Also known as a cerebrovascular accident (CVA), a stroke is a life-threatening event in which part of the brain is deprived of adequate oxygen. A stroke can cause oxygen-starved brain cells to die. The condition must be treated immediately. According to the American Heart Association, stroke is the third leading cause of death in the United States, behind heart disease and cancer.

A stroke occurs when a blood vessel in the brain bursts or becomes clogged by a blood clot or other mass. This prevents oxygen and nutrients from getting to nerve cells in the affected area of the brain. These nerve cells can die within minutes, and the area of the body that they control may cease to function. This damage can be permanent, especially if the patient is not immediately treated.

There are two main types of strokes: Ischemic strokes and hemorrhagic strokes. An ischemic stroke occurs when the brain is deprived of oxygen. This is usually due to a blood clot in an artery leading to the brain. A hemorrhagic stroke is caused by excessive bleeding in or around the brain. It may be the result of factors such as high blood pressure, cerebral aneurysm or a head injury. In general, older adults are more likely to experience ischemic strokes, and young people are more likely to experience hemorrhagic strokes.  

In some cases, people experience the symptoms of a stroke for a brief period of time. These are called a transient ischemic attack (TIA) – also sometimes referred to as “mini-strokes” – because symptoms are less severe than an acute ischemic stroke, and go away fairly quickly (within minutes, in most cases). However, TIAs may indicate a serious medical complication that may cause another, more serious stroke at some point in the future.

In recent years, rapid treatment of stroke has advanced as physicians have become better at identifying what kind of stroke is occurring and moving quickly to treat it. This has resulted in a higher survival rate, but also a higher rate of hospitalization as more people survive their strokes.

The focus of stroke therapy remains rapid treatment to re-establish blood flow to the brain – but even this carries some risk. When blood flow is restored (a process known as reperfusion) to the affected area of the brain, further damage can occur. Returning blood carries white blood cells that can block smaller blood vessels and release toxins harmful to brain cells. Nevertheless, brain cells deprived of oxygen can die within minutes, causing long–term disability. If the flow of blood is restricted for too long, death could result. Therefore, the benefits of restoring blood flow to the brain are considered by physicians to outweigh the risks.

A stroke may occur in any person, regardless of age. However, strokes are more common in adults than children. When a person under the age of 18 suffers a stroke, it is known as a pediatric stroke. Because they are rare, pediatric strokes are often not recognized and treatment may delayed. This increases the risk of brain damage. Children tend to have different risk factors for stroke than adults, such as congenital heart disease, sickle cell anemia, and other conditions and traumas. It is important that families with children who are at risk of pediatric stroke learn to recognize the signs of stroke.

Although strokes occur with roughly equal frequency in both men and women, women are more likely to die from stroke. This may be due to the fact that women are less likely than men to receive rapid medical assessment and treatment for stroke.

Female stroke victims account for more than 60 percent of the annual deaths due to stroke, according to the American Heart Association. In addition, 25 percent of women who have suffered a stroke will die within a year, and about 50 percent of female stroke survivors will die within eight years. That means that stroke claims more women’s lives than breast cancer. For every American woman who dies of breast cancer, two more die of stroke.

African-Americans have a higher risk of stroke than most other ethnic groups. The reasons for this are poorly understood. However, it is thought to be related to poverty, lack of access to adequate health-care and genetic factors.