Neighborhood disadvantage and cognitive function in older adults: The moderating role of young adult general cognitive ability

Neighborhood disadvantage in later life is associated with poorer cognition and increased vulnerability to dementia. Cognitive reserve (CR), an individual's total cognitive resources, may foster cognitive resilience against dementia in the face of neighborhood disadvantage. However, whether the neighborhood disadvantage-cognition association varies across older adults remains understudied and its moderators remain underexplored. We examined associations between late midlife neighborhood disadvantage and five domain-specific cognitive functions as well as the moderating role of young adult CR on these associations. In 1149 community-dwelling men age 61-73 living across the United States, we assessed neighborhood-level socioeconomic disadvantage using the area deprivation index and cognitive performance in executive function, episodic memory, processing speed, verbal fluency, and visual-spatial ability. General cognitive ability assessed at average age 20 was used as a measure of young adult CR. Years of education was included as another potential moderator for comparison. Greater late midlife neighborhood disadvantage was associated with poorer executive function (β = -.09, p < .05) and processing speed (β = -.12, p < .05). Moreover, those with higher young adult CR showed a weaker association between neighborhood disadvantage and executive function (β = .07, p < .02). The same moderation effect was not observed for years of education. Findings are consistent with the idea that neighborhood disadvantage negatively associates with executive function, albeit less so among those with higher young adult CR. Fostering cognitive development to enhance CR earlier in life may buffer against environmental threats to later-life executive function, which is among the earliest cognitive functions affected in aging, and may, in turn, decrease vulnerability to dementia.