November 12, 2008

Imaging Agent May Help ID Alzheimer’s

U.S. researchers have developed an imaging agent that may aid in early Alzheimer's disease diagnosis.

Study authors Dr.William Klunk and Chester Mathis, along with colleagues at the University of Pittsburgh, said Pittsburgh Compound B, an imaging agent, could facilitate the early diagnosis of Alzheimer's disease, and has been used to identify amyloid deposition -- proteins believed to destroy brain cells in Alzheimer's patients -- in the brains of clinically older adults.

In the study, led by Dr. Howard Aizenstein, 43 participants with no impairment on cognitive testing ages 65-88 were scanned using the imaging agent known Pittsburgh Compound B or PiB. Twenty-one percent showed early amyloid deposition in at least one area of the brain, which is similar to rates found in postmortem studies.

The finding suggests there may be as many people in this age group with the early brain changes, but no visible symptoms of Alzheimer's disease, as there are people with recognized Alzheimer's disease.

Klunk noted that those with plaques preformed just as well as those without on cognitive tests may show the brain can tolerate these plaques for years before effects are seen.

"We suspect that people with amyloid deposits and normal brain functioning have a high risk of developing Alzheimer's disease in the future," Klunk said in a statement. "But we do not yet have proof of this."

The findings were published in the Archives of Neurology.