A stroke occurs either when the blood supply to part of the brain is blocked or when a blood vessel in the brain bursts, causing damage to a part of the brain. A stroke is also sometimes called a brain attack. Strokes can—and do—occur at ANY age. Nearly one quarter of strokes occur in people under the age of 65.

Causes

Caused by a number of trigers, what sets them in motion is unknown at this point.

Risk Factors

Some conditions as well as some lifestyle factors can put people at a higher risk for stroke. The most important risk factors for stroke are high blood pressure, heart disease, diabetes, and cigarette smoking. Persons who have already had a stroke need to control the risk factors in order to lower their risk of having another stroke. All persons can take steps to lower their risk for stroke.

High Blood Pressure
High blood pressure, or hypertension, is a major risk factor for stroke. It is a condition where the pressure of the blood in the arteries is too high. There are often no symptoms to signal high blood pressure. About 60 million people in the United States have high blood pressure. Lowering blood pressure can lower the risk of stroke. Medicines to lower blood pressure can decrease the risk of stroke among those with high blood pressure.

Heart Disease
Common heart disorders such as coronary artery disease can also increase a person's risk for stroke. Coronary artery disease (CAD) occurs when the arteries that supply blood to the heart muscle become hardened and narrowed due to the buildup of plaque. Plaque (a mixture of fatty substances, including cholesterol and other lipids) and blood clots can build up inside the artery walls, causing thickening, hardening, and loss of elasticity. They can result in decreased or blocked blood flow and lead to a heart attack. Also, heart problems such as valve defects, irregular heart beat, and enlargement of one of the heart's chambers can result in blood clots that may break loose and cause a stroke. Persons with heart disease may be given medicines such as aspirin to help prevent clots from forming.

Atrial Fibrillation
A heart condition known as atrial fibrillation is a major concern. Atrial fibrillation is irregular beating of the upper chambers, or atria, of the heart. When the atria quivers instead of beating in a regular pattern, blood is not fully pumped out of them and may pool and clot. The clots can then leave the heart and travel to the brain, causing a stroke. Atrial fibrillation affects as many as 2.2 million Americans. About 15 percent of stroke patients have had atrial fibrillation before they experience a stroke.

Diabetes
Diabetes is another disease that increases a person's risk for stroke. With diabetes, the body does not make enough insulin, cannot use its own insulin as well as it should, or both. This causes sugars to be unavailable to the body tissues and to build up in the blood. People with diabetes have 2 to 4 times the risk of stroke compared to people without diabetes. Further, having diabetes can worsen the outcome of stroke.

Tobacco Use
Smoking almost doubles a person's risk for ischemic stroke, independently of other risk factors. Cigarette smoking increases the risk of stroke by promoting atherosclerosis and increasing the levels of blood clotting factors, such as fibrinogen. Also, nicotine raises blood pressure, and carbon monoxide reduces the amount of oxygen that blood can carry to the brain.

Blood Cholesterol Levels
Some strokes can be caused by a narrowing of the arteries through the buildup of plaque, a mixture of fatty substances, including cholesterol and other lipids. This is called atherosclerosis. Plaque and blood clots build up inside the artery walls, causing thickening, hardening, and loss of elasticity. These can lead to decreased blood flow and to stroke if they occur in the arteries to the brain.

Cholesterol is a waxy substance produced by the liver. It is needed by the body, and the liver makes enough cholesterol for the body's needs. Excess cholesterol—usually from eating foods that contain high levels of cholesterol and saturated fats—contributes to atherosclerosis.

There are two major kinds of cholesterol, one that is good, and one that is bad when there is too much of it. A higher level of high–density lipoprotein cholesterol, or HDL, is considered good. However, higher levels of low–density lipoprotein, or LDL, can lead to atherosclerosis and stroke.  A lipoprotein profile can be done to measure several different kinds of cholesterol as well as triglycerides (another kind of fat found in the blood).

Alcohol
Generally, excessive alcohol use can lead to an increase in blood pressure, which increases the risk for stroke.

Genetic
Stroke can run in families. Genes play a role in stroke risk factors such as high blood pressure, heart disease, diabetes, and vascular conditions. It is also possible that an increased risk for stroke within a family is due to factors such as a common sedentary lifestyle or poor eating habits, rather than hereditary factors.

Symptoms

• Sudden numbness or weakness of the face, arms, or legs

• Sudden confusion or trouble speaking or understanding others

• Sudden trouble seeing in one or both eyes

• Sudden trouble walking, dizziness, or loss of balance or coordination

• Sudden severe headache with no known cause

All of the major symptoms of stroke appear suddenly, and often there is more than one symptom at the same time.

Diagnosis

See physician for proper diagnosis.

Treatment

Medical treatments can help to control the risk factors that put people at higher risk for stroke. These include treating high blood pressure, heart disease, and diabetes. Lifestyle changes such as quitting smoking can also lower the risk of stroke.

Acute stroke therapies try to stop a stroke while it is happening. These treatments try to dissolve the blood clot causing an ischemic stroke or to stop the bleeding of a hemorrhagic stroke. These therapies are most effective when given very soon after the onset of a stroke.

Post–stroke treatment and rehabilitation are used to lower the risk of another stroke and to help patients overcome disabilities that result from stroke. People who have had a stroke can do things to lower their risk of having another stroke. These include controlling their underlying risk factors.

Rehabilitation helps stroke victims relearn skills that may be lost when the brain is damaged. Rehabilitation may include the following:

• Physical therapy to help restore movement, balance, and coordination.
  

• Occupational therapy to help the patient relearn everyday activities such as eating, drinking, dressing, bathing, cooking, reading and writing. 

• Speech therapy to help stroke patients relearn language and speaking skills, including swallowing, or learn other forms of communication. 

• Psychological or psychiatric help after a stroke. Psychological problems, such as depression, anxiety, frustration, and anger, can be common after a stroke.

Prevention

All people can take steps to lower their risk for stroke, whether they have had a stroke or not. Things you can do to lower the risk of stroke include steps to prevent and control high blood pressure, heart disease, and other chronic conditions.

Prevent and control high blood pressure: High blood pressure is easily checked. It can be controlled with lifestyle changes and with medicines when needed. You can work with your doctor to treat high blood pressure and bring it down. Lifestyle actions such as healthy diet, regular physical activity, not smoking, and healthy weight will also help you to keep normal blood pressure levels. All adults should have their blood pressure checked on a regular basis.

Prevent and control diabetes: People with diabetes have a higher risk of stroke, but they can also work to reduce their risk. Further, recent studies suggest that all people can take steps to reduce their risk for diabetes. These include weight loss and regular physical activity.

No tobacco: Smoking can affect a number of things that relate to risk of high blood pressure, heart disease, and stroke. Not smoking is one of the best things a person can do to lower their risk of stroke. Quitting smoking will also help to lower a person's risk of stroke. The risk of stroke decreases a few years after quitting smoking. Your doctor can suggest programs to help you quit smoking.

Treat atrial fibrillation: Atrial fibrillation is an irregular beating of the heart. It can cause clots that can lead to stroke. A doctor can prescribe medicines to help reduce the chance of clots.

Prevent and control high blood cholesterol: High blood cholesterol is a major risk factor for heart disease, which can increase the risk for stroke. Preventing and treating high blood cholesterol includes eating a diet low in saturated fat and cholesterol and higher in fiber, keeping a healthy weight, and getting regular exercise. A lipoprotein profile can be done to measure several kinds of cholesterol as well as triglycerides (another kind of fat found in the blood). All adults should have their cholesterol levels checked once every five years, and more often if it is found to be high.

Moderate alcohol use: Excessive alcohol use can increase the risk of high blood pressure. People who drink should do so in moderation.

Maintain a healthy weight: Healthy weight status in adults is usually assessed by using weight and height to compute a number called the "body mass index" (BMI). BMI is used because it relates to the amount of body fat for most people. An adult who has a BMI of 30 or higher is considered obese. Overweight is a BMI between 25 and 29.9. Normal weight is a BMI of 18 to 24.9. Proper diet and regular physical activity can help to maintain a healthy weight.

Regular Physical Activity: The Surgeon General recommends that adults should engage in moderate level physical activities for at least 30 minutes on most days of the week.

Diet and nutrition: Along with healthy weight and regular physical activity, an overall healthy diet can help to lower blood pressure and cholesterol levels. This includes eating lots of fresh fruits and vegetables, lowering or cutting out salt or sodium, and eating less saturated fat and cholesterol to lower the risk of high blood pressure and heart disease which can lead to stroke.

Genetic Risk Factors
Stroke can run in families. Genes play a role in stroke risk factors such as high blood pressure, heart disease, diabetes, and vascular conditions. It is also possible that an increased risk for stroke within a family is due to factors such as a common sedentary lifestyle or poor eating habits, rather than hereditary factors.

References

CDC