Cognitive Decline Disparities in Diverse Aging Populations

Cognitive decline in later life is influenced by a complex interplay of genetic, vascular, lifestyle and social determinants, with marked variations observed across racial, ethnic and socioeconomic groups. Minority populations frequently exhibit earlier onset of memory impairment, faster progression to dementia and greater comorbidity with cerebrovascular disease compared with majority groups. Disparities arise from uneven distribution of risk factors such as hypertension, diabetes and social deprivation, as well as from differences in access to diagnostic and therapeutic resources. Under-representation of diverse cohorts in neuroimaging and biomarker studies further limits the generalisability of findings and may lead to mis-calibrated thresholds for clinical diagnosis. Addressing these gaps requires inclusive recruitment, culturally sensitive assessment tools and interventions tailored to the unique profiles of marginalised subgroups. Multifaceted strategies that encompass public health policies, community engagement and precision medicine are essential to mitigate inequities and ensure equitable outcomes as populations age globally.

Research from Nature Portfolio

A recent systematic analysis quantified the racial and ethnic composition of Alzheimer’s neuroimaging studies in the United States, revealing a predominance of non-Hispanic white participants and persistent under-representation of Black, Hispanic and Indigenous groups. Although diversity has improved modestly in the past five years, minoritised populations remain below census-level proportions. The review highlights how skewed samples constrain the applicability of biomarker cut-offs and impede understanding of disease mechanisms in under-studied communities. Enhanced reporting of participant demographics and concerted efforts to broaden recruitment are identified as priorities to redress these imbalances and strengthen the evidence base for all ageing populations.

Cognitive Decline Disparities in Diverse Aging Populations publication trend

The graph below shows the total number of articles in cognitive decline disparities in diverse aging populations across all publications each year (not limited to Nature Index journals).

Technical terms

Biomarker: A measurable indicator of a biological state or condition, such as a protein in cerebrospinal fluid signalling neurodegeneration.

Socioeconomic status: An individual’s or group’s social and economic standing, often measured by income, education and occupation, influencing health outcomes.

APOE ε4 genotype: A variant of the apolipoprotein E gene associated with increased risk of Alzheimer’s disease and greater amyloid deposition in the brain.

White matter hyperintensities: Lesions visible on magnetic resonance imaging that reflect small-vessel vascular damage and predict cognitive impairment.

References

1. Quantification of race/ethnicity representation in Alzheimer’s disease neuroimaging research in the USA: a systematic review. Communications Medicine (2023).
2. Pathways explaining racial/ethnic and socio-economic disparities in incident all-cause dementia among older US adults across income groups. Translational Psychiatry (2022).
3. Effects of Medicare comprehensive medication review on racial/ethnic disparities in nonadherence to statin medications among patients with Alzheimer’s Disease: an observational analysis. BMC Health Services Research (2022).
4. APOEε4 Genotype Is Related to Brain Amyloid Among Mexican Americans in the HABS-HD Study. Frontiers in Neurology (2022).