Cross-ethnic cohort study shows that brain resilience is significantly associated with aging, vascular abnormalities and cognitive decline

As we age, various brain abilities such as cognition gradually decline. However, because the brain has a certain degree of resilience, it will slow down the rate of this decline. Current studies have shown that cognitive impairment and cerebrovascular disease in late life are the result of a series of events in the life process, among which vascular risk factors play a vital role. However, traditional indicators in current brain health assessment tools, such as brain morphology and volume, cannot significantly reflect these risk factors. It is particularly important to develop new objective indicators that can reflect risk factors for neurological diseases. Studies have shown that human brain connectomics can quantify and analyze global changes in brain topology based on a network perspective, and brain resilience reflects the brain's ability to withstand external perturbations, and its resilience level also reflects an anti-aging ability. Therefore, the innovative brain resilience index designed based on brain network theory is expected to overcome the above difficulties and become an effective biomarker reflecting the early state of potential brain and nervous system diseases.

Recently, Professor Liu Tao's team from the School of Biological and Medical Engineering of Beihang University and Professor Wang Yongjun's team from Beijing Tiantan Hospital affiliated to Capital Medical University proposed an innovative objective evaluation index reflecting the level of brain resilience - brain topological resilience (BTR). This indicator is calculated based on the brain structure network, using algorithms such as the percolation model to quantify the damage process and achieve quantitative assessment of brain resilience. In two large cross-ethnic community cohorts, the significant association between brain resilience and aging cognitive level and cerebrovascular risk level was verified. The results were recently published in Science Bulletin.

Figure 1 Article abstract

The study calculated brain topological resilience based on two large community cohorts (Figure 1). The white matter fibers of the brain were reconstructed by fiber tracking of the subjects' diffusion magnetic resonance images, and the brain regions were divided using the standard segmentation template Brainnetome to obtain a brain network of 246 nodes. Afterwards, the study combined the K-shell decomposition algorithm and the node centrality characteristics to quantitatively calculate the resilience index of the network. Afterwards, the study analyzed the association between brain resilience and aging, vascular abnormalities, and cognition. Finally, the study constructed a structural equation model to explore the role of brain resilience in the "aging-cognitive decline" model, and compared it with the traditional brain morphology indicator brain volume to verify the specificity of the brain resilience indicator.

Figure 2 Association between brain resilience and aging, cognition, and vascular abnormalities

The study found that brain resilience indicators showed significant associations with aging, vascular risk factors, and atherosclerosis in both population cohorts. Brain topological resilience showed a negative correlation with age, vascular risk factors, and atherosclerosis indicators, but a positive correlation with brain cognitive ability (Figure 2). This suggests that brain resilience may be a basic feature that supports cognitive ability, and brain resilience will be damaged with aging and the accumulation of vascular risks.

In order to further explore the supporting role of brain resilience on brain cognition during aging, this study used structural equation modeling to analyze the mediating effect of brain resilience. The results of the structural equation model showed that compared with traditional brain morphology indicators (brain volume), brain resilience can significantly mediate the effects of aging, vascular risk factors, and atherosclerosis on cognitive decline (Figure 3). This result suggests that the accumulation of vascular risk factors may lead to cognitive decline by affecting brain resilience. This indicator is expected to become an important indicator for assessing brain health in middle-aged and elderly people, and also provides new insights for exploring cognitive protection strategies during aging.

Figure 3 Brain topological resilience mediates the pathways by which aging and blood vessels affect brain cognition

For more details, please read the full article

Exploring the link between brain topological resilience and cognitive performance in the context of aging and vascular risk factors: A cross-ethnicity population-based study. Science Bulletin (2024). DOI: 10.1016/j.scib.2024.04.018