A groundbreaking study by the Foundation for the National Institutes of Health (FNIH) Biomarkers Consortium has revealed that certain blood tests are now accurate enough to be used in clinical settings for detecting Alzheimer’s disease. This new research suggests these blood tests could replace more invasive procedures like spinal taps and brain scans for many patients experiencing cognitive impairment.

Blood Tests Show Accuracy Comparable to Traditional Methods

The comprehensive study, which will be presented at the Alzheimer’s Association International Conference (AAIC) in Philadelphia, compared the effectiveness of leading commercial blood tests against traditional diagnostic methods such as cerebrospinal fluid (CSF) tests and positron emission tomography (PET) scans. The findings, available on the MedRxiv pre-print server, indicate that these blood tests can accurately identify amyloid plaques—a key marker of Alzheimer’s disease—with a level of precision comparable to established techniques.

Julie Gerberding, MD, MPH, President and CEO of the FNIH, highlighted the importance of these findings. She stated, “The recent approvals of new anti-amyloid drugs—and the many treatments being studied in clinical trials—underscore the pressing need for more accessible, less invasive testing for early detection of Alzheimer’s.” Gerberding emphasized that this research provides a valuable dataset for the scientific community, advancing the development of diagnostic tools and therapeutic options for Alzheimer’s.

Evaluating Commercial Blood Tests for Alzheimer’s Diagnosis

The study focused on several commercially available blood tests developed by ALZpath, C2N Diagnostics, Fujirebio Diagnostics, Janssen, Quanterix, and Roche Diagnostics. Utilizing blood samples from the Alzheimer’s Disease Neuroimaging Initiative (ADNI), researchers assessed these tests’ ability to detect amyloid plaques, tau tangles, brain volume reduction, and clinical dementia symptoms. The results confirmed that some blood tests are as reliable as cerebrospinal fluid tests in diagnosing Alzheimer’s.

Suzanne Schindler, MD, PhD, a clinical neurologist and Fluid Biomarker Core Leader at Washington University School of Medicine, noted, “Many Alzheimer’s blood tests are now clinically available. Some are highly accurate, while others are little better than flipping a coin. Doctors need to know which tests can be trusted.” Schindler emphasized that the study’s dataset, freely accessible to researchers, will help answer further questions about the reliability of these tests.

Implications for Alzheimer’s Research and Drug Development

The study also underscored the potential of blood tests in accelerating drug development by improving participant selection for clinical trials. Blood tests measuring levels of the protein p-tau217 were identified as particularly accurate in determining amyloid plaque presence. This advancement could not only enhance diagnostic accuracy but also aid in identifying pre-symptomatic individuals at risk of developing cognitive symptoms.

An ongoing goal of Alzheimer’s research is to evaluate treatments that may prevent or slow cognitive decline in individuals with early Alzheimer’s brain changes. The FNIH study found that some blood tests could accurately detect low levels of brain amyloid in individuals without cognitive impairment, providing further insight into the disease’s progression.

Future Research and Data Availability

The data from this study are available via ADNI, offering opportunities for further research into the performance of these tests and their impact on various scientific questions, including age, sex, genetics, and social determinants of health. This continued research is crucial for refining diagnostic methods and developing effective treatments for Alzheimer’s disease.

  Alzheimer’s Association International Conference, Alzheimer’s Disease Neuroimaging Initiative, ALZpath, C₂N Diagnostics, Foundation for the National Institutes of Health, Fujirebio Diagnostics, Janssen, Julie Gerberding, Quanterix, Roche Diagnostics, Suzanne Schindler