LOS ANGELES (CNS) - Brain changes in people with Alzheimer's disease and in those with mild traumatic brain injuries have significant similarities, suggesting new ways to identify patients at high risk for the progressive disease that destroys memory and other important mental functions, according to a USC study released today.
Traumatic brain injuries -- TBIs -- which affect over 1.7 million Americans every year, are often followed by changes in brain structure and function and by cognitive problems such as memory deficits, impaired social function and difficulty with decision-making. Although mild TBI -- also known as concussion -- is a known risk factor for Alzheimer's disease, prior studies haven't quantified the extent to which these conditions share patterns of neural degeneration in the brain.
USC researchers hypothesized that comparing these patterns could reveal not only how the degenerative trajectories of the two conditions are similar but also which features of brain atrophy could predict Alzheimer's risk after TBI.
The study included 33 study participants with TBIs due to a fall, another 66 participants who had been diagnosed with Alzheimer's disease and 81 healthy control participants without either TBI or Alzheimer's. The researchers analyzed MRIs of the patients' brains and created additional computer-generated models to compare dozens of different brain structures, ultimately mapping similarities and differences between the three different groups, according to findings detailed in the journal GeroScience.
In multiple brain areas of both TBI and Alzheimer's participants, the researchers found reduced cortical thickness when compared to the healthy controls. Cortical thickness is roughly correlated with brain age and its thinning is often associated with reductions in attention, memory and verbal fluency, as well as with decreased ability to make decisions, integrate new information and adapt one's behavior to new situations, among other deficits.
“These findings are the first to suggest that cognitive impairment following a traumatic brain injury is useful for predicting the magnitude of Alzheimer's-like brain degradation,'' said study author Andrei Irimia, an assistant professor of gerontology, neuroscience and biomedical engineering at the USC Leonard Davis School of Gerontology and the USC Viterbi School of Engineering. “The results may help health professionals to identify TBI victims who are at greater risk for Alzheimer's disease.''
Photo: Getty Images
Copyright 2021, City News Service, Inc.