the most important new recommendations in this guideline is for healthcare professionals to perform diagnostic evaluations on patients to determine the cause of their first stroke or TIA within 48 hours of symptom onset.
“We are recommending that this diagnostic workup is done early, and the reason for that is because there are a few causes of stroke that have a high risk immediately after the event,” Kleindorfer said. On this subject, she cited the fact that some patients who have even a mild TIA due to a blocked artery in their neck, for example, may have an elevated risk of a far more severe stroke that can cause permanent damage within the following week—but that this risk can be addressed if the blocked artery is detected early on. “My hope is that this will help change the care approach, and help people recognise that it [the diagnostic workup] really is something that is urgent and needs to be done—so that we can then direct the right treatments to prevent the next event from happening.”
Prevention based on cause
According to Kleindorfer, the structure of the guideline’s latest form differs from the previous document, with “pages and pages of text” giving way to more manageable “knowledge chunks”, as well as tables and algorithms to help clinicians “find the topic or disease that [they] are really interested in”. More specifically, this “user-friendly” format begins by outlining the different causes of a stroke or TIA under different sections, before moving on to various treatment recommendations based on this. Kleindorfer stated that the hope is this updated structure “will make it easier for the busy clinician to be able to scan and find what they need within the document for the particular patient they are seeing that day”.
However, this restructuring is driven by more than just convenience. As the AHA/ASA outlined in a press release accompanying the update, “many risk factors for a second stroke remain poorly managed among stroke survivors” and, as such, the new guideline emphasises the need for clinicians to investigate the cause of a stroke or TIA—whether it is blockages in the large arteries in the neck or brain, small arteries in the brain being damaged from high blood pressure or diabetes, irregular heart rhythms, or something else—when deciding how to treat a given patient. “We recommend that—if you come into the hospital—somebody should look at your heart, the arteries in your neck, bloodwork, and other diagnostic tests as needed,” Kleindorfer added. “Those things were never really laid out specifically before.”
A more holistic approach
As well as this reshuffling of priorities in how recurrent stroke is managed in the short term, Kleindorfer stated that the concept of behavioural interventions now features more prominently in the guideline too. “One of our top 10 messages—which was actually slightly controversial when we first introduced it—was that, if you want to change people’s behaviour, handing them a brochure is not enough,” she said. “I think educating our patients is really important,” Kleindorfer added, “but just handing them a pamphlet and nothing else is not going to work. That is something of a paradigm shift, because a lot of doctors want to talk about the benefits of aspirin versus clopidogrel, versus anticoagulation, and my first question is always: do you know that they are taking it? And, do you know that they can afford it? These kinds of questions are much more important than whether the patient should be on 50mg or 81mg of aspirin.”
“We are really asking people to consider the whole person, and to think about ways to prevent stroke beyond just the latest technology and the dosing of medications,” she added. Considerations about compliance, as well as social determinants of health, and the patient’s overall motivations and understanding of their own disease, were all factors highlighted by Kleindorfer here. She went on to state that an infrastructure setup within existing health systems—including, for example, social workers, psychologists, or physical therapists—is what will be required in order to truly influence patient behaviour. “The doctor can start the process, but it really needs to be followed up with a system to support the patient, and their family, so that they understand what the patient is going through as well,” Kleindorfer noted.
The importance of up-to-date guidelines
Kleindorfer described updates such as this as “critical”, also asserting that “an outdated guideline is no use—in fact, it can be harmful”. “These big topic-type guidelines like secondary prevention of stroke […] are what we call the flagship guidelines, and they need to be reviewed and revised every few years,” she added. While Kleindorfer said the secondary stroke guideline has typically been updated every five years in the past, a handful of advisory statements that were put out between 2014 and this year’s revision have meant the guideline was still able to keep pace with the most important pieces of research and information to have come to light throughout this period.
Regarding what may be subject to change over the course of the coming five-year timeframe—prior to the next potential secondary stroke guideline update—Kleindorfer stated that several studies are ongoing right now that are likely to have been completed by then. These include research into stenosis in the neck and how to manage carotid artery narrowing, and also cryptogenic strokes or embolic stroke of undetermined source (ESUS)—in light of recent evidence that anticoagulation may not be the best way to treat these patients. “So, if I had to try to predict the future for the next guideline, I would say some of the carotid artery studies will be out by then, and some of the ESUS studies will be out by then too,” she concluded. “And, there are always some newer technologies going on with devices in the heart that I think may be interesting for preventing cardioembolic strokes.”
For patients who have survived a stroke or TIA, the secondary prevention guidelines recommend:
- Managing their vascular risk factors, especially high blood pressure, as well as Type 2 diabetes, cholesterol, and not smoking.
- Limiting salt intake and/or following a Mediterranean diet—typically with emphasis on monounsaturated fat, plant-based foods, and fish consumption, with either high extra virgin olive oil or nut supplementation.
- If they are capable of physical activity, 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.
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 if needed.
- Prescribing antithrombotic therapy, including antiplatelet medications, or anticoagulant medications to prevent blood clotting, for nearly all patients who do not have contraindications.
- 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 have caused a stroke or TIA.
- In some patients, it is now reasonable to consider percutaneously closing a patent foramen ovale via a less invasive, catheter-based surgical procedure.
