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Using Retinal Imaging to Study Dementia
09:17

Using Retinal Imaging to Study Dementia

Published on: November 6, 2017

Down's syndrome, dementia and macrocytosis

Vee Prasher1, Jay Viswanathan2, Roger Holder3

  • 1Monyhull Hospital,Monyhull Hall Road,Kings Norton,Birmingham B30 3QQ,England.

Irish Journal of Psychological Medicine
|November 17, 2018
PubMed
Abstract

Insights

Raised red blood cell size (macrocytosis) may help diagnose Alzheimer's disease (AD) in individuals with Down syndrome (DS). Further elevated mean corpuscular volume (MCV) correlated with AD, suggesting MCV as a potential diagnostic aid.

Area of Science:

  • Neurology
  • Hematology
  • Genetics

Background:

  • Alzheimer's disease (AD) lacks definitive peripheral biomarkers.
  • Down syndrome (DS) individuals have a high prevalence of AD pathology.
  • Macrocytosis, indicated by elevated mean corpuscular volume (MCV), is common in DS.

Purpose of the Study:

  • To investigate macrocytosis as a potential peripheral biomarker for AD in adults with DS.
  • To explore the association between elevated MCV and clinically diagnosed AD in the DS population.

Main Methods:

  • A longitudinal study over five years.
  • Involved 150 adults with Down syndrome.
  • Measured mean corpuscular volume (MCV) levels.

Main Results:

  • A statistically significant association was found between a further elevated MCV and clinically diagnosed AD in adults with DS.
  • Higher MCV levels were linked to AD diagnosis within the DS cohort.

Conclusions:

  • Further research into macrocytosis in DS could elucidate AD's biological mechanisms.
  • MCV measurement is recommended for DS individuals with dementia.
  • Significantly elevated MCV (males >97fl, females >99fl) may aid clinical diagnosis but is not a standalone diagnostic test for AD in DS.

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