"Multi-infarct Dementia [also commonly referred to as 'Vascular Dementia'] is caused by a series of small strokes. Multi-infarct Dementia (MID) is the second most common cause of dementia after Alzheimer disease in people over age 65. MID usually affects people between ages 55 and 75. More men than women have MID.
A stroke is an interruption in or blockage of the blood supply to any part of the brain. A stroke is also called an infarct. Multi-infarct means that more than one area in the brain has been injured due to a lack of blood. If blood flow is stopped for longer than a few seconds, the brain cannot get oxygen. Brain cells can die, causing permanent damage.
When these strokes affect a small area, there may be no symptoms of a stroke. These are called silent strokes. Over time, as more areas of the brain are damaged, the symptoms of MID appear. Not all strokes are silent. Larger strokes that affect strength, sensation, or other brain and nervous system (neurologic) function can also lead to MID. Risk factors for MID include: diabetes, hardening of the arteries (atherosclerosis), high blood pressure (hypertension), smoking, and stroke."
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