title: Sleep duration and reported functional capacity among black and white US adults.
abstract: OBJECTIVE
  Evidence suggests that individuals reporting sleeping below or above the population's modal sleep duration are at risk for diabetes, hypertension, and other cardiovascular diseases. Evidence also indicates that individuals with these conditions have reduced functional capacity. We assessed whether reported sleep duration and functional capacity are independently associated and whether individuals' race/ethnicity has an effect on this association.
  
  
  METHODS
  Data were obtained from 29,818 black and white Americans (age range: 18-85 years) who participated in the 2005 National Health Interview Survey (NHIS). The NHIS uses a multistage area probability design sampling of non-institutionalized representatives of the US civilian population. Of the sample, 85% were white and 56% were women.
  
  
  RESULTS
  Univariate logistic regression analysis showed that individuals sleeping < 6 h were 3.55 times more likely than those sleeping 6-8 h to be functionally impaired (34% vs 13%; p < 0.001). Likewise, those sleeping > 8 h were 3.77 times more likely to be functionally impaired (36% vs 13%; p < 0.001). Individuals of the black race/ethnicity were more likely to be functionally impaired than their white counterparts (23% vs 19%; p < 0.001). Multivariate-adjusted regression analyses showed significant interactions between individuals' race/ethnicity and short sleep with respect to functional capacity (black: OR = 2.78, p < 0.0001; white: OR = 2.30, p < 0.0001). Significant interactions between race/ethnicity and long sleep were also observed (black: OR = 2.43, p < 0.001; white: OR = 2.63, p < 0.001).
  
  
  CONCLUSIONS
  Our findings suggest that individuals' habitual sleep duration and their race/ethnicity are significant predictors of their functional capacity.
authors.affiliation: Brooklyn Health Disparities Center, Department of Medicine, SUNY Downstate Medical Center, Brooklyn, NY, USA.
authors.forename: Perry
authors.initials: P
authors.lastname: Brimah
authors.forename: Franscene
authors.initials: F
authors.lastname: Oulds
authors.forename: Oladipupo
authors.initials: O
authors.lastname: Olafiranye
authors.forename: Mirnova
authors.initials: M
authors.lastname: Ceide
authors.forename: Shavon
authors.initials: S
authors.lastname: Dillon
authors.forename: Olasumbo
authors.initials: O
authors.lastname: Awoniyi
authors.forename: Joao
authors.initials: J
authors.lastname: Nunes
authors.forename: Girardin
authors.initials: G
authors.lastname: Jean-Louis
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006184:Habits; D006304:Health Status; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011788:Quality of Life; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000208:ethnology*; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data
keywords: Sleep duration; functional capacity; race/ethnicity