title: Self-reported sitting time and markers of inflammation, insulin resistance, and adiposity.
abstract: BACKGROUND
  Sedentary behavior is emerging as an independent risk factor for chronic disease; however, potential mechanisms underpinning these observations are not well understood.
  
  
  OBJECTIVE
  This study aimed to investigate the association of self-reported weekday sitting time with biomarkers linked to chronic low-grade inflammation, insulin resistance, and adiposity.
  
  
  METHODS
  This study reports data from individuals attending a diabetes screening program, United Kingdom, 2004-2007; analysis was conducted in 2010. Sitting time and physical activity were measured using the International Physical Activity Questionnaire; biochemical outcomes included fasting and 2-hour postchallenge glucose, fasting insulin, C-reactive protein (CRP), leptin, adiponectin, and interleukin-6 (IL-6).
  
  
  RESULTS
  This study included 505 (female=46%; South-Asian ethnicity=19%, aged 59±10 years, BMI=29.5±4.7) individuals with valid sitting data. Increased sitting time was positively associated with fasting insulin, leptin, leptin/adiponectin ratio, CRP, and IL-6 in women, but not men, after adjustment for age, ethnicity, social deprivation, and smoking and medication status; interaction analysis revealed that the gender-specific differences were significant. The associations for women remained significant after additional adjustment for total moderate- to vigorous-intensity physical activity; however all associations were attenuated when further adjusted for BMI. There was no association between sitting time and glycemic status.
  
  
  CONCLUSIONS
  Total self-reported weekday sitting time was associated with biomarkers linked to chronic low-grade inflammation and poor metabolic health in women, but not men, independent of physical activity.
authors.affiliation: Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom. ty20@le.ac.uk
authors.forename: Thomas
authors.initials: T
authors.lastname: Yates
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Khunti
authors.forename: Emma G
authors.initials: EG
authors.lastname: Wilmot
authors.forename: Emer
authors.initials: E
authors.lastname: Brady
authors.forename: David
authors.initials: D
authors.lastname: Webb
authors.forename: Bala
authors.initials: B
authors.lastname: Srinivasan
authors.forename: Joe
authors.initials: J
authors.lastname: Henson
authors.forename: Duncan
authors.initials: D
authors.lastname: Talbot
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Davies
mesh_terms: D050154:Adiposity; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D003430:Cross-Sectional Studies; D003625:Data Collection; D005260:Female; D006801:Humans; D007249:Inflammation / Q000453:epidemiology* / Q000209:etiology; D007333:Insulin Resistance; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009043:Motor Activity; D057185:Sedentary Behavior; D012737:Sex Factors; D013997:Time Factors; D006113:United Kingdom
chemical_list: D015415:Biomarkers