Vascular dementia is loss of mental function due to destruction of brain tissue because its blood supply is reduced or blocked. The cause is usually strokes, either a few large ones or many small ones.
Vascular dementia is the second most common cause of dementia among older people.
A series of strokes may result in vascular dementia. These strokes are more common among men and usually begin after age 70. Risk factors for vascular dementia include the following:
High blood pressure, diabetes, and atherosclerosis damage blood vessels in the brain. Atrial fibrillation increases the risk of strokes due to blood clots from the heart. Unlike other types of dementia, vascular dementia can sometimes be prevented by correcting or eliminating the risk factors for strokes.
Strokes can destroy brain tissue by blocking the blood supply to parts of the brain. An area of brain tissue that is destroyed is called an infarct. Dementia may result from a few large strokes or, more commonly, many small ones. Some of these strokes seem minor or may not even be noticed. They cause little or no muscle weakness and no paralysis. However, people may continue to have small strokes, and after enough brain tissue is destroyed, dementia can develop. Thus, vascular dementia may develop before strokes cause severe symptoms or sometimes even any noticeable symptoms.
Vascular dementia includes the following, which may overlap somewhat:
Vascular dementia often occurs with Alzheimer disease (as mixed dementia).
Unlike dementia caused by Alzheimer disease, vascular dementia may progress in steps. Symptoms may worsen suddenly, then plateau or lessen somewhat. They then become worse months or years later when another stroke occurs. Dementia that results from many small strokes usually progresses more gradually than that due to a few large strokes. The small strokes may be so subtle that dementia may seem to develop gradually and continuously instead of in steps.
Symptoms (memory loss, difficulty planning and initiating actions or tasks, slowed thinking, and a tendency to wander) are similar to those of other dementias. However, compared with Alzheimer disease, vascular dementia tends to cause memory loss later and to affect judgment and personality less. People with vascular dementia may have particular difficulty planning and initiating actions, and their thinking may be noticeably slow.
Symptoms can vary depending on what part of the brain is destroyed. Usually, some aspects of mental function are not impaired because the strokes destroy tissue in only part of the brain. Thus, people may be more aware of their losses and more prone to depression than people with other types of dementia.
As more strokes occur and dementia progresses, people may have other symptoms due to the strokes. An arm or a leg may become weak or paralyzed. People may have difficulty speaking. For example, they may slur their speech. Vision may be blurred or partly or completely lost. Coordination may be lost, making walking unsteady. People may laugh or cry in appropriately. People may have difficulty controlling bladder function, resulting in urinary incontinence.
About 6 in 10 people die within 5 years after symptoms begin. It is often due to a stroke or heart attack.
The diagnosis is similar to that of other dementias (see Diagnosis).
Once dementia is diagnosed, doctors suspect vascular dementia in people who have risk factors for or symptoms of a stroke. Then doctors do a thorough evaluation to check for stroke (see Diagnosis). Computed tomography (CT) or magnetic resonance imaging (MRI) is done too check for evidence of a stroke. Results of these tests can support the diagnosis but are not definitive.
Treatment involves general measures to provide safety and support, as for all dementias (see Treatment). Treating diabetes, high blood pressure, and high cholesterol levels can help prevent and slow or stop the progression of vascular dementia. Stopping smoking is also recommended.
There is no specific treatment for vascular dementia. Sometimes cholinesterase inhibitors and memantine, the drugs used for Alzheimer disease, are given because some people with vascular dementia also have Alzheimer disease. For people who have had a stroke, doctors may recommend that they take aspirin, which can reduce the risk of another stroke. People with atrial fibrillation are given warfarin, an anticoagulant, to help reduce the risk of another stroke.
Last full review/revision July 2013 by Juebin Huang, MD, PhD