title: Sedentary work--associations between five-year changes in occupational sitting time and body mass index.
abstract: OBJECTIVE
  The aim of this study is to investigate the association between five-year changes in occupational sitting and body mass index (BMI) in working adults.
  
  
  METHODS
  We analyzed data from The Danish Work Environment Cohort Study (2005 and 2010, n=3.482). Data on occupational sitting, weight, height and several potential confounders were self-reported. The association between change in occupational sitting (hours) (categorized as large decrease <-7.5, moderate decrease -7.5 to <-2.5, no change -2.5 to 2.5, moderate increase >2.5 to 7.5 and large increase >7.5) and change in BMI was explored by multiple linear regression analyses.
  
  
  RESULTS
  43.0% men and 36.1% women had high occupational sitting time (≥25h per week) at baseline. 31.8% men and 27.2% women decreased while 30.0% men and 33.0% women increased occupational sitting. The proportion of obese (BMI≥30) increased almost 3% for both genders. BMI changed 0.13 (CI: 0.06; 0.20, p=0.0003), per category of change in occupational sitting in women, but no association was found in men.
  
  
  CONCLUSIONS
  In women, there is a positive association between five-year changes in occupational sitting and BMI.
authors.affiliation: National Research Centre for the Working Environment, Copenhagen, Denmark. Electronic address: dorte.eriksen@yahoo.com.
authors.forename: Dorte
authors.initials: D
authors.lastname: Eriksen
authors.affiliation: Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Susanne
authors.initials: S
authors.lastname: Rosthøj
authors.affiliation: Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA), Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Burr
authors.affiliation: National Research Centre for the Working Environment, Copenhagen, Denmark.
authors.forename: Andreas
authors.initials: A
authors.lastname: Holtermann
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009765:Obesity / Q000453:epidemiology / Q000209:etiology; D009790:Occupations / Q000706:statistics & numerical data; D057185:Sedentary Behavior; D012737:Sex Factors; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Body mass index; Change in occupational sitting time; Occupational sitting; Public health; Sedentary behavior; Work