A new study from Washington University School of Medicine in St. Louis shows that race has an impact on the performance of four different experimental Alzheimer’s disease (AD) blood tests used to determine those who are in the early stages of the disease. The research, published in the journal Neurology on April 21, showed that three of the tests provided different results depending on if patients were Black or White.
However, the research showed that a fourth test was just as effective at revealing those in the early stages of Alzheimer’s, regardless of race, though it’s important to note that some of the researchers have connections to the company that offers the test in the US and Europe—C2N Diagnostics.
All four blood tests aim to identify those who may have Alzheimer’s earlier than then they normally would be through AD-related proteins found in patient’s blood. But, most research on such Alzheimer’s biomarkers has been done with mainly White participants, meaning tests based on these biomarkers may not be as effective at identifying the disease in other races, a press release on the study points out.
The Washington University School of Medicine in St. Louis research aimed to explore these concerns by assessing the performance of four blood tests in 76 matched pairs of African American and non-Hispanic White individuals (152 people in total).
They found that models predicting brain amyloidosis—the buildup of amyloid proteins in the brain that increases the risk of developing AD—that are based on plasma p-tau181, p-tau231, and neurofilament light chain (NfL) “may perform inconsistently and could result in disproportionate misdiagnosis of [African Americans].” On the other hand, models using a high-performance plasma Aβ42/Aβ40 assay “may provide an accurate and consistent measure of brain amyloidosis across [African American] and [non-Hispanic White] groups.”
Because the number of participants in the study was small, and several team members have connections to C2N Diagnostics, more research will be needed to confirm the results.
Look for a more in-depth report on the research in an upcoming issue of Diagnostic Testing & Emerging Technologies.