Although strokes most commonly affect those over the age of 65, about one-quarter of all stroke victims are under this age. A stroke affects the arteries that lead to and within the brain and is the 5th leading cause of death and disability in the United States. When a blood vessel carrying oxygen and nutrients to the brain is blocked by a blood clot or ruptures, the brain is unable to get the oxygen and blood it needs, resulting in the death of brain cells. An ischemic stroke is caused by a clot obstructing the flow of blood to the brain. A ruptured blood vessel causes a hemorrhagic stroke, and a mini-stroke or transient ischemic attack is the result of a temporary blood clot.