Are blood tests the future of diagnosing Alzheimer’s disease?

The possibility of using blood tests as part of the diagnosis pathway has been an exciting area of research for some time. Scientists have long searched for biomarkers – biological clues that we can find outside the brain, that tells us how the brain is changing.

In the past few years, we’ve seen real advances in detecting proteins in the blood that build up in the brain during Alzheimer’s disease. Now scientists are using this technology to develop blood tests that could help with diagnosing dementia.

Currently, people are diagnosed by using tests that measure memory and thinking abilities and brain scans, and sometimes a lumbar puncture. These can be time-consuming, uncomfortable, and scans are not available at all dementia services in the UK.

Too many people in the UK are left anxiously waiting for a diagnosis for dementia. The process can take up to two years, and more than four years if they are under 65.

This highlights an urgent need for the NHS to improve how it diagnoses people with symptoms of dementia, and introducing a blood test could be a crucial part of that evolution.

Dr Ashvini Keshavan and Prof Jonathan Schott are leading a study based at University College London that will focus on validating a promising blood test for Alzheimer’s disease. This is part of the £5million Blood Biomarker Challenge awarded to Alzheimer’s Research UK and Alzheimer’s Society by the People’s Postcode Lottery in collaboration with the National Institute for Healthcare and Research, and the Gates Ventures (the private office of Bill Gates).

Their study, known as the ‘ADAPT study’, is investigating a blood test to measure levels of a protein called p-tau217. P-tau217 increases in the blood to reflect the  build-up of the protein tau in the brain during the development of Alzheimer’s disease.

“Ideally we need to have biomarkers that are accurate, easily scalable and cheap, in order to improve dementia diagnosis. Blood biomarkers aim to meet this need, at several levels of the pathway to treatment.” Dr Ashvini Keshavan, lead researcher on the ADAPT study.

Ashvini and colleagues will carry out a clinical trial to see whether measuring p-tau217 in the blood increases the rate of diagnosis for Alzheimer’s disease in people with early dementia. It will also involve those with mild, progressive memory problems.

If successful, this project could revolutionise the way dementia is diagnosed, and will lead to a blood test for diagnosing Alzheimer’s disease being used in the NHS within the next 5 years.

You can hear Ashvini speak about her work in the recording of our online discussion event Are blood tests the future of dementia diagnosis?