New blood test could help diagnose and track Alzheimer’s disease

Researchers have developed a blood test that may help diagnose Alzheimer’s disease and assess its progression in patients with memory and thinking issues, according to a study published in the journal Nature Medicine. The test detects a tau protein fragment, eMTBR-tau243, which correlates with the build-up of tau tangles in the brain—a key marker of Alzheimer’s.A study involving 902 participants found higher levels of this fragment in individuals with mild cognitive impairment and dementia caused by Alzheimer’s, but not in those with other conditions. Experts say this test could improve treatment decisions, especially with new Alzheimer’s drugs like donanemab and lecanemab, which are most effective in early stages.However, scientists caution that the test requires specialized lab equipment and is not yet widely available. Separate research has also identified a protein ratio in brain fluid that may predict cognitive decline. Experts say both findings could lead to better diagnostics and more personalized treatments for Alzheimer’s patients.