Stroke

Also called hypertension, this is by far the most potent risk factor for stroke. If your blood pressure is high, you and your doctor need to work out an individual strategy to bring it down to the normal range. Some ways that work: Maintain proper weight. Avoid drugs known to raise blood pressure. Cut down on salt. Eat fruits and vegetables to increase potassium in your diet. Exercise more. Your doctor may prescribe medicines that help lower blood pressure. Controlling blood pressure will also help you avoid heart disease, diabetes, and kidney failure.

Cigarette smoking has been linked to the buildup of fatty substances in the carotid artery, the main neck artery supplying blood to the brain. Blockage of this artery is the leading cause of stroke in Americans. Also, nicotine raises blood pressure; carbon monoxide reduces the amount of oxygen your blood can carry to the brain; and cigarette smoke makes your blood thicker and more likely to clot. Your doctor can recommend programs and medications that may help you quit smoking. By quitting, at any age, you also reduce your risk of lung disease, heart disease, and a number of cancers including lung cancer.

Common heart disorders such as coronary artery disease, valve defects, irregular heart beat, and enlargement of one of the heart’s chambers can result in blood clots that may break loose and block vessels in or leading to the brain. The most common blood vessel disease, caused by the buildup of fatty deposits in the arteries, is called atherosclerosis. Your doctor will treat your heart disease and may also prescribe medication, such as aspirin, to help prevent the formation of clots. Your doctor may recommend surgery to clean out a clogged neck artery if you match a particular risk profile. If you are over 50, NINDS scientists believe you and your doctor should make a decision about aspirin therapy. A doctor can evaluate your risk factors and help you decide if you will benefit from aspirin or other blood-thinning therapy.

If you experience a TIA, get help at once. Many communities encourage those with warning signs to dial 911 for emergency medical assistance. If you have had a stroke in the past, it’s important to reduce your risk of a second one. Your brain helps you recover from a stroke by drawing on body systems that now do double duty. That means a second one can be twice as bad.

You may think this disorder affects only the body’s ability to use sugar, or glucose. But it also causes destructive changes in the blood vessels throughout the body, including the brain. Also, if blood glucose levels are high at the time of a stroke, then brain damage is usually more severe and extensive than when blood glucose is well-controlled. Treating diabetes can delay the onset of complications that increase the risk of one.

This prevents the formation of blood clots that can become lodged in a cerebral artery and cause strokes. Antiplatelet drugs prevent clotting by decreasing the activity of platelets, blood cells that contribute to the clotting property of blood. These drugs reduce the risk of blood-clot formation, thus reducing the risk of ischemic stroke. In the context of stroke, physicians prescribe antiplatelet drugs mainly for prevention. The most widely known and used antiplatelet drug is aspirin. Other antiplatelet drugs include clopidogrel and ticlopidine.

Anticoagulants reduce stroke risk by reducing the clotting property of the blood. The most commonly used anticoagulants include warfarin (also known as Coumadin® ) and heparin.

These agents are used to treat an ongoing, acute ischemic stroke caused by an artery blockage. These drugs halt the stroke by dissolving the blood clot that is blocking blood flow to the brain. Recombinant tissue plasminogen activator (rt-PA) is a genetically engineered form of t-PA, a thombolytic substance made naturally by the body. It can be effective if given intravenously within 3 hours of stroke symptom onset, but it should be used only after a physician has confirmed that the patient has suffered an ischemic stroke. Thrombolytic agents can increase bleeding and therefore must be used only after careful patient screening.

These medications protect the brain from secondary injury caused by stroke Although only a few neuroprotectants are FDA-approved for use at this time, many are in clinical trials. There are several different classes of neuroprotectants that show promise for future therapy, including calcium antagonists, glutamate antagonists, opiate antagonists, antioxidants, apoptosis inhibitors, and many others. One of the calcium antagonists, nimodipine, also called a calcium channel blocker, has been shown to decrease the risk of the neurological damage that results from subarachnoid hemorrhage.

Calcium channel blockers, such as nimodipine, act by reducing the risk of cerebral vasospasm, a dangerous side effect of subarachnoid hemorrhage in which the blood vessels in the subarachnoid space constrict erratically, cutting off blood flow.

is a surgical procedure in which a doctor removes fatty deposits (plaque) from the inside of one of the carotid arteries, which are located in the neck and are the main suppliers of blood to the brain. As mentioned earlier, the disease atherosclerosis is characterized by the buildup of plaque on the inside of large arteries, and the blockage of an artery by this fatty material is called stenosis.

Currently, the NINDS is sponsoring the Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST), a large clinical trial designed to test the effectiveness of carotid endarterectomy versus a newer surgical procedure for carotid stenosis called stenting. The procedure involves inserting a long, thin catheter tube into an artery in the leg and threading the catheter through the vascular system into the narrow stenosis of the carotid artery in the neck. Once the catheter is in place in the carotid artery, the radiologist expands the stent with a balloon on the tip of the catheter. The CREST trial will test the effectiveness of the new surgical technique versus the established standard technique of carotid endarterectomy surgery.

is a procedure that restores blood flow to a blood-deprived area of brain tissue by rerouting a healthy artery in the scalp to the area of brain tissue affected by a blocked artery.

For most stroke patients, physical therapy (PT) is the cornerstone of the rehabilitation process. A physical therapist uses training, exercises, and physical manipulation of the stroke patient’s body with the intent of restoring movement, balance, and coordination. The aim of PT is to have the stroke patient relearn simple motor activities such as walking, sitting, standing, lying down, and the process of switching from one type of movement to another.

Another type of therapy involving relearning daily activities is occupational therapy (OT). OT also involves exercise and training to help the stroke patient relearn everyday activities such as eating, drinking and swallowing, dressing, bathing, cooking, reading and writing, and toileting. The goal of OT is to help the patient become independent or semi-independent.
Speech and language problems arise when brain damage occurs in the language centers of the brain. Due to the brain’s great ability to learn and change (called brain plasticity), other areas can adapt to take over some of the lost functions.

This type of therapy helps stroke patients relearn language and speaking skills, or learn other forms of communication. Speech therapy is appropriate for patients who have no deficits in cognition or thinking, but have problems understanding speech or written words, or problems forming speech. A speech therapist helps stroke patients help themselves by working to improve language skills, develop alternative ways of communicating, and develop coping skills to deal with the frustration of not being able to communicate fully. With time and patience, a stroke survivor should be able to regain some, and sometimes all, language and speaking abilities.

A common disability that results is paralysis on one side of the body, called hemiplegia. A related disability that is not as debilitating as paralysis is one-sided weakness or hemiparesis. The paralysis or weakness may affect only the face, an arm, or a leg or may affect one entire side of the body and face. A person who suffers a stroke in the left hemisphere of the brain will show right-sided paralysis or paresis. Conversely, a person with a stroke in the right hemisphere of the brain will show deficits on the left side of the body. A stroke patient may have problems with the simplest of daily activities, such as walking, dressing, eating, and using the bathroom.

Motor deficits can result from damage to the motor cortex in the frontal lobes of the brain or from damage to the lower parts of the brain, such as the cerebellum, which controls balance and coordination. Some stroke patients also have trouble eating and swallowing, called dysphagia.

Stroke may cause problems with thinking, awareness, attention, learning, judgment, and memory. If the cognitive problems are severe, patient may be said to have apraxia, agnosia, or “neglect.” In the context, neglect means that a stroke patient has no knowledge of one side of his or her body, or one side of the visual field, and is unaware of the deficit. A patient may be unaware of his or her surroundings, or may be unaware of the mental deficits that resulted from the stroke.

Stroke victims often have problems understanding or forming speech. A deficit in understanding speech is called aphasia. Trouble speaking or forming words is called dysarthria. Language problems usually result from damage to the left temporal and parietal lobes of the brain.

A stroke can lead to emotional problems. Patients may have difficulty controlling their emotions or may express inappropriate emotions in certain situations. One common disability that occurs with many patients is depression. Post-stroke depression may be more than a general sadness resulting from the incident. It is a clinical behavioral problem that can hamper recovery and rehabilitation and may even lead to suicide. Post-stroke depression is treated as any depression is treated, with antidepressant medications and therapy.

Stroke patients may experience pain, uncomfortable numbness, or strange sensations after a stroke. These sensations may be due to many factors including damage to the sensory regions of the brain, stiff joints, or a disabled limb. An uncommon type of pain resulting is called central stroke pain or central pain syndrome (CPS).

CPS results from damage to an area in the mid-brain called the thalamus. The pain is a mixture of sensations, including heat and cold, burning, tingling, numbness, and sharp stabbing and underlying aching pain. The pain is often worse in the extremities – the hands and feet – and is made worse by movement and temperature changes, especially cold temperatures. Unfortunately, since most pain medications provide little relief from these sensations, very few treatments or therapies exist to combat CPS.

Several studies have shown that menopause can increase a woman’s risk of stroke. Fortunately, some studies have suggested that hormone replacement therapy can reduce some of the effects of menopause and decrease stroke risk. Currently, the NINDS is sponsoring the Women’s Estrogen for Stroke Trial (WEST), a randomized, placebo-controlled, double-blind trial, to determine whether estrogen therapy can reduce the risk of death or recurrent stroke in postmenopausal women who have a history of a recent TIA or non-disabling stroke. The mechanism by which estrogen can prove beneficial to postmenopausal women could include its role in cholesterol control. Studies have shown that estrogen acts to increase levels of HDL while decreasing LDL levels.

Subarachnoid hemorrhage, in particular, causes one to five maternal deaths per 10,000 pregnancies.
A study sponsored by the NINDS showed that the risk of stroke during pregnancy is greatest in the post-partum period – the 6 weeks following childbirth. The risk of ischemic stroke after pregnancy is about nine times higher and the risk of hemorrhagic stroke is more than 28 times higher for post-partum women than for women who are not pregnant or post-partum. The cause is unknown.

In the same way that the hormonal changes during pregnancy and childbirth are associated with increased risk of stroke, hormonal changes at the end of the childbearing years can increase the risk of stroke.

Other studies have demonstrated that pregnancy and childbirth can put a woman at an increased risk for stroke. Pregnancy increases the risk of stroke as much as three to 13 times. Of course, the risk of stroke in young women of childbearing years is very small to begin with, so a moderate increase in risk during pregnancy is still a relatively small risk. Pregnancy and childbirth cause strokes in approximately eight in 100,000 women. Unfortunately, 25 percent of strokes during pregnancy end in death, and hemorrhagic strokes, although rare, are still the leading cause of maternal death in the United States.