Currently, the only way to diagnose the disease is to remove brain tissue or to perform an autopsy.
The new study, to be published today in the New England Journal of Medicine, is by doctors at the University of California, Los Angeles, and is part of a larger quest to find a better method to diagnose the condition using tracers that can be detected with a positron emission tomography, or PET, scan.
The new chemical, called FDDNP, attaches to abnormal clumps of proteins called amyloid plaques and nerve cell tangles that develop in Alzheimer’s sufferers and inhibit messages being processed by the brain.
In the study, Dr. Gary Small and his colleagues discovered that the chemical allowed doctors to pick out which of 83 volunteers had Alzheimer’s, which had mild memory problems and which were functioning normally for their age.
It was 98 percent accurate in determining the difference between Alzheimer’s and mild cognitive impairment, which surpassed the 87 percent success rate for a PET scan test that measured sugar metabolism in the brain, and the 62 percent accuracy rate when doctors used a magnetic resonance imaging.
The FDDNP signal can be seen in people years before they develop Alzheimer’s disease, Dr. Small said.
Finding an easier way to track brain deterioration would also make it easier to assess experimental treatments, as researchers try to prevent or reduce the accumulation of plaques and tangles.
Dr. Small and 4 of the other 15 authors named in the research paper have a financial interest in FDDNP, which has been licensed to the German conglomerate Siemens AG. He said he hoped to see it on the market in three years.
About 4.5 million people in the United States have Alzheimer’s, a number that is expected to grow as the population ages. About 15 million to 20 million more have the mild cognitive impairment that often leads to the disease.
Source:The New York Times