Causes, Symptoms and Life Expectancy of Vascular Dementia

Overview

Vascular dementia results from impaired blood flow to the brain. After Alzheimer's disease, it's one of the most common types of dementia, along with Lewy body dementia. Learning about vascular dementia—including its causes, symptoms and life expectancy—can help you know how to reduce your risk, as well as what to expect if you've been diagnosed with this type of dementia.

Vascular dementia was formerly called multi-infarct dementia because it was thought to only be caused by small strokes. However, the name was changed to vascular dementia to reflect the array of conditions that can impair the blood's ability to circulate to the brain. More recently, some physicians use the term vascular cognitive impairment, perhaps because it seems to capture the wide range, from mild to severe, of cognitive decline that vascular dementia can cause.

Vascular dementia often occurs alongside Alzheimer's disease, resulting in mixed dementia. Between 1% to 4% of people over the age of 65 have vascular dementia, and the risk of developing it increases dramatically with age. Vascular dementia is estimated to account for between 10 to 20 percent of all dementia cases.

Causes

Vascular dementia can occur either by a narrowing or a complete blockage of blood vessels in the brain, which deprives brain cells from nutrients and oxygen they need to function properly.

Vascular dementia often results from several small strokes that occur over time. It can also occur after a single major stroke, which is sometimes referred to as post-stroke dementia. Not all strokes lead to dementia, but up to one-third of those who have a stroke will develop dementia within six months.

Conditions like high blood pressure and diabetes that don't block blood vessels, but simply narrow them, can also lead to vascular dementia.

Risk Factors

People who develop vascular dementia often have a history of one or more of the following: heart attack, stroke, high blood pressure, diabetes, or high cholesterol. In particular, if an individual has a history of multiple strokes, the risk of developing vascular dementia increases with the number of strokes experienced over time.

Other factors that may increase your risk include smoking, atrial fibrillation, being male, having a family history of vascular dementia and being African American.

Symptoms

People with vascular dementia often display multiple cognitive problems, including memory impairment, aphasia, apraxia, agnosia, or problems with executive functioning.

In most cases, symptoms make it difficult to hold a job, carry out household responsibilities, or maintain social relationships. People with vascular dementia also experience neurological symptoms such as exaggerated reflexes, problems with walking and balance, and/or weakness in the limbs, hands, and feet. Depending on the individual and on the cause of the dementia, delusions, confusion, agitation, urinary problems, and/or depression can also accompany vascular dementia.

Interestingly, memory loss usually occurs later in vascular dementia compared to Alzheimer's disease. In vascular dementia, the first symptoms are often the neurological ones, such as problems with reflexes, walking, and muscle weakness. On the other hand, memory problems and behavioral symptoms are commonly the first issues noticed in Alzheimer's. Additionally, vascular dementia often progresses in a step-wise fashion. For example, the person will seem stable for a period of time, then suddenly get much worse, then continue to alternate between stable periods and sudden drops in functioning. Alzheimer's disease typically progresses in a more gradual, downward fashion.

Diagnosis

As with Alzheimer's disease, a complete diagnostic workup should be performed in order to rule out other possible causes of the person's symptoms. Vascular dementia is usually identified through imaging procedures, which can reveal strokes and narrowed or blocked arteries. Neuropsychological tests might also be conducted to determine the nature and extent of cognitive impairment.

Treatments

No drugs have been approved by the FDA specifically to treat vascular dementia, but medications approved to treat Alzheimer's sometimes help. Doctors often prescribe both a cholinesterase inhibitor (Aricept, Exelon, or Razadyne) and Namenda to treat vascular dementia.

Managing cardiovascular problems through medication and/or lifestyle changes may help slow the worsening of vascular dementia symptoms. It's critical to monitor blood pressure, pulse, cholesterol, blood sugar, and weight, all of which impact brain health and the ease of blood flow to the brain.

Behavior management strategies are also useful for handling the challenging behaviors that sometimes accompany vascular dementia.

Prognosis and Life Expectancy

Currently, there is no cure for vascular dementia. If the dementia was caused by multiple strokes, the person may get worse in a step-wise progression, where stable periods are interrupted by sudden downward episodes. Life expectancy for someone with vascular dementia is highly individual and depends on the nature of the cardiovascular problems that are causing the dementia, along with the person's age and other medical conditions.

_Sources:

Alzheimer's Association. Vascular Dementia. http://www.alz.org/dementia/vascular-dementia-symptoms.asp

_{American Psychiatric Association (2013). Diagnostic and statistical manual of mental disorders (DSM-5). Washington, DC: .}

_{Plassman, B. L., Langa, K. M., Fisher, G. G., Heeringa, S. G., Weir, D. R., Ofstedal, M. B., et al. (2007). Prevalence of dementia in the United States: The aging, demographics, and memory study. Neuroepidemiology, 29, 125-132.}

_{UC Memory Disorders Center. Vascular Cognitive Impairment.} http://memory.ucgardnerneuroscienceinstitute.com/understanding-memory-disorders/vascular-cognitive-impairment/