Life course neighborhood social determinants of health and longitudinal changes in cognition in three Alzheimer’s Disease Research Center cohorts

Abstract

AbstractBackgroundSeminal studies on exposure to life course social determinants of health, such as neighborhood racial segregation and neighborhood poverty, suggest detrimental associations with poorer cognitive function. We aimed to test the opposite by examining the relationship between self‐reported exposure to health‐promoting neighborhood environments over the life course and cognitive function among older adults.MethodParticipants were persons living without dementia at three US Alzheimer’s Disease Research Centers (University of California, Davis in Sacramento (UCD); Washington University in Saint Louis (WU); and Wake Forest University in Winston‐Salem (WFU)). An ancillary study (K01AG063895, PI: Besser) included the Life Course Sociodemographics and Neighborhood Questionnaire (LSNEQ) comprised of indices like neighborhood measures of socioeconomic status (NSES), walking and biking frequency, and greenness from childhood, midlife, and late life. LSNEQ data were linked with late‐life cognitive test z‐scores (Animals and Vegetables Category Fluency, Trail Making Parts A and B) from the National Alzheimer’s Coordinating Center Uniform Data Set. Multivariable linear mixed effects models tested associations between the LSNEQ index scores (composite values over childhood and mid‐ and late‐life) and baseline and longitudinal change in cognitive function controlling for demographics, Center, and baseline global Clinical Dementia Rating (0 or 0.5).ResultThe sample (n = 322) included 65% women, 17% Black, 76% White, and 7% other/mixed racialized group participants and was, on average, 70±7 years old and followed for 2.5±3.2 years. Life Course NSES was lower for UCD (mean = 12.7, SD = 3.5) versus WU (mean = 13.9, SD = 3.2) and WFU (mean = 14.3, SD = 3.2). Life Course Neighborhood Walking and Biking frequency did not differ by Center. Life Course Neighborhood Greenness differed across Centers, and was lowest for WU (mean = 4.8, SD = 1.3) and highest for WFU (mean = 5.6; SD = 1.2). In multivariable analyses, greater Life Course Neighborhood Walking and Biking was associated with higher baseline Trail A scores (estimate = 0.83, 95% CI = 0.08‐1.58) and slower decline on Animals over time (estimate = 0.024, 95% CI = 0.002‐0.045). Greater Life Course Neighborhood Greenness was associated with slower decline on Vegetables over time (estimate = 0.035, 95% CI = 0.001‐0.069).ConclusionThese preliminary findings suggest self‐reported, life course neighborhood exposures and behaviors (i.e., greenness and neighborhood walking/biking) may be associated with better cognition and slower decline in later life.