title: Neighbourhood racial/ethnic composition and segregation and trajectories of cognitive decline among US older adults.
abstract: BACKGROUND
  The influence of the sociodemographic context of one's environment on cognitive ageing is not well understood.
  
  
  METHODS
  We examined differences in cognitive trajectories according to the racial/ethnic characteristics of the residential environment. On the basis of 63 996 person-years of data from a nationally representative cohort of 6150 adults over the age of 50 years from the Health and Retirement Study, we used multivariate linear mixed models to determine the effect of neighbourhood racial/ethnic composition and county-level segregation on cognitive function and cognitive decline over a 10-year period.
  
  
  RESULTS
  In models adjusting for individual demographic and health characteristics, Hispanic composition had a significant positive association with cognitive function (standardised β=0.136, p<0.05) and moderate evidence of an association with greater cognitive decline (standardised β=-0.014, p=0.09). Greater Hispanic-white segregation was associated with statistically significant higher cognitive function at baseline (standardised β=0.099, p<0.001) and greater cognitive decline (standardised β=-0.011, p<0.01). For a 20 percentage-point increase in Hispanic composition and segregation, the observed associations implied 1 and 1.25 additional years of cognitive ageing over 10 years, respectively. These effects did not differ by individual race/ethnicity and were not explained by neighbourhood socioeconomic status or neighbourhood selection. Black composition and black-white segregation did not have a significant influence on cognitive ageing.
  
  
  CONCLUSIONS
  This study demonstrates disparities in the progression of cognitive ageing according to racial/ethnic characteristics of the neighbourhood environment.
authors.affiliation: RAND Corporation, Santa Monica, California, USA.
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Kovalchik
authors.affiliation: RAND Corporation, Santa Monica, California, USA.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Slaughter
authors.affiliation: RAND Corporation, Santa Monica, California, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Miles
authors.affiliation: RAND Corporation, Santa Monica, California, USA.
authors.forename: Esther M
authors.initials: EM
authors.lastname: Friedman
authors.affiliation: RAND Corporation, Santa Monica, California, USA.
authors.forename: Regina A
authors.initials: RA
authors.lastname: Shih
mesh_terms: D001741:Black or African American / Q000523:psychology / Q000706:statistics & numerical data; D000368:Aged; D000375:Aging; D019352:Censuses; D003072:Cognition Disorders / Q000191:economics / Q000208:ethnology* / Q000209:etiology; D005260:Female; D015438:Health Behavior; D054624:Health Status Disparities; D006306:Health Surveys; D006630:Hispanic or Latino / Q000523:psychology / Q000706:statistics & numerical data; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D063505:Racism / Q000523:psychology* / Q000706:statistics & numerical data; D012111:Residence Characteristics / Q000145:classification* / Q000706:statistics & numerical data; D012931:Social Environment; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology; D044465:White People / Q000523:psychology / Q000706:statistics & numerical data
keywords: AGEING; COGNITION; ETHNICITY; Neighborhood/place