NEW YORK (Reuters Health) – The most effective way to prevent a first stroke is not well established – what works for the primary prevention of myocardial infarction doesn’t necessarily work for stroke.

Nonetheless, newly-released guidelines for the primary prevention of stroke provide health professionals with an overview on established and emerging risk factors for stroke and evidence-based recommendations for reducing the risk of a first stroke.

The guidelines, from the American Heart Association (AHA) and the American Stroke Association, are available online now and will be published in the February 2011 print issue of the journal Stroke. Dr. Larry B. Goldstein, director of the Duke Stroke Center at Duke University Medical Center in Durham, North Carolina, chaired the guideline writing panel.

Stroke exacts a “staggering” human and economic toll, the panel notes. Roughly 795,000 Americans suffer a stroke each year; most of these (77%) are first events. About 6.4 million Americans are stroke survivors, although many are left with functional impairments or permanent disability requiring institutional care.

“Persons at high risk for or prone to stroke can now be identified and targeted for specific interventions,” the panel notes.

The new guidelines revise 2006 guidelines on this topic. According to an AHA statement, for the first time, the guidelines address stroke as a broad continuum of related events, including transient ischemic attack (TIA), ischemic stroke, and hemorrhagic stroke. They also, for the first time, focus an individual patient-oriented approach to stroke prevention, as opposed to a population-based approach.

The writing group used a systematic literature review (covering the time since the last document was published in 2006 up to April 2009), with reference to previously published guidelines, personal files, and expert opinion to “summarize existing evidence, indicate gaps in current knowledge and when appropriate, formulate recommendations,” they say.

“Well-documented and modifiable” risk factors for stroke, the guidelines state, include hypertension, exposure to cigarette smoke, diabetes, atrial fibrillation and certain other cardiac conditions, dyslipidemia, carotid artery stenosis, sickle cell disease, postmenopausal hormone therapy, poor diet, physical inactivity, and obesity and body fat distribution.

“Less well-documented or potentially modifiable” risk factors include metabolic syndrome, excessive alcohol consumption, drug abuse, use of oral contraceptives, sleep-disordered breathing, migraine, hyperhomocysteinemia, elevated lipoprotein(a), hypercoagulability, inflammation, and infection.

The guidelines also review the use of aspirin for primary stroke prevention. They state that while aspirin doesn’t prevent a first stroke in low-risk persons or those with diabetes or asymptomatic peripheral artery disease, it’s recommended for individuals whose risk is high enough for the reduction in stroke risk to outweigh the bleeding risks of aspirin.

The guidelines also include these prevention updates based on recent research:

* Individuals who make healthy lifestyle choices – including not smoking, eating a low-fat diet high in fruits and vegetables, drinking alcohol in moderation, exercising regularly and maintaining a normal body weight – lower their risk of a first stroke as much as 80% compared with those who don’t make such changes. The preventive benefit increases with each positive change adopted.

* Emergency room clinicians should try to identify patients at high risk for stroke and consider making referrals, conducting screenings or beginning preventive therapy.

* Although genetic screening for stroke among the general population isn’t recommended, it may be appropriate in certain circumstances, depending on family history and other factors.

* The usefulness of stenting in persons with a narrowed carotid artery as compared to endarterectomy remains uncertain. Because of advances in standard medical therapies (including changes in lifestyle, antihypertensive, antiplatelet and cholesterol lowering therapy) the usefulness of either procedure in persons with asymptomatic carotid artery stenosis is unclear. The guidelines advise clinicians to make decisions whether to perform either procedure on a case-by-case basis.

* General population screening for carotid artery narrowing isn’t recommended.

Reference:

Guidelines for the Primary Prevention of Stroke. A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Stroke;2011:42.