title: Disparities in sleep characteristics by race/ethnicity in a population-based sample: Chicago Area Sleep Study.
abstract: BACKGROUND
  Prior studies report less favorable sleep characteristics among non-Whites as compared with non-Hispanic Whites. However, few population-based studies have used objective measures of sleep duration, especially in more than two racial/ethnic groups. We tested whether objectively estimated sleep duration and self-reported sleep quality varied by race and whether differences were at least partially explained by the variability in clinical, psychological, and behavioral covariates.
  
  
  METHODS
  Adults aged 35-64 years who self-identified as White, Black, Asian, or Hispanic were randomly sampled from Chicago, IL, and the surrounding suburbs. Our analytic sample included adults who had an apnea-hypopnea index <15 after one night of screening and who completed seven nights of wrist actigraphy for determination of sleep duration, sleep percentage, minutes of wake after sleep onset, and sleep fragmentation (n = 495). Daytime sleepiness was estimated using the Epworth Sleepiness Scale (ESS), and sleep quality was estimated from the Pittsburgh Sleep Quality Index (PSQI).
  
  
  RESULTS
  Following statistical adjustment for age, gender, education, work schedule (ie, day vs. night shift), smoking status, depressive symptoms, body mass index (BMI), hypertension, and diabetes, sleep duration (minutes) was significantly (all p < 0.01) shorter in Black (mean = 399.5), Hispanic (mean = 411.7), and Asian (mean = 409.6) participants than in White participants (mean = 447.4). All remaining sleep characteristics were significantly less favorable among Black participants as compared with White participants. Asian participants also reported significantly more daytime sleepiness than did White participants.
  
  
  CONCLUSIONS
  Differences in sleep characteristics by race/ethnicity are apparent in a sample of adults with a low probability of sleep apnea and following adjustment for known confounders.
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA. Electronic address: carnethon@northwestern.edu.
authors.forename: Mercedes R
authors.initials: MR
authors.lastname: Carnethon
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Peter John
authors.initials: PJ
authors.lastname: De Chavez
authors.affiliation: Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Phyllis C
authors.initials: PC
authors.lastname: Zee
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Kwang-Youn A
authors.initials: KY
authors.lastname: Kim
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.affiliation: Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Goldberger
authors.affiliation: Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Ng
authors.affiliation: Department of Medicine, University of Chicago, Chicago, IL, USA.
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Knutson
mesh_terms: D056044:Actigraphy; D000328:Adult; D002641:Chicago; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D005006:Ethnicity; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D008297:Male; D008875:Middle Aged; D044469:Racial Groups; D057566:Self Report; D012890:Sleep; D011795:Surveys and Questionnaires
keywords: Disparities; Epidemiologic studies; Sleep duration