Stroke Prevention and Control

• The World Stroke Organization (WSO) was established in October 2006 from the merger of the International Stroke Society (ISS) and the World Stroke Federation (WSF), the two lead organizations representing stroke globally. The mission of WSO is to provide access to stroke care and to promote research and teaching in this area that will improve the care of stroke victims throughout the world. This organization emphasizes lifestyle choices for the prevention of first stroke and appropriate medications for the prevention of recurrent stroke.

• Approximately 795,000 people in the United States have a stroke each year, and stroke is the third leading cause of deaths annually. The death rate for stroke fell by 34% over the past 10 years, but despite overall declines in stroke deaths, stroke incidence may be increasing.¹

• Stroke prevention efforts can reduce stroke incidence by 50%, and a healthy lifestyle is associated with an 80% lower risk of a first stroke.

• The first goal should be to identify persons at high risk for stroke including those with nonmodifiable risk factors for whom more intense treatment of modifiable risk factors may be indicated.¹  (See Stroke risk factors)

• Hypertension is the most important modifiable risk factor. There is a lower stroke rate in patients with a blood pressure of <120 mm Hg than <140 mm Hg. The blood pressure goal is <140/90 mm Hg, and <130/80 mm Hg in diabetics and those with chronic kidney disease. Beta-blockers are less effective than other agents in stroke prevention.¹

• Treatment of diabetics for stroke prevention should include a statin, and an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker. The benefit of aspirin for stroke risk reduction has not been demonstrated in diabetes, but should be considered in those with high cardiovascular disease risk.¹

• Adjusted-dose warfarin (target international normalized ratio, 2.0-3.0) is recommended for all patients with non-valvular atrial fibrillation deemed to be at high risk and those at moderate risk who are at low risk for warfarin. Antiplatelet therapy with aspirin is indicated in atrial fibrillation at low risk or at moderate risk with patient preference or increased risk for warfarin. Dual antiplatelet therapy is warranted in high-risk patients unsuitable for warfarin.¹

•  Carotid artery stenosis is clinically (and hemodynamically) significant at a reduction in luminal diameter of >70% on validated duplex, or >80% on computed tomography angiography or magnetic resonance angiography. Combination duplex ultrasound with a contrast imaging study provides optimal sensitivity, specificity, and accuracy of stenosis and allows imaging of intracranial vessels.¹

• Patients with carotid stenosis should be treated with lifestyle changes and medical therapy. Selection of asymptomatic patients for carotid revascularization (CEA) by surgery or stent should be guided by comorbid conditions, age, and patient preferences. Prophylactic CEA can be performed with <3% morbidity and mortality in asymptomatic carotid stenosis with >60% stenosis by angiography, or 70% by validated duplex ultrasound.¹

• Population screening for asymptomatic carotid disease is not recommended. ¹ 

Stroke and cholesterol lowering medications 

• Low levels of LDL and high levels of HDL are associated with decreased risk of stroke. Despite screening guidelines and evidence of the efficacy of statins, majority of patients with stroke do not receive adequate lipid lowering therapy or control of lipids. ²

• Treatment of dyslipidemias for stroke prevention should include a statin in persons at high risk for coronary artery disease and diabetes, possibly in combination with niacin in patients with low HDL cholesterol or elevated lipoprotein (a).¹ Pretreatment with statins was found to reduce the recurrence of stroke and to result in more favorable outcomes for patients.³

• Among cholesterol-lowering treatments, statins are the most effective at decreasing the risk of  stroke, and  their benefit is proportional to the percent reduction of LDL (low-density lipoprotein) cholesterol.⁴ Benefits are seen even among people without high LDL. At this time, the best evidence powerfully demonstrates stroke and TIA patients should be prescribed high dose statin therapy for secondary stroke prevention.⁵

• Rosuvastatin reduced the incidence of ischemic stroke by more than half among men and women with even low levels of LDL in the JUPITER Trial.⁶

Sources

1. Goldstein L B., Bushnell CD, Adams RJ, et al. Guidelines for the primary prevention of stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. Feb 2011;42(2):517-584.

2. Lewis A, Segal A. Hyperlipidemia and primary prevention of stroke: does risk factor identification and reduction really work? Curr Atheroscler Rep. Jul 2010;12(4):225-229.

3. Lakhan SE, Bagchi S, Hofer M. Statins and clinical outcome of acute ischemic stroke: a systematic review. Int Arch Med. 2010;3:22.

4.De Caterina R, Scarano M, Marfisi R, et al. Cholesterol-lowering interventions and stroke: insights from a meta-analysis of randomized controlled trials. J Am Coll Cardiol. Jan 19 2010;55(3):198-211.

5. Huisa BN, Stemer AB, Zivin JA. Atorvastatin in stroke: a review of SPARCL and subgroup analysis. Vasc Health Risk Manag. 2010;6:229-236.

6. Everett BM, Glynn RJ, MacFadyen JG, Ridker PM. Rosuvastatin in the prevention of stroke among men and women with elevated levels of C-reactive protein: justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER). Circulation. Jan 5 2010;121(1):143-150.