This Secondary Prevention of Stroke module focuses on management recurrent stroke risk reduction in patients who have experienced an initial stroke or transient ischemic attack. In some cases, this module will also guide healthcare providers with guidance for individuals at high risk of a stroke or TIA based on current health status and the significant presence of one or more vascular risk factors.
The 2017 update of the Canadian Stroke Best Practice Recommendations Secondary Prevention of Stroke module reinforces the growing and changing body of research evidence available to guide stroke prevention services. A coordinated and organized approach to assessment and aggressive risk factor management is emphasized throughout this module.
Highlights of significant updates and new additions to the Secondary Prevention of Stroke best practice recommendations for 2017 that are based on new and emerging evidence include:
- addition of a framework for providing stroke prevention services, and a detailed list of care elements that should be included to distinguish stroke prevention services;
- revisions to the recommendations for the triage and assessment of risk of recurrent stroke after TIA/minor stroke and suggested urgency levels for investigations and initiation of management strategies (Section 1);
- smoking cessation has been added to the lifestyle section rather than a separate section (Section 2);
- minor updates to blood pressure management, lipid management and diabetes and stroke sections to reflect recent clinical trial releases and guideline updates by the respective medical societies (Sections 3, 4, 5 respectively);
- refinements to stroke prevention and management of atrial fibrillation and anticoagulant use (Section 7);
- clarifications on timing for carotid interventions (Section 8);
- antithrombotic management in people with cervicocephalic artery dissection
- With the recent completion of the REDUCE and CLOSE trials, and long-term follow-up from the RESPECT trial, the recommendations for people with patent foramen ovale have been updated (Section 9).
- Heart failure has been added to the Cardic Issues section (Section 9)
- updates to Heart and Stroke Taking Charge patient information on best practices related to stroke prevention
- updates to Heart and Stroke public information on risk factors for heart disease and stroke
- updates to the HSF Stroke Assessment and Prevention Pocket Guide to align with all updates to the recommendations in this module
- Sleep Apnea and Stroke Prevention: Sleep apnea is a recognized risk factor for stroke, and a condition that appears in some patients both before and following a stroke. However, the recently released findings of the SAVE trial (2016) has demonstrated that although treatment with CPAP of moderate-to-severe sleep apnea in patients with a history of coronary and cerebrovascular disease is associated with benefits including reduced daytime sleepiness and improved health-related quality of life, there is insufficient evidence to recommend CPAP for secondary stroke prevention, and we do not recommend routine screening of patients with stroke for OSA. In light of the SAVE results, sleep apnea screening and treatment are no longer routinely recommended for secondary prevention of stroke and accordingly have removed recommendations for universal screening and treatment in stroke patients. Screening and treatment for sleep apnea symptoms should be performed as part of routine primary care based on the presence or absence of sleep apnea symptoms, as is currently done for patients without stroke.
Emerging Trends in Stroke Prevention Research
A key tenant to stroke prevention is knowing one’s risk for stroke. A sizeable list of modifiable and nonmodifiable risk factors for stroke has been amassed (Goldstein, Bushnell, Adams et al, 2011). Of these risk factors, family history, or genetic predisposition, is considered one of the most important risk factors. However, despite numerous epidemiological studies providing evidence for a genetic component to stroke (Flossmann, Schulz and Rothwell, 2004), the extent of this predisposition is largely unknown (Dichgans, 2007). Moreover, genetic predisposition to stroke may act at several levels by: (1) contributing to standard risk factor that have a known genetic component such as hypertension or diabetes; (2) interacting with environmental factors; (3) contributing directly to an intermediate phenotype such as atherosclerosis; or (4) affecting latency to stroke, infarct size or stroke outcome (Dichgans, 2007). Clearly, the quest to identify the underlying molecular mechanisms contributing to stroke risk has been challenging at best (Traylor M, Farrall M, Holliday EG, et al, 2012).
Recent studies examining genetic risk factors for stroke found genetic predisposition to stroke to vary based on age and stroke subtype (Flossmann, Schulz and Rothwell, 2004; Jerrard-Dunne, Cloud, Hassan and Markus, 2003; Jood, Ladenvall, Rosengren, Blomstrand and Jern, 2005; Schulz, Flossmann and Rothwell, 2004). A meta-analysis of genome-wide associations studies undertaken by the METASTROKE Collaboration confirmed that although genetic variants were detected in patients with ischemic stroke when compared to controls, all genetic variations were specific to a stroke subtype (Traylor M, Farrall M, Holliday EG, et al, 2012). The METASTROKE Collaboration posited the implications of their findings were twofold: (1) to maximize success of genetic studies in ischemic stroke, detailed stroke subtyping is required; and (2) different genetic pathophysiological mechanisms appear to be associated with different stroke subtypes, possibly leading to pharmacotherapy having different effects in different stroke subtypes. Moving forward, detailed subtyping may be required to illustrate differing effect of pharmacological profiles in secondary stroke prevention. In addition, inherited single-gene disorders can also lead to abnormalities that predispose persons toward stroke, usually a specific sub type. For example, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) syndrome, is associated with a mutation of the NOTCH3 gene, which manifests independently of traditional stroke risk factors (Tan RY and Markus, 2015). The condition results in damage to small blood vessels, which reduces blood flow, leading to recurrent subcortical cerebral infarctions. Accordingly, stroke in younger persons should raise suspicion of the presence of one of these highly penetrant mutation, either established genes (e.g. CADASIL, Fabry) or emerging ones (e.g. COL4A2). These genetic abnormalities may be identified using next generation sequencing technology, in selected individuals.
Guideline Development Methodology:
The Canadian Stroke Best Practice Recommendations present high-quality, evidence-based stroke care guidelines in a standardized framework to support healthcare professionals across all disciplines. Implementation of these recommendations is expected to reduce practice variations and closing the gaps between evidence and practice. The recommendations are targeted to health professionals throughout the health system who care for those affected by stroke. Health system policy makers, planners, funders, senior managers, and administrators who are responsible for the coordination and delivery of stroke services within a province or region will also find this document relevant and applicable to their work. The methodology for updating the recommendations includes twelve distinct steps to ensure a thorough and rigorous process. These include the following (details available online):
- Heart and Stroke Foundation Secondary Prevention of Stroke Canadian Stroke Best Practice Recommendations Introduction and Overview CSBPR Sixth Edition FINAL (November 22th, 2017) Page 9 of 96 1. Establish expert inter professional writing group for module, as well as stroke survivors and/or caregivers
- Systematic search, appraisal and update of research literature up to September 2017
- Systematic search and appraisal of external reference guideline recommendations
- Update of evidence summary tables
- Writing group review and revision of existing recommendations, development of new recommendations as required
- Submission of proposed chapter update to the Canadian Stroke Best Practices Advisory Committee
- Internal review of proposed chapter update. Feedback to writing group, completion of edits.
- External review, and final edits based on feedback.
- Update of educational materials and implementation resources
- Final approvals, endorsement and translation of chapter
- Public release & dissemination of final chapter update
- Continue with ongoing review and update process.
The detailed methodology and explanations for each of these steps in the development and dissemination of the Canadian Stroke Best Practice Recommendations is available in the Canadian Stroke Best Practice Recommendations Overview and Methodology manual available on the Canadian stroke best practices website at http://www.strokebestpractices.ca/
Conflicts of Interest: All potential participants in the recommendation development and review process are required to sign confidentiality agreements and to declare all actual and potential conflicts of interest in writing. Any conflicts of interest that are declared are reviewed by the Chairs of the Best Practices Advisory Committee and appropriate HSF staff members for their potential impact. Potential members of any writing group who have conflicts that are considered to be significant are not selected for advisory or writing group membership. Participants who have conflicts for one particular topic area are identified at the beginning of discussions for that topic, and if it is the chair, then another non-conflicted participant assumes the chair role for that discussion to ensure balanced discussions. Declarations of Conflict of interest for writing group members can be found in Appendix One.
Assigning Evidence Levels: The writing group was provided with comprehensive evidence tables that include summaries of all high quality evidence identified through the literature searches. The writing group discusses and debates the value of the evidence and through consensus develops a final set of proposed recommendations. Through their discussions, additional research may be identified and added to the evidence tables if consensus on the value of the research is achieved. All recommendations are assigned a level of evidence ranging from A to C, according to the criteria defined in Table 1. When developing and including “C-Level” recommendations, consensus is obtained among the writing group and validated through the internal and external review process. This level of evidence is used cautiously, and only when there is a lack of stronger evidence for topics considered important system drivers for stroke care (e.g., transport using ambulance services or some screening practices). An additiononal category for Clinical Considerations has been added for the Sixth Edition. Included in this section are expert opinion statements in response to reasonable requests from a range of healthcare professionals who seek guidance and direction from the experts on specific clinical issues faced on a regular basis in the absence of any evidence on that topic
- Writing Group Members and External Reviewers, Declaration of Conflicts of Interest
- Definitions for Stroke Prevention
- Figure Two: HSF-CSBPR Core Elements of Stroke Prevention Services Underlying Framework
- Table Two: HSF CSBPR Core Elements of Stroke Prevention Services
- Section 1 – Initial Risk Stratification and Management of Non-Disabling Stroke and TIA
- Section 2 – Lifestyle And Risk Factor Management
- Section 3 – Blood Pressure Management
- Section 4 – Lipid Management
- Section 5 – Diabetes Management
- Section 6 – Antiplatelet Therapy for Ischemic Stroke and TIA
- Section 7 – Anticoagulation for Individuals with Stroke and Atrial Fibrillation
- Section 8 – Management of Extracranial Carotid Disease and Intracranial Atherosclerosis
- Section 9 – Cardiac Issues in Individuals with Stroke
- Appendix Three: Pharmacotherapy for Smoking Cessation in Patients with Stroke and TIA
Citing the Prevention of Stroke 2017 Module
Theodore Wein, M Patrice Lindsay, Robert Côté, Norine Foley, Joseph Berlingieri, Sanjit Bhogal, Aline Bourgoin, Brian H Buck, Jafna Cox, Dion Davidson, Dar Dowlatshahi, Jim Douketis, John Falconer, Thalia Field, Laura Gioia, Gord Gubitz, Jeffrey Habert, Sharon Jaspers, Cheemun Lum, Dana McNamara Morse, Paul Pageau, Mubeen Rafay, Amanda Rodgerson, Bill Semchuk, Mukul Sharma, Ashkan Shoamanesh, Arturo Tamayo, Elisabeth Smitko, David J Gladstone, on behalf of the Heart and Stroke Foundation Canadian Stroke Best Practice Committees, International Journal of Stroke. 2017
We invite comments, suggestions, and inquiries on the development and application of the Canadian Stroke Best Practice Recommendations.
Please forward comments to the Heart and Stroke Foundation’s Stroke Team at firstname.lastname@example.org