Posts Tagged ‘Screening tests’

Is It Smart to Be Tested for Dementia?

December 21, 2013

This blog post is derived from an article1 in the Health and Science section of the Washington Post. First of all, it is difficult to distinguish early dementia from mild cognitive impairment. These are those minor memory impairments we experience as we age. About one in five people older than 75 have such blips, and most cases never progress to dementia or Alzheimer’s. I would argue further that what are experienced as mild memory impairments might not even indicate mild cognitive impairment. We experience memory failures throughout our lives, but as we age we tend to attribute these failures as cognitive impairments that we fear will lead to dementia.

Moreover, some memory lapses that might seem to be like dementia might really be something else. Danish researchers reviewed the records of almost 900 patients thought to have dementia and found that 41% of them were in error. Alcohol abuse and depression were the most common reasons for the misdiagnoses.

Small strokes that damage the arteries in the brain can cause a type of memory loss known as vascular dementia which is not Alzheimer’s. Currently, an autopsy is the only definitive test of Alzheimer’s where the telltale amyloid plaques and neurofibrillary tangels are found. However, it should be realized that autopsies have been done and found these telltale indicators in individuals who never had any of the symptoms of Alzheimer’s or dementia while they were alive.

Recent tests using brain scanning can be misleading. If, after reading this blog post, you remain worried, the first step should be to see a gerontologist or neurologist specializing in dementia. The claim is that when a full evaluation is done by somebody who knows how to do it, the accuracy of the diagnosis is supposed to be in the range of 90%.

Absent these full evaluations done by specialists, routine screening tests can be quite misleading. Even with the best screening tests, about 20% of those who turn up positive for dementia don’t actually have it. Another 30% of the people who screen positive for dementia actually have only mild cognitive impairment, which won’t progress or cause them serious problems.

Moreover, there is even some question whether early diagnosis improves outcomes. It should be acknowledged that there is no cure or preventive vaccine for Alzheimer’s. All that drugs can do is to slow the progression of the disease. Here is where I part company with the experts. What is the point of prolonging the progression of the disease? To my mind, this is simply a matter of prolonging the suffering. Our medical system is not designed to give us the best medical care, but rather the most expensive medical care. There is a strong willingness to prolong suffering so doctors and drug companies can take advantage of their last opportunity to cash in!

Moreover, little is said about the concept of a cognitive reserve. The explanation for those who have the brain damage indicative of Alzheimer’s, but not the symptoms, have built of a cognitive reserve. This healthymemory blog is filled with posts and ideas on how to build a healthy memory and a cognitive reserve.

1Christie Aschwanden (2013). Just remember this: It may not be smart to get yourself tested for dementia. The Washington Post, December 17, E5.

© Douglas Griffith and, 2013. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and with appropriate and specific direction to the original content.