A MAJOR UK trial is offering 1,100 individuals with suspected dementia a blood test for Alzheimer’s disease, aiming to raise diagnostic accuracy from 70% to over 90%. The test, used alongside cognitive assessments, could help revolutionise early diagnosis and access to treatment for patients nationwide.
Alzheimer’s disease, the UK’s most common dementia, is typically confirmed only through costly and invasive PET scans or lumbar punctures. These “gold-standard” methods are not available to most patients, leaving cognitive tests, often inaccurate in early disease stages, as the primary tool. Researchers at University College London are now trialling a blood test in 20 memory clinics across the country, analysing the biomarker p-tau217, which reflects the build-up of rogue amyloid and tau proteins in the brain – hallmarks of Alzheimer’s that can trigger symptoms years before diagnosis.
The ADAPT study is recruiting 1,100 participants living with memory symptoms or mild dementia from a broad range of backgrounds. Half will receive their blood test results within three months of their first assessment, while the other half will receive results after 12 months. The researchers will track whether earlier access to biomarker testing speeds up the diagnostic process, influences investigations, and improves patient care decisions. The trial also aims to evaluate how the new test impacts quality of life and whether it can be usefully and equitably integrated within NHS memory services. At present, just 2% of those diagnosed with Alzheimer’s gain access to confirmatory PET scans or lumbar punctures.
If successful, the blood test could become a routine part of diagnosis, offering cost-effective, earlier, and fairer access to support and future treatment, especially as new drugs for early Alzheimer’s near approval. This marks a critical step for families affected by dementia and for clinicians seeking more reliable tools in daily practice.
Reference
Alzheimer’s Society. UK trial launches to transform Alzheimer’s diagnosis with simple blood test. Available at: https://www.alzheimers.org.uk/news/2025-09-09/uk-trial-alzheimers-diagnosis-blood-test-launch. Last accessed: 11 September 2025.
