title: The association of mobility disability, weight status and job strain: A cross-sectional study.
abstract: OBJECTIVE
  The study investigated whether people with mobility disability (MD) and/or obesity had higher job strain than people without it, and whether social support at work modifies this association.
  
  
  METHODS
  The study included 35,160 individuals (25-64 years of age) from the Stockholm Public Health Surveys of 2006 and 2010. Data on MD and obesity (BMI ⩾ 30 kg/m(2)calculated from weight (kg) and height (m)) were self-reported. According to the Demand-Control-Support theory job strain, collective strain, and isolated strain were calculated for six groups of people based on the presence of MD and obesity, using the subtraction approach (demand minus control). Differences in job strain mean scores were estimated by multivariate linear regression. Social support at work was analyzed as a potential effect modifier (high/low).
  
  
  RESULTS
  Obese people with MD had the highest job strain (β = 0.92, 95% CI 0.64-1.19), compared to normal weight people without MD (reference group). We found that social support at work significantly (p<0.001) modifies the association between job strain, MD and obesity. Obese people with MD had the highest isolated strain (β = 2.92, 95% CI 2.52-3.31), and the highest collective strain, although of smaller magnitude (β = 0.34, 95% CI 0.05-0.63), compared to the reference group.
  
  
  CONCLUSIONS
  Obese people with MD perceive higher job strain than non-disabled people of normal weight. Strategies aiming to increase the social support at work may be important for this group of people to prevent them from experiencing unhealthy job strain.
authors.affiliation: Child and Adolescent Public Health Epidemiology, Department of Public Health Science, Karolinska Institutet, Sweden mattias.norrback@ki.se.
authors.forename: Mattias
authors.initials: M
authors.lastname: Norrbäck
authors.affiliation: Child and Adolescent Public Health Epidemiology, Department of Public Health Science, Karolinska Institutet, Sweden.
authors.forename: Jeroen
authors.initials: J
authors.lastname: De Munter
authors.affiliation: Child and Adolescent Public Health Epidemiology, Department of Public Health Science, Karolinska Institutet, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Tynelius
authors.affiliation: Department of Health Sciences, Faculty of Medicine, Lund University, Sweden.
authors.forename: Gerd
authors.initials: G
authors.lastname: Ahlström
authors.affiliation: Child and Adolescent Public Health Epidemiology, Department of Public Health Science, Karolinska Institutet, Sweden.
authors.forename: Finn
authors.initials: F
authors.lastname: Rasmussen
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D006233:Persons with Disabilities / Q000523:psychology* / Q000706:statistics & numerical data; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D051346:Mobility Limitation; D009765:Obesity / Q000453:epidemiology*; D012944:Social Support; D013315:Stress, Psychological / Q000523:psychology*; D013548:Sweden / Q000453:epidemiology; D014937:Work / Q000523:psychology*
keywords: Mobility disability; cross-sectional; job strain; obesity; social support at work; workplace