Vascular Dementia (VaD), from the Alzheimer's Society o...

Vascular Dementia (VaD), from the Alzheimer's Society of Canada

Vascular Dementia

Introduction

Dementia is a syndrome consisting of a number of symptoms that include loss of memory, judgment and reasoning, and changes in mood, behaviour and communication abilities. These symptoms may affect a person's ability to function at work, in social relationships or in day-to-day activities. Sometimes symptoms of dementia can be caused by conditions that may be treatable, such as depression, thyroid disease, infections or drug interactions. However, if the symptoms are not treatable and progress over time, they may be due to damage to the nerve cells in the brain.

Alzheimer's disease is the most common form of dementia. It is a disease of the brain, characterized by deterioration of thinking ability and of memory, caused by the progressive death of brain cells. Alzheimer's disease accounts for approximately 64% of all dementias diagnosed in Canada. The features of Alzheimer's disease include a gradual onset and continuing decline of memory, as well as changes in judgment or reasoning, and ability to perform familiar tasks. Other dementias include Vascular Dementia, Lewy body Dementia, Frontotemporal Dementia and Creutzfeldt-Jakob Disease.

Sometimes a person may have symptoms such as sudden onset of memory loss, behaviour changes, or difficulties with speech and movement. These symptoms may suggest a dementia other than Alzheimer's disease. Lewy body Dementia is one of these dementias. A person should seek a thorough medical assessment if any of these symptoms are present.

Regardless of the type of dementia, individuals are encouraged to obtain information and support from the Alzheimer Society.

What is Vascular Dementia?

Vascular Dementia (VaD), also called multi-infarct dementia, occurs when the cells in the brain are deprived of oxygen. A network of blood vessels called the vascular system supplies the brain with oxygen. If there is a blockage in the vascular system, or if it is diseased, blood is prevented from reaching the brain. As a result, cells in the brain die, leading to the symptoms of dementia. After Alzheimer's disease, VaD is the second leading cause of dementia.

When Alzheimer's disease and VaD occur at the same time, the condition is called mixed dementia.

How does Vascular Dementia affect the person?

Stroke and Vascular Dementia

Stroke is a common cause of VaD. A stroke occurs when blood flow in the brain is blocked. When this occurs, the brain cells are deprived of oxygen and die. Strokes can be large or small, and can have a cumulative effect (each stroke adding further to the problem). Depending on the specific brain areas deprived of oxygen, strokes can affect the person's ability to walk, can cause weakness in an arm or leg, slurred speech or emotional outbursts. VaD may also develop.

VaD usually has a sudden onset. Impairment may occur in steps, where functioning can deteriorate, stabilize for a time and then deteriorate again. The cognitive symptoms may vary, affecting some areas of the brain more or less than others (e.g., language, vision or memory).

Binswanger's disease

Binswanger's disease is a less common form of VaD that is caused by damage to blood vessels deep in the brain's "white matter." High blood pressure plays an important role in Binswanger's disease.

How is Vascular Dementia assessed?

If VaD is suspected, the doctor will often order scans of the brain in order to check for blockages or narrowing of blood vessels in the brain.

What are the risk factors for Vascular Dementia?

Both men and women can be affected by VaD. Risk factors for VaD include:

* over age 65
* having high blood pressure (hypertension)
* heart disease
* diabetes

Smoking, being overweight, having elevated cholesterol levels and a family history of heart problems may also increase the risk of stroke, which increase the risk of VaD. Mini-strokes (sometimes referred to as transient ischemic attacks or TIAs) are warning signs that a stroke may be imminent. Temporary loss of vision, speech, strength or brief episodes of numbness may indicate a TIA.

Knowing the risk factors for VaD is important because often they may be treated to reduce the risk of stroke. Risk factors can be reduced by adopting a healthy lifestyle that includes regular physical activity, eating well, avoiding smoking and reducing stress. Medications can control high blood pressure, diabetes and heart disease.

Is there treatment?

After a person has a stroke, medication may be prescribed to improve blood flow to the brain and reduce the risk of further stroke. A person may also benefit from different therapies to help with movement and speech, such as physiotherapy, occupational therapy or speech therapy. Aside from the treatment of the underlying causes of VaD such as hypertension, high cholesterol and diabetes, some physicians routinely recommend the use of medications called cholinesterase inhibitors.

For more information:

* Call your local Alzheimer Society.
* Visit the Heart and Stroke Foundation website: http://ww2.heartandstroke.ca/splash/

[The contents of this document are provided for information purposes only, and do not represent advice, an endorsement or a recommendation, with respect to any product, serve or enterprise, and/or the claims and properties thereof, by the Alzheimer Society of Canada. The Information Sheet is not intended to replace clinical diagnosis by a health professional.]