title: Low diurnal variability of apolipoprotein A1, apolipoprotein B and apolipoprotein B/apolipoprotein A1 ratio during normal sleep and after an acute shift of sleep.
abstract: OBJECTIVE
  The aim of this study was to study the diurnal variation of the cardiovascular risk markers apolipoprotein A1 and B and apo B/apo A1 ratio.
  
  
  METHODS
  We have studied the diurnal variation of apolipoprotein A1, apolipoprotein B and apo B/apo A1 ratio during night sleep and the day sleep conditions in seven healthy volunteers (age 22-32 yr). Samples were collected every hour to evaluate the effect of different sampling times on the test results.
  
  
  RESULTS
  The lowest diurnal coefficient of variation (CV) was observed for the apo B/apo A1 ratio, which usually was below 2% but also apolipoprotein A1, apolipoprotein B showed low CV. There were no significant differences between nightsleep and daysleep for any of the studied markers.
  
  
  CONCLUSIONS
  Even if there was a diurnal variation for these markers, the variation was very low. Thus, sampling does not have to be restricted to certain times of the day.
authors.affiliation: Section of Clinical Chemistry, Department of Medical Sciences, Uppsala University, 751 85 Uppsala, Sweden. anders.larsson@akademiska.se
authors.forename: Anders
authors.initials: A
authors.lastname: Larsson
authors.forename: Lena
authors.initials: L
authors.lastname: Carlsson
authors.forename: John
authors.initials: J
authors.lastname: Axelsson
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016632:Apolipoprotein A-I / Q000097:blood*; D001055:Apolipoproteins B / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology; D002940:Circadian Rhythm; D004435:Eating / Q000502:physiology; D006185:Habituation, Psychophysiologic; D006801:Humans; D017286:Polysomnography; D012016:Reference Values; D012890:Sleep / Q000502:physiology*; D014940:Work Schedule Tolerance
chemical_list: D016632:Apolipoprotein A-I; D001055:Apolipoproteins B; D015415:Biomarkers