Conditions

Vascular Dementia


About Vascular Dementia

Vascular dementia is an overall term used to describe problems with reasoning, planning, judgment, memory and other thought processes caused by damage to the brain, due to impaired blood flow to your brain.

You can develop vascular dementia after a stroke blocks an artery in your brain, but strokes don't always cause vascular dementia. Whether a stroke affects your thinking and reasoning can be determined on your stroke's severity and location. Vascular dementia can also be a result of other conditions that damage blood vessels and reduce circulation, depriving your brain of vital oxygen and nutrients.

The risk of vascular dementia can also be raised by factors that increases the risk of heart disease or strokes such as diabetes, high blood pressure, high cholesterol and smoking. Controlling these factors may help lower the risk of developing vascular dementia.

Symptoms

Vascular dementia symptoms vary, depending on the part of your brain where blood flow is impaired. Symptoms often overlap with those of other types of dementia, especially those of Alzheimer's disease.

Vascular dementia signs and symptoms include:
  • Confusion
  • Trouble paying attention and concentrating
  • Reduced ability to organize thoughts or actions
  • Decline in ability to analyse a situation, develop an effective plan and communicate that plan to others
  • Difficulty deciding what to do next
  • Problems with memory
  • Restlessness and agitation
  • Unsteady gait
  • Sudden or frequent urge to urinate or inability to control passing urine
  • Depression or Apathy

Vascular dementia symptoms may be most clear-cut when they occur suddenly following a stroke. When changes in your thinking and reasoning seem clearly linked to a stroke, this condition is sometimes called post-stroke dementia. Changes in your thought processes occur in noticeable steps downward from your previous level of function, unlike the gradual, steady decline that typically occurs in Alzheimer's disease. But vascular dementia can also develop very gradually, just like Alzheimer's disease. What's more, vascular disease and Alzheimer's disease often occur together.

Causes

Vascular dementia results from damage to your brain's blood vessels, reducing their ability to supply your brain with the amounts of nutrition and oxygen it needs to perform thought processes effectively.

Common conditions that may lead to vascular dementia include:
  • Stroke - (infarction) blocking a brain artery. Strokes that block a brain artery usually cause a range of symptoms that may include vascular dementia. But some strokes don't cause any noticeable symptoms. These silent strokes still increase dementia risk. With both silent and apparent strokes, the risk of vascular dementia increases with the number of strokes that occur over time. One type of vascular dementia involving many strokes is called multi-infarct dementia.
  • Narrowed or chronically damaged brain blood vessels - Conditions that narrow or inflict long-term damage on your brain blood vessels also can lead to vascular dementia. These conditions include the wear and tear associated with aging, high blood pressure, abnormal aging of blood vessels (atherosclerosis), diabetes, and brain haemorrhage.

Risk Factors

The risk factors for vascular dementia are in general, the same as those for heart

disease and stroke. Risk factors for vascular dementia include:
  • Increasing age - Your risk of vascular dementia rises as you grow older. The disorder is rare before age 65, and the risk rises substantially by your 90s. History of heart attack, strokes or ministrokes, If you've had a heart attack, you may be at increased risk of having blood vessel problems in your brain. The brain damage that occurs with a stroke or a ministroke (transient ischemic attack) may increase your risk of developing dementia.
  • Abnormal aging of blood vessels (atherosclerosis) - This condition occurs when deposits of cholesterol and other substances (plaques) build up in your arteries and narrow your blood vessels. Atherosclerosis can increase your risk of vascular dementia by reducing the flow of blood that nourishes your brain.
  • High cholesterol - Elevated levels of low-density lipoprotein (LDL), the "bad" cholesterol, are associated with an increased risk of vascular dementia.
  • High blood pressure - When your blood pressure's too high, it puts more stress on blood vessels everywhere in your body, including your brain. This increases the risk of vascular problems in the brain.
  • Diabetes - High glucose levels damage blood vessels throughout your body. Damage in brain blood vessels can increase your risk of stroke and vascular dementia.
  • Smoking - Smoking directly damages your blood vessels, increasing your risk of atherosclerosis and other circulatory diseases, including vascular dementia.
  • Obesity - Being overweight is a well-known risk factor for vascular diseases in general, and therefore, presumably increases your risk of vascular dementia.
  • Atrial fibrillation - In this abnormal heart rhythm, the upper chambers of your heart begin to beat rapidly and irregularly, out of coordination with your heart's lower chambers. Atrial fibrillation increases your risk of stroke because it causes blood clots to form in the heart that can break off and go to the brain blood vessels.

Diagnosis

Because vascular cognitive impairment may often go unrecognized, many experts recommend professional screening with brief tests to assess memory, thinking and reasoning for everyone considered to be at high risk for this disorder. Individuals at highest risk include those who have had a stroke or a ministroke or have high blood pressure, high cholesterol, or other risk factors for heart or blood vessel disease.

If brief screening tests suggest changes in thinking or reasoning, a more detailed assessment is needed. Core elements of a workup for vascular dementia typically include:

  • A thorough medical history, including family history of dementia
  • Evaluation of independent function and daily activities
  • Input from a family member or trusted friend
  • In-office neurological examination assessing function of nerves and reflexes, movement, coordination, balance and senses
  • Laboratory tests including blood tests and brain imaging

According to a 2011 scientific statement issued by the American Heart Association (AHA) and the American Stroke Association (ASA), and endorsed by the Alzheimer's Association and the American Academy of Neurology (AAN), the following three criteria suggest the greatest likelihood that mild cognitive impairment (MCI) or dementia is caused by vascular changes:

  • The diagnosis of dementia or mild cognitive impairment is confirmed by neurocognitive testing, which involves several hours of written or computerized tests that provide detailed evaluation of specific thinking skills such as judgment, planning, problem-solving, reasoning and memory.
  • There is brain imaging evidence, usually with magnetic resonance imaging (MRI), showing evidence of either: a) A recent stroke, or b) Other brain blood vessel changes whose severity and pattern of affected tissue are consistent with the types of impairment documented in neurocognitive testing.
  • There is no evidence that factors other than vascular changes are contributing to cognitive decline. The guidelines also discuss cases where the diagnosis may be less clear-cut, such as the common situation where vascular changes coexist with brain changes associated with other types of dementia.