Midlife exposure to neighborhood greenness and later-life cognitive decline: The Multi-Ethnic Study of Atherosclerosis

Abstract

Purpose: We investigated whether living in greener neighborhoods in midlife is associated with slower cognitive decline in later life. Methods: We used data on 2,881 participants from the population-based Multi-Ethnic Study of Atherosclerosis. Geocoded residential addresses (1980–2009) were used to derive midlife neighborhood greenness exposure defined as a 10-year mean of annual normalized difference vegetation index values (based on satellite imagery) during the midlife period (ages 45–54). Cognitive testing over ~ 10 years, when the participants were ≥ 55-year-olds, captured global cognition and processing speed. Multivariable linear mixed effects regression estimated associations between the 10-year midlife greenness measure and global cognition and processing speed z-scores in later life and whether greenness-cognition associations varied by age at first cognitive visit. Results: Greater midlife greenness was associated with slower annual decline in processing speed in the overall sample. We found no differences in associations by age at first cognitive visit. Conclusion: In an ethnoracially and geographically diverse US cohort, living in greener neighborhoods in midlife was associated with slower cognitive decline (i.e., processing speed) in later life.