title: Elevated fasting insulin levels increase the risk of abdominal obesity in Korean men.
abstract: OBJECTIVE
  This study was designed to investigate whether an elevated fasting insulin level predicts abdominal obesity.
  
  
  METHODS
  A cohort study was conducted with 13,707 non-obese Korean men. They were categorized into 4 groups according to the quartile of fasting insulin level, and followed up from 2005 to 2010. Incidence rates of obesity were compared among the 4 groups during follow-up, and a Cox proportional hazards model was used to calculate hazard ratios (HRs) for abdominal obesity according to fasting insulin level.
  
  
  RESULTS
  The overall incidence rate of obesity was 16.2%, but the rate increased in proportion to the fasting insulin level (quartiles 1-4: 9.8%, 12.4%, 16.9%, 25.5%, P<0.001). When HR of the 1st quartile was regarded as the reference, HRs for abdominal obesity increased proportionally to baseline fasting insulin level in an unadjusted model. However, after adjustment for covariates, including baseline waist circumference (WC), only in the quartile 4 group was the statistical significance of the association maintained [quartile 2-4; abdominal obesity: 0.89 (0.76-1.02), 1.00 (0.86-1.14) and 1.24 (1.08-1.43), P for trend <0.001].
  
  
  CONCLUSIONS
  Although the risk of incident abdominal obesity was highest in the group with the highest fasting insulin levels, an overall proportional relationship between fasting insulin level and incident abdominal obesity was not found. Additionally, this association was largely accounted for by baseline WC.
authors.affiliation: Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea.
authors.forename: Sung Keun
authors.initials: SK
authors.lastname: Park
authors.affiliation: The Korea Central Cancer Registry, National Cancer Center, Goyang, South Korea.
authors.forename: Chang-Mo
authors.initials: CM
authors.lastname: Oh
authors.affiliation: Department of Internal Medicine, Seoul Paik Hospital, Inje University School of Medicine, Seoul, South Korea.
authors.forename: Taegi
authors.initials: T
authors.lastname: Jung
authors.affiliation: Department of Dermatology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, Seoul, South Korea.
authors.forename: Young-Jun
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Chonbuk National University, College of Arts, Department of Industrial Design, Jeollabuk-do, South Korea.
authors.forename: Ju Youn
authors.initials: JY
authors.lastname: Chung
authors.affiliation: Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul, South Korea. Electronic address: armani131@naver.com.
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Ryoo
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005215:Fasting / Q000097:blood*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D056128:Obesity, Abdominal / Q000097:blood / Q000453:epidemiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D055105:Waist Circumference
chemical_list: D007328:Insulin
keywords: Abdominal obesity; Insulin; Waist circumference