How Societal Inequality Affects Brain Health and Aging

New research from Trinity College Dublin, in collaboration with international partners, reveals a strong connection between societal inequality and reduced brain health in aging populations, with significant implications for dementia risk. Published in Nature Aging, the study explores how socioeconomic disparities, measured by the GINI index, impact brain structure and connectivity across populations in Latin America and the United States. Join Innovative Approaches in Psychiatric Care for more updates on mental health.

The findings demonstrate that higher levels of inequality correlate with reduced brain volume and disrupted neural connectivity, particularly in regions associated with memory and cognitive function, such as the temporo-posterior and cerebellar regions. These effects are more pronounced in Latin American populations, highlighting their vulnerability to socioeconomic stressors.

For individuals with Alzheimer’s disease, the impacts of structural inequality on brain health were especially severe. In contrast, milder effects were observed in frontotemporal lobar degeneration, suggesting a stronger genetic influence in this condition compared to environmental factors.

Interestingly, these associations remained significant even after accounting for age, education, sex, and cognitive ability, underscoring the independent impact of societal inequality on brain health. This finding suggests that living in an unequal society affects brain health regardless of one’s personal socioeconomic status.

Lead researcher Dr. Agustina Legaz, from the ReDLat consortium, emphasized the importance of considering macro-level factors, such as societal and environmental variables, in brain health research. She stated, “Our findings highlight the need to address structural inequality as a biological determinant of brain aging and dementia.”

Corresponding author Dr. Agustín Ibáñez, professor of global brain health at Trinity College, stressed that the rising rates of dementia in low- and middle-income countries necessitate targeted interventions addressing regional disparities.

The study suggests a multi-level approach to improving brain health equity, calling for the examination of other macro-level factors, including air pollution, migration patterns, governance quality, and access to green spaces. By identifying and mitigating these variables, it may be possible to slow down accelerated brain aging and reduce the global dementia burden in disadvantaged communities.

This research emphasizes the far-reaching consequences of societal inequality and advocates for addressing root causes through policy changes, healthcare reforms, and social initiatives.

More Information: Agustina Legaz et al, Structural inequality linked to brain volume and network dynamics in aging and dementia across the Americas, Nature Aging (2024). DOI: 10.1038/s43587-024-00781-2