On 11 November, a team of researchers led by Prof. Gagan Wig (University of Texas at Dallas) published an article in Nature Aging, showing that brain network changes in adults with fewer years of full-time education may underly the association of lower education with dementia risk.
Demographic studies have identified a close connection between the number of years spent in full-time education (also known as educational attainment) and health disparities, with lower educational attainment associated with increased risk of mental health disorders and dementia in older adults. However, the brain changes underlying this association are not fully understood.
To address this question, Prof. Wig and co-authors analysed a large dataset of brain scans from participants in longitudinal studies of normal aging and dementia at the Charles F. and Joanne Knight Alzheimer Disease Research Center in St. Louis. Participants were regularly scanned for a period of up to 9 years and came from a variety of socioeconomic backgrounds, with different levels of educational attainment. Constructing brain network graphs of structure and function using the scan data, the researchers observed that the way functional brain networks were organised varied depending on factors such as age, cognitive ability and environment.
In some individuals, brain network organisation stayed broadly similar as they aged. However in others, brain network organisation changed or declined as they aged. The researchers observed that older adults (>65 years) with a university education tended to show fewer changes in brain network organisation as they aged, unlike their peers with lower educational attainment. Declining brain network organisation predicted impending changes in dementia severity and was associated with established socioeconomic risk factors for dementia. The prognostic value of brain network changes was independent of biological risk factors such as APOE status and the presence of Alzheimer's disease-associated pathology, such as amyloid or tau accumulation. Together, these results suggest that brain network organisation may be a useful indicator for individual brain health in aging.
