Stroke: strategies for primary prevention

Stroke is a leading cause of morbidity and mortality in North America. Primary prevention of stroke includes lifestyle modifications and measures to control blood pressure, cholesterol levels, diabetes mellitus, and atrial fibrillation. Lowering blood pressure in patients with hypertension prevents both hemorrhagic and ischemic stroke (relative risk reduction, 35 to 45 percent). Observational studies suggest that higher cholesterol levels are associated with an increased risk of ischemic stroke, and treatment with statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) may reduce the risk of fatal and nonfatal stroke by 25 percent. Although high-quality evidence linking tighter glucose control with stroke reduction is lacking, good glucose control and aggressive treatment of hypertension and hyperlipidemia in patients with diabetes mellitus are recommended. The risk of stroke in patients with atrial fibrillation and the role of anticoagulation depend on factors such as age and the presence of comorbid conditions. Controversy exists about the roles of angiotensin-converting enzyme inhibitors and aspirin in the primary prevention of stroke.     

When to operate in carotid artery disease

Carotid endarterectomy has proved to be beneficial in the prevention of stroke in selected patients. The procedure is indicated in symptomatic patients with carotid-territory transient ischemic attacks or minor strokes who have carotid artery stenosis of 70 to 99 percent. With a low surgical risk, carotid endarterectomy provides modest benefit in symptomatic patients with carotid artery stenosis of 50 to 69 percent. Platelet antiaggregants and risk factor modification are recommended in symptomatic patients with less than 50 percent stenosis. In the Asymptomatic Carotid Atherosclerosis Study, carotid endarterectomy was beneficial in patients who had asymptomatic carotid artery stenosis of 60 percent or greater and whose general health made them good candidates for elective surgery, provided that the arteriographic and surgical complication rates were low. However, in asymptomatic patients, surgery reduced the absolute risk of stroke by only 1 percent per year.     

Patient knowledge and expectations for functional recovery after stroke

OBJECTIVE: Understanding the causes and outcomes of stroke is important for stroke survivors and may affect their success in rehabilitation and their risk of recurrent stroke; therefore, this study was performed to assess the knowledge and expectation of functional recovery in stroke patients undergoing acute inpatient rehabilitation. DESIGN: Survey study of 50 consecutive stroke patients undergoing inpatient rehabilitation at a single urban rehabilitation hospital. RESULTS: Forty-six percent of participants were able to correctly identify whether they had sustained a cerebral infarct or hemorrhage. Rehabilitation length of stay was, on average, 1 wk longer than anticipated by patients. Patients overestimated their functional abilities on initial assessment and at discharge compared with staff assessments, with some improvement in accuracy for discharge predictions. Ninety-four percent of participants expected to be discharged home, and most achieved this goal. Although no participant anticipated discharge to a nursing home, 10% of patients were discharged to this location. CONCLUSIONS: Knowledge of stroke and its treatment was limited, and expectations for recovery tended to exceed actual accomplishments. There are significant areas of opportunity for enhanced educational efforts for stroke patients undergoing inpatient rehabilitation.     

Stroke-related knowledge and health behaviors among poststroke patients in inpatient rehabilitation

OBJECTIVE: To measure stroke knowledge and prestroke personal health behaviors of stroke patients undergoing inpatient rehabilitation and their caregivers. DESIGN: Prospective cohort. SETTING: Academic rehabilitation hospital. PARTICIPANTS: A total of 130 stroke patients and 85 caregivers interviewed after ischemic stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The Stroke Education Assessment measured stroke knowledge and prestroke personal health behaviors. RESULTS: Large deficiencies in patient and caregiver stroke knowledge were found. Fifty-two percent of patients could not name any stroke risk factors, 52% were unable to name a stroke warning sign, and 35% were unable to identify appropriate actions to take in a stroke emergency. Older patients were less knowledgeable than younger patients. Caregivers were more knowledgeable than patients. Regarding prestroke personal health behaviors, 28% of patients reported medication nonadherence, 26% did not see their primary care physician in the preceding year, and less than 40% of patients with diabetes or hypertension reported diets consistent with these diagnoses. CONCLUSIONS: Stroke patients participating in inpatient rehabilitation and their caregivers have large gaps in stroke knowledge and have suboptimal personal health behaviors, thereby putting patients at high risk for recurrent stroke. Our finding highlights the need to develop stroke-education programs for rehabilitating patients that are effective in closing these gaps in knowledge and personal health behaviors.     

Carotid endarterectomy for stroke prevention

Minor neurologic signs or transient ischemic attacks (TIAs) precede stroke in 50 percent of patients. In men, antiplatelet therapy decreases the risk of recurrent TIA and stroke. Carotid endarterectomy for TIA is now one of the most commonly performed vascular operations. Preoperatively, the arterial anatomy of the patient must be carefully studied by conventional angiography or digital subtraction angiography. The goal of surgery is to eliminate the atherosclerotic plaque and restore the artery to its normal size with a smooth intima.     

Warfarin therapy for atrial fibrillation in the elderly

OBJECTIVE: To evaluate a clinical practice model that addresses special needs for managing anticoagulation in a community-dwelling elderly population with atrial fibrillation and high risk of stroke. METHODS: Medical records of 18 patients (mean age 82 y) followed by the Geriatric Ambulatory Program over 2 years, with a target international normalized ratio (INR) of 2.0-3.0, were reviewed. Risk factors for stroke, number and results of INR tests, suspected reasons for suboptimal response, and adverse events were analyzed. Patients were defined as having cognitive impairment if they had a Folstein Mini-Mental State Exam score < or = 26. Functional impairment was defined by > or = 2 disabilities in activities of daily living. RESULTS: Eighty-three percent (15/18) had > or = 2 additional stroke risk factors. Fifty-one percent (273/541) of INR responses were therapeutic. Female gender (p = 0.015) and cognitive (p = 0.019) and functional impairment (p = 0.001) were associated with supratherapeutic INR response. All patients with cognitive impairment and 85% of those with functional impairment received caregiver support for medication administration. There were 4 minor bleeding events and no thromboembolic events. The mean number of medications was 9.3 in those with bleeding versus 6.8 in those without bleeding (p = 0.052). CONCLUSIONS: Elderly patients with high stroke risk achieved therapeutic INR responses. However, those with significant cognitive or functional impairment require caregiver support and special consideration for anticoagulation management.     

Cryptogenic stroke and patent foramen ovale

A stroke of unknown etiology is commonly referred to as cryptogenic and is diagnosed in a considerable patient population of especially young age. Numerous case-control studies revealed a strong and consistent association between cryptogenic stroke and the presence of a patent foramen ovale. This relationship corroborates paradoxical embolism as likely stroke mechanism in this patient population. In approximately twenty-five percent of patients with cryptogenic stroke, the patent foramen ovale is accompanied by an atrial septal aneurysm, which considerably heightens the risk for recurrent neurological events. Therapeutic measures for secondary prevention in this patient population encompass medical treatment with antiplatelet agents or anticoagulants and surgical or percutaneous closure of patent foramen ovale. Currently, randomised clinical studies compare medical treatment with closure of patent foramen ovale to determine the most effective treatment strategy in this patient population.     

Poststroke shoulder pain: a prospective study of the association and risk factors in 152 patients from a consecutive cohort of 205 patients presenting with stroke.

BACKGROUND AND PURPOSE: Shoulder pain is known to retard rehabilitation after stroke. Its causes and prognosis are uncertain. This study describes the incidence of poststroke shoulder pain prospectively, in an unselected stroke population in the first 6 months after stroke and identifies risk factors for developing pain. METHODS: 297 patients with possible stroke were screened and stroke diagnosed in 205 cases. The 152 patients entered the study of which 123 patients were assessed up to 6 months. This cohort, with a mean age of 70.6 years, was examined at 2 weeks, 2, 4, and 6 months. A history of shoulder pain, Barthel score, anxiety and depression score were recorded. Full neurological and rheumatological examination was undertaken, using the contralateral side as a control. Pain outcome and stroke outcome was recorded at subsequent visits. RESULTS: 52 (40%) patients developed shoulder pain on the same side of their stroke. There was a strong association between pain and abnormal shoulder joint examination, ipsilateral sensory abnormalities and arm weakness. Shoulder pain had resolved or improved at 6 months in 41 (80%) of the patients with standard current treatment. CONCLUSIONS: Shoulder pain after stroke occurred in 40% of 123 patients surviving, consenting and not too unwell to participate. This included 52 patients of an original cohort of 205 patients presenting with stroke. Eighty percent of patients made a good recovery with standard treatment Patients with sensory and or motor deficits represent at risk sub-groups.     

Post stroke shoulder pain: more common than previously realized.

Stroke is a common disease often requiring rehabilitation, which may be prolonged by shoulder pain. The true incidence of post stroke shoulder pain has not been fully evaluated. In order to establish this, we undertook a prospective study of 123 consecutive patients with a diagnosis of acute stroke during a 6-month period. Patients were assessed by interview, full rheumatological and neurological examination, 14 days post stroke, for a history of shoulder pain according to predetermined criteria. In addition, Barthel Index, HAD score and pain scores were also recorded. Twenty-five percent of patients developed shoulder pain within 2 weeks of their stroke. There was a statistically significant association with ipsilateral sensory impairment (p < 0.005), abnormal rheumatological examination (p < 0.001) and depression score (p < 0.005).We conclude that post stroke shoulder pain is more common than previously realized and in addition to abnormal shoulder joint examination may also be associated with upper limb sensory impairment. Thorough neurological examination is required to detect sensory loss and hence establish patients at risk. This is probably best done by a structured proforma.     

Efficacy of folic acid supplementation in stroke prevention: new insight from a meta-analysis

Aims: There are growing data and a continuing controversy over the efficacy of folic acid supplementation in stroke prevention. We conducted a meta‐analysis based on relevant, up‐to‐date published randomised trials to further examine this issue. Methods: Relative risk (RR) was used to measure the effect of folic acid supplementation on risk of stroke with a fixed‐effects model. Results: Overall, folic acid supplementation reduced the risk of stroke by 8% (n = 55,764; RR: 0.92; 95% CI: 0.86–1.00, p = 0.038). In the 10 trials with no or partial folic acid fortification (n = 43,426), the risk of stroke was reduced by 11% (0.89; 0.82–0.97, p = 0.010). Within these trials, a greater beneficial effect was observed among trials with a lower percent use of statins [≤ 80% (median); 0.77; 0.64–0.92, p = 0.005], and a meta‐regression analysis also suggested a positive dose‐response relationship between percent use of statins and log‐RR for stroke associated with folic acid supplementation (p = 0.013). A daily dose of 0.4–0.8mg folic acid appeared to be adequate for stroke prevention in comparison with larger doses. In the remaining five trials conducted in populations with folic acid fortification (n = 12,338), folic acid supplementation had no effect on stroke risk (1.03; 0.88–1.21, p = 0.69). Conclusions: Our analysis indicated that folic acid supplementation is effective in stroke prevention in populations with no or partial folic acid fortification. In addition, a greater beneficial effect was observed among trials with a lower percent use of statins. Our findings underscore the importance of identifying target populations that can particularly benefit from folic acid therapy.     

卒中单元内早期康复训练对患者肢体功能恢复的影响

目的:探讨卒中单元内早期康复训练对患者肢体运动功能恢复的影响.方法:将40例急性脑卒中患者随机分为康复组和对照组各20例,康复组给予体位护理、肢体被动活动、坐位训练、床上训练及神经肌肉治疗,对照组给予常规护理.结果:康复组治愈率15%,好转率80%,致残率5%,平均住院21d;对照组治愈率5%,好转率15%,致残率80%,平均住院35d,两组比较差异有显著性(P＜0.05).结论:开展卒中单元内的早期康复训练可降低致残率,缩短住院时间,值得临床推广.     

首发脑卒中患者卒中相关知识的调查

目的调查首次发病的脑卒中患者脑卒中相关知识。方法对259例首次发病住院的脑卒中患者问卷调查患者的脑卒中相关知识及其获取知识的途径。结果患者对高血压容易并发脑卒中、脑卒中早期治疗重要性、脑卒中早期常见的偏瘫症状有所了解,缺少脑卒中其他知识如危险因素、高血压病标准等方面的知识。结论需要大力加强脑脑卒中防治知识的教育。     

Antithrombotic therapy for stroke prevention in patients with atrial fibrillation

Atrial fibrillation(AF) is a common arrhythmia that is an important independent risk factor for stroke. The overall risk of stroke in AF patients averages about 5%/y, but with wide variation depending on the presence of coexistent thromboembolic risk factors, which include increasing age, history of hypertension, previous stroke or transient ischemic attack(TIA), and diabetes. AF patients with prior stroke or TIA are at highest risk(about 12%/y). Adjusted-dose warfarin(target INR 2.0-3.0) is highly efficacious for preventing stroke in AF patients, and is safe for selected patients. Aspirin has a modest effect on reducing stroke. Warfarin is recommended for high-risk AF patients who can safely receive it. Aspirin may be indicated for those with a low stroke risk and for those who cannot receive warfarin.     

Decision-Making in Clinical Practice: Oral Anticoagulant Therapy in Patients with Non-valvular Atrial Fibrillation and a Single Additional Stroke Risk Factor

Approximately 1 in 3–4 patients presenting with an ischemic stroke will also have atrial fibrillation (AF), and AF-related strokes can be effectively prevented using oral anticoagulant therapy (OAC), either with well-controlled vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs). In addition, OAC use (both VKAs and NOACs) is associated with a 26% reduction in all-cause mortality (VKAs) or an additional 10% mortality reduction with NOACs relative to VKAs. The decision to use OAC in individual AF patient is based on the estimated balance of the benefit from ischemic stroke reduction against the risk of major OAC-related bleeding [essentially intracranial hemorrhage (ICH)]. Better appreciation of the importance of VKAs’ anticoagulation quality [a target time in therapeutic range (TTR) of ≥70%] and the availability of NOACs (which offer better safety compared to VKAs) have decreased the estimated threshold for OAC treatment in AF patients towards lower stroke risk levels. Still, contemporary registry-based data show that OAC is often underused in AF patients at increased risk of stroke. The uncertainty whether to use OAC may be particularly pronounced in AF patients with a single additional stroke risk factor, who are often (mis)perceived as having a “borderline” or insufficient stroke risk to trigger the use of OAC. However, observational data from real-world AF cohorts show that the annual stroke rates in such patients are higher than in patients with no additional stroke risk factors, and OAC use has been associated with reduction in stroke, systemic embolism, or death in comparison to no therapy or aspirin, with no increase in the risk of bleeding relative to aspirin. In this review article, we summarize the basic principles of stroke risk stratification in AF patients and discuss contemporary real-world evidence on OAC use and outcomes of OAC treatment in AF patients with a single additional stroke risk factor in various real-world AF cohorts.     

The preoperative cerebrovascular consultation: common cerebrovascular questions before general or cardiac surgery

All types of health care providers may be called on to evaluate the risk of ischemic stroke related to an upcoming surgical procedure, particularly in patients with established cerebrovascular disease. We outline possible mechanisms contributing to perioperative stroke, summarize available data on the stroke risk associated with selected surgeries, and highlight recognized risk factors. We then provide recommended answers to some of the questions commonly encountered at the preoperative cerebrovascular consultation: What is the appropriate time interval between a stroke and elective surgery? What is the perioperative stroke risk for patients with established carotid or vertebrobasilar large artery stenosis, and what are the cardiac implications of detecting a cerebrovascular large artery stenosis? Should patients with a large artery stenosis undergo prophylactic revascularization procedures before undergoing general surgery? What treatment is appropriate for patients with both coronary artery and carotid or vertebrobasilar large artery stenosis? What is the appropriate perioperative management of antiplatelet and anticoagulant medications with respect to stroke risk?     

Basilar and middle cerebral artery reactivity in patients with migraine

BACKGROUND: Migraine has been reported as a possible risk factor for ischemic stroke. The mechanisms underlying this association are unknown. OBJECTIVES: To evaluate cerebrovascular reactivity to hypercapnia in the anterior and posterior circulation of patients with migraine, as reduced cerebrovascular reactivity is associated with a predisposition to stroke in various clinical conditions. METHODS: Using transcranial Doppler ultrasonography, changes in flow velocity during apnea were measured in both middle cerebral arteries and in the basilar artery of 15 control subjects and 30 patients with migraine (15 with aura and 15 without aura) during an attack-free period. Cerebrovascular reactivity was evaluated using the breath-holding index, which is calculated by dividing the percent increase in mean flow velocity recorded during a breath-holding episode by its duration (in seconds) after a normal inspiration. RESULTS: Vascular reactivity in the middle cerebral arteries was similar in patients and controls and significantly lower in the basilar artery of patients with migraine with aura compared with the other 2 groups (P <.0001). CONCLUSIONS: These findings show that in patients with migraine with aura, there is an impairment in the adaptive cerebral hemodynamic mechanisms in the posterior circulation. This fact could have pathogenetic implications since the association between migraine and stroke frequently regards patients with migraine with aura, and cerebral infarcts occur more commonly in the vertebrobasilar district.     

Cerebral infarction

Diabetes mellitus is the second major risk factor for ischemic stroke. Recent increase in atherothrombotic stroke appears to be related with recent increasing of diabetes. Diabetes is, however, a risk factor not only for atherothrombotic stroke but also for lacunar stroke because there is no difference in prevalence of diabetes between atherothrombotic and lacunar strokes. Diabetes can be a risk factor for cardioembolic stroke as well because the major cause of cardioembolic stroke is atrial fibrillation, and diabetes is a risk factor for stroke in patients with atrial fibrillation. Acute ischemic stroke should be classified into above three subtypes according to the brain and artery imaging as well as cardiac sources of embolism. In hyper-acute patients within 3 hours of onset and without early ischemic signs on CT or ischemic lesions less than one third of the hemisphere on magnetic resonance diffusion-weighted imaging, thrombolytic therapy with alteplase is indicated. In acute stroke patients later than 3 hours of onset, argatroban, heparin, and ozagrel are indicated for atherothrombotic, cardioembolic, and lacunar stroke, respectively. For stroke prevention, total management is required by simultaneous treatments for all risk factors existed. In secondary prevention for stroke, in addition to the more strict control of risk factors antithrombotic therapy is required, that is, antiplatelet therapy is indicated for non-cardioembolic stroke, and anticoagulant therapy is indicated for cardioembolic stroke.     

A review of stroke in patients with hypertension and coronary artery disease: Focus on calcium channel blockers

Stroke is a major cause of morbidity and mortality worldwide. Hypertension is one of the most important risk factors for stroke - increasing the risk significantly. The presence and severity of coronary artery disease (CAD), which often coexists with hypertension, also predicts an increased risk of stroke. Lowering blood pressure (BP) to target in patients with hypertension can significantly reduce the incidence of fatal and non-fatal stroke. Effective BP control is even more important in CAD patients who are at greater risk of stroke. Data regarding the effects of antihypertensive therapy on stroke in patients with angina or CAD are limited and have been variable. To date, BP management strategies in patients with CAD have relied on small subsets of data based on high-risk hypertensive patients. Results with calcium channel blockers (CCBs) have been more positive than those with other classes of antihypertensive agents. Findings from the ACTION trial have provided a significant insight into the benefits of CCBs in patients with CAD and hypertension. Nifedipine gastrointestinal therapeutic system (GITS), in addition to best practice therapy for stable angina pectoris, contributes to a significant reduction in the risk of stroke in patients with CAD and hypertension who are at high risk and require effective BP control. Moreover, the incidence of stroke is significantly related to baseline BP, which may be an important factor to consider when deciding on treatment strategies in high-risk patients with CAD.     

淮南地区急性脑血管病患者的危险因素分析

[目的]探讨脑血管病的流行病学特征以及各种危险因素对不同类型卒中的影响,观察淮南地区人群脑血管病的发病特点.[方法]连续收集从2008年6月至2010年4月首次发病入院且资料完整的急性脑血管病患者773例,其中缺血性684例,出血性89例.分析卒中患者的发病年龄、分型特点及危险因素等.[结果]淮南地区773例首发卒中患者的平均发病年龄为(64.96±11.86)岁,其中出血性卒中组平均年龄显著低于缺血性卒中组(P＜0.001),男性卒中患者的平均发病年龄显著低于女性卒中患者(P＜0.01).缺血性卒中发病高峰年龄为60～79岁,出血性卒中发病高峰年龄为45～64岁,两者有显著性差异(p＜0.001).高血压是出血性和缺血性卒中的首要危险因素,其次为吸烟、饮酒、心脏病和糖尿病史.入院首次血压(收缩压和舒张压),出血性卒中组均显著高于缺血性卒中组(P ＜0.001).高血压史、吸烟史、饮酒史在出血性卒中组出现的频率均高于缺血性卒中组(P＜0.01、P＜0.05、P＜0.01).出血性卒中组血清高密度脂蛋白显著高于缺血性卒中(P＜0.001).本组患者就诊距发病时间＜24 h者出血性卒中约占75.0％～82.4％,缺血性卒中占48.8％～ 57.3％.[结论]淮南地区出血性卒中发病高峰年龄明显小于缺血性卒中,与国内多数报道一致;高血压是导致各类卒中的重要危险因素;血清高密度脂蛋白胆固醇增高、吸烟、饮酒与出血性卒中密切相关.