Neuroscientists developed a blood-based biomarker for Alzheimer's diagnosis

A significant step toward improved accessibility.
Mert Erdemir
Amyloid plaques in Alzheimer's disease stock photo.
Amyloid plaques in Alzheimer's disease stock photo.

Artur Plawgo/iStock 

Neuroscientists from the University of Pittsburgh School of Medicine developed a new test to identify a sign of Alzheimer's disease neurodegeneration in a blood sample, according to a press release.

Called "brain-derived tau" (BD-tau), the biomarker is specific to neurodegenerations related to Alzheimer's disease, and it reportedly outperforms currently used blood diagnostic tests.

"At present, diagnosing Alzheimer's disease requires neuroimaging," said senior author Thomas Karikari, Ph.D., assistant professor of psychiatry at Pitt. "Those tests are expensive and take a long time to schedule, and a lot of patients, even in the U.S., don't have access to MRI and PET scanners. Accessibility is a major issue."

Paving the way for a more accessible diagnosis method

Currently, clinicians employ guidelines established in 2011 by the National Institute on Aging and the Alzheimer's Association to diagnose Alzheimer's disease. However, these guidelines, called the AT(N) Framework, require identifying three separate components of Alzheimer's pathology — the presence of amyloid plaques, tau tangles, and neurodegeneration in the brain — via imaging or cerebrospinal fluid (CSF) analysis.

Since current procedures have economic and practical limitations, there is a need for simple and accurate AT(N) biomarkers in blood samples, the collection of which is less intrusive and takes fewer resources. Karikari states that the development of simple tools for Alzheimer's disease diagnosis is a crucial step toward improved accessibility.

"The most important utility of blood biomarkers is to make people's lives better and to improve clinical confidence and risk prediction in Alzheimer's disease diagnosis," Karikari said.

Planning larger-scale clinical trials

Scientists expect that monitoring BD-tau blood levels will enhance the clinical trial design and enable the screening and recruitment of patients from communities that have been excluded from research cohorts.

"There is a huge need for diversity in clinical research, not just by skin color but also by socioeconomic background," said Karikari.

"To develop better drugs, trials need to enroll people from varied backgrounds and not just those who live close to academic medical centers. A blood test is cheaper, safer, and easier to administer, and it can improve clinical confidence in diagnosing Alzheimer's and selecting participants for clinical trial and disease monitoring."

For the future, the research team is planning larger-scale clinical trials of blood BD-tau on a wider range of participants, including those from diverse racial and ethnic backgrounds.

Furthermore, these trials will involve both older persons who have no biological signs of Alzheimer's disease and those who are in different stages of the disease. These efforts will pave the road for BD-tau to be commercially available for wider clinical and prognostic usage, ensuring that the biomarker results are generalizable to persons of all backgrounds.