Seven-protein blood test could improve early testing for Alzheimer’s disease

Researchers have identified seven blood proteins that could help doctors to determine the biological stage of Alzheimer’s disease and make more informed treatment decisions

Researchers have identified seven proteins in the blood that could support more accurate tests for Alzheimer’s disease and help doctors to determine how far along the condition has progressed in a patient.

The study has indicated that a broader panel of biological markers could provide a clearer picture of the disease than a test for a single protein. The approach could improve patient assessment, inform treatment choices and help researchers to recruit suitable participants for clinical trials.

In the study researchers from the Sahlgrenska Academy, University of Gothenburg, Sweden, alongside collaborating institutions examined whether machine learning could identify a more informative combination of blood proteins. The team analysed proteomic data, which provided large-scale information about proteins in blood samples, to search for profiles associated with different disease stages.

Alzheimer’s disease is associated with two principal forms of abnormal protein accumulation in the brain. Amyloid-beta proteins collect to form plaques between nerve cells, while tau proteins assemble into thread-like structures known as neurofibrillary tangles within cells. These changes can begin to damage nerve cells years before any symptoms of dementia become apparent to the patient.

Diagnosis has historically depended heavily on changes in memory, reasoning and other cognitive abilities, which often emerge only after the underlying disease process has become established. Biomarker-based methods can detect biological signs at an earlier stage, but testing has been restricted largely because of the need to access specialist clinics equipped to collect cerebrospinal fluid or conduct positron emission tomography (PET) scans.

Blood tests for phosphorylated tau 217 (p-tau217) – a modified form of tau associated closely with Alzheimer’s disease – have made biomarker assessment more accessible. However, a p-tau217 test alone has had a limited ability to establish the disease stage or predict its course, particularly when compared with PET scans that can reveal tau deposits in the brain.

“We identified a panel of seven proteins – including p-tau217 – that could improve a blood test’s ability to determine whether a patient had a biological profile consistent with late-stage disease,” said Guglielmo Di Molfetta, a doctoral candidate in neurochemistry at the University of Gothenburg.

“This approach could produce more accurate screening results, which would be particularly valuable to guide treatment choices and recruit participants for clinical trials of future Alzheimer’s disease therapies,” he added.

The research team had assessed data from two independent international groups of participants. A novel immunoassay platform measured more than 120 proteins associated with inflammation, nerve cells and other biological processes in each blood sample.

The results showed that the addition of six proteins to p-tau217 significantly improved the test’s ability to identify advanced tau pathology among people with elevated levels of amyloid plaques. This distinction is important because tau pathology tends to correspond more closely than amyloid burden with disease severity and cognitive impairment.

The researchers also said the seven-protein panel could offer a practical alternative to tau PET for disease staging in some clinical and research settings. Although it would not necessarily replace brain scans, it could help specialists to decide which patients required further assessment and who might be suitable for treatments or clinical trials aimed at a particular disease stage.

Further research will be required to validate the panel in larger and more diverse patient populations and establish how it could perform in routine clinical practice.

For further reading please visit: 10.1001/jamaneurol.2026.2650