Advertisement

Blood Test Shows Early Promise in Identifying People at Risk for Dementia

Summary and Comment |
March 26, 2014

Blood Test Shows Early Promise in Identifying People at Risk for Dementia

  1. Brandy R. Matthews, MD

Markers of cell membrane integrity may be associated with preclinical Alzheimer disease.

  1. Brandy R. Matthews, MD

Current biomarkers for early Alzheimer disease (AD) include functional, structural, and protein neuroimaging as well as cerebrospinal fluid indices of amyloid beta and tau. Although these measures are increasingly valuable as predictors of conversion from amnestic mild cognitive impairment (aMCI) to AD, each is associated with variable accessibility, risk to patients, and cost to the healthcare system. These barriers have been prohibitive for large-scale assessment of potentially presymptomatic AD patients. In an attempt overcome these barriers, researchers collected peripheral blood samples from community-dwelling adults aged 70 and older. Three years later, 74 participants had aMCI or mild AD (46 incidental cases and 28 conversions during the study). The researchers compared blood test results for these individuals with those of participants who remained cognitively normal.

Ten different metabolites, including the cell membrane phospholipids phosphatidylcholine and acylcarnitine, were depleted in 53 of the participants who were cognitively impaired either at study entry or became so during the study. The same findings held when validating the 10-metabolite panel in the remaining study participants. The test had 90% accuracy in predicting which participants would develop aMCI or AD within 2 to 3 years.

— Adapted from a Physician's First Watch article published March 10, 2014.

Comment

This small study is provocative due to the relative ease with which peripheral blood may be accessed and systematically assessed in large populations. As the authors observe, this tool will require assessment in larger and more diverse populations before it is clinically relevant. However, these results are certainly encouraging and biologically plausible. Early intervention for neurodegenerative diseases such as AD is of critical importance to modify the disease course, and presymptomatic identification of disease would be potentially invaluable in this context.

  • Disclosures for Brandy R. Matthews, MD at time of publication Grant / research support National Institute on Aging

Citation(s):

Reader Comments (4)

Dr. V Kantariya MD Physician, Family Medicine/General Practice

We have a question "Why screen for something you cannot treat? " Sure enough :there is no certain cure for this disease. Preventive strategies are now feasible only on basis of early diagnosis of AD in clinically asymptomatic elders.

Clement Hanson DO, MPH Other

Screening tests for AD lack standardization, and those with more accuracy and validity (i.e., WAIS IV Testing) are costly. Insurance companies tend to delay authorization till more "evidence" exists. We need a "standard" test, other than "draw a clock" or "I'm giving you seven words to remember." Physician careers come to a screeching halt if they participate in neurocognitive testing that shows some neurocognitive decline despite having practiced decades in their specialty. There is a crying need for a standardized test for all fifty states.

DONALD CATINO Geriatrics, Australia

Why screen for something you cannot treat ?

michael gordon MD,MSc, FRCPC Physician, Geriatrics, Baycrest geriatric health sciences centre

I have to take issue with the conclusion,"Early intervention for neurodegenerative diseases such as AD is of critical importance to modify the disease course, and presymptomatic identification of disease would be potentially invaluable in this context." Other life style management and addressing vascular risk factors which we have been recommending for a very long time for heart and vascular brain disease, and maybe but only maybe brain stimulation with either commercial or non- commercial "brain games" I am not aware of anything that might change the course of this entitiy- whatever it is. On the other hand "labeling" is not without potentially serious adverse reactions in terms of life, insurance and other less tangible factors. Everyone knowing that the risk of cognitive decline is about 1 in 3 over age 80 should be doing all the "right things" anyway including preparing, wills, advance directive, commuinication with health care proxies to be and modifiyng diet, exercise programs and doing as many cross word puzzles that you can live with. One should not need a blood marker to get patients to do all these things---unless we can prove that knowing of an increased risk will promote better adherence to life-style changes and the love of cross word and other puzzles.

Your Comment

(will not be published)

Filtered HTML

  • Allowed HTML tags: <a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Do you have any conflict of interest to disclose?
CAPTCHA
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
Image CAPTCHA
Enter the characters shown in the image.

Vertical Tabs

* Required

Reader comments are intended to encourage lively discussion of clinical topics with your peers in the medical community. We ask that you keep your remarks to a reasonable length, and we reserve the right to withhold publication of remarks that do not meet this standard.

PRIVACY: We will not use your email address, submitted for a comment, for any other purpose nor sell, rent, or share your e-mail address with any third parties. Please see our Privacy Policy.

Advertisement
Advertisement
Advertisement