Stroke: Risk Factors and Prevention
A stroke occurs when a blood vessel breaks or when a blood clot blocks a blood vessel or artery. This interrupts blood flow and destroys brain cells in the immediate area; this area of dead brain cells is known as an infarct. After these cells die, chemicals are released, affecting brain cells in the surrounding area of brain tissue where blood supply is compromised. Symptoms of a stroke include numbness or weakness, usually on one side of the body in the face, arm, or leg; confusion, trouble speaking, or understanding; difficulty seeing in one or both eyes; trouble walking, dizziness, loss of balance or coordination; and severe headache with no known cause. If you experience any of these symptoms, seek medical attention immediately—more damage will occur the longer you wait to be treated, decreasing your chances of a full recovery.
A stroke causes skills such as intellect, sensation, perception, and movement to become impaired. The side effects that occur depend on what part of the brain was affected and on the extent of the brain damage. A stroke in the right hemisphere of the brain, for instance, often paralyzes the left side of the body, and causes impaired spatial and perceptual abilities, judgment difficulties, left-sided neglect (ie, when patients ignore objects or people on their left side), and problems with short-term memory.
Risk factors. Uncontrollable risk factors for stroke include being over age 55 years, male, and/or African American, and having diabetes and/or a family history of stroke. High blood pressure puts stress on the blood vessel walls and causes blood clots or hemorrhage; it is the most critical controllable risk factor. Atrial fibrillation causes blood to collect in the heart, which produces clots that can be carried to the brain. High cholesterol levels lead to plaque buildup on the inside of the arteries, which clogs arteries and causes heart attack or stroke. Sleep apnea increases blood pressure and may cause low levels of oxygen in the blood while carbon dioxide levels rise, which may lead to blood clots or strokes. Those who have had a stroke or transient ischemic attack are at risk for having another. In addition, smoking damages blood vessel walls, speeds up artery clogging, increases blood pressure, and makes the heart work harder. Excess weight places strain on your circulatory system, and leads to other stroke risk factors such as high cholesterol, high blood pressure, and diabetes.
Prevention. If you are a diabetic, make sure your diabetes is controlled by following your doctor’s recommendations. Your blood pressure should be measured at least annually. If it is high, your doctor will create a plan to lower your levels (eg, changes in your diet such as decreasing your salt and fat intake, exercise, and/or medication). Cholesterol can usually be controlled with diet and exercise, although some persons may require medication. Determine whether you suffer from sleep apnea or atrial fibrillation. The latter can be diagnosed by measuring your pulse, and confirmed by an electrocardiogram. Your doctor may prescribe a blood thinner such as warfarin or aspirin to control this condition. If you stop smoking and engage in regular excercise, your risk for stroke will subsequently begin to decrease. Finally, your doctor may prescribe anti-coagulants or antiplatelet drugs, which reduce your risk of stroke by preventing clots from forming.