Stroke

Health Topics A-Z

Health Topics A-Z

Stroke

Highlights

Signs of Stroke

The American Stroke Association advises everyone to recognize these signs of stroke:

Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
Sudden confusion, trouble speaking or understanding
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden, severe headache with no known cause

F.A.S.T.

The acronym FAST is an easy way to remember signs of stroke and what to do if you think a stroke has occurred. (The most important is to immediately call 9-1-1 for emergency assistance.) FAST stands for:

(F)ACE. Ask the person to smile. Check to see if one side of the face droops.
(A)RMS. Ask the person to raise both arms. See if one arm drifts downward.
(S)PEECH. Ask the person to repeat a simple sentence. Check to see if words are slurred and if the sentence is repeated correctly.
(T)IME. If a person shows any of these symptoms, time is essential. It is important to get to the hospital as quickly as possible. Call 9-1-1. Act FAST.

Recovery and Rehabilitation

The length of recovery time following a stroke depends on the severity of the stroke. Patients who have had a mild stroke may be able to improve in time on their own without formal rehabilitation therapy. For those who have had more severe strokes, rehabilitation programs include:

Exercise training to improve strength, flexibility, and coordination
Retraining muscles to reduce spasticity and regain function
Speech therapy to regain lost speech and comprehension, and improve communication skills
Swallowing training to learn how to safely eat and drink
Occupational therapy to practice personal activities of daily living and regain independence

It is also very important for patients to make lifestyle changes (quitting smoking, following a heart-healthy diet) and take any necessary medications to prevent a second stroke.

Introduction

Blood Flow Blockage. The brain receives about 25% of the body's oxygen, but it cannot store it. Brain cells require a constant supply of oxygen to stay healthy and function properly. Therefore, blood needs to be supplied continuously to the brain through two main arterial systems:

The carotid arteries come up through either side of the front of the neck. (To feel the pulse of a carotid artery, place your fingertips gently against either side of your neck, right under the jaw.)
The basilar artery forms at the base of the skull from the vertebral arteries, which run up along the spine, join, and come up through the rear of the neck.

The Circle of Willis is the joining area of several arteries at the bottom (inferior) side of the brain. At the Circle of Willis, the internal carotid arteries branch into smaller arteries that supply oxygenated blood to over 80% of the cerebrum.

A reduction of, or disruption in, blood flow to the brain is the primary cause of a stroke. Blockage for even a short period of time can be disastrous and cause brain damage or even death.

Click the icon to see an image of the brain.

A stroke is usually defined as two types:

Ischemic (caused by a blockage in an artery)
Hemorrhagic (caused by a tear in the artery's wall that produces bleeding in the brain)

The consequences of a stroke, the type of functions affected, and the severity, depend on where in the brain it has occurred and the extent of the damage.

Ischemic Stroke

Ischemic strokes are by far the more common type, causing over 80% of all strokes. Ischemia means the deficiency of oxygen in vital tissues. Ischemic strokes are caused by blood clots that are usually one of three types:

Thrombotic stroke
Embolic stroke
Lacunar stroke

Thrombotic or Large-Artery Stroke and Atherosclerosis. The thrombotic stroke accounts for about 60% of all strokes. It usually occurs when an artery to the brain is blocked by a thrombus (blood clot) that forms as the result of atherosclerosis (commonly known as hardening of the arteries). These strokes are also sometimes referred to as large-artery strokes. The process leading to thrombotic stroke is complex and occurs over time:

The arterial walls slowly thicken, harden, and narrow until blood flow is reduced, a condition known as stenosis.
As these processes continue, blood flow slows. In addition, other events contribute to the coming stroke:
The arteries become calcified, lose elasticity, and become susceptible to tearing. In this event, the thrombus (blood clot) forms.
The blood clot then blocks the already narrowed artery and shuts off oxygen to part of the brain. A stroke occurs.

Embolic Strokes and Atrial Fibrillation. An embolic stroke is usually caused by a dislodged blood clot that has traveled through the blood vessels (an embolus) until it becomes wedged in an artery. Embolic strokes account for about 25% of all strokes and may be due to various conditions:

In about 15% of embolic strokes, the blood clots originally form as a result of a rhythm disorder known as atrial fibrillation. This abnormal rhythm is a rapid quivering beat in the upper chambers of the heart (the atria). Because of the irregular pumping, some blood may remain in the heart chamber where it forms clots, which can then break off and travel to the brain as emboli. Between 2 - 4% of patients with atrial fibrillation without any history of TIA or stroke will have an ischemic stroke over the course of a year. The risk generally increases with age.
Emboli can originate from blood clots that form at the site of artificial heart valves in 4 - 5% of patients.
Patients with heart valve disorders such as mitral stenosis are at increased risk for clots when they also have atrial fibrillation.
Emboli can also occur after a heart attack or in association with heart failure.
Rarely, emboli are formed from fat particles, tumor cells, or air bubbles that travel through the bloodstream.

Lacunar Strokes. Lacunar infarcts are a series of very tiny, ischemic strokes, which cause clumsiness, weakness, and emotional variability. They are actually a subtype of thrombotic stroke and constitute about 38% of this major group. In some populations, such as among Japanese, they are the most common stroke subtypes. They can also sometimes serve as warning signs for a major stroke.

Silent Brain Infarctions. Many elderly people have silent brain infarctions, small strokes that cause no apparent symptoms. They are detected in 10 - 38% of elderly patients who undergo imaging tests for problems other than stroke. The presence of silent infarctions indicates an increased risk for future stroke, and are often contributors to mental impairment in the elderly. Smokers and people with hypertension are at particular risk.

Transient Ischemic Attacks (TIAs)

Transient ischemic attacks (TIAs) are mini-ischemic strokes, usually caused by tiny emboli (clots often formed of pieces of calcium and fatty plaque) that lodge in an artery to the brain. They typically break up quickly and dissolve but they do temporarily block the supply of blood to the brain. The mental or physical disturbances resulting from TIAs generally clear up in less than a day, with nearly all symptoms resolving in less than an hour.

TIA should be taken very seriously and treated as aggressively as a stroke. Both stroke and TIA increase the risk for a subsequent stroke. Moreover, the risk for having another stroke can be as high as 40% within 5 years.

Hemorrhagic Stroke

Over 15% of strokes occur from hemorrhage (sudden bleeding) in the brain. In a healthy brain, brain cells called neurons are protected from exposure to blood by the blood-brain barrier, a wall of tiny vessels and structural cells. In a hemorrhagic stroke, however, this barrier is broken.

Hemorrhagic strokes may be categorized by how and where they occur.

Parenchymal, or cerebral, hemorrhage strokes. These strokes occur within the brain and account for about 10% of all strokes. They are most often the result of hypertension exerting excessive pressure on arterial walls already damaged by atherosclerosis. Heart attack patients who have been given drugs to break up blood clots or blood-thinning drugs have a slightly elevated risk of this type of stroke.
Subarachnoid hemorrhagic strokes. This other major hemorrhagic stroke accounts for about 5% of all strokes. This kind of stroke occurs when a blood vessel on the surface of the brain bursts, leaking blood into the subarachnoid space, an area between the brain and the skull. They are usually caused by the rupture of an aneurysm, a weakening in the blood vessel wall, which is often an inherited trait.
Arteriovenous malformation (AVM) is an abnormal connection between arteries and veins. If it occurs in the brain and ruptures, it can also cause a hemorrhagic stroke.

Symptoms

People at risk and partners or caretakers of people at risk for stroke should be aware of the general symptoms. The stroke victim should get to the hospital as soon as possible after these warning signs appear. It is particularly important for people with migraines or frequent severe headaches to understand how to distinguish between their usual headaches and symptoms of stroke.

The American Stroke Association lists the following five warning signs of stroke. PEOPLE SHOULD IMMEDIATELY CALL FOR EMERGENCY ASSISTANCE IF THEY EXPERIENCE ANY OF THESE SYMPTOMS:

Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
Sudden confusion, trouble speaking or understanding
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden, severe headache with no known cause

Research indicates that patients receive faster treatment for stroke if they arrive by ambulance rather than coming to the emergency room on their own.

An easy way to remember the signs of stroke, and what to do, is by the acronym "F.A.S.T." If you think you or someone else is having a stroke, the National Stroke Association's F.A.S.T. test advises:

(F)ACE. Ask the person to smile. Check to see if one side of the face droops.
(A)RMS. Ask the person to raise both arms. See if one arm drifts downward.
(S)PEECH. Ask the person to repeat a simple sentence. Check to see if words are slurred and if the sentence is repeated correctly.
(T)IME. If a person shows any of these symptoms, time is essential. It is important to get to the hospital as quickly as possible. Call 9-1-1. Act FAST.

Symptoms of TIAs and Early Ischemic Stroke

The symptoms of a transient ischemic attack (TIA) and early ischemic stroke are similar. In the case of a TIA, however, the symptoms should resolve within 24 hours. Symptoms depend on where the injury in the brain occurs. The origin of the stroke is usually either the carotid or basilar arteries.

Atherosclerosis of internal carotid artery

The build-up of plaque in the internal carotid artery may lead to narrowing and irregularity of the artery's lumen, preventing proper blood flow to the brain. More commonly, as the narrowing worsens, pieces of plaque in the internal carotid artery can break free, travel to the brain, and block blood vessels that supply blood to the brain. This leads to stroke, with possible paralysis or other deficits.

Symptoms From Blockage in the Carotid Arteries. The carotid arteries stem off of the aorta (the primary artery leading from the heart) and lead up through the neck, around the windpipe, and on into the brain. When TIAs or stroke occur from blockage in the carotid artery, which they often do, symptoms may occur in either the retina of the eye or the cerebral hemisphere (the large top part of the brain).

Symptoms include the following:

When oxygen to the eye is reduced, people describe the visual effect as a shade being pulled down. People may develop poor night vision. About 35% of TIAs are associated with temporary lost vision in one eye.
When the cerebral hemisphere is affected, a person can experience problems with speech and partial and temporary paralysis, drooping eyelid, tingling, and numbness, usually on one side of the body. The stroke victim may be unable to express thoughts verbally or to understand spoken words. If the stroke injuries are on the right side of the brain, the symptoms will develop on the left side of the body and vice versa.
Uncommonly, patients may experience seizures.

Symptoms From Blockage in the Basilar Artery. The other major site of trouble, the basilar artery, is formed at the base of the skull from the vertebral arteries, which run up along the spine and join at the back of the head. When stroke or TIAs occur here, both hemispheres of the brain may be affected so that symptoms occur on both sides of the body. The following symptoms may develop:

Temporarily dim, gray, blurry, or lost vision
Tingling or numbness in the mouth, cheeks, or gums
Headache, usually in the back of the head
Dizziness
Nausea and vomiting
Difficulty swallowing
Weakness in the arms and legs, sometimes causing a sudden fall

Such strokes usually occur in the brain stem, which can have profound affects on breathing, blood pressure, heart rate, and other vital functions, but have no affect on thinking or language.

Speed of Symptom Onset. The speed of symptom onset of a major ischemic stroke may indicate its source:

If the stroke is caused by a large embolus (a clot that has traveled to an artery in the brain), the onset is sudden. Headache and seizures can occur within seconds of the blockage.
When thrombosis (a blood clot that has formed within the brain) causes the stroke, the onset usually occurs more gradually, over minutes to hours. On rare occasions it progresses over days to weeks.

Click the icon to see an image of carotid dissection.

Click the icon to see an image of stroke.

Symptoms of Hemorrhagic Stroke

Cerebral Hemorrhage Symptoms. Symptoms of a cerebral, or parenchymal, hemorrhage typically begin very suddenly and evolve over several hours and include:

Headache
Nausea and vomiting
Altered mental states
Seizures

Subarachnoid Hemorrhage. When the hemorrhage is a subarachnoid type, warning signs may occur from the leaky blood vessel a few days to a month before the aneurysm fully develops and ruptures. Warning signs may include:

Abrupt headaches
Nausea and vomiting
Sensitivity to light
Various neurologic abnormalities. Seizures, for example, occur in about 8% of patients.

When the aneurysm ruptures, the stroke victim may experience:

A terrible headache
Neck stiffness
Vomiting
Altered states of consciousness
Eyes may become fixed in one direction or lose vision
Stupor, rigidity, and coma

Risk Factors

New or recurrent strokes affect about 780,000 Americans every year. On average, someone in the United States has a stroke every 40 seconds. Although incidence of stroke has increased, more people are surviving stroke, and the death rate is declining. While age is the major risk factor, people with stroke are likely to have more than one risk factor.

Age

Older Adults. People most at risk for stroke are older adults, particularly those with high blood pressure, who are sedentary, overweight, smoke, or have diabetes. Older age is also linked with higher rates of post-stroke dementia.

Younger Adults. Younger people are not immune, however. About 28% of stroke victims are under age 65.

Gender

In most age groups except older adults, stroke is more common in men than in women. However, it kills more women than men, regardless of ethnic groups. This may be partly due to the fact that women tend to live longer than men, and stroke is more common among older adults. Women account for about 6 in 10 stroke deaths.

Ethnicity

All minority groups, including Native Americans, Hispanics, and African-Americans, face a significantly higher risk for stroke and death from stroke than Caucasians. African-Americans have twice the risk for first-time stroke as Caucasians. The risk is also higher in Asian Americans, although stroke rates appear to be declining in this group. The differences in risk among all groups diminish as people age.

The greatest disparity in risk occurs in young adults. Younger African-Americans are two to three times more likely to experience a stroke than their Caucasian peers and four times more likely to die from one. They also face a higher risk for death from heart disease. African-Americans have a higher prevalence of diabetes and hypertension than other groups. However, studies suggest that socioeconomic factors also affect these differences.

Presence of Other Vascular Disease

Heart disease and stroke are closely tied for many reasons:

Patients with one condition often have risk factors for the other, such as high blood pressure, atherosclerosis (hardening of the arteries), and diabetes.
The risk of stroke increases during surgical procedures involving the coronary arteries, including coronary bypass operations and angioplasty. Coronary bypass poses the greater risk -- about 2 - 5%.
Anti-clotting drugs used for treatment of heart disease and heart attacks slightly increase the risk for hemorrhagic stroke.
A heart attack itself poses a high risk for stroke, which is about 2.5% in the first 6 months and 5% per year thereafter. Patients with a higher risk (about 4%) for stroke within 6 months of a heart attack tend to be older (over age 75), African-American, or to have a history of a previous stroke, atrial fibrillation, hypertension, diabetes, or peripheral artery disease.

Abnormal Blood Pressure

High Blood Pressure (Hypertension). High blood pressure (known medically as hypertension) contributes to 70% of all strokes. Researchers have estimated that controlling blood pressure can prevent nearly 40% of strokes.

Two numbers are used to describe blood pressure phases and may affect stroke risk separately:

The systolic pressure (the higher and first number) is measured as the heart contracts to pump out the blood. Evidence suggests that elevated systolic pressure poses a significant danger for heart and stroke emergencies when diastolic is normal, a condition called isolated systolic hypertension. The wider the spread between the systolic and diastolic measurements, the greater the danger.
The diastolic pressure (the lower and second number) is measured as the heart relaxes to allow blood to refill the heart between beats. Abnormally higher diastolic pressure is a strong predictor of heart attack and stroke in most people with hypertension.
Stroke from Low Blood Pressure (Hypotension). Uncommonly, blood pressure that is too low can reduce oxygen supply to the brain and cause a stroke. This can occur from a heart attack, a major bleeding episode, an overwhelming infection, or rarely, from surgical anesthesia or from over-treatment of high blood pressure.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated, and controlled by medication, lifestyle changes, or a combination of both.

Click the icon to see an image of the risks of untreated hypertension.

Heart Abnormalities Causing Traveling Blood Clots (Embolisms)

Atrial Fibrillation. About one in six strokes are due to atrial fibrillation. This is a heart rhythm disorder in which the atria (the upper chambers in the heart) beat very quickly and nonrhythmically. The blood pools instead of being pumped out, increasing the risk for formation of blood clots that break loose and travel toward the brain. Atrial fibrillation poses a six-fold increased risk for stroke and may also pose a higher risk for complications after a stroke.

Atrial fibrillation is uncommon in people under 60 years old, but about 6% of adults over age 80 have this heart rhythm disorder. In this patient group, the risk for stroke may be higher or lower with the presence of other risk factors, including having heart failure, high blood pressure, certain heart valve abnormalities, diabetes, and a previous history of stroke, TIA, or rheumatic heart disease.

Patent Foramen Ovale. Patent foramen ovale (PFO) is a flap-like opening between chambers of the heart. The foramen ovale is always open during fetal development to enhance blood flow to the fetus. It then typically closes after birth when the lungs take over. However, evidence suggests that it remains open in up to 30% of adults. In such cases, blood moves backward (right to left) through this opening when pressure in the right chamber exceeds the left. Large PFOs are a major cause of stroke, particularly in younger adults. Treatments include anti-clotting drugs and procedures for closing the opening.

Atrial Septal Aneurysm. Atrial septal aneurysm is an inborn condition in which part of the atrium (one of the heart chambers) bulges out. Studies indicate that this may pose a slight risk for stroke in young people.

Smoking

People who smoke a pack a day have almost two and a half times the risk for stroke as nonsmokers. Smoking increases both hemorrhagic and ischemic stroke risk. The risk for stroke may remain elevated for as long as 14 years after quitting, so the earlier one quits the better.

Diabetes and Insulin Resistance

Heart disease and stroke are the leading causes of death in people with diabetes. Diabetes is a strong risk factor for ischemic stroke, perhaps because of accompanying risk factors, such as obesity and high blood pressure. Diabetes does not appear to increase the risk for hemorrhagic stroke. Diabetes is second only to high blood pressure as the main risk factor for stroke. The risk is highest for adults newly diagnosed with type 2 diabetes and patients with diabetes who are younger than age 55. African-Americans with diabetes are at even higher risk for stroke at a younger age.

Studies have also implicated insulin resistance, an important disease mechanism in type 2 diabetes, as an independent factor in the development of atherosclerosis and stroke. With this condition, insulin levels are normal to high, but the body is unable to use the insulin normally to metabolize blood sugar. The body compensates by raising the level of insulin, which in turn increases the risk for blood clots and reduces HDL levels (the beneficial form of cholesterol). Some studies have also reported a worse outcome in patients whose blood sugar levels are high at the time of a stroke.

Obesity and Metabolic Syndrome

Obesity may increase the risk for both ischemic and hemorrhagic stroke independently of other risk factors that often co-exist with excess weight, including insulin resistance and diabetes, high blood pressure, and unhealthy cholesterol level. Weight that is centered around the abdomen (the so-called apple shape) has a particularly high association with stroke, as it does for heart disease, in comparison to weight distributed around hips (pear-shape).

Obesity is particularly hazardous when it is one of the components of metabolic syndrome. This syndrome is diagnosed when three of the following conditions are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Because metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease, people with this syndrome are at increased risk for stroke even before diabetes develops.

Cholesterol and Other Lipids

Although an unhealthy balance of cholesterol and other lipids (fatty compounds) plays a major role in heart disease, its role in stroke is less clear. Different lipids may have different effects:

Ischemic Stroke. The effects of high total cholesterol and LDL levels on stroke are not clear.

Hemorrhagic Stroke. HDL may reduce the risk for hemorrhagic stroke (bleeding in the brain). This is a far less common stroke, however, than ischemic stroke.

In any case, reducing cholesterol is extremely important in anyone with heart disease and abnormal lipid levels.

Genetic and Inborn Factors

Genetics may be responsible for many of the causes of stroke. Studies indicate that a family history of stroke, particularly in one's father, is a strong risk factor for stroke.

Genetics and Subarachnoid Hemorrhage. Genetic factors account for between 7 - 20% of cases of subarachnoid hemorrhage. Ruptured aneurysms that occur in such patients tend to happen at an earlier age, are usually smaller, and are more apt to recur than in those without an inherited condition. A study of people who had suffered subarachnoid hemorrhages found that first-degree relatives of these stroke victims had a high lifetime risk of between 2 - 5%. Some experts recommend screening for aneurysms in people with more than one close relative who suffered a hemorrhagic stroke.

Inherited Disorders that Contribute to Stroke. Some cases of atrial fibrillation may be inherited. Genetic disorders that cause connective tissue disorders are also associated with stroke from hemorrhage; they include polycystic kidney disease, Ehlers-Danlos syndrome type IV, neurofibromatosis type 1, Marfan syndrome, and moyamoya disease.

Specific Genetic Factors Under Investigation. Specific genetic factors are under investigation. They include:

Inherited deficiencies in protein factors C and S, which inhibit blood clotting, may be responsible for certain cases of stroke in young adults.
Factor V Leiden. A genetic mutation in this factor a may be related to blood clotting risks.
Apolipoprotein (Apo) E-4. People with this inherited gene may be at increased risk of stroke. This gene is also associated with Alzheimer's disease.

Mental and Emotional Factors

Stress. One survey revealed that men who had a more intense response to stressful situations, such as waiting in line or problems at work, were more likely to have strokes than those who did not report such distress. In some people, prolonged or frequent mental stress causes an exaggerated increase in blood pressure, which in turn can increase the risk for stroke.

Depression. Depression has also been linked to higher risk for stroke and lower stroke survival rates. In one study, patients with severe depression had a 73% higher risk for stroke, and those with moderate depression had a 25% higher risk than average. The risk for stroke in African-Americans with depression was 160% higher than average.

Migraine and Associated Risk Factors

Studies suggest that migraine or severe headache may be a risk factor for stroke in both men and women, especially before age 50. Overall, between 2 - 3% of ischemic strokes occur in people with a history of migraine. However, in patients under age 45, about 15% of all strokes (and 30 - 60% of strokes in young women) are associated with a history of migraines, particularly migraine with aura. Some evidence suggests that some strokes in these cases may be due to excessive activation of the nervous system and the dehydration from vomiting that occurs during a severe migraine with aura.

The actual risk itself for migraineurs is low, however. Studies suggest specific risk factors for younger women with migraines, particularly those with auras, include taking high-estrogen oral contraceptives (OCs). (Whether progesterone-alone contraceptives carry any risk is unknown.) In migraineurs who take OCs, the risk increases with high blood pressure, smoking, or both.

Infections and Inflammation

Inflammation that occurs with various infections has been associated with stroke.

Varicella Virus. Varicella zoster virus (the virus that causes chicken pox and shingles) has been associated with cerebral vasculitis, a condition in which blood vessels in the brain become inflamed. It is a very rare cause of stroke in children. The virus has also been associated with some cases of stroke in young adults.

Chlamydia Pneumonia. Some investigators suspect that some infections may produce inflammation in the arteries that can lead to stroke over time. (Similar work is underway in heart disease.) Researchers are particularly interested in Chlamydia pneumoniae, a non-bacterial organism that causes mild pneumonia in adults. Chronic infection has been linked with a higher risk for stroke, and evidence of the organism has been observed in thickened inner vessel walls of the carotid arteries in some studies. However, several trials which treated patients with coronary artery disease and evidence of infection with long-term antibiotics failed to demonstrate a reduction in risk for future cardiac events.

Periodontal Disease. A number of studies support an association between periodontal disease and cardiovascular disorders. The added risk may be greater in adults under 65. However, a causal relationship between gum disease and heart disease has not been established.

Peripheral Artery Disease

Peripheral artery disease (PAD) occurs when atherosclerosis affects the extremities, particularly the feet and legs. The major risk factors for heart disease and stroke are also the most important risk factors for PAD. The occurrence of such conditions in combination with PAD often signals more severe forms of heart or circulatory disease.

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

In 2007, the American Heart Association (AHA) issued a scientific statement encouraging doctors to change the way they prescribe pain relief medication for patients at risk for heart disease or stroke. The AHA recommends that at-risk patients first try non-drug methods of pain relief (physical therapy, exercise, weight loss to reduce stress on joints, and heat or cold therapy). If these methods dont work, patients should take the lowest possible dose of acetaminophen (Tylenol) or aspirin. COX-2 inhibitors, such as celecoxib (Celebrex), should be the last resort.

In 2005, the FDA warned that all NSAIDs -- with the exception of aspirin -- carry heart risks. In particular, the NSAIDs ibuprofen (Advil, Motrin) and diclofenac (Cataflam, Voltaren) appear to carry increased risks for heart attack and stroke.

Other Medical or Physical Conditions Associated with a Higher Risk for Stroke

A number of medical or physical conditions may contribute to the risk for stroke:

Sleep apnea. Obstructive sleep apnea, a disorder in which breathing halts briefly but repeatedly during sleep, is present in many patients with high blood pressure. The relationship between sleep apnea and hypertension has been thought to be largely due to obesity, but studies are finding a higher rate of hypertension in people with sleep apnea regardless of their weight. There is some association between the presence of sleep apnea and risk of death in patients who had previously had a stroke
Pregnancy. Pregnancy carries a very small risk for stroke, mostly in women with pregnancy related high blood pressure and in those with cesarean delivery. The risk appears to be higher in the postpartum (post-delivery) period, perhaps because of the sudden change in circulation and hormone levels.
Anti-phospholipid antibodies. Nearly 40% of young people with strokes and 10% of all stroke patients have components of the immune system known as anti-phospholipid antibodies that increase the chance for blood clots.
Sickle-cell anemia. People with sickle-cell anemia are at risk for stroke at a young age.
Drug abuse, particularly with cocaine and, increasingly, methamphetamine, is a major factor in the incidence of stroke in young adults. Anabolic steroids, used for body-building and sports enhancement, also increase risk.

Other Factors Associated with Stroke

Timing. Like heart attack and sudden cardiac death, stroke appears to be more common in the morning hours, perhaps due to a temporary rise in blood pressure at that time. Various studies point to a higher risk for stroke on weekends, Mondays, and holidays. The risk for hemorrhagic stroke may also be higher in the winter, particularly in older people with high blood pressure.

Homocysteine and Vitamin B Deficiencies. Abnormally high blood levels of the amino acid homocysteine, which occur with deficiencies of vitamin B6, B12, and folic acid, may be linked to an increased risk of coronary artery disease and stroke.

Neck Manipulation. Individual case reports have indicated a higher risk for stroke after cervical spine manipulation.

Prognosis

A stroke, the third leading cause of death in the U.S., is always serious. In 2004, more than 150,000 Americans died of stroke, with women accounting for 61% of these stroke deaths. Mortality rates are declining, however. Over 75% of patients survive a first stroke during the first year, and over half survive beyond 5 years.

The Severity of an Ischemic Versus Hemorrhagic Stroke

People who suffer ischemic strokes have a much better chance for survival than those who experience hemorrhagic strokes. Among the ischemic stroke categories, the greatest dangers are posed by embolic strokes, followed by thrombotic and lacunar strokes. Hemorrhagic stroke not only destroys brain cells but also poses other complications, including increased pressure on the brain or spasms in the blood vessels, both of which can be very dangerous. Studies suggest, however, that survivors of hemorrhagic stroke have a greater chance for recovering function than those who suffer ischemic stroke.

Long Term Complications and Deficits

Many patients are left with physical weakness and often have accompanying pain and spasticity. Depending on the severity of the symptoms and how much of the body is involved, these impairments can affect the ability to walk, to rise from a chair, to feed oneself, to write or use a computer, to drive, and many other activities.

Factors that Affect Quality of Life in Survivors

Between 50 - 70% of people recover functional independence after a stroke. However, 15 - 30% of those who survive stroke suffer some permanent disability. The National Institutes of Health (NIH) have devised a scoring system that helps predict the severity and outcome of the stroke by scoring 11 factors (levels of consciousness, gaze, visual fields, facial movement, motor functions in the arm and leg, coordination, sensory loss, problems with language, inability to articulate, and attention). Up to 70% of patients with ischemic strokes who score less than 10 have a favorable outlook after a year, while only 4 - 16% of patients do well if their score is more than 20.

Factors Affecting Recurrence

The risk for recurring stroke is highest within the first few weeks and months of the previous stroke. The risk is about 14% in the first year and about 5% thereafter, so preventive measures should be instituted as soon as possible. Some specific risk factors for early recurrence include:

Older age
Evidence of blocked arteries (a history of coronary artery disease, peripheral artery disease, ischemic stroke, or TIA)
Hemorrhagic or embolic stroke
Diabetes
Alcoholism
Valvular heart disease
Atrial fibrillation

Prevention

The risk of stroke may be reduced with a healthy diet, control of high blood pressure, regular exercise, and by avoiding or quitting smoking. Follow your health care provider's recommendations for the treatment and prevention of heart disease. Forty percent of patients who have had a stroke or TIA will suffer a subsequent stroke within 5 years.

Quit Smoking

Smoking is a major risk factor for stroke. Patients should also avoid exposure to second-hand smoke. Many organizations recommend asking patients at every visit about smoking. Smoking is a chronic condition and often requires repeat therapy using more than one cessation technique.

Control Diabetes

People with diabetes should aim for fasting blood glucose levels of less than 110 mg/dl and hemoglobin A1C of less than 7%. Blood pressure goals should be 130/80 mm Hg or less.

Antiplatelet and Anticoagulant Medications for Preventing Stroke

Antiplatelet Drugs. Blood platelets are involved in blood clotting. Antiplatelets prevent clotting by blocking the activation of platelets. An antiplatelet drug -- most often aspirin -- is given within 48 hours of an ischemic stroke and continued in low doses as maintenance therapy. Some studies suggest that antiplatelet therapy can reduce the risk for a second stroke by 25%.

Primary Prevention (to prevent a stroke from occurring). People at high risk for heart disease should take a low-dose aspirin every day, unless they have medical reasons to avoid aspirin. (As an alternative to aspirin alone, your doctor may prescribe clopidogrel (Plavix) alone or aspirin plus extended release dipyridamole.) Aspirin may help to prevent strokes caused by blockage in the artery (ischemic stroke), but it may slightly increase the risk of strokes caused by bleeding in the brain (hemorrhagic stroke).

The American Heart Association recommends aspirin therapy (75 - 325 mg/day) for women over age 65 who are at risk for stroke. Women over age 65 who are at lower risk for stroke may consider taking aspirin every other day.
Aspirin therapy strictly to prevent strokes is not recommended for men who do not have heart disease. [For recommendations on aspirin therapy in the prevention of heart disease, see In- Depth Report #03: Coronary artery disease .]
Some younger patients with atrial fibrillation, or those for whom anticoagulants such as warfarin are not safe, are treated with aspirin or clopidogrel.

Secondary Prevention (to prevent another stroke after one has occurred). Aspirin combined with sustained release dipyridamole in a fixed-dose combination given twice daily is often prescribed to prevent another stroke. Aspirin is not recommended when uncontrolled hypertension is present. Clopidogrel may be used if aspirin cannot be taken but it is not better than aspirin. Combining aspirin and clopidogrel together does not have any more benefit and increases the risk for another stroke.

Anticoagulant Drugs. Warfarin (Coumadin) is the main anticoagulant (blood thinner) drug used to prevent strokes in high-risk patients with atrial fibrillation. Warfarin carries a risk for bleeding, but for most patients, warfarins benefits far outweigh its risks. The risk for bleeding is highest when warfarin therapy is first started, with higher doses, and with long periods of treatment. Patients at risk for bleeding are usually older and have a history of stomach bleeding and high blood pressure. It is important that patients who take warfarin have their blood checked regularly to make sure that it does not become too thin. Blood that is too thin increases the risk for bleeding, while blood that is too thick increases the risk for blood clots and stroke. Prothrombin time (PT) and international normalized ratio (INR) tests are used to monitor blood coagulation.

People with atrial fibrillation, who are generally considered candidates for warfarin therapy, often have one or more of the following characteristics:

History of blood clots to the lungs, stroke, or transient ischemic attack
Have a blood clot in one of their heart chambers
Significant valvular heart disease
High blood pressure
Diabetes, with age older than 65 years
Left atrium (one of the chambers of the heart) is enlarged
Coronary artery disease
Heart failure
Age 75 years or older

Diet and Weight Control

No randomized controlled trials have studied a direct relationship between diet and stroke. However, the relationship between diet and heart disease, unhealthy cholesterol and lipids, and high blood pressure seems to indicate that dietary recommendations for these disorders also may help prevent stroke. A healthy diet rich in fruits and vegetables and low in salt and saturated fats may significantly lower the risk for both ischemic and hemorrhagic stroke. For diet plans, the Mediterranean diet may be a particularly good choice for reducing the risk of stroke. [For more information, see In-Depth Report #43: Heart-healthy diet and In-Depth Report #14: High blood pressure.]

Some evidence suggests that diets rich in potassium may protect against stroke, mostly by reducing blood pressure but also possibly because of other mechanisms. Low potassium levels may increase the risk for stroke in certain people.

Salt Restriction. Although the effects of salt restriction are not entirely clear, a diet with less than or equal to 2,300 mg of sodium per day is recommended. (Restriction to 1,500 mg/day is recommended for middle-aged people and those with high blood pressure.)

Vitamins

Folic Acid and B Vitamins. Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. Researchers have been studying whether vitamin B supplements can reduce homocysteine levels and, consequently, heart disease risks.

Recent studies have indicated that while B vitamin supplements help lower homocysteine levels, they have no effect on heart disease outcomes. In studies, patients who have either recently had a heart attack or suffer from diabetes or heart disease show a similar number of heart attacks and strokes whether they took folic acid and B6 and B12 vitamins or received placebo. The vitamins seem to increase risks for patients who have a stent in their bodies. Some experts think that homocysteine may be a marker for heart disease rather than a cause of it. Newer approaches specifically designed for stroke patients are being evaluated.

Antioxidant Vitamins. The effects of antioxidant vitamins and carotenoids (vitamins C or E, or beta carotene) on stroke have been studied extensively. Most studies have found that these vitamins do not help protect against stroke.

Alcohol and Caffeine

Alcohol. Mild-to-moderate alcohol use (one to seven drinks a week) is associated with a significantly lower risk for ischemic stroke, although not hemorrhagic stroke. Heavy alcohol use, particularly a recent history of drinking, is associated with a higher risk of both ischemic and hemorrhagic stroke.

Coffee. In healthy people with normal blood pressure, drinking a couple of cups of coffee a day is unlikely to do any harm. Caffeine may actually have nerve-protecting properties that may help stroke survivors. Caffeine drinkers, however, might consider choosing tea, which may have beneficial nutrients, and people with existing hypertension should avoid caffeine altogether (since caffeine may increase the risk for stroke in this group).

Exercise

Exercise helps reduce the risk of atherosclerosis, which can help reduce the risk of stroke. Experts recommend at least 30 minutes of exercise on most, if not all, days of the week.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated, and controlled by medication, lifestyle changes, or a combination of both.

Reducing Blood Pressure

Reducing blood pressure is essential in stroke prevention. Lifestyle measures such as exercise, weight loss, and healthy diets are important for everyone. Drug therapy is recommended for people with hypertension who cannot control their blood pressure through lifestyle changes. Many different types of drugs are used to control blood pressure. They include ACE inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers, and diuretics. [For more information, see In-Depth Report #14: High blood pressure.]

Treatment Recommendations by Stage and Risk Groups
Risk Groups	Blood Pressure Stages (Systolic/Diastolic)
	Prehypertension (120 - 139/80 - 89)	Mild (Stage 1) Blood Pressure (140 - 159/90 - 99)	Moderate-to-Severe (Stage 2) Blood Pressure (Systolic pressure over 160 or diastolic pressure over 100)
Risk Group A Have no risk factors for heart disease.	Lifestyle changes only. (Exercise and dietary program with regular monitoring.)	Year trial of lifestyle changes only. If blood pressure is not lower at 1 year, add drug treatments.	Lifestyle changes and medications.
Risk Group B Have at least one risk factor for heart disease* (excluding diabetes) but have no target organ damage (such as in the kidneys, eyes, or heart, or existing heart disease).	Lifestyle changes only.	6-month trial of lifestyle changes only. If blood pressure is not lower at 6 months, add drug treatments. Medications considered for patients with multiple risk factors.	Lifestyle changes and medications.
Risk Group C Have diabetes with or without target organ damage and existing heart disease (with or without risk factors for heart disease).	Lifestyle changes and medications.	Lifestyle changes and medications.	Lifestyle changes and medications.

* Risk factors for heart disease include the following: family history of heart disease, smoking, unhealthy cholesterol and lipid levels, diabetes, being over 60 years old.

Lowering LDL and Raising HDL Cholesterol

In 2004, the National Cholesterol Education Program issued updated recommendations on how to control cholesterol levels. These guidelines emphasize that patients should lower their LDL (bad) cholesterol and recommend that more people take LDL-lowering medication. Lowering LDL cholesterol and raising HDL (good) cholesterol can significantly reduce the risks of heart disease, including stroke.

The doctor will start or consider medication, increase dosage of medication, or add new medication when:

LDL cholesterol is 190 mg/dL or higher.
LDL cholesterol is 160 mg/dL or higher AND patient has one risk factor for heart disease.
LDL cholesterol is 130 mg/dL or higher AND patient has either diabetes or two other risk factors for heart disease.
LDL cholesterol is 100 mg/dL or higher AND patient has heart disease or any other form of atherosclerosis. (If patient has diabetes, even without heart disease, medication may be considered for an LDL cholesterol of 100 mg/dL.)
LDL cholesterol is greater than 70 mg/dL AND patient has had a recent heart attack or has known heart disease along with diabetes, current cigarette smoking, poorly controlled high blood pressure, or the metabolic syndrome (high triglycerides, low HDL, and obesity).

Risk factors for heart disease include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Statins have become the most important LDL-lowering drugs. Brands include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). Research increasingly suggests that lowering LDL levels as much as possible is critical for preventing stroke and other heart disease problems. Analysis of data from many studies indicate that statins reduced the risk for heart problems by 60% and stroke by 17 - 25%.

Statins are proven to reduce the risk of ischemic stroke in people at increased risk for heart disease. (However, statins can increase the risk for the less-common hemorrhagic type of stroke.) Research suggests that they may also prevent stroke in patients without heart disease. However, current guidelines recommend that statins should be prescribed to patients without heart disease or high LDL (bad cholesterol) levels only if diabetes or other heart disease risk factors are also present.

Researchers are also investigating whether statins might be beneficial in preventing a second stroke in patients who have suffered a stroke or transient ischemic attack (TIA). Recent studies indicate that high-dose statin therapy may help reduce the risk of stroke recurrence and other heart events for patients who have had a prior stroke or TIA.

[For more information, see In-Depth Report #23: Cholesterol.]

Atrial Fibrillation and Its Treatments

As discussed previously, patients with chronic or recurrent atrial fibrillation are treated with aspirin or warfarin) to prevent clots from forming. Attempts to restore or maintain normal heart rhythm may be attempted with anti-arrhythmic drugs, cardioversion procedures, or surgery to remove the defective area. However, recurrent episodes of atrial fibrillation often occur. Simply controlling the heart rate is increasingly considered the preferable approach for many patients.

Diagnosis

Preventing a major stroke in people who experience transient ischemic attacks or small strokes requires determining the source of such attacks. A complete blood count, chest x-ray, and electrocardiogram are usually performed.

Examining the Carotid Artery. The doctor examines the carotid artery to determine if it is severely narrowed. If so, the patient is in danger of a major stroke. (The thickness of the carotid artery is also an important indicator for long-term risks for stroke, as well as heart disease and mortality rates in general.)

The doctor may use a number of approaches to determine the thickness of the artery.

Physical Examination. An important clue to a blocked carotid artery is a bruit. This is a whooshing sound caused by blood flow turbulence in the narrowed artery. A doctor may be able to hear a bruit using a stethoscope. Occasionally, even a patient can hear the sound. The presence of a bruit, however, is not necessarily a sign of an impending stroke, nor does the absence of a bruit indicate an unblocked artery.

Carotid Ultrasound or Duplex. Carotid ultrasound is a very valuable tool for measuring the width of the artery and how the blood flows through it. Severely blocked carotid arteries (a condition called carotid stenosis) may distort some measurements, so other tests may be required to confirm the results. Possible reasons to perform this test include:

When the doctor hears a bruit over the patient's carotid artery during the physical exam
After a patient has had a TIA or a stroke
To monitor patients who are known to have blockage (stenosis) in their carotid arteries

Screening of the general population with carotid duplex to identify those with asymptomatic carotid stenosis has not been studied in a randomized trial and is generally not recommended.

Carotid duplex is an ultrasound procedure performed to assess blood flow through the carotid artery to the brain. High-frequency sound waves are directed from a hand-held transducer probe to the area. These waves "echo" off the arterial structures and produce a two-dimensional image on a monitor, which will make obstructions or narrowing of the arteries visible.

General Guidelines for Diagnosing a Major Stroke

Identifying a Stroke Quickly. To save a patient's life, a fast diagnosis of both the presence and type of stroke is critical. Health professionals have devised different tests to help emergency workers quickly identify a person with stroke even before they reach the hospital. For example, an assessment tool called Face, Arms, Speech, Time (FAST) is highly accurate. It involves watching for the following signs:

(F)ACE. Ask the person to smile. Check to see if one side of the face droops.
(A)RMS. Ask the person to raise both arms. See if one arm drifts downward.
(S)PEECH. Ask the person to repeat a simple sentence. Check to see if words are slurred and if the sentence is repeated correctly.
(T)IME. If a person shows any of these symptoms, time is essential. It is important to get to the hospital as quickly as possible. Call 9-1-1. Act FAST.

Determining Ischemia Versus Hemorrhagic Stroke. Once a stroke has been identified, the next important step is to determine as quickly as possible whether it is hemorrhagic or ischemic. Clot-busting drug therapies can be life-saving for ischemic stroke patients, but they are effective only in the first 3 hours. In addition, they cause bleeding and can be lethal if the stroke is caused by a hemorrhage.

Ruling Out Other Disorders. In most cases of stroke, the diagnosis is evident although a number of conditions may cause similar symptoms. These include seizures, infections that cause mental confusion, syncope (fainting), hypoglycemia, and brain tumors.

Diagnostic Tests Used for Stroke and Risk Factors for Stroke

Computed Tomography. A computed tomography (CT) scan is essential for identifying or ruling out hemorrhagic strokes. The goal is to complete the CT examination and obtain and interpret the results within 45 minutes of arrival at the hospital. (An ultrasound technique called transcranial duplex sonography may be sensitive enough to differentiate between hemorrhagic and ischemic strokes if CT scans are not available.)

Certain factors suggest a hemorrhagic rather than ischemic stroke. They include specific symptoms (coma, vomiting, and severe headache), taking anticoagulants, very high systolic blood pressure, or high blood sugar levels in nondiabetics. However, such findings are not conclusive, and a CT scan or MRI is always needed.

Magnetic Resonance Imaging (MRI). MRI uses a magnetic field to provide 3-dimensional images of the brain. The MRI appears to work especially well for detecting ischemic stroke (stroke caused by blood clot) and is considered more accurate for detecting ischemic stroke within 3 hours of symptom onset (an important timeframe for delivering clotbuster drugs) in 46% of patients compared to only 7% for CT. Both MRI and CT perform similarly for detecting strokes caused by bleeding.

A computed tomography (CT) test uses x-ray images to take pictures of the skull and brain. Sometimes a dye is injected into a patients veins to enhance image contrast. Although research indicates that MRI is better in determining ischemic stroke, CT still may be useful in diagnosing hemorrhagic strokes. CT scans can generally be performed within a shorter period of time when needed to help make a quick decision about therapy. If it is performed first and the results are negative, patients who have suspicious signs or symptoms of stroke will often also receive an MRI soon after.

Transcranial Ultrasound. Transcranial duplex sonography can identify blockage in large arteries in stroke patients and monitor the effects of thrombolytic therapy.

Cerebral Angiography. Cerebral angiography is an invasive procedure that may be used for patients with TIAs who need surgery. It can also detect aneurysms and monitor thrombolytic therapy. It requires the insertion of a catheter into the groin, which is then threaded up through the arteries to the base of the carotid artery. At this point a dye is injected, and x-rays, CTs, or MRI scans determine the location and extent of the narrowing, or stenosis, of the artery. In people with TIAs the risk of stroke itself increases using this technique, particularly in elderly people with diabetes.

Magnetic Resonance Angiography (MRA) and Computerized Tomography Angiography. Magnetic resonance angiography and computerized tomography angiography are noninvasive ways of evaluating the carotid arteries and the arteries in the brain. In many situations, these tests can be used instead of cerebral angiography, an invasive procedure which carries a risk for bleeding in stroke.

Other Techniques. Other imaging tests, including positron-emission tomography (PET) and single photon-emission computed tomography (SPECT), may also help the doctor identify injuries caused by the stroke.

Heart Evaluation

Electrocardiogram (ECG). A heart evaluation using an electrocardiogram (ECG) is important in any patient with a stroke or suspected stroke. An ECG records the electrical current in the heart muscle.

Echocardiogram. An echocardiogram uses ultrasound to view the chambers and valves of the heart. It is generally useful for stroke patients to identify blood clots or risk factors for blood clots that can travel to the brain and cause stroke. There two are types:

Transthoracic echocardiograms (TTE) view the heart through the chest. It is noninvasive and is the standard approach.
Transesophageal echocardiogram (TEE) examines the heart using an ultrasound tube that the patient literally swallows and passes down the throat. It is uncomfortable and requires sedation. It is typically used to obtain more accurate images of the heart if a TTE has suggested abnormalities, such as atrial fibrillation or patent foramen ovale (PFO).

ABCD² Score

Patients who have a TIA are at increased risk for a major stroke in the days and weeks that follow. The ABCD² score is a tool that helps doctors predict short-term stroke risk following a TIA. The ABCD² score assigns points for various factors, including:

Age (over 60 years)
Blood pressure (greater or equal to 140/90 mm Hg)
Clinical features (weakness on one side of the body, speech impairment without weakness)
Duration of TIA symptoms (at least 60 minutes)
Diabetes

Based on the number of points, a doctor can identify whether a patient is at low, moderate, or high risk of having a stroke within 2 days after a TIA. Several 2006 and 2007 studies indicated that the ABCD² score works well in predicting stroke, and can help doctors better decide which patients need hospitalization and emergency care.

Other Tests

Blood Tests. Several blood tests may help predict the risk for a stroke and determine the severity and complications of an existing stroke.

Specific blood tests are important to determine clotting times, to check electrolytes (potassium, calcium, sodium), and to measure factors indicating liver or kidney problems. Kidney tests measure blood proteins that are filtered through the kidneys. These proteins include creatinine and blood urea nitrogen (BUN). A more recent type of kidney test measures the protein cystatin C. Recent research suggests that the cystatin C kidney test may be better at predicting cardiovascular risks in elderly patients.
Blood sugar (glucose) levels are measured. Hyperglycemia (high levels) may indicate a worse outcome for some strokes (although not hemorrhagic or lacunar strokes). Hypoglycemia (low levels) is a common complication of diabetes treatments, and its symptoms may mimic those of a stroke.

Examination of Spinal Fluid. If the CT scan is negative but the doctor still suspects a subarachnoid hemorrhagic stroke, a spinal tap may be performed. Spinal fluid containing significant amounts of blood will usually confirm a hemorrhagic stroke.

Managing a Stroke

Until recently, the treatment of stroke was restricted to basic life support at the time of the stroke and rehabilitation later. Now, however, treatments can be beneficial when administered as soon as possible after the onset of the stroke. It is critical to get to the hospital and be diagnosed as soon as possible. There are several steps in the initial assessment and management of a person with a stroke.

Get to the Hospital Immediately

If symptoms appear that suggest a stroke is occurring, calling 911 is critical (as opposed to calling the family doctor or trying to get the patient to the hospital by car). Receiving treatment early is essential in reducing the damage from a stroke.

Immediate Diagnosis and Evaluation of the Patient

Important diagnostic and evaluation steps are needed for the optimal treatment of a stroke patient:

Determining Whether the Stroke Is Ischemic or Hemorrhagic. As soon as the patient enters the hospital, diagnostic tests, particularly a CT scan, should be performed to determine whether the stroke is ischemic or hemorrhagic, and how extensive the stroke may be.

Determining The Need for Thrombolytic Drugs. If the stroke is ischemic, the next step is to determine if the patient would benefit from blood clot-busting drugs (called thrombolytics). The following factors are important for making this decision:

Time is critical in the decision-making process. Clot-buster drugs do not generally help if given more than 3 hours after stroke onset. Onset is when the patient first experiences any symptoms, even minor impairment. If the patient had a previous TIA that completely resolved before the stroke, however, onset is dated from when the more recent symptoms developed.
Risk factors for administering thrombolytic drugs include having recently taken a blood thinning drug, any accompanying medical or physical condition, and any recent event (such as surgery or injury) that may contribute to the condition.

Supportive Treatment for Acute Stroke

The patient should receive treatment to support basic life functions and to reduce stress, pain, and agitation. The following steps are also very important:

Maintaining Adequate Delivery of Oxygen. It is very important to maintain oxygen levels. In some cases, airway ventilation may be required. Supplemental oxygen may also be necessary for patients when tests suggest low blood levels of oxygen. Hyperbaric oxygen (oxygen administered under pressure) therapy for acute stroke has been evaluated some, but there is no strong evidence from high-quality clinical trials that hyperbaric oxygen is beneficial.

Managing Fever and Lowering Body Temperature (Hypothermia). Fever should be aggressively treated, since its presence predicts a poorer outlook. Some evidence suggests that hypothermia -- reducing body temperature to below normal -- might protect nerve cells in stroke patients. Cooling is done through special cooling blankets, ventilators, or infusion of cool fluids. Unfortunately, severe side effects occur with even moderate hypothermia (86 F, 30 C), which can include pneumonia, blood clotting disorders, heart rhythm disturbances, and others.

Maintain Electrolytes. Maintaining a healthy electrolyte balance (the ratio of sodium, calcium, and potassium in the body's fluids) is critical.

Managing Blood Pressure. Managing blood pressure is essential and complicated. Patients with stroke and pressures above 220 (systolic) or 120 (diastolic) should be treated. Lowering blood pressure too quickly can be dangerous, however, in patients with both ischemic and hemorrhagic strokes. In general, experts do not advise aggressively lowering elevated pressures below 220/120 mm Hg in patients unless they have other conditions, such as a heart attack, that require pressure-lowering treatments. In patients who need thrombolytic drugs, blood pressure should cautiously be lowered to 185/110 mm Hg. In most cases, blood pressure declines when these patients become stabilized.

Managing Increased Brain Pressure. Hospital staff should watch carefully for evidence of increased pressure on the brain, which is a frequent complication of hemorrhagic strokes. It can also occur a few days after ischemic strokes. Early symptoms of increased brain pressure are drowsiness, confusion, lethargy, weakness, and headache. Medications such as mannitol may be given during a stroke to reduce pressure or the risk for it.

Keeping the top of the body higher than the lower part, such as by elevating the head of the bed, can reduce pressure in the brain and is standard practice for patients with ischemic stroke. However, this practice also lowers blood pressure in general, which may be dangerous for patients with massive stroke.

Monitoring the Heart. Heart attack and arrhythmias are potential complications of ischemic stroke. Patients must be monitored using electrocardiographic tracings.

Controlling Glucose Levels. Elevated blood sugar (glucose) levels can occur with severe stroke and may be a marker of serious trouble. In general, it is advisable to lower glucose levels that are about 300 mg/dL, usually with insulin. It is not clear, however, if glucose-lowering treatments offer any advantage. Excessive lowering of glucose levels can have damaging effects on the brain. Studies are underway to determine the best approach.

Medications

Thrombolytics

Intravenous Thrombolytics. Clot-busting (thrombolytic) drugs break up existing blood clots. They are among the important treatments for heart attacks, and are now also used for ischemic (not hemorrhagic) stroke. While research has confirmed that early treatment with thrombolytics can greatly increase a stroke patient's chances for recovery, their use has been limited due to the short treatment window (within 3 hours of onset of stroke symptoms). The standard thrombolytic drugs are tissue plasminogen activators (t-PAs). They include alteplase (Activase) and reteplase (Retavase).

The following steps are critical before administering these clot-buster drugs:

Before the thrombolytic is given, a CT scan must first confirm that the stroke is not hemorrhagic. If the stroke is ischemic, a CT scan can also suggest if injuries are very extensive, which might affect the use of thrombolytics.
Thrombolytics must be administered within 3 hours of a stroke to have any effect. Best results are achieved if patients are treated with 90 minutes of a stroke. Unfortunately, most stroke patients arrive at the hospital more than 3 hours after an attack and therefore are not eligible for treatment. There is some evidence that t-PA administered withing 4 hours may also be effective, but more research needs to be conducted. These findings underscore the critical need for people to go to a hospital immediately if a stroke is suspected.

Thrombolytics carry a risk for hemorrhage, so they may not be appropriate for patients with existing risk factors for bleeding. They should not be used in patients who are experiencing seizures. The drug may be appropriate in more patients than previously thought, however, including older people, those with a history of stroke, and those with high blood pressure.

Intra-Arterial Thrombolytics. Researchers are investigating thrombolytics injected directly into an artery in the brain. Early studies suggest this approach may allow effective treatment up to 6 hours after a stroke and improve recovery in more patients. The risk for bleeding and hemorrhagic stroke is significantly increased, however.

Natural Defibronogenerating Drugs. These drugs deplete the amount of fibrinogen in blood, which in turn reduces the "stickiness" in blood. Such drugs include ancrod and batroxobin (Defibrase), both derived from the venom of poisonous snakes. They are being evaluated as a possible alternative to thrombolytics. Studies have not consistently shown benefit or a clearer role for these drugs in the treatment of acute stroke. As with all anti-clotting drugs, there is a higher risk for hemorrhage, but it appears to be slight.

Glycoprotein IIB/IIIa Inhibitors. Glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors are sometimes administered intravenously in the hospital and include abciximab (ReoPro, Centocor), eptifibatide (Integrilin), tirofiban (Aggrastat), lotrafiban, and lamifiban. They are being investigated alone or as additions to thrombolytic (clot-busting) drugs at the time of an acute stroke.

Antiplatelets and Anticoagulant Medications

Aspirin and clopidogrel (Plavix) are used for prevention of stroke. (For more information, see the Prevention section in this report.)

Anticoagulants thin blood and may be useful under certain circumstances. These medicines include:

Warfarin. The anticoagulant warfarin (Coumadin) may not work as well as aspirin in preventing a second stroke in people who have partial artery blockage in the brain (intracranial stenosis). Warfarin is, however, very important in high-risk patients with atrial fibrillation. It may be useful in other situations, such as patients with patent foramen ovale (PFO), those whose stroke followed a heart attack, or in high-risk patients who cannot take antiplatelet drugs.
Heparin. Intravenous heparin, a potent anti-platelet drug, has been used for ischemic stroke since 1941. Although many doctors continue to use it, five out of six major studies have reported no clear protective benefits for the use of standard heparin or heparin-like drugs compared to aspirin. These medicines also pose a much higher risk for hemorrhagic stroke. Experts now recommend heparins only for preventing thromboembolism in stroke patients at risk for this condition.
Direct Thrombin Inhibitors (DTIs). Direct thrombin inhibitors are a more recent group of anti-coagulants. The first DTI is hirudin, a natural substance derived from the saliva of leeches. New forms include argatroban (Novastan), bivalirudin (Angiomax), danaparoid (Orgaran), lepirudin (Refludan), and desirudin (Revasc).

All anti-clotting drugs carry a risk for bleeding and a slightly increased risk for hemorrhagic stroke.

Other Medications for Preventing a Recurring Stroke

It is important that patients control their high blood pressure and LDL (bad) cholesterol levels. Various drugs, such as statins, diuretics, and ACE inhibitors, can manage these conditions. People with diabetes should also maintain tight control of their blood sugar levels.

Drugs for Hemorrhagic Stroke

Calcium Channel Blockers. Early administration of calcium channel blockers, such as nimodipine (Nimotop), can improve functional outcome. One of the most common and serious dangers after a subarachnoid hemorrhagic stroke is spasm of the blood vessels near the ruptured site, which closes off oxygen to the brain. Calcium causes contraction of the smooth muscles of the blood vessels; calcium channel blockers are drugs that relax the blood vessels. The drugs work best if they are administered within 6 hours of the stroke. Calcium channel blockers are not useful for ischemic strokes, although they can be used in combinations with blood pressure lowering drugs to prevent them.

Surgery

Carotid Endarterectomy

Carotid endarterectomy is a surgical procedure that cleans out and opens up the narrowed carotid artery. It is used in patients at high risk for thrombotic ischemic strokes, which are caused by blockages in the internal carotid artery. It is also sometimes used after a stroke. In such cases, patients have reported improvements in vision, speech, swallowing, functioning of arms and legs, and general quality of life.

There is a risk of a heart attack or stroke from the procedure. Anyone undergoing this procedure should be sure their surgeon is experienced in recent techniques and that the medical center has complication rates of less than 6%. A 2000 study reported that older surgeons had a worse record than younger ones, possibly because they relied on residents or were less likely to adopt new procedures.

Procedure Description. The procedure generally is as follows:

The patient is usually given general anesthesia, although it has been reported that using local anesthetic is just as safe and reduces the cost of the procedure.
A bypass tube is put in place to transport blood around the blocked area during the procedure.
The surgeon scrapes away the plaque on the arterial wall.
The artery is sewn back together, and blood flow is restored.
The patient generally stays in the hospital for about 2 days. There is often a slight aching in the neck for about 2 weeks, and the patient should refrain as much as possible from turning the head during this period.

Endarterectomy is a surgical procedure that removes plaque material from the lining of an artery.

Click the icon to see an illustrated series detailing surgery for unblocking carotid arteries.

Determining Who Should Have Surgery. An important factor in deciding which patients with carotid stenosis are the best candidates for surgery is whether or not they are having symptoms.

Carotid stenosis may be identified when a carotid ultrasound is done to investigate findings on physical exam, such as a carotid bruit (a sound heard when a physician listens to the carotid artery in the neck with a stethoscope). If these patients are not having any symptoms, they have what is called asymptomatic carotid stenosis. If the carotid artery blockage is greater than 60%, surgery is considered an option since patients with this much blockage are at risk for a TIA or stroke in the future.

However, carotid artery surgery has a risk of complications (stroke, heart attack, death) during surgery or in the period soon afterwards. Large, high-quality studies have evaluated this problem and compared surgical treatment with medical treatment (usually aspirin or clopidogrel). Most of these studies have found a small benefit for performing surgery in patients 40 - 75 years of age, but only when performed by surgeons who have demonstrated that they do not have a high rate of serious complications when performing the surgery.

Patients with a history of stroke and evidence of severe stenosis (over 70% of the carotid artery is obstructed) can benefit from either carotid endarterectomy or carotid artery stenting. An experienced surgeon with a good track record is essential. Patients with mild stenosis (less than 50% obstruction) should not have endarterectomy; these patients do better with medications even if they have symptoms. For patients with moderate stenosis (50 - 69%), the decision to perform surgery needs to be determined on an individual basis.

Carotid endarterectomy is generally not recommended for patients with acute stroke.

Carotid Angioplasty and Stenting

Carotid angioplasty and stenting (CAS) is being investigated as a less-invasive alternative to carotid endarterectomy. It is based on the same principles as angiography done for heart disease.

An extremely thin catheter tube is inserted into an artery in the groin.
It is threaded through the circulatory system until it reaches the blocked area in the carotid artery.
The doctor either breaks up the clot or inflates a tiny balloon against the blood vessel walls (angioplasty).
After temporarily inflating the balloon, the doctor typically leaves a circular wire mesh (stent) inside the vessel to keep it open.

This procedure carries a risk for an embolic stroke and other complications. At this time, it is being used in some centers as an alternative to endarterectomy in patients who cannot undergo endarterectomy, especially for patients with severe stenosis (blockage greater than 70%) and high surgical risk. Several studies published in 2006 suggested that CAS should be used only for patients with these types of conditions.

Extracranial-Intracranial Bypass

Extracranial-intracranial (EC-IC) bypass has been under investigation for decades for ischemic stroke, but has had very mixed results, some extremely negative. With this procedure, a healthy artery in the scalp is rerouted to an area of the brain that was deprived of blood because of a blocked artery. This procedure is now sometimes used for patients with aneurysms. Some experts hope, however, that, in specific cases chosen via careful imaging and using the latest surgical techniques, EC-IC may prove to be helpful for some stroke patients.

Surgery for Preventing and Treating Hemorrhagic Strokes

Surgical Intervention of the Ruptured Aneurysms. In patients with subarachnoid hemorrhagic stroke, surgery to block off the aneurysm is usually recommended within a few days of the stroke. The standard procedure is to clip the aneurysm and stop bleeding. Alternative approaches are promising.

Surgical Intervention of Unruptured Aneurysms. With MRI of the brain being used in the evaluation and diagnosis of many neurologic disorders, many patients have cerebral aneurysms diagnosed incidentally. If an unruptured aneurysm is detected, patients should discuss all options with their doctor, including surgical repair. Unruptured aneurysms occur in 1 - 8% of the general population, however, and controversy exists over when to operate and on which patients.

In general, the decision rests on the size of the aneurysm, but uncertainty still exists. In one study, for example, the risk of rupture for aneurysms between 10 - 25 mm was quite low -- slightly less than 1% per year for both groups. Aneurysms over 25 mm, however, had a 6% chance of rupturing within a year. Studies have reported that in general, the risk for rupture is .05 - 2% a year, but recent evidence suggests that the risks may be even less.

Aneurysms can often cause symptoms, however, even if they do not rupture. Patients should discuss their particular risk factors carefully with their doctors. Individuals with arteriovenous malformation, a condition caused by abnormal associations between arteries and veins, should be monitored for the development of an aneurysm.

Clipping the Aneurysm. The standard surgical procedure for treating a ruptured aneurysm is to place a clip across the neck of the aneurysm, which blocks off bleeding. It is usually performed within the first 3 days. Getting to the aneurysm is often extremely difficult. Deep cooling of the body to stop circulation may be used to allow more time for the operation. Procedures that remove large portions of the bone in the skull are being developed to allow fast access. There is a relatively high risk for newly formed aneurysms, particularly after 9 years. Patients may want to discuss follow-up angiography to detect any new aneurysms 9 - 10 years after the procedure.

Transcatheter Embolization for Sealing off the Aneurysm. Transcatheter embolization is a new technique for ruptured and unruptured aneurysms that is proving to be effective, although it is still investigational. The surgeon threads a thin tube through the artery leading to the aneurysm through which materials are passed to plug or obstruct the aneurysm. In one version of this procedure, the following occurs:

A tiny platinum coil is inserted through the tube and positioned into the aneurysm.
An electric charge is passed through the coil to form blood clots.
In this case, blood clots benefit the patient by using the coil as a scaffold and sealing off the aneurysm.

Emergency Surgery for Hemorrhagic Strokes. Emergency surgery for a hemorrhagic stroke involves locating and removing large blood clots. In the past, such procedures had little effect on survival. Advances, however, are improving outcomes when surgery is performed very early.

Recovery

After a stroke, patients should take all necessary measures, including medications and lifestyle changes, to prevent another stroke. For those whose stroke was ischemic, aspirin, warfarin, or both will usually be prescribed.

Having a neurologist as the primary doctor after a stroke, rather than some other specialist or primary care doctor, significantly increases the chance for survival. Patients or their families should be persistent in requesting the best care possible during this important early period.

Receiving initial treatment at a stroke unit, instead of a general ward, plays a strong role for better long-term quality of life. Rehabilitation services aimed at patients living at home are also very effective in improving independence. Patients or their families should seek patient advocates or support associations to ensure they receive the right care.

Reducing the Risk for Non-Neurologic Complications after a Stroke

In addition to problems brought on by neurologic damage, stroke patients are also at risk for other serious problems that reduce their chances for survival. They include:

Blood clots in the legs (deep vein thrombosis)
Pulmonary embolism (a blood clot that travels to the lungs)
Pneumonia
Widespread infection
Heart problems
Urinary tract infections (a catheter is sometimes used in the first 48 hours after stroke to help with urinary retention, but if it is left in longer it can cause urinary tract infections)

Measures should be taken to monitor and treat patients for these important problems.

Candidates for Rehabilitation

In all, 90% of stroke survivors experience varying degrees of improvement after rehabilitation. The current cost-cutting climate generates pressure to send elderly patients who have had a stroke directly to a nursing home rather than a rehabilitation first. Not all patients, however, need or benefit from formal rehabilitation:

If the stroke is severe, intensive training would not be helpful.
If the stroke is mild, patients often improve without rehabilitation.

Positive factors that help predict good candidates for rehabilitation:

A patient should be able to sit up for at least an hour.
The patient should be able to learn and be aware.
Spasticity may be a good sign, because it indicates live nerve action.
Patients who are able to move their shoulders or fingers within the first 3 weeks after having a stroke are more likely to recover the use of their hands than patients who cannot perform these movements. The ability to feel light pressure on the affected hand, however, makes no difference for future hand movement.
Family members or close friends are available to be active participants in the rehabilitation process.

Factors that predict a poor response to rehabilitation:

Dysphagia (the inability to swallow) is associated with a higher mortality rate, possibly because of increased risk for infection and malnutrition. Dysphagic patients are given nutrition using a stomach tube or a feeding tube inserted down through the nose.
Incontinence.
The inability to recognize nonspeech sounds that occur right after a stroke.
A poor hand grip that is still present after 3 weeks is an indicator of severe problems.
Having had very severe seizures after the stroke.

Factors that do not rule out rehabilitation:

About 30% of patients experience aphasia (an impaired ability to speak). However, this disability does not necessarily affect the ability to think. Aphasia can also be temporary.
Although confusion is common among people who have had strokes, partial or even complete recovery is very possible.

Some Approaches to Rehabilitation

Physical therapy should be started as soon as the patient is stable, as early as 2 days after the stroke. Some patients will experience the fastest recovery in the first few days, but many will continue to improve for about 6 months or longer. Because stroke affects different parts of the brain, specific approaches to managing rehabilitation vary widely among individual patients:

Exercise program. Recent guidelines from the Veterans Administration recommend that patients get back on their feet as soon as possible to prevent deep vein thrombosis. Patients should try to walk at least 50 feet a day. Assisted devices or bracing are sometimes used to help support the legs. Treadmill exercises can be very helpful for patients with mild-to-moderate dysfunction. Exercise should be tailored to the stroke survivor's physical condition and can include aerobic, strength, flexibility, and neuromuscular (coordination and balance) activities.
Retraining muscles. Stretching and range-of-motion exercises are used to help treat spastic muscles. They can also help patients regain function in a paralyzed arm. Multiple techniques have been developed and studied. These include the Bilateral Arm Training with Rhythmic Auditory Cueing (BATRAC) technique, (which involves moving a bar with both arms in a sustained rhythmic pattern), and constraint-induced movement therapy (CIMT), which involves doing a series of repetitive exercises while the less functional arm is restrained.
Speech therapy and sign language. People who have had a stroke often have aphasia, a brain condition that makes it difficult to speak and understand language. Aphasia can come in many different forms. A person may be unable to speak at all, or just have difficulty saying the right word. Intense speech therapy after a stroke is important for recovery. Some experts recommend 9 hours a week of therapy for 3 months. A 2005 study indicated that a shorter period (3 hours a week for 10 days) also works well. Language skills improve the most when family and friends help reinforce the speech therapy lessons.
Swallowing training. Training patients and their caregivers regarding swallowing techniques, as well as safe and not safe foods and liquids, is essential for preventing aspiration (accidental sucking in of food or fluids into the airway).
Attention training. Problems with attention are very common after strokes. Direct retraining teaches patients to perform specific tasks using repetitive drills in response to certain stimuli. (For example, they are told to press a buzzer each time they hear a specific number.) A variant of this approach trains patients to relearn real-life skills, such as driving, carrying on a conversation, or other daily tasks.
Occupational training. Occupational therapy is important and improves daily living activities and social participation.

Drug Therapy for Rehabilitation

Drug therapy can sometimes help relieve specific effects of stroke:

Dantrolene (Dantrium), tizanidine (Zanaflex), and baclofen (Lioresel) are used to treat spasticity.
Heparin, a blood-thinning drug, is used to prevent blood clots from forming in the veins of the legs (thrombosis).
Some patients experience constant hiccups, which can be very serious. Chlorpromazine and baclofen are among the drugs used for this condition.
Studies have reported that dextroamphetamine or methylphenidate (Ritalin), an amphetamine used in attention deficit disorder, may help patients recover speech and motor skills when combined with physical therapy.

Certain drugs commonly taken for conditions associated with stroke may actually slow recovery. They include drugs used for high blood pressure, including clonidine and prazosin, anticonvulsant drugs, the antipsychotic drug haloperidol, and anti-anxiety drugs such as benzodiazepines.

Managing the Emotional Consequences

The Emotional State of the Patients. Strong motivation with the goal of independence after rehabilitation is important for recovery. Unfortunately, depression is very common after a stroke, both as a direct and indirect result of the stroke:

Strokes that affect the right hemisphere in the brain increase the risk for depression.
Patients can become depressed by the changes in their ability to function.
A peculiar stroke-induced condition, known as post-stroke crying or neurologic emotionalism, is a neurologic not a psychologic disorder.

If depression is prolonged, it can interfere with recovery. One study showed that people who suffered strokes and became depressed were three times more likely to die within 10 years than stroke victims who were not depressed. There is a significantly increased risk of suicide in patients with stroke, especially in women and those under age 60.

Antidepressants, particularly fluoxetine (Prozac) and similar so-called SSRI drugs, have been beneficial in relieving post-stroke crying as well as improving recovery in general and mood in particular. Antidepressants may also help restore mental abilities.

Some doctors also recommend tricyclic antidepressants, which include amitriptyline (Elavil) and nortriptyline (Pamelor). In one study nortriptyline (Pamelor) not only improved mood but also had positive effects on mental functioning, suggesting perhaps that some dementia associated with stroke may actually be due to depression. Tricyclics may also be useful for neurologic emotionalism.

Anxiety disorder is also common and debilitating. Some research indicates that many patients suffer from feelings identical to post-traumatic stress syndrome. The two disorders often overlap, but drug treatments for each differ and may offset the other.

Many drugs for psychologic disorders affect the central nervous system and can delay rehabilitation. Skilled professional help is needed to determine the most effective and safest treatments.

The Emotional State of the Caregiver. The caregiver's emotions and responses to the patient are critical. Patients do worse when caregivers are depressed, overprotective, or not knowledgeable about the stroke. Unfortunately, in one study, over half of the caregivers themselves were depressed, particularly if the stroke victims were left with dementia or abnormal behavior.

Resources

www.strokeassociation.org -- American Stroke Association
www.americanheart.org -- American Heart Association
www.stroke.org -- National Stroke Association
www.ninds.nih.gov -- National Institute of Neurological Disorders and Stroke
www.aphasia.org -- National Aphasia Association
www.aan.com -- American Academy of Neurology
www.strokecenter.org/trials -- Stroke Trials Directory

References

Adams HP Jr, del Zoppo G, Alberts MJ, Bhatt DL, Brass L, Furlan A, et al. Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: The American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists. Circulation. 2007 May 22;115(20):e478-534.

Aguilar MI, Hart R, Pearce LA. Oral anticoagulants versus antiplatelet therapy for preventing stroke in patients with non-valvular atrial fibrillation and no history of stroke or transient ischemic attacks. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD006186.

Amarenco P, Goldstein LB, Szarek M, Sillesen H, Rudolph AE, Callahan A 3rd, et al. Effects of intense low-density lipoprotein cholesterol reduction in patients with stroke or transient ischemic attack: the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial. Stroke. 2007 Dec;38(12):3198-204. Epub 2007 Oct 25.

Carson S, McDonagh M, Russman B, Helfand M. Hyperbaric oxygen therapy for stroke: a systematic review of the evidence. Clin Rehabil. 2005 Dec;19(8):819-33.

Chalela JA, Kidwell CS, Nentwich LM, Luby M, Butman JA, Demchuk AM, et al. Magnetic resonance imaging and computed tomography in emergency assessment of patients with suspected acute stroke: a prospective comparison. Lancet. 2007 Jan 27;369(9558):293-8.

Chaturvedi S, Bruno A, Feasby T, Holloway R, Benavente O, Cohen SN, et al. Carotid endarterectomy -- an evidence-based review: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology. 2005;65:794801.

Dickerson LM, Carek PJ, Quattlebaum RG. Prevention of recurrent ischemic stroke. Am Fam Physician. 2007 Aug 1;76(3):382-8.

Dorhout Mees SM, Rinkel GJ, Feigin VL, Algra A, van den Bergh WM, Vermeulen M, et al. Calcium antagonists for aneurysmal subarachnoid haemorrhage. Cochrane Database Syst Rev. 2007 Jul 18;(3):CD000277.

Ford GA, Choy AM, Deedwania P, Karalis DG, Lindholm CJ, Pluta W, et al. Direct thrombin inhibition and stroke prevention in elderly patients with atrial fibrillation: experience from the SPORTIF III and V Trials. Stroke. 2007 Nov;38(11):2965-71. Epub 2007 Sep 20.

Goldstein LB. Prevention and management of stroke. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Saunders;2007:chap 58.

Goldstein LB, Adams R, Alberts MJ, Appel LJ, Brass LM, Bushnell CD, et al. Primary prevention of ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council: cosponsored by the Atherosclerotic Peripheral Vascular Disease Interdisciplinary Working Group; Cardiovascular Nursing Council; Clinical Cardiology Council; Nutrition, Physical Activity, and Metabolism Council; and the Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation. 2006 Jun 20;113(24):e873-923.

Goldstein LB, Amarenco P, Szarek M, Callahan A 3rd, Hennerici M, Sillesen H, et al. Hemorrhagic stroke in the Stroke Prevention by Aggressive Reduction in Cholesterol Levels study. Neurology. 2007 Dec 12 [Epub ahead of print]

Hart RG, Pearce LA, Aguilar MI. Meta-analysis: antithrombotic therapy to prevent stroke in patients who have nonvalvular atrial fibrillation. Ann Intern Med. 2007 Jun 19;146(12):857-67.

Hartmann A, Mast H, Choi JH, Stapf C, Mohr JP.Treatment of arteriovenous malformations of the brain. Curr Neurol Neurosci Rep. 2007 Jan;7(1):28-34.

Hennerici MG, Kay R, Bogousslavsky J, Lenzi GL, Verstraete M, Orgogozo JM; ESTAT investigators. Intravenous ancrod for acute ischaemic stroke in the European Stroke Treatment with Ancrod Trial: a randomised controlled trial. Lancet. 2006 Nov 25;368(9550):1871-8.

Kurth T, Gaziano JM, Cook NR, Logroscino G, Diener HC, Buring JE. Migraine and risk of cardiovascular disease in women. JAMA. 2006 Jul 19;296(3):283-91.

Legg L, Drummond A, Leonardi-Bee J, Gladman JR, Corr S, Donkervoort M, et al. Occupational therapy for patients with problems in personal activities of daily living after stroke: systematic review of randomised trials. BMJ. 2007 Nov 3;335(7626):922. Epub 2007 Sep 27.

Mandava P, Kent TA. Intra-arterial therapies for acute ischemic stroke. Neurology. 2007 Jun 12;68(24):2132-9.

Mann DL. Management of heart failure patients with reduced ejection fraction. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Saunders;2007:chap 25.

Mas JL, Chatellier G, Beyssen B, Branchereau A, Moulin T, Becquemin JP, et al. Endarterectomy versus stenting in patients with symptomatic severe carotidstenosis. N Engl J Med. 2006 Oct 19;355(16):1660-71.

Mosca L, Banka CL, Benjamin EJ, Berra K, Bushnell C, Dolor RJ, et al. Evidence-based guidelines for cardiovascular disease prevention in women: 2007 update. Circulation. 2007 Mar 20;115(11):1481-501.

Olgin JE and Zipes DP. Specific arrhythmias: diagnosis and treatment. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Saunders;2007:chap 35.

O'Regan C, Wu P, Arora P, Perri D, Mills EJ. Statin therapy in stroke prevention: a meta-analysis involving 121,000 patients. Am J Med. 2008 Jan;121(1):24-33.

Ringleb PA, Chatellier G, Hacke W, Favre JP, Bartoli JM, Eckstein HH, et al. Safety of endovascular treatment of carotid artery stenosis compared with surgical treatment: a meta-analysis. J Vasc Surg. 2008 Feb;47(2):350-5.

Rosamond W, Flegal K, Furie K, Go A, Greenlund K, Haase N, et al. Heart disease and stroke statistics -- 2008 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2008 Jan 29;117(4):e25-146. Epub 2007 Dec 17.

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SPACE Collaborative Group; Ringleb PA, Allenberg J, Bruckmann H, Eckstein HH, Fraedrich G, et al. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: a randomised non-inferiority trial. Lancet. 2006 Oct 7;368(9543):1239-47.

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Wang X, Qin X, Demirtas H, Li J, Mao G, Huo Y, et al. Efficacy of folic acid supplementation in stroke prevention: a meta-analysis. Lancet. 2007 Jun 2;369(9576):1876-82.

Wolf SL, Winstein CJ, Miller JP, Taub E, Uswatte G, Morris D, et al. Effect of constraint-induced movement therapy on upper extremity function 3 to 9months after stroke: the EXCITE randomized clinical trial. JAMA. 2006 Nov 1;296(17):2095-104.

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Review Date: 4/17/2008
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

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Health Topics A-Z

Stroke

Highlights

Introduction

Ischemic Stroke

Transient Ischemic Attacks (TIAs)

Hemorrhagic Stroke

Symptoms

Symptoms of TIAs and Early Ischemic Stroke

Symptoms of Hemorrhagic Stroke

Risk Factors

Age

Gender

Ethnicity

Presence of Other Vascular Disease

Abnormal Blood Pressure

Heart Abnormalities Causing Traveling Blood Clots (Embolisms)

Smoking

Diabetes and Insulin Resistance

Obesity and Metabolic Syndrome

Cholesterol and Other Lipids

Genetic and Inborn Factors

Mental and Emotional Factors

Migraine and Associated Risk Factors

Infections and Inflammation

Peripheral Artery Disease

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)

Other Medical or Physical Conditions Associated with a Higher Risk for Stroke

Other Factors Associated with Stroke

Prognosis

The Severity of an Ischemic Versus Hemorrhagic Stroke

Long Term Complications and Deficits

Factors that Affect Quality of Life in Survivors

Factors Affecting Recurrence

Prevention

Quit Smoking

Control Diabetes

Antiplatelet and Anticoagulant Medications for Preventing Stroke

Diet and Weight Control

Vitamins

Alcohol and Caffeine

Exercise

Reducing Blood Pressure

Treatment Recommendations by Stage and Risk Groups

Lowering LDL and Raising HDL Cholesterol

Atrial Fibrillation and Its Treatments

Diagnosis

General Guidelines for Diagnosing a Major Stroke

Diagnostic Tests Used for Stroke and Risk Factors for Stroke

Heart Evaluation

ABCD2 Score

Other Tests

Managing a Stroke

Get to the Hospital Immediately

Immediate Diagnosis and Evaluation of the Patient

Supportive Treatment for Acute Stroke

Medications

Thrombolytics

Antiplatelets and Anticoagulant Medications

Other Medications for Preventing a Recurring Stroke

Drugs for Hemorrhagic Stroke

Surgery

Carotid Endarterectomy

Carotid Angioplasty and Stenting

Extracranial-Intracranial Bypass

Surgery for Preventing and Treating Hemorrhagic Strokes

Recovery

Reducing the Risk for Non-Neurologic Complications after a Stroke

Candidates for Rehabilitation

Some Approaches to Rehabilitation

Drug Therapy for Rehabilitation

Managing the Emotional Consequences

Resources

References

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