New Alzheimer's definition suggested

The new guidelines in US are based on biology

A radical change in the way Alzheimer’s disease is defined, focusing on biological changes in the body rather than clinical symptoms such as memory loss and cognitive decline, has been proposed by researchers, Reuters reports.


The new research framework was released  by the US Alzheimer’s Association and the National Institute on Aging.


It outlines measurable changes in the brain that set Alzheimer’s apart from other causes of dementia


Much of the general public views the terms dementia and Alzheimer’s disease as interchangeable, but they are not,” said Dr. Clifford Jack of the Mayo Clinic in Rochester, Minnesota, who helped craft the guidelines published in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.


The proposed changes follow guidance announced earlier this year by the U.S. Food and Drug Administration and the European Medicines Agency to encourage the testing of new Alzheimer’s medicines based on biomarkers, rather than on clinical symptoms.


Under the proposed research framework, Alzheimer’s would be characterized by three factors:


evidence of two abnormal proteins associated with Alzheimer’s

- beta amyloid and tau - and evidence of neurodegeneration or nerve cell death,


all of which can be seen through brain imaging or tests of cerebral spinal fluid. It also incorporates measures of severity using biomarkers and a grading system for cognitive impairment.  


The moves would allow companies to test drugs in people before symptoms appear, offering a better chance of intervening before the disease has destroyed too many brain cells.