Blood Proteins Can Predict Dementia In People With Mild Cognitive Impairment

A number of proteins in the blood could predict the transition between mild cognitive impairment (MCI) and dementia, according to research published today (Tuesday 8 July 2014). Using blood samples from over 1,000 people and MRI scans from 473 people, researchers at King’s College London have identified sixteen proteins which were implicated in the development of the Alzheimer’s disease and could be used as markers for dementia even before full symptoms develop.

The study looked at samples from 476 people with Alzheimer’s disease, 220 people with mild cognitive impairment and a control group of 452 older people without dementia. The academics found a number of proteins – including the protein clusterin – which were associated with higher brain atrophy amongst those with MCI or Alzheimer’s. Additionally, the researchers identified six proteins which were associated with greater atrophy of the hippocampus, which is one of the first brain regions to be affected by Alzheimer’s disease. Ten proteins were found to be predictive of the conversion between MCI and Alzheimer’s.

Alzheimer’s Society comment:

‘Finding a way to detect dementia before symptoms develop would revolutionise research into the condition. Most of the blood proteins identified here are not new to the dementia community, but this study has brought them together into a protein set that seems to predict disease severity. Although it needs to be validated in a larger group of people, their modelling work shows a set of 10 proteins can predict which people with mild cognitive impairments will progress to developing dementia.

‘However, this research does not mean that a blood test for dementia is just around the corner. These ten proteins can predict conversion to dementia with less than 90% accuracy, meaning one in ten people would get an incorrect result. Therefore, accuracy would need to be improved before it could be a useful diagnostic test. Only through further research will we find answers to the biggest questions around dementia, so we will watch the progress of this study with interest.’

Dr James Pickett,
Head of Research
Alzheimer’s Society