Associations between neighborhood environments across the life course and Alzheimer's disease and related dementia outcomes among Hispanic older adults born in and outside the US

PROJECT SUMMARY
Hispanic older adults are 1.5 times more likely to develop Alzheimer’s disease and related dementias (ADRD)
compared to White older adults. Social and built environments (SBE) are social determinants of health linked to
late-life cognitive function and ADRD risk. Detrimental neighborhood SBE are unevenly distributed across
populations and disproportionately affect minoritized groups including US Hispanic populations. Research is
growing on neighborhood SBE and ADRD among Hispanic populations, but few studies have investigated their
life course neighborhood SBE and how SBE-ADRD associations differ depending on place of birth. In this study,
we will use data on Hispanic participants from the Healthy Brain Initiative (HBI), a longitudinal cohort study of
≥50-year-olds without dementia from the racially/ethnically and socioeconomically diverse South Florida region.
This study aims to: (1) characterize life course neighborhood SBE (e.g., access to greenspace, socioeconomic
status) and how they differ between individuals born in and outside the US; (2) determine whether associations
between life course neighborhood SBE exposures and late-life ADRD outcomes vary depending on place of birth
(in or outside US) and percentage of life lived in the US; and (3) conduct semi-structured interviews with ~25
Hispanic older adults to develop a richer understanding of neighborhood environments and associated health
behaviors and exposures experienced throughout the life course and how they differ between those born in and
outside the US. Primary data collection will include administration of a questionnaire on neighborhood SBE from
childhood, young adulthood, midlife and late life and semi-structured interviews of HBI participants. In ArcGIS,
residential addresses will be geocoded and linked to satellite imagery and Area Deprivation Index data to
characterize participants’ neighborhood socioeconomic status and greenspace access. The questionnaire and
GIS data will be merged with cognitive (i.e., Cognivue global cognition score and cognitive domains such as
episodic memory) and magnetic resonance imaging data (i.e., hippocampal and white matter hyperintensity
volume and total brain volume in AD regions of interest). We hypothesize that life course neighborhood SBE
exposures and their associations with ADRD outcomes will vary by place of birth and percentage of life lived in
the US, and through the semi-structured interviews, we will develop possible explanations for any observed
differences that can be tested in subsequent studies. Our study will contribute significantly to the nascent body
of research on the impact of acculturation and neighborhood SBE on ADRD risk among Hispanic populations.
Study findings will be used to inform novel instrument development on important neighborhood SBE for
immigrant and Hispanic populations and key neighborhood SBE features to measure in future grant funded
studies on Hispanic ADRD disparities to ultimately inform community-level interventions for these populations.

Grant Number: 5R21AG089003-02
NIH Institute/Center: NIH
Principal Investigator: Lilah Besser