Protein in spinal fluid appears to predict Alzheimer's

In the absence of a cure for Alzheimer's disease, scientists are focusing a great deal of effort on early detection and diagnosis, so perhaps symptoms can be postponed. German researchers believe they have found a biomarker in spinal fluid that could help physicians identify which patients will develop the degenerative memory disorder. Patients with high levels of soluble amyloid precursor protein beta were more likely to develop the disease, according to researchers at Technical University Munich, writing in the journal Neurology.

People with Alzheimer's usually have lower levels of beta amyloid and higher levels of tau protein in their spinal fluid. Ordinarily, doctors test for these levels to confirm dementia is caused by Alzheimer's, but not for early detection of the disease. Amyloid precursor protein (APP) is a kind of building block of beta amyloid a that is what Munich's Robert Perneczky and colleagues were searching for remnants of.

"If you are cutting out a cookie, it's the dough around the cookie that's left behind," Dr. Marc Gordon, an Alzheimer's researcher at The Feinstein Institute for Medical Research in Manhasset, NY, told Reuters. "That is what they were measuring here."

The study tracked 58 people with slight memory problems, or mild cognitive impairment, over the course of three years. Those who progressed to Alzheimer's had much higher levels of a remnant of APP, soluble amyloid precursor protein beta, in their spinal fluid than those who did not develop the disease. When combined with other biomarkers, such as the presence of tau and a person's age, the test was was about 80 percent accurate, Reuters reports.

"The ability to diagnose Alzheimer's early is a key goal for doctors and researchers," Rebecca Wood, chief executive of Alzheimer's Research UK, told the BBC. "This small study provides a potential new lead to follow up."

- read the Reuters report
- the BBC filed this story
- and read the abstract in the journal Neurology