Living in a 20-min neighborhood and brain health and resilience in older adults: The Healthy Brain Initiative.

The 20-min neighborhood (20 MN) concept, aimed at fostering livable communities, has garnered increasing attention among urban planners and policy makers. 20 MNs provide most daily needs (e.g., grocery, parks) within a 20-min walk of home. Among 352 older adults in the Healthy Brain Initiative (HBI), we examined whether 20 MN measures were associated with resilience against future cognitive impairment/dementia measured via the Resilience Index (RI), as well as with structural magnetic resonance imaging measures (i.e., hippocampal volume, white matter hyperintensity (WMH) volume). We calculated density of destinations within a 20-min walk of home across seven domains (i.e., social destinations, dining places, shopping/retail, grocery/supermarkets, healthcare facilities, parks, and transit availability) and created a dichotomous 20 MN variable (≥1 destination within a 20-min walk in all seven domains, yes versus no). In multivariable linear regression analyses, greater density of parks, greater density of grocery/supermarkets, and living in a 20 MN were associated lower WMH volumes. Our study suggests brain health benefits for older adults with greater densities of grocery and park destinations within a 20-min walk of home, as well as those living in 20 MNs. Future studies corroborating our findings for beneficial associations between 20 MNs and brain health would provide significant policy implications for dementia prevention.