title: Perceived stress and change in cognitive function among adults 65 years and older.
abstract: OBJECTIVE
  Exposure to acute and chronic stress can affect learning and memory, but most evidence comes from animal studies or clinical observations. Almost no population-based studies have investigated the relation of stress to cognition or changes in cognition over time. We examined whether higher levels of perceived stress were associated with accelerated decline in cognitive function in older blacks and whites from a community-based population sample.
  
  
  METHODS
  Participants included 6207 black and white adults (65.7% black, 63.3% women) from the Chicago Health and Aging Project. Two to five in-home assessments were completed over an average of 6.8 years of follow-up and included sociodemographics, health behaviors, psychosocial measures, cognitive function tests, and health history. Perceived stress was measured by a six-item scale, and a composite measure of four tests of cognition was used to determine cognitive function at each assessment.
  
  
  RESULTS
  Mixed-effects regression models showed that increasing levels of perceived stress were related to lower initial cognitive scores (B = -0.0379, standard error = 0.0025, p < .001) and a faster rate of cognitive decline (stress × time interaction: B = -0.0015, standard error = 0.0004, p < .001). Results were similar after adjusting for demographic variables, smoking, systolic blood pressure, body mass index, chronic medical conditions, and psychosocial factors and did not vary by race, sex, age, or education.
  
  
  CONCLUSIONS
  Increasing levels of stress are independently associated with accelerated declines in cognitive function in black and white adults 65 years and older.
authors.affiliation: Rush Alzheimer's Disease Center, 600 South Paulina Ave, Suite 1038, Chicago, IL 60612. neelum_t_aggarwal@rush.edu.
authors.forename: Neelum T
authors.initials: NT
authors.lastname: Aggarwal
authors.forename: Robert S
authors.initials: RS
authors.lastname: Wilson
authors.forename: Todd L
authors.initials: TL
authors.lastname: Beck
authors.forename: Kumar B
authors.initials: KB
authors.lastname: Rajan
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Mendes de Leon
authors.forename: Denis A
authors.initials: DA
authors.lastname: Evans
authors.forename: Susan A
authors.initials: SA
authors.lastname: Everson-Rose
mesh_terms: D000368:Aged; D044383:Black People / Q000706:statistics & numerical data; D002641:Chicago / Q000453:epidemiology; D003072:Cognition Disorders / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D013315:Stress, Psychological / Q000150:complications* / Q000453:epidemiology / Q000523:psychology; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American
keywords: aging; cognitive function; longitudinal; risk factors; stress