title: Free leptin index and PAPP-A: a first trimester maternal serum screening test for pre-eclampsia.
abstract: BACKGROUND
  Prophylaxis with low-dose aspirin may reduce the risk of pre-eclampsia (PE) if introduced in first trimester. The performance of first trimester maternal serum screening for PE using free leptin index (fLI) and PAPP-A, where fLI = leptin/leptin soluble receptor was studied.
  
  
  METHODS
  First trimester serum samples from 126 PE pregnancies and 289 control pregnancies were studied. fLI and PAPP-A were converted into gestational age and maternal weight independent log MoM values of PAPP-A and fLI. The screening performance of markers was studied by receiver-operator-characteristics curves. The performance of population screening was estimated by Monte Carlo simulation.
  
  
  RESULTS
  fLI was significantly (p < 0.001) elevated [mean log MoM 0.2165 (SD: 0.2604)] compared to controls [mean log MoM -0.0368 (SD: 0.3132)] and PAPP-A was significantly (p < 0.001) reduced [mean log MoM -0.0133 (SD: 0.2661)] compared to controls [mean log MoM 0.0474 (SD: 0.2521)] in PE pregnancies. There was no correlation between fLI and PAPP-A in control or PE pregnancies. Combined fLI and PAPP-A screening for PE had estimated population detection rates of 22% and 35% for false positives rates of 6% and 12%, respectively.
  
  
  CONCLUSIONS
  Combining PAPP-A and fLI improves screening performance for PE compared to single marker screening.
authors.affiliation: Department of Clinical Biochemistry and Immunology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Paula L
authors.initials: PL
authors.lastname: Hedley
authors.forename: Sophie
authors.initials: S
authors.lastname: Placing
authors.forename: Karen
authors.initials: K
authors.lastname: Wøjdemann
authors.forename: Anting Liu
authors.initials: AL
authors.lastname: Carlsen
authors.forename: Anne-Cathrine
authors.initials: AC
authors.lastname: Shalmi
authors.forename: Karin
authors.initials: K
authors.lastname: Sundberg
authors.forename: Ann
authors.initials: A
authors.lastname: Tabor
authors.forename: Michael
authors.initials: M
authors.lastname: Christiansen
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D020738:Leptin / Q000097:blood*; D008403:Mass Screening; D011225:Pre-Eclampsia / Q000097:blood* / Q000175:diagnosis*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011266:Pregnancy-Associated Plasma Protein-A / Q000032:analysis*; D011295:Prenatal Care; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D020738:Leptin; D011266:Pregnancy-Associated Plasma Protein-A