Stroke & Brain

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Stroke & the Brain Also called: Embolic Stroke, Ischemic Stroke, CVA, Cerebrovascular Accident, Brain Attack, Thrombotic Stroke, Hemorrhagic Stroke Summary A stroke is a potentially life-threatening event in which part of the brain is deprived of adequate oxygen. Also known as a cerebrovascular accident (CVA), a stroke can be very dangerous. Each year, approximately 700,000 strokes occur in the United States, of which 500,000 are new (first-time) strokes, according to the Centers for Disease Control and Prevention . More than 160,000 Americans die every year from strokes. There are two types of strokes. An ischemic stroke occurs when the blood supply to the brain is interrupted, usually by a blood clot. The second kind of stroke is a hemorrhagic stroke, which occurs when there is bleeding into or around the brain. Almost 90 percent of all strokes are ischemic, while the remainder are hemorrhagic, according to the American Heart Association . When blood flow to the brain stops, brain cells begin to die because they do not receive the oxygen and nutrients they need to survive. Survival and potential recovery from a stroke depend on quick access to medical care. In recent years, the mortality rate from strokes has fallen, thanks to advances in immediate stroke treatment.

Transcript of Stroke & Brain

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Stroke & the Brain

Also called: Embolic Stroke, Ischemic Stroke, CVA, Cerebrovascular Accident, Brain Attack, Thrombotic Stroke, Hemorrhagic Stroke

SummaryA stroke is a potentially life-threatening event in which part of the brain is deprived of adequate oxygen. Also known as a cerebrovascular accident (CVA), a stroke can be very dangerous. Each year, approximately 700,000 strokes occur in the United States, of which 500,000 are new (first-time) strokes, according to the Centers for Disease Control and Prevention . More than 160,000 Americans die every year from strokes.

There are two types of strokes. An ischemic stroke occurs when the blood supply to the brain is interrupted, usually by a blood clot. The second kind of stroke is a hemorrhagic stroke, which occurs when there is bleeding into or around the brain. Almost 90 percent of all strokes are ischemic, while the remainder are hemorrhagic, according to the American Heart Association .

When blood flow to the brain stops, brain cells begin to die because they do not receive the oxygen and nutrients they need to survive. Survival and potential recovery from a stroke depend on quick access to medical care. In recent years, the mortality rate from strokes has fallen, thanks to advances in immediate stroke treatment.

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Symptoms of a stroke can vary depending on the type of stroke that has occurred. However, the National Institute of Neurological Disorders and Stroke (NINDS) lists several major general signs of stroke. All of these symptoms appear suddenly:

Numbness or weakness of the face, arms or legs Confusion Trouble speaking or understanding language (aphasia) Trouble seeing in one or both eyes (vision loss) Difficulty walking Dizziness Loss of balance and coordination (ataxia) Severe headache (without a known cause)

When a patient shows symptoms of a stroke, the physician will promptly evaluate the patient’s medical history and immediately perform brain imaging tests such as a computed axial tomography (CAT) scan. Prompt treatment focuses on re-establishing blood flow to the brain and stabilizing the patient. Medications, surgery and rehabilitation (e.g. physical therapy) may be part of the overall treatment process.

There are many different risk factors associated with strokes. These include advanced age, a family history of strokes, smoking, high blood pressure, obesity, and a history of transient ischemic attacks, sometimes called "mini-strokes." Preventative measures do not fully protect an individual against having a stroke but can go far to reduce the risks of such an event. These may include smoking cessation, blood pressure control, regular exercise and a healthy diet.

About stroke

A stroke is a potentially life-threatening event that occurs when part of the brain is deprived of adequate oxygen. Also known as a cerebrovascular accident (CVA) or a “brain attack,” a stroke occurs when a blood vessel in the brain bursts or becomes clogged by a blood clot or other materials. Thie blockage of brain blood vessels prevents oxygen and nutrients from getting to nerve cells in the affected area of the brain. Without adequate oxygen these nerve cells typically die within minutes, and the area of the body that they control can cease to function. This damage can be permanent, especially if the patient is not immediately treated.

Each year, approximately 700,000 strokes occur in the United States, of which 500,000 are new (first-time) strokes, according to the Centers for Disease Control and Prevention . More than 160,000 Americans die every year from strokes. Strokes are the third leading cause of death in the United States, behind heart disease and cancer, according to the National Stroke Association. 

Immediate response to a stroke can help prevent damage, but a stroke left untreated for too long may result in irreversible nerve and tissue damage that can cause symptoms such as a permanent loss of speech or paralysis. It can even lead to death. Damage to the brain due to a stroke can result in disabilities throughout the body that may be mild to severe. Complications associated with strokes include:

Emotional problems. Some stroke patients have difficulty controlling their emotions and may express inappropriate emotions. Others may become depressed. People may cry easily or undergo sudden mood swings for no apparent reason. This is known as emotional lability.

Paralysis and weakness. Strokes may cause complete paralysis on one side of the body (hemiplegia) or weakness that appears on one side of the body (hemiparesis).

Problems with language involving speaking and understanding (aphasia) and problems with thinking. Stroke survivors may have trouble initiating and/or understanding speech.

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They may also struggle with cognitive skills such as attentiveness, awareness, judgment, learning, memory and thinking.

Sensation and perception changes. Patients who have had a stroke may experience numbness or other unusual sensations. Pain or numbness may be experienced in the hands and feet, and may worsen with movement or temperature changes, particularly at lower temperatures. Patients may also find that their perception of everyday objects has changed due to an impaired ability to see, touch, move or think.

Difficulties chewing and swallowing (dysphagia). A stroke may weaken muscles on one or both sides of the mouth, leading to difficulty with chewing and swallowing.

The diagnosis, treatment and prevention of strokes are complicated because there are two major distinct types of strokes – ischemic and hemorrhagic strokes – and they are distinctly different. An ischemic stroke involves a clot or blockage in an artery, while a hemorrhagic stroke involves bleeding inside or around the brain. Of the two forms of stroke, hemorrhagic stroke generally poses more immediate danger because increased pressure on the brain due to bleeding can cause death.

Yet, people who survive a stroke tend to recover more fully if the stroke was hemorrhagic rather than ischemic. This is because the damage in a hemorrhagic stroke is caused by pressure on the brain and may be reversible once the pressure is relieved. In contrast, the damage associated with an ischemic stroke is a result of blockage in an artery that results in death of the affected brain tissues. When this occurs recovery is more difficult.  

In recent years, there have been advances in the immediate care and treatment of strokes as physicians have become better at diagnosing what type of stroke has occurred and moving quickly to treat it. This has resulted in higher survival rates, and a corresponding higher rate of hospitalization from strokes as more people survive their strokes.

Types and differences of strokes

There are two major types of strokes:

Ischemic stroke. An ischemic stroke is due to restriction of blood flow to the brain. It usually involves a blood clot or blockage in an artery (blood vessel that carries blood away from the heart) in the brain. The majority – almost 90 percent – of all strokes that occur in the United States are ischemic strokes, according to the American Heart Association . There are two kinds of ischemic strokes:

Thrombotic strokes. Stroke due to blood vessel blockage that begins in the brain. A thrombotic stroke can occur when a blood clot (thrombus) forms in an artery in the brain, which can result from a hardening of the arteries (atherosclerosis). Most ischemic strokes are thrombotic.

Embolic strokes. Stroke due to blood vessel blockage (embolism) that travels through the bloodstream to the brain from another part of the body. Embolic strokes are frequently the result of blood pooling in the upper chambers of the heart (the atria) in people who have abnormal heart rhythms (arrhythmias), such as atrial fibrillation. In addition, blood clots may form in the area due to a weakened heart muscle, or may travel from a vein to the heart (e.g., due to a hole in the wall between the right and left atria [atrial septal defect]). The swelling of blood flow in the heart raises the risk of a blood clot forming and of it traveling into the carotid arteries (the arteries that carry blood from the heart to the brain).

Hemorrhagic stroke. A hemorrhagic stroke is caused by excessive bleeding (hemorrhaging) within or around the brain. In addition, this loss of blood supply from cells in the brain can prevent the cells from properly functioning. Blood that accumulates may pressure surrounding brain tissue, which can lead to further interference with brain activity. There are two kinds of hemorrhagic strokes:

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Cerebral hemorrhage. Bleeding within the brain. This may occur when a defective artery within the brain bursts, which is often a complication of high blood pressure. Blood that leaks from a blood vessel in the brain can accumulate over a matter of minutes or hours. Other causes of cerebral hemorrhage include cerebral aneurysms (blood-filled pouches that balloon out from weak spots in an arterial wall), arteriovenous malformations and brain tumors. Cerebral hemorrhage is the most common type of hemorrhagic stroke, accounting for just under 10 percent of all strokes in the United States, according to the American Heart Association.

Subarachnoid hemorrhage. Bleeding around the brain. This occurs when a blood vessel on the brain’s surface ruptures and bleeds into the space between the brain and skull, but not into the brain itself. It may result from various conditions, including a ruptured cerebral aneurysm or a head injury.

In addition to ischemic and hemorrhagic strokes, some people may experience a transient ischemic attack (TIA). This is a brief, temporary interruption in blood flow to the brain and is often called a “mini-stroke.” TIAs often precede certain types of ischemic strokes (thrombotic strokes). The National Stroke Association estimates that 40 percent of people who have had a TIA will have a major stroke at some point in the future. Despite the danger associated with TIAs, many people do not seek treatment for TIAs.

Risk factors and causes of stroke

Strokes can have a variety of causes, depending on the type of stroke involved.

Ischemic strokes result from a restriction of blood flow to the brain. Blood clots are the most common cause of arterial blockage, but blood vessel blockage can also result from a narrowing of the arteries (stenosis), which often results from a buildup of material in the lining of an artery (atherosclerosis).

Hemorrhagic strokes result from bleeding within or around the brain. This may be caused by the bursting of an artery within the brain. This can occur when a weak spot on an artery wall expands (cerebral aneurysm) or when artery walls begin to lose elasticity, leaving them brittle, thin and prone to cracks.

Various risk factors are associated with strokes. They include:

History of transient ischemic attacks (TIA). These “mini-strokes” are caused by brief, temporary interruptions in blood flow to the brain. People who experience a TIA are 10 times more likely to have a stroke than their counterparts who do not experience a TIA. A stroke may sometimes occur as soon as two days after a TIA.

Advanced age. While strokes can strike at any age, nearly three-quarters of strokes occur in people older than 65, according to the Centers for Disease Control and Prevention (CDC). The risk of a stroke doubles with each decade over the age of 55. Young people are most likely to have strokes resulting from cocaine use, high blood pressure , a traumatic head injury, carotid artery dissection or other causes.

Gender. At younger ages, men are more likely to experience and die from a stroke, although overall more women are killed by stroke, perhaps because women tend to live longer. Among older people, the incidence of stroke is roughly equal.

High blood pressure (hypertension). Studies have shown that people with hypertension have a risk of stroke that is 4 to 6 times higher than it is for people without hypertension. Hypertension is considered an important risk factor for stroke because it usually presents no symptoms or warning signs. Studies have shown that patients with a systolic/diastolic blood pressure of less than 120/80 mmHg have about half the lifetime risk of stroke compared to people with high blood pressure.

Coronary artery disease (CAD) (narrowing of the arteries that supply blood to the heart). There is a strong correlation between CAD and ischemic stroke because both are caused by the same underlying process, atherosclerosis. Atherosclerosis occurs when arteries become obstructed by plaque deposits in the lining of an artery.

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Atrial fibrillation. This heart rhythm disorder can cause the blood to clot. If these blood clots travel from the heart up into the brain, a stroke may occur. The disorder is associated with 15 percent of all strokes, according to the CDC.

Diabetes. People with diabetes have two to four times the risk of stroke compared to people who do not have the illness, according to the CDC. Having diabetes also appears to worsen the outcome of a stroke in many cases.

Smoking. Smoking doubles a person’s risk for ischemic stroke, according to the CDC. Smoking promotes atherosclerosis, in which plaque builds up on the walls of arteries. In addition, smoking increases the levels of certain blood clotting factors, such as fibrinogen. Nicotine also raises blood pressure, and the carbon monoxide in cigarette smoke (if inhaled) reduces the amount of oxygen that blood can carry to the brain.

Family history of stroke. The risk of stroke increases if a person's parents, grandparents, sisters or brothers have had a stroke.

Low levels of HDL (“good”) cholesterol and high levels of LDL (“bad”) cholesterol. Poor levels of good and bad cholesterol can lead to atherosclerosis, which significantly raises the risk of stroke.

Obesity. A body mass index (BMI) of 30 or greater (indicating a person is obese) increases the risk of stroke. BMI is usually related to the amount of body fat.

Lack of exercise. Not maintaining a moderate level of physical activity can lead to obesity, which increases the risk of stroke.

carotid artery dissection. A tear in the inner lining of the carotid artery, creating a space through which blood could leak, causing a stroke.

Excessive use of alcohol. This can lead to an increase in blood pressure, which increases the risk of stroke.

Illegal drug use. Drugs associated with an increased risk of stroke include cocaine, heroin and amphetamines.

Head injury, neck injury. Physical trauma to these areas can damage blood vessels and increase the risk of stroke.

Birth control pills and hormone therapy have been linked to an increased risk of stroke. Taking birth control pills increases the risk of stroke, especially for women who smoke and are over the age of 35. Low-dose birth control pills appear to carry a lower risk for stroke. Data from large studies have also demonstrated that hormone replacement therapy, using either estrogen alone or estrogen plus synthetic progesterone, raises the risk of stroke among healthy postmenopausal women.

Prior stroke or heart attack. Living in the southeastern United States. For several decades, the southeastern United

States has had the highest stroke mortality rate in the nation, according to the CDC. The reason for this increased risk factor remains unknown.

Undergoing catheter-based procedures. People who have surgeries that involve placing certain types of catheters (small, flexible tubes) into the heart have a higher risk of blood clot formation.

Other possible contributors to the risk of stroke include:

Sleep apnea. A condition in which breathing involuntarily stops and starts during sleep. Interruptions in oxygen to the heart and brain can significantly increase a person’s risk of heart disease, high blood pressure and stroke.

Atrial flutter. A type of atrial tachycardia, which is an unusually fast heart rhythm that originates in the upper chambers of the heart (atria). Atrial flutter is characterized by a very rapid but regular electrical signal in the atria, which causes a very rapid heartbeat.

Depression. Although the exact mechanism is not clearly understood, studies continue to show an association between chronic depressive symptoms and increased risk of stroke.

Acute inflammation in the body. Studies have shown that people that test positive on a blood test for certain proteins that indicate acute infection have an increased risk of stroke. The test used is called a C-reactive protein test. A positive result may indicate the presence of certain inflammatory conditions or diseases (e.g., rheumatoid arthritis, lupus).

Although stroke affects all races and ethnicities, African Americans have the greatest risk of stroke. This includes a higher likelihood of stroke at an earlier age and greater risk of overall mortality.

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Medical researchers do not completely understand why African Americans have an increased risk of stroke. Some studies have suggested that racism and poverty may play a role. In addition, African Americans are more likely to have medical risk factors (e.g., diabetes, high blood pressure, sickle cell anemia, smoking, obesity) known to be closely associated with stroke.

Signs and symptoms of stroke

Strokes injure the brain, which makes it less likely that patients will recognize what is happening to them as a stroke unfolds. In addition, bystanders also may not be aware of what is happening. For this reason, people of all ages are urged to learn about the signs and symptoms of a stroke.

Prompt diagnosis and treatment of a stroke by a medical professional is crucial to limiting the potential damage associated with strokes. Strokes that are left untreated for too long can result in a loss of consciousness and death. It is important that anyone experiencing stroke-like symptoms seek emergency medical care , regardless of the degree or duration of symptoms.

Symptoms can vary according to the type of stroke experienced. However, the National Institute of Neurological Disorders and Stroke (NINDS) lists several major general signs of strokes. All of these symptoms appear suddenly:

Numbness or weakness of the face, arms or legs Confusion Trouble speaking or understanding language (aphasia) Trouble seeing in one or both eyes (vision loss) Difficulty walking Dizziness Loss of balance and coordination (ataxia) Severe headache (without a known cause) Paralysis of part of the body

The onset of symptoms of ischemic strokes may vary, depending on the subtype of ischemic stroke experienced. For example, the symptoms of an embolic stroke tend to appear suddenly, whereas the symptoms of a thrombotic stroke develop more gradually. The symptoms of both subtypes may include:

Blindness in one eye or hearing problems in one ear Confusion Dizziness or loss of balance/coordination Nausea and/or vomiting Numbness or weakness on only one side of the body Seizures Severe (and blinding) headache similar to a migraine Trouble speaking or understanding speech

Hemorrhagic strokes tend to produce symptoms that appear suddenly and then continue to worsen. Both subtypes (cerebral hemorrhage and subarachnoid hemorrhage) produce similar symptoms. These symptoms include:

Confusion Nausea and/or vomiting Pain upon looking at or into a light Painful or stiff neck Severe headache

Transient ischemic attacks (TIA), or so-called "mini-strokes," occur when the blood flow to the brain is briefly and temporarily restricted. The symptoms of a TIA are similar to an ischemic

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stroke, but generally milder. Although TIAs were once considered relatively harmless, new studies have shown that TIAs can result in long-term brain damage.

In some cases, strokes may occur with no obvious symptoms. These are referred to as silent strokes. It is estimated that about one-third of elderly people in the United States may have had a silent stroke, which often damages their cognitive abilities. People who experience silent strokes have twice the risk of developing dementia.

Diagnosis methods for stroke

When a patient has signs or symptoms of a stroke, a physician will promptly evaluate the patient’s medical history and obtain brain imaging tests such as a computed axial tomography (CAT) scan. The CAT scan can help the physician determine whether the patient is having a cerebral hemorrhage or an ischemic stroke caused by cerebral ischemia. This information determines the course of emergency treatment. The CAT scan may also help a physician locate the exact position of the brain damage.

Once the patient is stabilized, a complete evaluation of a patient who has had a stroke can take several days. Tests that may be performed during this time may include:

Physical examination, during which functioning of the carotid arteries (the arteries that carry blood from the heart to the brain) will be examined with a stethoscope. If a physician hears an abnormal sound (a carotid bruit), it may indicate atherosclerosis (hardening of the arteries) or carotid artery disease – conditions that increase the risk of stroke.

A carotid ultrasound is a painless technique that uses high-frequency sound waves to identify the presence of plaque in the carotid arteries.

Magnetic resonance angiography (MRA) is a diagnostic imaging test used to assess the degree of blockage in arteries in and around the brain. The MRA is a variation of the magnetic resonance imaging (MRI) scan, which is also very important in diagnosing a stroke. MRA is used specifically for the arteries. Magnetic resonance venography (MRV) is a related blood vessel study that is more specific for veins in and around the brain. Radionuclide tests (such as PET scan) may also be performed to image the brain to determine the extent of damage.

An electrocardiogram (EKG) may be performed to identify any cardiac problems that may have led to the stroke, such as a prior heart attack. Patients who have had a heart attack in the past are at increased risk of blood clots forming in the heart, which could trigger a stroke. Patients are also at increased risk of developing a stroke if arrhythmias (heart rhythm disorders) such as atrial fibrillation are present. Finally, because an ischemic stroke and a heart attack may have the same underlying cause (e.g., atherosclerosis), a physician may use an EKG to look for additional signs of heart disease.

Blood tests, including a complete blood count (CBC) and a lipid profile (cholesterol test) may also be performed. These tests may help identify whether a patient has certain risk factors associated with stroke, such as high cholesterol.

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Some additional tests may be performed to assess overall brain function, as measured by electrical activity. These tests can reveal how much neurological damage was done as a result of the stroke. Among the most common of these tests are:

Electroencephalogram (EEG). During this painless test, small metal electrodes are attached to the scalp. The electrodes are connected by wires (leads) to an electroencephalograph machine that charts the electrical activity of the brain.

Evoked potential study. A test of the nervous system that can measure the brain's response to sight, hearing and touch stimuli.

Treatment options for stroke

Emergency medical attention should be obtained (e.g., by calling 9-1-1) for anyone experiencing signs or symptoms of a stroke. Aspirin should not be used by people who may have suffered a stroke because aspirin can worsen symptoms of a hemorrhagic stroke (stroke due to bleeding in or around the brain). Patients who have experienced a stroke will most likely be taken to a nearby hospital.

Upon arriving at a hospital, medical staff will attempt to stabilize the patient using information obtained from an emergency computed axial tomography (CAT) scan of the patient.

The focus of immediate care for patients who have suffered a stroke is to re-establish blood flow to the brain. However, when blood flow is restored (reperfusion) to the affected area of the brain, there is the risk that additional damage may occur. Returning blood carries white blood cells that may create a blockage in small blood vessels and may release toxins harmful to brain cells . Nevertheless, brain cells deprived of oxygen can die within minutes, causing long–term disability or death. Thus, re-establishing blood flow is a critical first step in emergency treatment of a person who has had a stroke.

Additional treatment methods that may be used for people who have had a stroke include:

Aid breathing. Maintaining breathing in patients who may be losing consciousness may be done through the use of breathing equipment and/or supplemental oxygen.

Reduce fever. If fever is present, it may be reduced with medications. Administer certain medications in cases of ischemic stroke (stroke due to restricted blood

flow to the brain). If a patient has had an ischemic stroke, medications that dissolve blood clots (thrombolytic medications) may be given intravenously. The most common thrombolytic medication is known as tissue plasminogen activator (tPA), which has been approved for use in treating strokes since 1996. It is most effective if administered within three hours of the onset of symptoms. Aspirin may also be beneficial for patients who have had an ischemic stroke (but not hemorrhagic stroke).

Prevent nutritional deficiency, Special attention may need to be provided to meeting a patient’s nutritional needs (intravenously or through the mouth) and to preventing pneumonia, a common complication after a stroke.

In cases where the stroke was caused by a partial blockage of a carotid artery (artery that carries blood from the heart to the brain) in the neck, a surgery called carotid endarterectomy may be performed to remove the accumulated plaque in the artery. In other cases, a cerebral angioplasty may be performed. This involves the use of a balloon-tipped catheter to stretch blood vessels in the brain and improve blood flow.

People who survive a stroke often need to undergo physical therapy to deal with impaired movement or speech that can occur as the result of a stroke. The sooner this treatment is begun, the more likely it is that patients will regain significant functioning. People who have had a stroke may also experience depression, which may be related to the temporary or permanent loss of body functioning. If depression occurs, patients are urged to seek the help of a qualified counselor for support and treatment.

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Prevention methods for stroke

Preventive measures do not fully protect an individual against having a stroke but may help. These measures may include:

Controlling high blood pressure (hypertension). Blood pressure abnormalities should be continually monitored and controlled because they are a chief contributor to strokes.

Quitting smoking. The risk of stroke begins to decrease a few years after a person quits smoking.

Getting treatment for heart rhythm abnormalities such as atrial fibrillation or atrial flutter. For example, anticoagulant medications may help prevent the risk of a blood clot forming and traveling to the brain, which can cause a stroke.

Getting treatment for sleep apnea.

Learning stress management techniques and seeking help for depression or drug abuse. Cocaine use, especially, has been linked to hemorrhagic strokes (strokes due to bleeding in or around the brain).

Reducing cholesterol levels, perhaps by taking cholesterol-reducing medications.

Increasing amount of daily exercise. The U.S. Surgeon General recommends that adults participate in moderate physical activity for at least 30 minutes on most days of the week.

Maintaining an ideal weight.

Limiting use of alcohol to about one glass of wine or beer per day.

Controlling diabetes.

Eating a heart-healthy diet. Findings from a number of studies illustrate how a heart-healthy diet can decrease stroke risk:

o Women who ate fish more than five times a week were found to have a significantly lower risk of stroke than women who ate fish less than once a month. Fish is a good source of omega-3 fatty acids, a substance helpful in reducing cholesterol levels.

o People in rural Japan with high levels of vitamin C in their blood from eating large amounts of fruits and vegetables were found to be significantly less likely to have a stroke than those with the low levels of vitamin C. It is important to note that there is no proof that taking vitamin C supplements will produce the same effect, because researchers do not know which substances in the fruits and vegetables produced the effect.

o Women who ate large quantities of whole-grain foods were found to have a decreased risk of ischemic stroke (stroke due to restricted blood flow to the brain), compared to women who ate little or no whole-grain foods.

In addition, some people may be advised by their physician to take aspirin or other antiplatelet agents to help prevent the formation of blood clots.

Surgery may be recommended for high-risk patients to help prevent the risk of stroke. This includes patients who have already had a stroke or transient ischemic attack, or people with a greater than 80 percent blockage in the carotid arteries (arteries that carry blood from the heart to the brain).

In some cases, a physician may recommend carotid artery stenting, a procedure in which tiny mesh tubes are placed in arteries to crush arterial plaque and improve blood flow through the

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arteries. It also helps prevent pieces of plaque from breaking off and traveling through the bloodstream, helping to prevent strokes. The Food and Drug Administration approved carotid artery stents in September 2004 for use in certain patients.

Alternatively, a surgical procedure called a carotid endarterectomy may help prevent strokes in certain patients. A carotid endarterectomy involves the removal of fatty build-up from the carotid arteries. While the patient is under general anesthesia, the plaque from the artery is removed, along with the entire inner lining of the artery.

Early detection and repair of a cerebral aneurysm may also prevent a stroke. If a cerebral aneurysm has not yet ruptured, but produces signs or symptoms that lead patients to seek medical attention, a stroke may be avoided. Surgery may be necessary to repair the aneurysm, a procedure sometimes called “clipping.” It involves snipping off the aneurysm before it can rupture. Another technique for repairing cerebral aneurysms is the detachable coil technique. In this minimally invasive procedure, a small coil is implanted into the bulge in the arterial wall. The coil provokes an immune system response from the body, which produces a blood clot inside the aneurysm that strengthens arterial walls and reduces the risk of a rupture and possible stroke.

Ongoing research regarding stroke

Surgery, medications, hospital care and rehabilitation efforts are all considered accepted methods of treating a patient who has suffered a stroke. Scientists are also continuously exploring new methods of treating and preventing strokes. Research is ongoing in many different areas, including:

Antibiotics. Studies have found that plaque that causes a hardening of the arteries (atherosclerosis) may also harbor bacteria that can increase the risk of arterial rupture. Researchers are investigating whether antibiotics can affect these bacteria, potentially reducing the risk of stroke.

Mechanical thrombolysis (use of physical means to break up blood clots). Certain devices that use catheter-delivered tools to break up or remove blood clots are being explored for use in helping to prevent strokes. Currently, medications are the only method available to break up a blood clot in the brain and can take up to an hour to be effective. Devices being tested include lasers, sound waves, suction, spinning blades and snares.

Neuroprotective agents. Certain substances are being studied that may protect brain cells from injury and help prevent brain damage as a result of some types of stroke. The substances being explored operate in different ways. For example, some may increase blood flow to the area of brain experiencing a stroke. Others may prevent damage that can be caused when blood returns to the affected area of the brain after a stroke. Still other substances may limit the damage caused by dying brain cells.

Stem cell transplants. Stem cells are “beginner” cells that have the ability to develop into many different types of cells. The cells start out similar but become highly specialized, depending on where in the brain they develop. Researchers are investigating a variety of methods in which stem cell transplants could be used as a treatment for brain damage caused by stroke and other conditions.

Hypothermia (bodily response to low temperatures). When exposed to low temperatures, the body responds in a variety of ways, including lowering the demand for oxygen to the brain. Researchers are studying whether lowering a patient’s body temperature can decrease the amount of brain damage that can occur during a stroke.

Cholesterol-lowering drugs. Recent studies indicate that cholesterol-lowering drugs called statins may decrease a patient’s stroke risk.

Electrical brain stimulation. Researchers are examining the potential benefits of short-term electrical stimulation, via electrodes attached to the head, during rehabilitation after a stroke. This may stimulate the cortex and enhance post-stroke learning.

More investigation is needed to determine the safety and effectiveness of these potential treatments and preventive measures.

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Questions for your doctor regarding stroke

Preparing questions in advance can help patients to have more meaningful discussions with healthcare professionals regarding their condition. Patients may wish to ask their doctor the following questions related to stroke:

1. How likely am I to have a stroke? Why?

2. What symptoms may indicate I am having a stroke?3. How will I know if I have a “silent stroke” (stroke without any obvious symptoms)?4. Are there any tests available to me that would indicate whether or not I have had a stroke?

How do I prepare for these tests?5. What type of testing will you need to perform after I have had a stroke? What information

will this tell you?6. What type of stroke did I have? What was the extent of brain damage ? Was there any

permanent damage?7. What treatment options are available to me?8. Do any of my current medications or medical conditions interfere with these treatments, or

affect my risk of stroke?9. Do you recommend that I undergo any type of physical therapy, occupational therapy or

speech therapy?10. How can I protect myself against future strokes?

Stroke Rehabilitation

Summary

Stroke rehabilitation is a method of treatment that helps stroke patients to relearn basic skills lost after a stroke. Each year, more than 700,000 people in the United States experience a stroke, and two-thirds of those people eventually require rehabilitation, according to the National Institutes of Health.

During a stroke, many patients experience damage to the brain that affects the ability to perform physical and cognitive functions. Rehabilitation helps patients with stroke-related brain damage to learn new ways of performing basic skills such as communicating, dressing, eating and walking. Rehabilitation also can increase a patient’s endurance, flexibility, balance, coordination and strength.

A stroke can have a wide array of effects on a person’s mental and physical abilities. These include:

Paralysis or problems controlling movement Sensory disturbances Problems using or understanding language (aphasia) Problems with thinking and memory Emotional problems (e.g., depression)

Following a stroke, several different types of medical professionals may help patients to regain as much of their normal abilities as possible. A patient’s primary physician and other specialist physicians such as neurologists have the leading role in planning a patient’s post-stroke care. Other medical professionals involved in rehabilitation include nurses, physical therapists , occupational therapists, speech pathologists and recreational therapists.

Typically, rehabilitation efforts begin within 24 to 48 hours following a stroke. In this initial period, patients are asked to change positions frequently while in their hospital bed and to perform basic range-of-motion exercises.

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Once patients are discharged from the hospital, they will either return home or enter some type of inpatient medical facility depending on the extent of brain damage from the stroke. Patients are likely to undergo stroke rehabilitation for an extended period of time, although the most significant improvements are typically noticed during the first six months of therapy.

Patients who successfully complete stroke rehabilitation are urged to make certain lifestyle changes that will reduce their risk of experiencing a second stroke. These include controlling certain diseases that can cause stroke, eating a healthy diet, engaging in regular exercise and not smoking.

About stroke rehabilitation

Stroke rehabilitation is a treatment method that helps patients who have experienced a stroke relearn basic skills lost after the stroke. Rehabilitation helps patients with stroke-related brain damage to learn new ways of performing basic skills such as dressing, eating and walking. Rehabilitation also can increase a patient’s endurance, flexibility, strength and ability to communicate.

Each year, more than 700,000 people in the United States experience a stroke. Two-thirds of these people eventually require rehabilitation, according to the National Institutes of Health (NIH). Stroke is the leading cause of disability in the United States, with more than 4 million Americans currently living with the effects of stroke.

Every stroke is unique and the effect on the patient depends on the location and extent of brain damage, as well as the person’s overall health status before the stroke occurred. People who have a hemorrhagic stroke (which involves bleeding around the brain) are more likely to sustain severe damage than people who have an ischemic stroke (where blood supply to the brain is blocked). According to the NIH:

10 percent of stroke patients recover completely 25 percent recover with minor impairments 40 percent experience moderate to severe impairments 15 percent die shortly after their stroke

Most people who experience a stroke will require some form of rehabilitation therapy. Rehabilitation cannot reverse the brain damage caused by stroke. Unlike some types of cells (e.g., skin cells ), brain cells do not regenerate after they have been damaged or killed.

However, the brain can be trained to adapt to cellular damage in ways that allow patients to learn to function by using undamaged nerve cells. Therapy can provide patients with skills that help enhance their quality of life. In some cases, patients may need to relearn old skills. For example, patients who have experienced certain types of stroke-related brain damage may need to relearn how to coordinate their leg movements so they will be able to walk.

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In other cases, patients may have to learn new ways of performing tasks that help them overcome damage that occurred during the stroke. For example, patients who have lost the ability to use their left arm may need to learn how to bathe and dress using only their right arm. Patients whose speech has been damaged will need to learn new ways of talking.

Experts believe that rehabilitation is most successful in patients who undertake repetitive practice of their new skills under the guidance of a rehabilitation expert. Other factors that influence the outcome of rehabilitation efforts include the extent of damage to the brain, rapidity of emergency medical treatment, promptness of rehabilitation efforts following the stroke and the skill of the patient’s rehabilitation team.

The willingness of family and friends to support the patient during rehabilitation is often a major factor in the long term success of rehabilitation efforts. Most patients make the greatest improvement during the first three to six months of rehabilitation. However, other patients may continue to progress over a long period of rehabilitation time.

Damage that may require stroke rehabilitation

A stroke can have a wide array of effects on a person’s mental and physical abilities. The type of damage that occurs depends on the part of the brain that has been damaged. There are five major types of stroke-related damage:

Paralysis or problems controlling movement. Paralysis is among the most common difficulties caused by stroke, and usually affects one side of the body (hemiplegia). In most cases, paralysis occurs on the side of the body that is opposite to the side of the brain that has been damaged. If the damage is confined to weakness rather than paralysis, it is known as hemiparesis. Some patients also may have trouble swallowing (dysphagia) or coordinating movements (ataxia) as a result of damage to the brain.

Problems using or understanding language (aphasia). About 25 percent of stroke survivors experience language impairment, according to the National Institutes of Health. This can affect the ability to speak, write, read and understand verbal communication.

Sensory disturbances. Some patients experience damage that limits their ability to feel pain, position, temperature or touch. Pain, numbness or other sensations may occur in compromised limbs (paresthesia).

Problems with thinking and memory. Strokes can damage portions of the brain used for awareness, learning and memory. This can result in a variety of symptoms ranging from memory loss to an inability to plan or complete complex tasks.

Emotional problems. Certain emotions are common in people who have had strokes. These include anger, anxiety, fear, frustration, grief and sadness. Clinical depression is the emotional disorder most often associated with stroke.

People who survive a stroke may have other symptoms related to brain damage. For example, problems with vision are common in people after a stroke. The eyes and brain function together to produce images and stroke can cause blurred vision , eye strain and other vision disturbances. A vision test is recommended after a stroke to assess any stroke-related damage. Additionally, incontinence of the bladder and bowels may occur after a stroke. Exercises for retraining the pelvic muscles may be advised, as well as establishing a regular voiding schedule.

“Learned disuse” is another common problem experienced by stroke survivors. This phenomenon develops when the patient repeatedly attempts to move a limb that has been paralyzed by stroke in the immediate post-recovery period. When this occurs, patients may stop using the limb completely, even though, over time, it may be capable of movement. Rehabilitation specialists use a method called constrained-induced movement therapy, which immobilizes the limb not affected by stroke and forces the patient to relearn to use the affected limb.

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People who help with stroke rehabilitation

Following a stroke, several different types of medical professionals may help patients to regain as much normal function as possible. A patient’s primary physician and other specialist physicians have the leading role in planning a patient’s post-stroke care. Physician specialists who may play an essential role in stroke rehabilitation include neurologists and physiatrists (specialists in physical medicine and rehabilitation).

Nurses also play a key role in managing a patient’s stroke rehabilitation. Nurses often are involved in helping patients carry out the basic activities of daily living, such as eating, bathing and toileting. In addition, they may provide guidance in planning a medication schedule and perform other personal care tasks.

Other specialists who may be involved in stroke rehabilitation include:

Physical therapist. Helps patients cope with motor and sensory disabilities. These experts may help patients to relearn how to use impaired or paralyzed limbs. They may also suggest exercises that the patient can perform to maintain strength and reduce fatigue.

Occupational therapist. Helps patients learn self-directed day-to-day activities. Occupational therapists focus on developing fine motor skills, such as those involved with personal grooming and preparing meals.

Speech-language pathologist. Helps patients relearn language techniques or to master new techniques that allow them to circumvent their disabilities. A speech-language pathologist may also be able to help patients relearn how to swallow, an activity that is often impaired following a stroke.

Recreational therapist. Helps patients learn thinking and movement skills that will help enhance the quality of leisure time. Recreational therapists may be able to help patients reduce stress and frustration using a variety of recreational activities, such as sports, games and community outings.

Visual therapist. Helps patients use various techniques to retrain, strengthen or sharpen visual skills that have been impaired due to damage in certain parts of the brain.

Vocational therapist. Helps educate stroke patients about their rights and protections as covered by the Americans with Disabilities Act (ADA). These therapists also help patients with disabilities identify physical and mental strengths and find positions of employment that match those strengths.

In addition, mental health professionals can help patients come to terms with emotional problems that they may be experiencing. Depression is a common symptom among people who have suffered a stroke. Other patients may experience involuntary emotional expression disorder, in which they have difficulty controlling emotional responses. Individual or group counseling may be a valuable component of rehabilitation for both the patient and the patient’s family.

Finally, social workers and case managers may be part of a patient’s care. These people help patients and their family make certain decisions, such as those related to finances or insurance. They may also help coordinate care for the patient. For example, a social worker or case manager may work with the patient’s family to develop plans to return home or enter a long-term care facility.

The patient’s local community may also have resources for stroke rehabilitation, such as home delivery of hot meals and volunteer companion visits.

How stroke rehabilitation unfolds

Typically, rehabilitation efforts begin within 24 to 48 hours following a stroke. This usually occurs in an acute-care hospital. Patients are asked to change positions frequently while in bed and to perform basic range-of-motion exercises. These may help stimulate and strengthen limbs damaged by the stroke. Over time, patients may be encouraged to sit up

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and to move from the bed to a chair. Once patients have begun to walk, they may progress to more complicated tasks, such as bathing, dressing and using a toilet.

Once patients are discharged from the hospital, they either return home or enter a type of inpatient medical facility, depending on the severity of impairment. In general, physicians try to encourage individuals to participate in the most rigorous rehabilitation program that they can handle. This is usually determined by taking into account the patient’s age, degree of disability and overall health.

Patients who are able to return home may attend rehabilitation sessions at an outpatient facility, which is often attached to a larger hospital complex. Patients usually attend these sessions a few times each week for several hours per session. Nursing facilities also may offer outpatient rehabilitation, although such services may be offered for fewer hours than at other outpatient centers.

Home-based rehabilitation is available for many patients, and is especially useful for those without access to transportation or who require treatment from just one type of rehabilitation therapist. Home-based rehabilitation may not be an option for patients who need access to specialized rehabilitation equipment.

Patients with severe impairments may not be able to return home immediately. Instead, they will enter inpatient rehabilitation units, where they may stay for two to three weeks. Therapy sessions may last for three hours and may be scheduled for up to five or six days each week. At the end of this time, patients may be able to return home or they may be admitted to a long-term care facility. About 10 percent of stroke survivors require care in a nursing home or other long-term care facility, according to the National Institutes of Health.

Most patients are involved in rehabilitation programs for several months following their stroke. However, the time required for rehabilitation differs depending on the severity of the patient’s brain damage and which functions are affected. 

Rehabilitation may take many forms, depending on the nature and extent of the patient’s impairments. For example, physical therapists and occupational therapists design repetitive exercise plans for patients, which are aimed to improve the patient’s basic ability to move and function. This many include using a treadmill to help a patient relearn to walk. Physical therapy may also involve helping a patient learn how to use a wheelchair or other assistive device. Physical therapists can assist patients in dealing with fatigue, which is common after stroke. The patient can be taught methods to move more efficiently, conserve energy, and gradually build physical stamina to combat fatigue.

For patients with aphasia or other problems with speech or language, speech therapy may be recommended. During this type of therapy, patients may be given exercises to improve the muscles necessary for speech and swallowing. Patients may also be shown ways to circumvent their speech problems by using alternate forms of communication. 

Therapists may also use a technique called transcutaneous electrical nerve stimulation (TENS) to encourage brain reorganization and regain lost functions. TENS is one of the most common types of electrical therapy and is usually used to treat pain. During the treatment, a small, battery-operated device sends low-voltage electrical current through the skin via electrodes (small, flat rubber adhesive discs). The electricity stimulates the nerves in the affected area and sends signals to the brain that may promote movement.

Lifestyle considerations for stroke rehabilitation

Stroke rehabilitation can help patients to regain some of the physical and mental skills lost as a result of injuries associated with the stroke. However, about 14 percent of stroke survivors will experience a second stroke in the year after the first stroke, according to the U.S. National Institutes of Health.

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For this reason, it is important that stroke patients take steps to help prevent future strokes. Factors known to increase the risk for a second stroke include:

Diabetes Heart disease High blood pressure (hypertension) High blood cholesterol levels History of transient ischemic attack (TIA) Obesity Older age Sedentary lifestyle Smoking

People with these risk factors are urged to take steps to eliminate one or more if possible. For example, people who are obese can eliminate several risk factors by losing weight through exercising and eating a healthy diet.

Questions for your doctor about rehabilitation

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions and treatments. Patients may wish to ask their doctor the following questions related to stroke rehabilitation:

1. What kind of stroke rehabilitation do you recommend? Why?

2. Which of my physical and cognitive impairments may be helped by rehabilitation?

3. Do I have any impairment that is unlikely to be helped by rehabilitation?4. When will my rehabilitation begin?5. Who will be involved in supervising my rehabilitation?6. Will I require inpatient or outpatient rehabilitation?7. How many hours per week will I be in rehabilitation?8. How long will my rehabilitation continue?9. What are some typical signs that indicate that rehabilitation efforts are

working?10. What steps can I take to prevent a second stroke?

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Many Doctors Don't Know Blood Pressure Guidelines

Sept. 19 (HealthDay News) -- Too many family doctors don't start treatment of middle-aged men with high blood pressure when they should, a new study indicates.

The men in the study happened to be black, but the same is probably true for men in general, said Dr. Joseph Ravenell, who was expected to report the findings Friday at the American Heart Association's Council for High Blood Pressure Research annual meeting, in Atlanta.

Traditionally, most of the emphasis has been on patient behavior, such as noncompliance with medication and access to care, said Ravenell, who did the study while at the University of Texas Southwestern Medical Center at Dallas; he is now an assistant professor of medicine at New York University. But there is increasing evidence that the problem of poor hypertension control is not just about patients.

Ravenell and his Texas colleagues interviewed 891 black men in Dallas County, most of them being treated by primary-care physicians. The researchers also interviewed 22 community doctors, asking whether they would start drug treatment for a 45-year-old black man with an office blood pressure of 145/92 and an out-of-office pressure of 154/95, both well above the recommended 120/80 level.

Only 36 percent of the doctors said they would start treatment, Ravenell reported. And none of the 22 said they were familiar with the national guidelines calling for treatment of blood pressure at such levels.

The results are somewhat surprising but are consistent with other results in the literature which suggest that the guidelines aren't adhered to by physicians nearly as well as the guideline creators would like, Ravenell said.

How different the results might have been if the men were not black is uncertain, he said. Evidence does not suggest that blacks suffer more from poor guideline adherence by physicians, but that is still an open question, Ravenell said. It would be an interesting study to see if the same scenario with white men produced the same results, he added.

There is a lesson in the study for doctors, he said. The particular lesson is that physicians need to take a very good look at their own practices to make sure they are appropriately applying the guidelines to all patients, but particularly to black men, who are at high risk of death from hypertension, Ravenell said.

One lesson for people who are seen by the doctors is that people need to be aware of the guidelines, said Dr. Daniel Jones, vice chancellor for health affairs at the University of Mississippi, and a past president of the American Heart Association .

Another lesson is that they should know their blood pressure numbers and should speak up if the readings indicate high blood pressure, he said. Patients can influence doctors' choices by initiating discussions, Jones said.

National health surveys show that Americans are becoming more aware of the dangers of high blood pressure, a major risk factor for heart attack and stroke, and that it can be controlled by drug therapy, Jones said.

SOURCES: Joseph Ravenell, M.D., assistant professor, medicine, New York University; Daniel Jones, M.D., vice chancellor, health affairs, University of Mississippi, Jackson; Sept. 19, 2008, American Heart Association's Council for High Blood Pressure Research, Atlanta

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