title: Sedentary time, breaks in sedentary time and metabolic variables in people with newly diagnosed type 2 diabetes.
abstract: OBJECTIVE
  We investigated whether objectively measured sedentary time and interruptions in sedentary time are associated with metabolic factors in people with type 2 diabetes.
  
  
  METHODS
  We studied 528 adults (30-80 years) with newly diagnosed type 2 diabetes, who were participants in a diet and physical activity intervention. Waist circumference (WC), fasting HDL-cholesterol, insulin and glucose levels, HOMA of insulin resistance (HOMA-IR) and physical activity (accelerometer) were measured at baseline and at 6 months follow-up. Linear regression models were used to investigate cross-sectional and longitudinal associations of accelerometer-derived sedentary time and breaks in sedentary time (BST) with metabolic variables.
  
  
  RESULTS
  In cross-sectional analyses each hour of sedentary time was associated with larger WC (unstandardised regression coefficient [B] [95% CI] 1.89 cm [0.94, 2.83]; p < 0.001), higher insulin (B = 8.22 pmol/l [2.80, 13.65]; p = 0.003) and HOMA-IR (B = 0.42 [0.14, 0.70]; p = 0.004), and lower HDL-cholesterol (B = -0.04 mmol/l [-0.06, -0.01]; p = 0.005). Adjustment for WC attenuated all associations. Each BST was associated with lower WC (B = -0.15 cm [- 0.24, -0.05]; p = 0.003) and there was evidence of a weak linear association with HDL-cholesterol, but no association with insulin levels or HOMA-IR. Volume of sedentary time at baseline predicted HDL-cholesterol (B = -0.05 mmol/l [-0.08, -0.01]; p = 0.007), insulin levels (B = 8.14 pmol/l [0.1.51, 14.78]; p = 0.016) and HOMA-IR (B = 0.49 [0.08, 0.90]; p = 0.020) at 6 months, though not WC. Baseline BST did not substantially predict any metabolic variables at follow-up. No change was seen in sedentary time or BST between baseline and 6 months follow-up.
  
  
  CONCLUSIONS
  Higher sedentary time is associated with a poorer metabolic profile in people with type 2 diabetes.
authors.affiliation: Centre for Exercise, Nutrition and Health Sciences, School for Policy Studies, University of Bristol, 8 Priory Road, Bristol BS8 1TZ, UK. ashley.cooper@bris.ac.uk
authors.forename: A R
authors.initials: AR
authors.lastname: Cooper
authors.forename: S
authors.initials: S
authors.lastname: Sebire
authors.forename: A A
authors.initials: AA
authors.lastname: Montgomery
authors.forename: T J
authors.initials: TJ
authors.lastname: Peters
authors.forename: D J
authors.initials: DJ
authors.lastname: Sharp
authors.forename: N
authors.initials: N
authors.lastname: Jackson
authors.forename: K
authors.initials: K
authors.lastname: Fitzsimons
authors.forename: C M
authors.initials: CM
authors.lastname: Dayan
authors.forename: R C
authors.initials: RC
authors.lastname: Andrews
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D008076:Cholesterol, HDL / Q000097:blood; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000378:metabolism* / Q000628:therapy*; D004739:England; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D050177:Overweight / Q000150:complications; D010349:Patient Compliance; D057185:Sedentary Behavior; D013997:Time Factors; D055815:Young Adult
chemical_list: D008076:Cholesterol, HDL; D007328:Insulin