Fingerprick Blood Test Accurately Assesses Signs of Alzheimer's, Researchers Say

TUESDAY, Jan. 6, 2026 (HealthDay News) — A mail-in blood test accurately detects markers linked to Alzheimer’s disease, potentially making the degenerative brain condition easier to diagnose and research, a new study says.

The finger-prick test accurately measures blood levels of tau proteins, glial fibrillary acidic proteins and neurofilament light fragments, researchers reported Jan. 5 in the journal Nature Medicine.

All are hallmarks of brain damage associated with Alzheimer’s, researchers said.

The test is still years away from clinical use among regular patients, but currently could help fuel research efforts into Alzheimer’s, researchers said.

“Ultimately, we are moving toward a pathway of treating people for Alzheimer’s disease before symptoms emerge,” said senior researcher Nicholas Ashton, senior director of Banner Health’s Fluid Biomarker Program in Sun City, Arizona.

“If this trajectory continues, we will need innovative ways to identify eligible individuals who are not routinely presenting in clinical settings,” Ashton said in a news release. “This work represents one such approach in that direction and further validation remains.”

For the study, researchers analyzed dried blood samples provided by 337 people. Participants provided a few drops of blood, which were dried on a card before lab analysis.

The lab work looked at blood levels of: 

• Phosphorylated tau proteins, which form toxic clumps in the brains of Alzheimer’s patients

• Protein fragments of neurofilament light chain (NfL), which are released from damaged or dying brain cells

• Glial Fibrillary Acidic Protein (GFAP), a protein produced by cells that heal and protect neurons in the brain and spinal cord

The pin-prick samples showed levels of tau proteins that closely matched those found in standard blood and spinal fluid tests.

The dried blood samples also accurately captured people’s levels of GFAP and NfL, researchers said.

This simple technique could make it easier to perform large-scale Alzheimer’s studies by enabling remote participation, researchers said.

“What excites me most is the democratization of biomarker research this enables,” Anne Corbett, a professor of dementia research at the University of Exeter in the U.K., said in a news release. “We’re moving toward a future where anyone, anywhere, can contribute to advancing our understanding of brain diseases. This isn’t just a technical advancement — it’s a paradigm shift in how we conduct neuroscience research.”

This method also could help research efforts associated with other brain diseases, including Parkinson’s disease, multiple sclerosis, Amyotrophic Lateral Sclerosis (ALS) and brain injuries, researchers said.

More information

The Alzheimer’s Association has more on the biomarkers of Alzheimer’s disease.

SOURCE: Banner Health, news release, Jan. 5, 2026