Brain Tracer Indicates Risk of Future Cognitive Decline
(HealthDay News) – A radioactive tracer that can image amyloid-beta deposits in the brain can indicate whether older adults are at risk of cognitive decline and developing Alzheimer's disease.
P Murali Doraiswamy, MD, from the Duke University Medical Center in Durham, NC, and colleagues performed florbetapir F 18 positron emission tomography (PET), which images amyloid-beta, on 151 older subjects. Of these, 69 were cognitively normal, 51 had been recently diagnosed with mild cognitive impairment, and 31 had been diagnosed with Alzheimer's disease dementia.
Over the course of 36 months the researchers found that normal and mildly impaired patients who had been positive for amyloid-beta at baseline showed clinical worsening on two cognitive tests. Mildly impaired patients who were positive for amyloid-beta also showed worsening on additional cognitive tests, and those with higher cerebral to cerebellar standardized uptake value ratios at baseline also had declining scores on several cognitive tests. Mildly impaired patients were more likely to develop Alzheimer's disease dementia if they were positive for amyloid-beta at baseline.
"Our findings and other reports suggest that amyloid PET tracers may have promise for indicating risk of subsequent cognitive decline in patients with mild cognitive impairment and cognitively normal older adults," Doraiswamy and colleagues conclude.
The study was funded by Eli Lilly/Avid Radiopharmaceuticals; several authors are employed by the company. Many authors disclosed financial ties to the pharmaceutical industry.