title: Shorter sleep duration is associated with decreased insulin sensitivity in healthy white men.
abstract: OBJECTIVE
  Short sleep has been linked to increased risk for type 2 diabetes and incident cardiovascular disease and acute sleep restriction impairs insulin-mediated glucose disposal. Here, we examined whether indices of glucose metabolism vary with naturally occurring differences in sleep duration.
  
  
  METHODS
  Subjects were midlife, nondiabetic community volunteers (N = 224; mean age 44.5 ± 6.6 y [range: 30-54]; 52% female; 89% white). Laboratory measures of insulin sensitivity (Si) and acute secretion (AIRg), glucose effectiveness (Sg), and disposition index (Di) were obtained from a 180-min, intravenous glucose tolerance test.
  
  
  RESULTS
  Shorter self-reported sleep duration (in hours) was associated with lower Si (P = 0.043), although an interaction of sleep duration with participant race (β = -0.81, P = 0.002) showed this association significant only in whites. Moreover, sex-stratified analyses revealed that shorter sleep duration predicted lower Si in white men (β = 0.29, P = 0.003) but not in white women (P = 0.22). Findings were similar for AIRg. The relationship between sleep duration and AIRg was moderated by race as well as sex, such that shorter sleep duration associated with greater insulin release only in white men (β = -0.28, P = 0.004). Sleep duration was unrelated to Sg and Di (P's > 0.05).
  
  
  CONCLUSIONS
  Our findings suggest that shorter sleep duration may impair insulin sensitivity and beta-cell function in nondiabetic white men, possibly contributing to later type 2 diabetes and cardiovascular disease.
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Wong
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Manuck
authors.affiliation: School of Nursing, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Monica M
authors.initials: MM
authors.lastname: DiNardo
authors.affiliation: Division of Endocrinology and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Mary
authors.initials: M
authors.lastname: Korytkowski
authors.affiliation: Department of Psychology, University of Pittsburgh, Pittsburgh, PA.|Heart and Vascular Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Muldoon
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000209:etiology; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology; D005260:Female; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test; D064368:Healthy Volunteers; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D057566:Self Report; D012727:Sex Characteristics; D012890:Sleep / Q000502:physiology*; D013997:Time Factors; D044465:White People
chemical_list: D007328:Insulin; D005947:Glucose
keywords: glucose metabolism; insulin sensitivity; minimal model; sex differences; sleep duration