Scientists believe a blood test that can predict dementia up to 15 years before symptoms begin could change the lives of thousands of people.
Researchers found 11 protein “biomarkers” in the blood of people later diagnosed with Alzheimer’s and similar diseases, allowing them to predict the conditions with more than 90 percent accuracy.
It means a simple blood test could replace the expensive, time-consuming and invasive tests currently available for dementia patients, more than a third of whom are never diagnosed.
It is hoped that the proteins could also help guide the development of new drugs to slow or even reverse dementia.
Professor Jianfeng Feng, from the University of Warwick, said blood tests could be “seamlessly integrated” into the NHS and used by GPs to assess patients.
Researchers found 11 protein “biomarkers” in the blood of people later diagnosed with Alzheimer’s and similar diseases, allowing them to predict the conditions with more than 90 percent accuracy. It means a simple blood test could replace the expensive, time-consuming and invasive tests currently available for dementia patients, more than a third of whom are never diagnosed.
It is currently believed that around 900,000 Britons suffer from this memory-robbing disorder. But scientists at University College London estimate this figure will rise to 1.7 million within two decades as people live longer. It marks a 40 percent increase from the previous forecast in 2017.
He said: “This is very important to detect middle-aged and older people within the community who are at high risk of dementia.”
He added that future drugs could be developed that interact with the proteins identified in the study, possibly offering new treatments.
Early diagnosis is vital for patients with dementia. New drugs such as lecanemab and donanemab, which have not yet been approved for use in the UK, can slow the progress of Alzheimer’s, but only if the disease is detected early.
Currently, dementia testing involves lumbar punctures and PET scans, which use a radioactive substance to look for changes in brain tissue.
They are invasive, expensive and can be time-consuming as the NHS has a limited number of PET scanners.
It is hoped that the blood test could revolutionize the diagnosis of dementia and lead to much earlier preventive treatment, giving patients a better quality of life for longer.
However, while the research is promising, any test must go through regulatory approval before it can be used in a healthcare setting.
Dr Sheona Scales, research director at Alzheimer’s Research UK, described the findings as “fantastic progress”.
He said: “It is crucial to find better and more accessible ways to diagnose dementia.”
‘Only two in three people with dementia in the UK receive a formal diagnosis, and current options are expensive and invasive.
«New treatments such as lecanemab, if approved, will only be effective if they are administered to people in the early stages of Alzheimer’s.
‘At the moment, very few people have access to the specialized tests that would be necessary.
But they can also be a sign of dementia, the memory-robbing disease that affects almost a million Britons and seven million Americans.
‘Blood tests could enable early diagnosis and show great promise, but so far none have been validated for use in the UK.
“We are in the process of funding research to provide the tests the NHS would need to move forward with blood tests to diagnose Alzheimer’s disease.”
Dr Amanda Heslegrave, from the UK Dementia Research Institute at University College London, said further studies could allow doctors to identify the type of dementia a patient will develop, allowing them to tailor their treatment.
He added: “As disease-modifying treatments are close to being approved in the UK, we need to develop a screening strategy.”
The study, published in the journal Nature Aging, analyzed blood samples from 52,645 people taken between 2006 and 2010.
The 1,417 who developed dementia had telltale protein biomarkers in their blood up to 15 years earlier.
The discovery was aided by a type of artificial intelligence known as machine learning.
Researcher Wei Cheng, from Fudan University in China, said: “This newly developed protein-based model is obviously a breakthrough.”
“Proteomic biomarkers are easily accessible and non-invasive, and can substantially facilitate the application of large-scale population screening.”