Large-scale study validates simple blood test for dementia.

Scientists at Rigshopitalet, Herlev Hospital and the University of Copenhagen identify a new biomarker that can predict the risk of developing dementia by way of a simple blood test. In the long term, this could mean better prevention and thus at least postponement of the illness and at best evading the development all together. The study is published in the journal, Annals of Neurology.

As opposed to cardiovascular diseases, where the level of cholesterol in the blood indicates the risk of cardiac arrest, there are no such trustworthy markers in human blood in terms of diagnosing the risk of dementia setting in. However, the researchers have now identified a new biomarker, measurable in a simple blood test, which will help predict the onset of dementia.

The blood test will help provide a more precise risk evaluation of a person’s risk of developing dementia later in life. Thus the people at the greatest risk of developing the illness are more easily identified than at present.  Researchers hope that with time, this new blood test will be applicable in clinical practice.  The team state that the blood test will enable an earlier and more focused prevention effort, thus prolonging the onset of the illness and raising the individual’s quality of life.

Globally, in excess of 35 million people suffer dementia, in Denmark alone, there are approx. 80,000 who suffer this illness. Prevalence increases in step with aging, and as people’s life years are continually on the rise in most countries, there is also an increasing need to be able to identify the people who are at the greatest risk of suffering dementia.

In the study, researchers show that a low level of the biomarker apolipoprotein E in the blood, increases the risk of developing dementia in the future. This was revealed in comprehensive studies of the general public, the Herlev-Oesterbro Study and the Oesterbro Study, involving 76,000 people.

The healthy brain consists of millions of interconnected nerve cells. The brain in a person suffering dementia is very different. The well-organised, structured coordination of nerve cells is intersected by, among other things, senile plaques that consist of the viscous compound, β-amyloid.

In the current study the low level of apolipoprotein E in the blood most likely reflects a low level of apolipoprotein E in the brain, and this indicates that the viscous compound, β-amyloid, is less effectively removed. Thus the study’s results underpin a biological mechanism.

The researchers explain that over time, this increased biological knowledge about dementia can constitute a point of departure for the development of new drugs.

Source:  University of Copenhagen

Credit:  CSIRO and the Walter and Eliza Hall Institute of Medical Research (WEHI) 2015.
Credit: CSIRO and the Walter and Eliza Hall Institute of Medical Research (WEHI) 2015.