title: Changes in circulating level of IGF-I and IGF-binding protein-1 from the first to second trimester as predictors of preeclampsia.
abstract: OBJECTIVE
  To assess whether circulating IGF-I and IGF-binding protein-1 (IGFBP-1) in the first and second trimester are associated with subsequent risk of preterm and term preeclampsia.
  
  
  METHODS
  Nested case-control study within a cohort of 29 948 pregnant women. Cases were women, who later developed preeclampsia, and controls were randomly selected women, who did not develop preeclampsia. IGF-I and IGFBP-1 were measured with ELISA in maternal blood samples that were collected in the first and second trimesters. We assessed associations of IGF-I and IGFBP-1 concentrations with later development of preterm (before the 37th week of gestation) and term preeclampsia.
  
  
  RESULTS
  An increase in IGF-I from the first to second trimester was associated with higher risk of preterm preeclampsia; the odds ratio (OR) for the highest compared with lowest quartile of increase was 4.9 (95% confidence interval, 1.1-21.8). Low concentrations of IGFBP-1, both in the first and in the second trimesters, were related to higher risk of term preeclampsia (OR 4.0, 95% confidence interval, 1.9-8.4) and moderately increased risk of preterm preeclampsia (OR 2.3, 95% confidence interval, 1.2-4.4).
  
  
  CONCLUSIONS
  The higher risk of preterm preeclampsia related to IGF-I increase may reflect placental disease, whereas low concentrations of IGFBP-1 associated with term preeclampsia may reflect maternal metabolic aberrations, indicating different etiologies in preeclampsia.
authors.affiliation: Department of Public Health, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway. lars.vatten@ntnu.no
authors.forename: Lars J
authors.initials: LJ
authors.lastname: Vatten
authors.forename: Tom I L
authors.initials: TI
authors.lastname: Nilsen
authors.forename: Anders
authors.initials: A
authors.lastname: Juul
authors.forename: Stig
authors.initials: S
authors.lastname: Jeansson
authors.forename: Pål A
authors.initials: PA
authors.lastname: Jenum
authors.forename: Anne
authors.initials: A
authors.lastname: Eskild
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D016017:Odds Ratio; D011225:Pre-Eclampsia / Q000097:blood* / Q000175:diagnosis; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D018970:Insulin-Like Growth Factor Binding Protein 1; D007334:Insulin-Like Growth Factor I