ICYMI: FDA Approves First Blood Test to Diagnose Alzheimer’s

Blood tests like this one are important advancements in the effort to diagnose Alzheimer’s as early as possible.

iStock/alvarez

The Food and Drug Administration has approved a first-of-its-kind blood test to help diagnose Alzheimer’s disease. The test measures indicators of toxic plaque and tangle buildups in the brain associated with the disease, evaluating blood plasma for two proteins — pTau217 and β-amyloid 1-42. It was approved for use in people aged 55 or older who are experiencing memory loss or other potential indicators of Alzheimer’s.

This test isn’t intended to act as a stand-alone diagnostic tool. Instead, it’s meant to be used alongside other medical evaluations. But the current standard approaches to diagnosing Alzheimer's have practical limitations. PET scans, for example, are a highly effective tool, but they’re expensive and in some cases difficult for patients to access. A separate test analyzes cerebrospinal fluid (CSF) samples, but those must be collected through an invasive spinal tap. Experts hope this blood test, which is comparatively much cheaper and less invasive, and others which could possibly hit the market in coming years, will broaden patient access to more accurate testing.

Big Picture: In the United States, an estimated 1 in 9 people over the age of 65 have Alzheimer’s, and the number of dementia cases nationally is expected to double by 2050 as the population continues to age, according to the Alzheimer’s Association. Blood tests like this one are important advancements in the effort to diagnose Alzheimer’s as early as possible. By the time many patients begin experiencing noticeable symptoms, plaques have already begun accumulating in their brains. The earlier patients can get access to one of the two medications available to reduce amyloid buildup, the more effective those treatments can be at slowing disease progression.

Read More: FDA greenlights first blood test to help diagnose Alzheimer’s disease in the US. CNN

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About the Author

Bella Isaacs-Thomas

Bella is the Staff Writer and Editor for BrainFacts. She previously worked as a digital science reporter at PBS NewsHour, where she was named a fellow in the 2022-2023 class of the National Science-Health-Environment Reporting Fellowships (SHERF) and earned a 2021 D.C. Science Writers Association Newsbrief Award for writing. She graduated from the University of Michigan with a bachelor's degree in 2018.