title: Ethnicity, sleep, mood, and illumination in postmenopausal women.
abstract: BACKGROUND
  This study examined how ethnic differences in sleep and depression were related to environmental illumination and circadian rhythms.
  
  
  METHODS
  In an ancillary study to the Women's Health Initiative, 459 postmenopausal women were recorded for one week in their homes, using wrist monitors. Sleep and illumination experience were estimated. Depression was self-rated with a brief adjective check list. Affective diagnoses were made using the SCID interview. Sleep disordered breathing was monitored with home pulse oximetry.
  
  
  RESULTS
  Hispanic and African-American women slept less than European-American women, according to both objective recordings and their own sleep logs. Non-European-American women had more blood oxygen desaturations during sleep, which accounted for 26% of sleep duration variance associated with ethnicity. Hispanic women were much more depressed. Hispanic, African-American and Native-American women experienced less daily illumination. Less daily illumination experience was associated with poorer global functioning, longer but more disturbed sleep, and more depression.
  
  
  CONCLUSIONS
  Curtailed sleep and poor mood were related to ethnicity. Sleep disordered breathing was a factor in the curtailed sleep of minority women. Less illumination was experienced by non-European-American women, but illumination accounted for little of the contrasts between ethnic groups in sleep and mood. Social factors may be involved.
authors.affiliation: Department of Psychiatry, University of California, San Diego, CA, USA. dkripke@ucsd.edu
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Kripke
authors.forename: Girardin
authors.initials: G
authors.lastname: Jean-Louis
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Elliott
authors.forename: Melville R
authors.initials: MR
authors.lastname: Klauber
authors.forename: Katharine M
authors.initials: KM
authors.lastname: Rex
authors.forename: Arja
authors.initials: A
authors.lastname: Tuunainen
authors.forename: Robert D
authors.initials: RD
authors.lastname: Langer
mesh_terms: D001741:Black or African American; D000368:Aged; D002940:Circadian Rhythm / Q000502:physiology*; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000208:ethnology*; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D008029:Lighting; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010092:Oximetry; D017698:Postmenopause / Q000208:ethnology* / Q000502:physiology / Q000523:psychology; D011446:Prospective Studies; D012890:Sleep / Q000502:physiology*; D012891:Sleep Apnea Syndromes / Q000175:diagnosis / Q000208:ethnology; D044465:White People; D016387:Women's Health