A revolutionary finger-prick blood test, which can be administered at home, could soon transform how dementia is diagnosed in the UK, potentially unlocking vital treatments for hundreds of thousands of people.
The Challenge of Current Diagnosis Methods
Currently, around 900,000 people in the UK are thought to be living with dementia, a figure scientists from University College London estimate will soar to 1.7 million within two decades. Alarmingly, about a third of those with the condition lack a formal diagnosis, which bars them from accessing new, potentially life-changing drugs.
The existing pathway to diagnose Alzheimer's disease, the most common form of dementia, relies on expensive brain scans and invasive spinal fluid tests. These methods are often inaccessible, leading to critical delays. Professor Fiona Carragher of Alzheimer's Society highlighted the issue, stating: 'Too often, dementia is diagnosed late, limiting access to support, treatment, and opportunities to plan ahead.'
A Promising New Biomarker
In a landmark study published in the journal Nature, researchers from the University of Gothenburg in Sweden have pioneered a new approach. They focused on measuring levels of a specific protein called p-tau127 in the blood.
In Alzheimer's patients, harmful proteins called amyloid and tau accumulate in the brain. P-tau127 is a crucial biomarker because it reflects the presence of both. The team analysed blood from over 330 participants, collecting samples via a simple finger-prick that were then dried on a card.
The results were striking: the protein levels from the finger-prick test closely matched those from standard venous blood draws. Furthermore, the test could identify Alzheimer's-related changes in spinal fluid with 86 per cent accuracy. The research also successfully measured two other markers, GFAP and NfL.
Implications for UK Healthcare and Future Trials
Perhaps the most significant finding was that patients could successfully administer the test themselves without a healthcare professional. The researchers concluded this method 'has the potential to substantially broaden our understanding of the prevalence and distribution of Alzheimer's across the general population.'
This breakthrough aligns with a major UK trial announced recently. Researchers from University College London are launching a study involving 1,100 people across 20 UK areas, using blood tests to detect dementia-linked proteins in individuals who have reported memory loss to their GP. Recruitment at the first site in Essex began in August 2025.
While experts have welcomed the development, noting it could offer a faster, cheaper, and more accessible route to diagnosis, they caution that the use of dried blood samples requires more research before widespread rollout in hospitals. With dementia now the nation's biggest killer, claiming 74,261 lives in 2022, such an accessible screening tool is becoming increasingly vital.
