Nuke med helps diagnose early Alzheimer’s from amyloid network topology

Using PET with the radiotracer 18F-florbetapir, researchers in Sweden have found that the topology of amyloid clusters can help tip off clinicians to the presence and progression of Alzheimer’s disease in patients who don’t yet present symptoms.

Joana Pereira, PhD, of the Karolinska Institute in Stockholm and colleagues assessed amyloid network topology in asymptomatic individuals with elevated amyloid-beta levels in their cerebrospinal fluid but normal findings on florbetapir PET imaging.

They compared these with results from patients who had more advanced amyloid-beta accumulation, expressed as both abnormally high amyloid-beta levels in cerebrospinal fluid and abnormal findings on florbetapir PET.

“Our findings showed an association between the very early accumulation of amyloid-beta fibrils with an increased covariance and shorter paths between several brain areas that overlapped with the default-mode network,” the authors write in an article published online Nov. 9 in Cerebral Cortex.

Pereira and colleagues further found that asymptomatic individuals with more advanced amyloid pathology showed changes both within and outside the default-mode network compared to early amyloid accumulators.

“Altogether, these findings suggest that the pattern of network changes is different in the earliest and later stages of amyloid-beta pathology,” they write, “and could potentially be used to assess disease progression in the predementia stages of Alzheimer’s disease.”

Journal publisher Oxford Academic has posted the study in full for free.