New multi-protein blood test accurately detects late-stage Alzheimer's disease

Researchers have identified seven proteins in the blood that could enable better blood tests for Alzheimer's disease. A study shows that using a broader panel of markers provides a clearer picture of the disease and allows for more accurate future treatment choices.

In Alzheimer's disease, amyloid plaques form in the brain, followed by thread-like structures made of the protein tau, changes that both have toxic effects on the brain's nerve cells years before dementia symptoms appear.

Historically, diagnosis has primarily relied on cognitive changes, which manifest at a later stage of the disease. Biomarker-based diagnostics were initially limited to specialized clinics capable of performing cerebrospinal fluid sampling or PET scans.

New blood-based tests, such as p-tau217, have improved accessibility. However, their ability to determine the disease stage and predict disease progression remains limited, especially when compared to PET scans.

Significantly better capability

In the current study, published in the journal JAMA Neurology, researchers at the University of Gothenburg and their colleagues investigated whether applying machine learning to blood proteomics data, large-scale information on all proteins in the blood, could identify new biomarker profiles to improve the assessment of disease stage.

The researchers used two independent international cohorts with data from a novel immunoassay platform that measures more than 120 inflammation and neuronal markers in a single blood sample.

The study results show that including additional proteins significantly improved the ability of p-tau217 to predict advanced tau pathology in individuals with elevated levels of amyloid plaques.

Treatment choices and research

According to the researchers, the results indicate that a multi-protein-based approach could be a viable alternative to staging via tau-PET in clinical or research settings.

We identified a panel of seven proteins, including p-tau217, that could improve the blood test's ability to determine when a patient exhibits a disease profile corresponding to a late stage. This could yield better screening results, which is particularly valuable for guiding treatment choices and recruitment for clinical trials of future treatments for Alzheimer's disease."

Guglielmo Di Molfetta, doctoral student in neurochemistry, University of Gothenburg