Stroke (also called a "cerebrovascular accident," or CVA) is a disease of the blood vessels in and around the brain. It occurs when part of the brain does not receive enough blood to function normally (called "ischemia") and the cells die (infarction), or when a blood vessel ruptures (hemorrhagic stroke). Ischemia is more common than hemorrhage and has a number of causes: a vessel (artery) supplying blood to the brain can become blocked by a fatty deposit (plaque), which can form clots and send pieces into vessels further in the brain, or these arteries become thickened or hardened, narrowing the space where the blood flows (atherosclerosis). In addition, clots can arise in the heart (called a "thrombus") and travel to the brain (called an "embolus"). Permanent damage to brain cells can result.
Have you had a stroke? How could you tell?
A stroke is a sudden stop of blood supply to part of the brain. Some people have strokes without ever knowing it. These so-called silent strokes either have no easy-to-recognize symptoms, or you don’t remember them. But they do cause permanent damage in your brain.
If you've had more than one silent stroke, you may have thinking and memory problems. They can also lead to more severe strokes.
Common symptoms of stroke are sudden paralysis or loss of sensation in part of the body (especially on one side), slurred speech, partial loss of vision or double vision, or loss of balance. Loss of bladder and bowel control can also occur.
Other symptoms include decline in "cognitive" mental functions such as memory, speech and language, thinking, organization, reasoning, or judgment.
Changes in behavior and personality may occur.
If these symptoms are progressive and severe enough to interfere with everyday activities, they are called dementia or "major neurocognitive disorder."
Cognitive decline related to stroke is usually called vascular dementia or vascular cognitive impairment to distinguish it from other types of dementia. In the United States, it is the second most common form of dementia after Alzheimer's disease. Vascular dementia may be preventable, but only if the underlying vascular disease (such as hypertension) is recognized and treated early.
People who have had a stroke have a far greater risk of developing dementia than people who have not had a stroke. About 1 in 4 people who have had a stroke develop signs of dementia within 1 year.
Vascular dementia is most common in older people, who are more likely than younger people to have vascular diseases. It is more common in men than in women.