title: Comparison between copeptin and vasopressin in a population from the community and in people with chronic kidney disease.
abstract: BACKGROUND
  Vasopressin plays a central role in water homeostasis but it has also been recognized to be associated with adverse effects in several chronic diseases. Recently, copeptin has been increasingly used as a surrogate for vasopressin, as they are co-secreted, and copeptin is easier to measure. However, the relationship between plasma concentrations of copeptin (P(cop)) and vasopressin (P(vp)) has only been studied in relatively small numbers of selected people.
  
  
  OBJECTIVE
  This study sought to evaluate the relationship between P(vp) and P(cop) in a community-based population and in people with chronic kidney disease (CKD).
  
  
  METHODS
  P(vp), P(cop), and urinary osmolarity (Uosm) were compared in 500 participants of the DESIR study, and in 83 ambulatory people with CKD.
  
  
  RESULTS
  Median [interquartile range] of P(cop) and P(vp) in the DESIR study were 4.13 [3.58] pmol/L and 0.92 [1.93] pmol/L, respectively. Log-transformed P(cop) and P(vp) concentrations correlated significantly and positively (r = 0.686, P < .001) and they correlated inversely with estimated U(osm) (P < .001). Copeptin explained only approximately half of the vasopressin variation. In CKD, P(cop) and P(vp) both increased with decreasing estimated glomerular filtration rate (eGFR), but P(cop) increased much faster than P(vp). The P(cop)/P(vp) ratios in the lower and upper quintile groups of eGFR were 14.3 [18.3] and 5.3 [4.5], P < .001, respectively.
  
  
  CONCLUSIONS
  This study in a normal population, the largest ever with measurements of both peptides, shows that copeptin and vasopressin concentrations correlated well. But their relationship is distorted in CKD, suggesting that the peptide clearances differ when the renal function is impaired.
authors.affiliation: Centre de Recherche des Cordeliers, (R.R., L.F., N.B., F.F., G.V., M.M., L.B.) INSERM, 75005 Paris, France; Service d'Endocrinologie (R.R., M.M), Diabétologie et Nutrition, DHU FIRE, Hôpital Bichat Assistance Publique-Hôpitaux de Paris, 75018 Paris, France; Université Pierre et Marie Curie (N.B., L.B.), 75005 Paris, France; Université Paris Diderot (R.R., F.F., M.M.), 75013 Paris, France; Service de Néphrologie (P.J.), Hôpital Necker, 75015 Paris, France; IRSA (O.L.), LA Riche, France; INSERM Center for Research in Epidemiology and Population Health (B.B.), Epidemiology of Diabetes, Obesity and Chronic Kidney Disease Over the Life course, 94805 Villejuif, France; Université Paris Sud (B.B.), 91400 Villejuif, France; and Service de Néphrologie (D.G.B.), Hôpital du Sacré-Coeur, Université de Montréal, QC H3T 1J4 Montreal, Canada.
authors.forename: Ronan
authors.initials: R
authors.lastname: Roussel
authors.forename: Léopold
authors.initials: L
authors.lastname: Fezeu
authors.forename: Michel
authors.initials: M
authors.lastname: Marre
authors.forename: Gilberto
authors.initials: G
authors.lastname: Velho
authors.forename: Frédéric
authors.initials: F
authors.lastname: Fumeron
authors.forename: Paul
authors.initials: P
authors.lastname: Jungers
authors.forename: Olivier
authors.initials: O
authors.lastname: Lantieri
authors.forename: Beverley
authors.initials: B
authors.lastname: Balkau
authors.forename: Nadine
authors.initials: N
authors.lastname: Bouby
authors.forename: Lise
authors.initials: L
authors.lastname: Bankir
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Bichet
mesh_terms: D000328:Adult; D000368:Aged; D004326:Drinking; D005260:Female; D005919:Glomerular Filtration Rate; D006020:Glycopeptides / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D051436:Renal Insufficiency, Chronic / Q000097:blood*; D014667:Vasopressins / Q000097:blood*
chemical_list: D006020:Glycopeptides; C048197:copeptins; D014667:Vasopressins