What Is Vascular Dementia?

Vascular dementia (VaD) is the second most common form of dementia after Alzheimer's disease (AD). It's caused by damage to brain tissue, which occurs because of decreased blood flow. Blood flow to brain tissue may be completely blocked by a clot in a blood vessel, or blood flow may be decreased but not completely blocked by a partial blockage in blood vessels in the brain.

VaD may develop gradually, or it may become apparent after a stroke or after undergoing major surgery, such as heart bypass surgery or abdominal surgery.

Facts about vascular dementia

Dementia and other related diseases and conditions are difficult to distinguish because they share similar signs and symptoms. Although vascular dementia is caused by problems with blood flow to the brain, this blood flow problem can happen in different ways. So, different types of VaD are based on how each type occurs:

• Mixed dementia. In some cases, symptoms of both VaD and AD exist. When mixed dementia occurs, however, it is generally considered to be a form of dementia with some characteristics of AD, rather than a case of AD with characteristics of vascular dementia.
• Multi-infarct dementia. This occurs after several small, often "silent," blockages repeatedly affect blood flow to a certain area of the brain. The changes that occur after each blockage may not be apparent, but over time, the combined effect begins to cause symptoms of impairment. Multi-infarct dementia is also called vascular cognitive impairment.

Men, especially those younger than 75, are affected by vascular dementia more often than women.

Researchers think that VaD will become more common in the next few decades because:

• VaD is generally caused by conditions that occur most often in older people, such as atherosclerosis (hardening of the arteries), heart disease, and stroke.
• The number of people older than 65 years is increasing.
• People are living longer with chronic diseases such as heart disease and diabetes.