New Alzheimerās blood test detects 90% of early dementia cases
Scientists are making significant advances in diagnosing Alzheimerās disease through a simple blood test, showing greater accuracy than traditional methods.

In short
- Blood test diagnoses Alzheimerās with nearly 90% accuracy
- Findings highlight the potential of routine blood testing in primary care screening
- Experts stress need for further validation in diverse populations
Scientists are making significant progress toward diagnosing Alzheimerās disease with a simple blood test. Alzheimerās disease is a progressive brain disorder that causes memory loss, cognitive decline, and behavioral changes, primarily affecting older people and impairing daily functioning and quality of life.
A recent study showed that this blood test is more accurate in identifying the condition than traditional methods, such as cognitive testing and CT scans.
The study, published in the journal JAMA, showed that blood tests correctly diagnose Alzheimerās in about 90% of cases among patients with memory problems.
By comparison, dementia specialists using standard methods without expensive PET (positron emission tomography) scans or invasive spinal taps had an accuracy rate of 73%, while primary care doctors had an accuracy rate of 61%.
The findings were presented at the Alzheimerās Association International Conference in Philadelphia and are a major step toward developing accessible and affordable diagnostic tools for Alzheimerās, which affects more than 32 million people worldwide.
Medical experts believe that based on these findings, routine blood testing for cognitive impairment could be included as part of routine primary care checkups, similar to how cholesterol testing is done today.
In recent years, several blood tests for Alzheimerās have been developed. These tests are used primarily to screen participants in clinical trials and to help specialists determine whether a patientās dementia is caused by Alzheimerās or another condition.

The recent study was conducted in Sweden, and experts caution that its results need to be verified in a diverse American population before widespread use in the United States.
Experts also emphasize that the blood test should be part of a comprehensive screening process, used specifically for individuals with memory loss and other symptoms of cognitive decline, not just for those who are currently healthy, in order to predict the development of Alzheimerās in the future.
If scientists find drugs that can delay or prevent Alzheimerās in people who havenāt yet shown cognitive symptoms, testing guidelines could change.
Medical professionals recommend that blood tests be used along with memory and cognitive assessments and CT scans to rule out other possible causes such as stroke or brain tumors. Blood test results should be confirmed with gold-standard methods such as a PET scan or spinal tap to measure amyloid protein, which forms plaques in the brains of Alzheimerās patients.
This advancement raises hope for more effective and accessible diagnosis of Alzheimerās disease, potentially changing the way the disease is detected and managed in the future.