title: Socioeconomic Status, Race/Ethnicity, and Diurnal Cortisol Trajectories in Middle-Aged and Older Adults.
abstract: Slow afternoon cortisol decline may be a marker of aging. We hypothesize that lower socioeconomic status (SES) and African American race are associated with lower waking cortisol and slower afternoon decline.
  
  
  
  Six salivary cortisol samples, collected within a 24-hr period from 566 cohort participants aged 56-78 years, were examined in random-effects models. SES measures included socioeconomic vulnerability (household income and assets <500% of poverty) and education (≥college, some college, and ≤high school). African Americans were compared with all others.
  
  
  
  Adjusting for age and sex, intermediate, but not low, education was associated with approximately 17% lower average waking cortisol and 1% slower decline, compared with high education. Socioeconomic vulnerability was not associated with waking cortisol or linear decline. Accounting for African American race/ethnicity, socioeconomic vulnerability was associated with a 3% faster decline, and education was not associated with cortisol. African Americans had 26% lower average waking cortisol and 1% slower decline than others.
  
  
  
  African American race/ethnicity, but not lower SES, was associated with lower waking cortisol and slower afternoon decline in middle-aged and older adults. This pattern is likely a marker of earlier biological aging in vulnerable groups. Race/ethnicity may compete with SES as a measure of cumulative vulnerability.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore Maryland.|Department of Acute and Chronic Care, Johns Hopkins School of Nursing, Baltimore, Maryland.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Samuel
authors.affiliation: Division of Geriatric Medicine and Gerontology, Department of Medicine, Johns Hopkins Center on Aging and Health, Baltimore, Maryland.
authors.forename: David L
authors.initials: DL
authors.lastname: Roth
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore Maryland.|Department of Environmental Health Sciences.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Schwartz
authors.affiliation: Department of Health, Behavior and Society, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland.|Johns Hopkins University Center for Health Disparities Solutions, Baltimore, Maryland.
authors.forename: Roland J
authors.initials: RJ
authors.lastname: Thorpe
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore Maryland.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Glass
mesh_terms: D001741:Black or African American / Q000523:psychology / Q000706:statistics & numerical data; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology / Q000523:psychology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis* / Q000502:physiology; D008297:Male; D008875:Middle Aged; D044469:Racial Groups / Q000523:psychology / Q000706:statistics & numerical data*; D012463:Saliva / Q000737:chemistry; D012923:Social Class; D044465:White People / Q000523:psychology / Q000706:statistics & numerical data
chemical_list: D006854:Hydrocortisone