When it comes to Alzheimer's, one of the biggest hurdles patients face is actually testing and getting a confirmed diagnosis for the disease. Tried and true methods that include brain imaging with MRI scanners, and spinal fluid tests, can be incredibly expensive. A lot of communities throughout the world don’t even have access to these tools. This creates an accessibility nightmare for folks who potentially have Alzheimer’s—and results in people of color being disproportionately impacted.
That’s why researchers have long sought new ways to diagnose the neurodegenerative disease. One of the methods involves blood tests, which could potentially reveal specific biomarkers that indicate Alzheimer’s in an accessible and cost-effective way. But many of them have so far failed to be a reliable diagnostic for the disease due to their inability to pick up on neurodegeneration biomarkers—that is, until now.
In a study published on Dec. 27 in the journal Brain, researchers at the University of Pittsburgh have developed a new test for Alzheimer’s disease that can pick up on neurodegeneration via a blood sample. The study’s authors claim that the new method outperforms other blood tests for Alzheimer’s and could make diagnosing the disease more accessible while cutting down on costs.
“At present, diagnosing Alzheimer’s disease requires neuroimaging,” Thomas Karikari, assistant professor of psychiatry at Pitt and senior author of the study, said in a statement. “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.”
Diagnosing Alzheimer’s disease involves finding three indicators in patients: amyloid plaques and tau tangles, which are abnormal proteins in neurons; and brain neurodegeneration, which is when nerve cells lose function and die. Spinal fluid tests and brain imaging are typically used to find all of these indicators. However, this creates a fairly big hurdle for doctors and patients alike in terms of accessibility—which is why blood tests could present a good alternative.
However, the most common blood diagnostics are also fairly limited as they can only pick up on a few of the biomarkers (namely amyloid plaque and tau tangles). That’s why the Pitt researchers decided to focus on a biomarker dubbed “brain-derived tau” (BD-tau), which is not only detectable in blood tests but strongly correlates with Alzehiemer’s-related neurodegeneration in spinal fluid.
These findings can lead to greater accessibility, particularly to communities of color that are disproportionately under diagnosed when it comes to Alzeheimer’s disease. Karikari believes that this reinforces the “huge need for diversity in clinical research, not just by skin color but also by socioeconomic background” and also more accessible diagnostic testing.
“To develop better drugs, trials need to enroll people from varied backgrounds and not just those who live close to academic medical centers,” Karikari said. “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.”