A stroke occurs when the blood supply carrying oxygen and nutrients to part of the brain is suddenly disrupted. Deprived of oxygen, cells in the affected are of the brain cannot function and begin to die within minutes.There are two types of stroke: ischemic, in which there is blockage of a blood vessel supplying the brain, and hemorrhagic, in which there is bleeding into or around the brain. Just as a person who experiences a loss of blood flow to the heart is said to suffer a “heart attack,” the person whose blood flow to the brain is interrupted or who suffers bleeding in the brain is having a “brain attack.”
What risk factors for stroke can be controlled or treated?
Some risk factors for stroke are beyond a person’s control. Things like a person’s age, gender, ethnicity/race or family history can influence the degree of risk for stroke. Yet, there are many lifestyle changes that can help to reduce your risk. Appropriate medical management of certain diseases and conditions also can cut your risk. Here are some factors that you control.
High blood pressure or hypertension is a silent disease. Many times, a person will have no signs or symptoms. This is why it is important to have regular medical checkups. If you find out you have high blood pressure – it should be less than 120/80 – it needs to be controlled. There are lifestyle changes you can make to lower your blood pressure. Eat a healthy diet low in salt, fat and cholesterol. If you are overweight, lose some pounds. If you have a sedentary lifestyle, develop an exercise plan. If your doctor prescribes medication for your blood pressure, be sure to take it as ordered. Do not skip any medication, even if you start feeling better and your blood pressure drops to within normal limits. If you stop taking your medication, your blood pressure will go up. People with uncontrolled hypertension are nearly seven times more likely to have a stroke than those who keep their blood pressure down.
If you have a disease of the heart, you are more prone to have a stroke. In fact, after high blood pressure, the second most important risk factor for stroke is heart disease. These include malformations of the heart valves or of the heart muscle. Another disease of the heart that increases a person’s risk of stroke is atrial fibrillation, or the irregular beating of the heart’s left upper chamber. This creates an uneven flow of blood and the occasional formation of clots that can leave the heart and travel to the brain where they cause a stroke. Atrial fibrillation affects more than 2 million people in the United States, most of them older, and increases their risk of stroke by 4 percent to 6 percent. In people 80 years of age and older, atrial fibrillation is directly responsible for one of every four strokes.
Controlling your diet and blood pressure, and increasing the amount of time you exercise will help to prevent the clogging of your arteries with plaque, a leading factor in heart attacks and brain attacks. You should also pay attention to your cholesterol levels. If your physician has prescribed medication to control a disease of the heart, be sure to take it as ordered.
If you have diabetes, your risk of stroke is two to four times higher than those who do not have the disease. Diabetes affects the body’s ability to produce and/or use insulin, a hormone that allows cells to absorb glucose, the body’s main source of fuel. If the body produces too little (or no) insulin, glucose builds up in the blood and can reach dangerous levels.
Diabetes can seriously harm blood vessels throughout the body, including those in the brain, which increases the risks of stroke. High blood glucose levels cause hardening of the arteries (atherosclerosis), thicken capillary walls and make blood stickier — all significant risk factors for ischemic stroke. The disease also can cause small vessels to leak, reducing blood flow to the body tissue.
If blood sugar (glucose) levels are high at the time of a stroke, brain damage may be more severe and extensive. This occurs because, when the brain is deprived of oxygen, the body breaks down glucose differently. The byproducts of this process, which can be found in and around the area of dead tissue, are toxic to the brain tissue. If blood circulation is restored to the area, these products will continue to break down, further increasing the size of the dead/damaged tissue area.
Treating diabetes can delay or prevent the onset of complications that increase the risk of stroke. Healthy eating, physical activity, and insulin via injection or an insulin pump are the basic therapies for type 1diabetes. Those with type 2 diabetes should adopt a healthy diet, increase their level of physical activity and monitor their blood glucose levels. In addition, many people with type 2 diabetes require oral medication, insulin injection, or both to control their blood glucose levels. It also is important that you lower your cholesterol level, control your blood pressure and stop smoking. Some research indicates that low doses of aspirin may prevent heart attacks and strokes. Check with your physician about whether this is something you should do. If you have questions about your diabetes or how to best manage the disease, be sure to discuss them with your physician.
The carotid arteries are the big blood vessels on both sides of your neck that supply blood to your brain. If you have carotid artery disease, this means plaque has collected on the inside of these blood vessels. Depending on the amount of plaque present, blood flow through these vessels may become progressively restricted. Plaque also may cause a blood clot to form in these arteries. In some cases, the arteries may become so clogged with plaque that there is no blood flow, which can cause a stroke. Your physician can order tests to determine if you have carotid artery disease, If so, there are various medical treatments to clean the arteries of the plaque.
If you smoke cigarettes, stop. (You should not use any other forms of tobacco.) Besides increasing your risk of stroke, smoking contributes to many medical problems, including cardiovascular disease, lung disease and cancer. The nicotine in cigarettes raises your blood pressure and, with it, your chances of developing hypertension. Cigarette smoke contains more than 4,000 chemicals – some of them carcinogenic – and can thicken the blood, making it more likely to clot. Even second-hand smoke, because it contains the same chemicals, has been linked to greater risk of stroke. Cigarette smoking also damages the lining of blood vessels and reduces the amount of oxygen the blood is able to carry.
A study published in the May 2003 issue of the American Heart Association’s journal Stroke showed that the risk of stroke increases depending on how many cigarettes a day you smoke. The study also found that former smokers and those who had never smoked had the same risk for all kinds of stroke, suggesting that quitting smoking can reduce the risk of stroke. So, if you smoke, check with your physician, a nearby hospital or your local health department for more information about smoking cessation classes or clinics. The Illinois Department of Public Health operates a Quitline; call 1-800-Quit Yes.
A transient ischemic attack (TIA) is a mini-stroke. It warns you that something is wrong. A person suffering a TIA may develop several symptoms or warning signs of a stroke but they go away in a short time (they usually pass within an hour). It is still important to go to a hospital immediately. Do not wait; call 911. A physician is the only person who can determine if you are having a TIA or a stroke. The diagnosis usually requires a CT scan or MRI to rule out a brain attack. More than one-third of those who have a TIA will have a stroke in the future. Working with your physician, you can determine any underlying factors that may have contributed to the TIA. Medication and lifestyle changes may help to prevent a stroke in the future.
Not being physically active and obesity can increase your risk of high blood pressure, high blood cholesterol, diabetes, stroke and heart disease. Regular exercise and a proper diet will help you to stay healthy. For example, regular exercise has been shown to increase your HDL (good cholesterol) levels and to decrease your triglycerides levels. So, don’t be a couch potato. You should try to do some form of exercise for 30 minutes a day at least five days a week. Check with your doctor; he/she will help you to put together an exercise plan that will help you to safely increase your activity level. Enroll a family member or friend in your exercise program; people tend to exercise more routinely when a friend or family member also participates.
A proper diet can help to fend off obesity. When you are overweight, your heart has to work harder to pump blood through your body. This puts excess stress on your circulatory system, which can damage blood vessels. Ask your doctor to determine your perfect weight for your height. One method your physician may use to determine your proper weight is to calculate your body mass index (BMI). The BMI formula assesses body weight relative to height. BMI values above 25.0 are considered overweight. Values greater than 30.0 are defined as obese. To calculate your BMI, take your weight in pounds and divide it by your height in inches squared; multiply that number by 703. Regardless of what method your physician may use to determine if you are overweight, he/she can recommend a diet plan that will help you to achieve a healthy weight.
If you do drink, do so in moderation. Excessive alcohol intake can raise your blood pressure and lead to stroke and heart disease. If you are a man, limit yourself to two drinks a day; if you are a woman, you should have only one drink a day.Cholesterol is a waxy, fat-like substance found in all cells of the body.A certain amount is needed by the body to stay healthy. However, a diet high in saturated fat and cholesterol can result in an overload in the blood stream and that can be dangerous. There are three different types of cholesterol in the body: good cholesterol (HDL), bad cholesterol (LDL) and triglycerides. To prevent brain and heart disease, it is important to increase the good cholesterol and to decrease the bad cholesterol and triglycerides. Some medical experts contend that HDL removes excess cholesterol from plaques and thus slows their growth. High levels of this "good" cholesterol seem to protect against heart attack. Low levels (less than 40 mg/dL in men; less than 50 mg/dL in women), on the other hand, can indicate a greater risk of heart disease and stroke. Elevated levels of LDL (160 mg/dL and above) and triglycerides (above 150 mg/dL) can lead to a condition known as atherosclerosis, or hardening of the arteries, which is characterized by the development of plaque, thick hard deposits that can clog arteries.
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