title: Prospective cohort study of the relationship of markers of insulin resistance and secretion with weight gain and changes in regional adiposity.
abstract: OBJECTIVE
  To examine whether fasting insulin concentrations and markers of first-phase insulin secretion are associated with weight gain and changes in distribution of adiposity over 4.4y.
  
  
  METHODS
  Longitudinal prospective population-based cohort study of middle-aged Caucasians.
  
  
  METHODS
  767 subjects (40-65y at baseline) were followed up for a mean of 4.4y.
  
  
  METHODS
  75 g oral glucose tolerance test performed at baseline and follow-up. Insulin was measured at fasting, and 30 and 120 min post-glucose load using a highly specific assay.
  
  
  RESULTS
  Fasting insulin levels were correlated with baseline weight (r = 0.32, P<0.001), as was the 30 min insulin incremental response (r = 0.17, P<0.001). Mean weight gain over the 4.4y of follow-up was 2.17 kg (range: -6.17-10.5 kg) for men and 2.49 kg (range: -7.41-12.39 kg) for women. In women, the 30 min insulin incremental response was negatively associated with percentage weight gain (P<0.001), but there was no relationship between fasting insulin levels and weight gain. The baseline fasting insulin was positively correlated with percentage increase in waist- hip ratio (r = 0.12, P = 0.01). In stratified analysis, this relationship was confined to women over the age of 50 y. However, in men, none of these relationships were demonstrable.
  
  
  CONCLUSIONS
  In middle-aged women reduced first-phase insulin secretion was associated with an increased risk of future weight gain, whereas fasting hyperinsulinaemia was associated with an increase in waist-hip ratio over time.
authors.affiliation: Department of Clinical Biochemistry, University of Cambridge, Addenbrookes Hospital, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Gould
authors.forename: D E
authors.initials: DE
authors.lastname: Williams
authors.forename: C D
authors.initials: CD
authors.lastname: Byrne
authors.forename: C N
authors.initials: CN
authors.lastname: Hales
authors.forename: N J
authors.initials: NJ
authors.lastname: Wareham
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001823:Body Composition; D001824:Body Constitution; D015331:Cohort Studies; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance; D000078790:Insulin Secretion; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism*; D011446:Prospective Studies; D012737:Sex Factors; D015430:Weight Gain
chemical_list: D015415:Biomarkers; D007328:Insulin