Brain injuries may remain unhealed long enough to increase Alzheimer’s risk
Preliminary research at Imperial College London has shown that increased levels in binding of the Alzheimer’s-associated radioligand 11C-PiB—the go-to radioactive biochemical substance in PET imaging for cerebral amyloid beta plaque—also show up in people who have had traumatic brain injury, and for more than a decade after the TBI event.
The binding distribution is distinct from that seen in Alzheimer’s brains, but it also overlaps with Alzheimer’s patterns, suggesting a link between brain injury and subsequently occurring dementia, according to the authors of the research report, which was published online Feb. 3 in Neurology.
Lead author Gregory Scott, MBBS, MSc, and colleagues describe how they used 11C-PiB-PET, along with structural and diffusion MRI, to assess and compare images and neuropsychological exams of 10 Alzheimer’s patients, nine TBI patients and nine control participants.
They deployed an automated reference-region extraction process to compute binding-potential (BPND) images of 11C-PiB. This process indicated the density of amyloid beta plaque.
The team found increased 11C-PiB BPND in TBI patients vs. control counterparts. The effect occurred in the posterior cingulate cortex as well as the cerebellum.
Additionally, compared to Alzheimer’s disease, binding after TBI was lower in neocortical regions—but increased in the cerebellum.
This latter effect “suggests a different mechanism for amyloid plaque genesis,” the authors write in their discussion.
“We provide 11C-PiB-PET evidence for the presence of amyloid pathology many years after injury in patients with TBI [and] without dementia,” they conclude. “Our findings support the hypothesis that amyloid plaque pathology is related to the presence of axonal damage produced subsequent to the TBI.”
Scott put the work in consumer-friendly terms for Imperial College London News. The preliminary study, he says, supports the view that “the window of treatment for brain injury is potentially months or even years after the initial event.”
“The work also highlights how damaging brain injury can be,” adds Scott, “and fuels the public health debate about what we can do to protect ourselves against head injuries.”
Dave P. has worked in journalism, marketing and public relations for more than 30 years, frequently concentrating on hospitals, healthcare technology and Catholic communications. He has also specialized in fundraising communications, ghostwriting for CEOs of local, national and global charities, nonprofits and foundations.