Test may help "which came first" question in Alzheimer's

A new test may help scientists answer a perplexing "which came first" question about the development of Alzheimer's disease, possibly pointing the way to earlier diagnosis or even treatment.

Brain deposits of a small protein known as amyloid beta long have been associated with Alzheimer's. But scientists have been unable to determine whether the body begins producing too much of the protein or loses the ability to clear it away.

Now, a research team led by Dr. Randall J. Bateman at Washington University in St. Louis is poised to find that answer with a test that for the first time can monitor the protein.

An initial test of the new technique on six healthy volunteers determined that the protein is quickly produced and quickly cleared, keeping it in balance in the central nervous system, the researchers report in Monday's online issue of the journal Nature Medicine.