New blood test to detect early symptoms of Alzheimer disease,says new Study

New Delhi : There is good news for people who are at risk of Alzheimer disease. German scientists have developed a new blood test that can detect Alzheimer's long before the symptoms appear in prospective patients.

Alzheimer is a kind of disease which causes problems with memory, thinking and behaviour. The symptoms usually develop slowly and get worse over time, at times become severe to interfere in daily lives.

The team of experts, led by Klaus Gerwert, professor at Ruhr University Bochum in Germany, observed that one of the hallmarks of Alzheimer's disease is the accumulation of amyloid-beta plaques in the patient's brain. 

The pathological structure of amyloid-beta is rich in a sticky, sheet-like folding pattern that makes it prone to accumulation, while the healthy structure is not.

The two structures absorb infrared light at a different frequency which allows the blood test to determine the ratio of healthy to pathological amyloid-beta in the sample. 

The pathological form is a misfolded version of this molecule and known to start the formation of toxic amyloid-beta molecules that starts accumulating in the brain 15 to 20 years before disease starts. 

Researchers found that the test is reliable to detect amyloid-beta alterations in the blood of participants with mild cognitive impairment which also showed abnormal amyloid deposits in brain scans.

In order to detect blood changes in the onset of disease, the researchers compared blood samples of 65 participants that were later in the follow-up studies diagnosed with Alzheimer's disease with 809 controls. 

The assay was able to detect signs of the disease on average eight years before diagnosis in individuals without clinical symptoms with an overall diagnostic accuracy of 86%. 

The new blood test would possibly offer an opportunity to identify those at risk and may thereby open the door to new avenues in drug discovery, the researchers said.