Overview: A new study reveals that higher levels of inequality – whether economic, environmental or health-related – are associated with faster brain ageing, especially in countries with greater disparities. The research, which involved over 5,000 participants from 15 countries, used advanced brain clocks based on deep learning to measure age differences in the brain.
The study found that socioeconomic inequality, pollution and disease contribute significantly to accelerated brain aging, with the most pronounced effects observed in people with dementia and women in Latin American countries. These findings highlight the need for public health policies that address environmental and social factors to promote global healthier brain aging.
Key facts:
- Countries with greater inequalities show faster brain aging, especially in areas most affected by aging.
- Socioeconomic inequality, pollution and disease are key factors driving accelerated brain aging.
- Women in Latin American countries, especially those with Alzheimer’s, show greater age differences in the brain.
Source: University of Surrey
Countries with greater inequalities – whether economic, pollution or disease-based – showed older brain ages, according to a study published in natural medicine, involving the University of Surrey.
The rate at which the brain ages can vary significantly between individuals, leading to a gap between the estimated biological age of the brain and chronological age (the actual number of years a person has lived).
This difference may be influenced by several things, such as environmental factors such as pollution and social factors such as income or health inequalities, especially in older people and those with dementia. Until now, it was unclear how these combined factors could either accelerate or delay brain aging across different geographic populations.
In the study, a team of international researchers developed ways to measure brain aging using advanced brain clocks based on deep learning of brain networks. This study involved a diverse dataset of 5,306 participants from 15 countries, including Latin American and Caribbean (LAC) nations and non-LAC countries.
By analyzing data from functional magnetic resonance imaging (fMRI) and electroencephalography (EEG), the researchers quantified brain age gaps in healthy individuals and those with neurodegenerative conditions such as mild cognitive impairment (MCI), Alzheimer’s disease and frontotemporal lobe degeneration (FTLD).
Dr. Daniel Abasolo, co-author of the study and head of the Center for Biomedical Engineering at the University of Surrey, said:
“Our research shows that in countries where inequality is higher, people’s brains tend to age faster, especially in areas of the brain most affected by aging. We found that factors such as socioeconomic inequality, air pollution and the impact of disease play a major role in this faster aging process, especially in poorer countries.”
Participants with a diagnosis of dementia, particularly Alzheimer’s disease, showed the most critical age differences in the brain. The research also highlighted gender differences in brain ageing, with women in LAC countries showing greater brain age differences, particularly in those with Alzheimer’s disease.
These differences were linked to biological sex and gender differences in health and social conditions. Variations in signal quality, demographics, or acquisition methods did not explain the results. These findings underscore the importance of environmental and social factors in brain health disparities.
The results of this study have profound implications for neuroscience and brain health, particularly in understanding the interaction between macrofactors (exposome) and the mechanisms underlying brain aging across different populations in healthy aging and dementia.
The study’s approach, which integrates multiple dimensions of diversity in brain health research, offers a new framework for personalized medicine. This framework may be crucial for identifying individuals at risk for neurodegenerative diseases and developing targeted interventions to reduce these risks.
Furthermore, the study’s findings highlight the importance of considering the biological embeddedness of environmental and social factors in public health policies. Policymakers can reduce age differences in the brain and promote healthier aging across populations by addressing issues such as socioeconomic inequality and environmental pollution.
About this brain aging research news
Author: Dalitso Njolinjo
Source: University of Surrey
Contact: Dalitso Njolinjo – University of Surrey
Picture: Image credited to Neuroscience News
Original research: Open access.
“Brain clocks capture diversity and differences in aging and dementia across geographically diverse populations” by Daniel Abasolo et al. Natural medicine
Abstract
Brain clocks capture diversity and disparities in aging and dementia across geographically diverse populations
Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of diversity (including geographic, socioeconomic, sociodemographic, gender, and neurodegeneration) on the brain age gap is unknown.
We analyzed datasets from 5,306 participants across 15 countries (7 Latin American and Caribbean (LAC) countries and 8 non-LAC countries). Based on higher order interactions, we developed a brain age gap deep learning architecture for functional magnetic resonance imaging (2,953) and electroencephalography (2,353).
The data sets included healthy controls and subjects with mild cognitive impairment, Alzheimer’s disease and behavioral variant frontotemporal dementia. LAC models demonstrated older brain ages (functional magnetic resonance imaging: mean directional error = 5.60, root mean square error (rmse) = 11.91; electroencephalography: mean directional error = 5.34, rmse = 9.82) associated with frontoposterior networks compared to not -LAC models.
Structural socio-economic inequality, pollution and health disparities were influential predictors of increased brain age gaps, particularly in LAC (R² = 0.37, F² = 0.59, rmse = 6.9). An increasing brain age gap was found from healthy controls to mild cognitive impairment to Alzheimer’s disease. In the LAC, we observed larger brain age gaps in women in control and Alzheimer’s disease groups compared to the respective men.
The results were not explained by variations in signal quality, demographics, or collection methods. These findings provide a quantitative framework that captures the diversity of accelerated brain aging.