Thousands of Britons to receive cheap blood tests for Alzheimer’s in landmark NHS trial

Thousands of people in England will be offered a low‑cost blood test for Alzheimer’s disease as part of a large clinical trial aimed at speeding diagnosis and improving care, researchers said.

The study, led by University College London (UCL), will enrol about 1,100 adults from 20 areas of the UK who have reported memory or cognitive symptoms to their general practitioner and may be in the early stages of dementia. The trial will use a blood assay that measures phosphorylated tau 217 (p‑tau217), a protein marker that research suggests indicates the presence of both amyloid and tau pathology in the brain, hallmarks of Alzheimer’s disease.

Recruitment at the first site, Essex Partnership University NHS Foundation Trust, began late last month. Participants will be randomly assigned to receive their blood test results after three months or after 12 months, allowing investigators to compare whether earlier identification of Alzheimer’s pathology changes clinical management, access to services, and quality of life.

The trial is part‑funded by the People’s Postcode Lottery and is intended to assess not only the diagnostic performance and cost of the test but also its real‑world impact on patient care. Researchers will track how the test results influence referrals, treatments, and support services, and whether earlier knowledge of pathology affects patients’ well‑being.

"Too often, dementia is diagnosed late, limiting access to support, treatment, and opportunities to plan ahead," said Professor Fiona Carragher, chief policy and research officer at Alzheimer’s Society. "For many across the UK, getting that diagnosis remains a major challenge—one that it will take society, researchers and governments working together to fix. This trial marks a critical step towards that. Blood tests could offer a faster and more accessible route to diagnosis."

UCL neurologist Jonathan Schott, chief medical officer at Alzheimer’s Research UK, said that after decades of research there is now strong evidence that blood tests can provide information comparable to gold‑standard diagnostics such as PET scans and cerebrospinal fluid analysis obtained via lumbar puncture, while being cheaper and more accessible.

"Currently only about 2 percent of people diagnosed with Alzheimer’s have access to one of these gold‑standard diagnostic tests," Schott said. "While identifying Alzheimer’s disease early and accurately is already important for enabling access to current therapies and planning care, it will become even more critical as a new generation of treatments emerge that can slow down the decline of memory and thinking. Timely diagnosis will be key to ensuring these advances reach the people who need them most."

The p‑tau217 marker is being studied because significant accumulations of amyloid plaques and tau tangles in the brain are believed to underlie the memory loss, declines in thinking and reasoning, and language problems that worsen over time for people with Alzheimer’s disease.

About 944,000 people in the UK are estimated to be living with dementia, according to recent figures cited by researchers, and UCL scientists project that number could rise to 1.7 million within two decades as the population ages, a roughly 40 percent increase on previous forecasts. Alzheimer’s disease accounts for about six in 10 dementia cases. Estimates suggest that up to one in three people living with dementia in England have not yet received a formal diagnosis.

The trial will test whether a widely deployable blood‑based screening approach can reduce diagnostic delays that currently rely on cognitive tests, neuroimaging, or invasive lumbar punctures. The investigators will also evaluate the cost implications for the National Health Service, where access to advanced diagnostic tests has been limited.

Dementia is already a major cause of death and disability in the UK: analysis cited by the trial team showed 74,261 deaths attributed to dementia in 2022, up from 69,178 the previous year, making it a leading cause of mortality.

The study’s outcomes are intended to inform NHS diagnostic pathways and policy decisions on wider use of blood tests for Alzheimer’s disease. The trial team emphasized that the research seeks to establish whether earlier biochemical detection of Alzheimer’s pathology translates into measurable benefits for patients and families in everyday clinical settings.