Daily Staff Writer

People with Alzheimer’s appear to have unusually high levels of a certain protein in their blood, and a simple blood test might be able to diagnose the disease before its symptoms appear, a preliminary study suggests.

That could give patients and families more time to plan for the future and might open the door to more effective treatment, said researcher Wilfred Jefferies.

In addition, tracking levels of the protein might quickly show how well medications are working, which could speed up development of new drugs and help doctors tailor therapy to patients, he said.

Jefferies emphasized that much more work is necessary to see if such a blood test would be useful.

Further studies in hundreds of people are needed to see if levels of the protein, called p97, are elevated before Alzheimer’s becomes apparent, as well as whether high levels also appear in other neurological diseases or are unique to Alzheimer’s, he said.

In addition, it’s not clear what the protein normally does in the body, why it would be elevated in Alzheimer’s or what role it may play in the disease.

The work was reported in the November issue of the journal Nature Medicine by Jefferies, an associate professor in the Biotechnology Laboratory at the University of British Columbia in Vancouver, Canada; Malcolm Kennard and Dr. Howard Feldman of the university; and Dr. Tatsuo Yamada of Chiba University in Japan.

Zaven Khachaturian, director of the Alzheimer’s Association Ronald and Nancy Reagan Research Institute, called the findings provocative and exciting. He also emphasized that the work needs to be followed up before its usefulness can be known.

Jefferies and colleagues compared blood levels of p97 in 27 Canadians with probable Alzheimer’s vs. 25 without it, as well as eight Japanese people with probable Alzheimer’s vs. seven participants with other neurological diseases. Alzheimer’s patients showed consistently higher p97 levels, well above those of the other participants.

Levels of p97 appeared to be higher in more advanced cases, and a statistical analysis suggested that the protein levels might start to rise two years before symptoms of Alzheimer’s appear.

Experts say brain deterioration in Alzheimer’s begins some 20 to 40 years before symptoms appear and suggest that if treatments could be started during this early period, it might delay symptoms.

A five-year delay would make the number of people affected by Alzheimer’s drop by half, Khachaturian said. That’s because many elderly people with Alzheimer’s die of some unrelated cause before symptoms of the disease appear.