title: A potential inverse association between insulin-like growth factor I and hypertension in a cross-sectional study.
abstract: OBJECTIVE
  Elevated circulating insulin-like growth factor I (IGF-I) levels increasingly are being implicated as a potential risk factor for the development of some cancers; however, relatively few epidemiologic studies have focused on potential relationships between circulating IGF-I levels and cardiovascular risk factors or cardiovascular disease. Hence, our objective is to examine relationships between IGF-I levels; body mass index (BMI); fasting insulin level; IGF binding protein 1 (IGFBP-1), IGFBP-2, and IGFBP-3 levels; and an array of traditional cardiovascular risk factors.
  
  
  METHODS
  Our analysis included 715 men and women aged 30 to 62 years who participated in the Västerbotten Intervention Project cohort. IGF-I and IGFBP-1, -2, and -3 were measured in stored plasma samples. Cardiovascular risk factors of interest included glucose level (fasting and 2-hour postload), lipid levels (total cholesterol, high-density lipoprotein cholesterol, and triglycerides), blood pressure (systolic and diastolic), and hypertension status. All presented results were adjusted for age, sex, and laboratory batch.
  
  
  RESULTS
  IGF-I quartile was associated inversely with 2-hour glucose level and diastolic blood pressure. There was a stepwise inverse graded association between increasing IGF-I quartile and hypertension, with an odds ratio of 0.51 (95% confidence interval, 0.29-0.90) for hypertension comparing the fourth IGF-I quartile with the first. Further adjusting for BMI and IGFBP-3 level simultaneously strengthened the inverse association, with an odds ratio of 0.42 (95% confidence interval, 0.22-0.80) for hypertension comparing the fourth with the first IGF-I quartile.
  
  
  CONCLUSIONS
  Contrary to positive associations between IGF-I levels and some cancers, our results suggest that IGF-I level may be related inversely to prevalent hypertension, a risk factor for cardiovascular disease.
authors.affiliation: Division of Clinical Epidemiology, University of Texas Health Science Center, San Antonio, TX, USA.
authors.forename: Kelly J
authors.initials: KJ
authors.lastname: Hunt
authors.forename: Annekatrin
authors.initials: A
authors.lastname: Lukanova
authors.forename: Sabina
authors.initials: S
authors.lastname: Rinaldi
authors.forename: Eva
authors.initials: E
authors.lastname: Lundin
authors.forename: Teresa
authors.initials: T
authors.lastname: Norat
authors.forename: Richard
authors.initials: R
authors.lastname: Palmqvist
authors.forename: Pär
authors.initials: P
authors.lastname: Stattin
authors.forename: Elio
authors.initials: E
authors.lastname: Riboli
authors.forename: Göran
authors.initials: G
authors.lastname: Hallmans
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kaaks
mesh_terms: D000328:Adult; D001786:Blood Glucose; D001794:Blood Pressure; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003430:Cross-Sectional Studies; D005215:Fasting / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D007328:Insulin / Q000097:blood; D018969:Insulin-Like Growth Factor Binding Proteins / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D016017:Odds Ratio; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
chemical_list: D001786:Blood Glucose; D007328:Insulin; D018969:Insulin-Like Growth Factor Binding Proteins; D007334:Insulin-Like Growth Factor I; D002784:Cholesterol