title: A single preoperative FGF23 measurement is a strong predictor of outcome in patients undergoing elective cardiac surgery: a prospective observational study.
abstract: BACKGROUND
  Several scoring systems have been developed to predict postoperative mortality and complications in patients undergoing cardiac surgery. However, these computer-based calculations are time- and cost-intensive. A simple but highly predictive test for postoperative risk would be of clinical benefit with respect to increasingly scarce hospital resources. We therefore assessed the predictive power of fibroblast growth factor 23 (FGF23) measurement compared with an established scoring system.
  
  
  METHODS
  We conducted a prospective interdisciplinary observational study at the Saarland University Medical Centre that included 859 patients undergoing elective cardiac surgery between January 2010 and March 2011 with a median follow-up after discharge of 822 days. We compared a single preoperative measurement of FGF23 as a prognostic tool with the 18 parameters comprising EuroSCORE II with respect to postoperative mortality, acute kidney injury, non-occlusive mesenteric ischemia, clinical course and long-term outcome.
  
  
  RESULTS
  Preoperative FGF23 levels were highly predictive of postoperative outcome and complications. The predictive value of FGF23 for mortality in the receiver operating characteristic curve was greater than the EuroSCORE II (area under the curve: 0.800 versus 0.725). Moreover, preoperative FGF23 independently predicted postoperative acute kidney injury and non-occlusive mesenteric ischemia comparably to the EuroSCORE II. Finally, FGF23 was found to be an independent predictor of clinical course parameters, including duration of surgery, ventilation time and length of stay.
  
  
  CONCLUSIONS
  In patients undergoing elective cardiac surgery, a simple preoperative FGF23 measurement is a powerful indicator of surgical mortality, postoperative complications and long-term outcome. Its utility compares to the widely used EuroSCORE II.
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. timo.speer@uks.eu.
authors.forename: Timo
authors.initials: T
authors.lastname: Speer
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Saarland University Medical Centre, Homburg/Saar, Germany. heinrich.groesdonk@uks.eu.|Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Centre, Homburg/Saar, Germany. heinrich.groesdonk@uks.eu.
authors.forename: Heinrich V
authors.initials: HV
authors.lastname: Groesdonk
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. beate.zapf@web.de.
authors.forename: Beate
authors.initials: B
authors.lastname: Zapf
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. quitscheentchen99@web.de.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Buescher
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. miriam_beyse@web.de.
authors.forename: Miriam
authors.initials: M
authors.lastname: Beyse
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. lau.lau@gmx.net.
authors.forename: Laura
authors.initials: L
authors.lastname: Duerr
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. stellagewert@googlemail.com.
authors.forename: Stella
authors.initials: S
authors.lastname: Gewert
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. patriziakrauss@arcor.de.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Krauss
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. aaron.poppleton@gmail.com.
authors.forename: Aaron
authors.initials: A
authors.lastname: Poppleton
authors.affiliation: Institute for Medical Biometry, Epidemiology and applied Medical Informatics, Saarland University Medical Centre, Homburg/Saar, Germany. stefan.wagenpfeil@uks.eu.
authors.forename: Stefan
authors.initials: S
authors.lastname: Wagenpfeil
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. danilo.fliser@uks.eu.
authors.forename: Danilo
authors.initials: D
authors.lastname: Fliser
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Saarland University Medical Centre, Homburg/Saar, Germany. h-j.schaefers@uks.eu.
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Schaefers
authors.affiliation: Department of Internal Medicine, Nephrology and Hypertension, Saarland University Medical Centre, Kirrberger Strasse, D-66424, Homburg/Saar, Germany. matthias.klingele@uks.eu.
authors.forename: Matthias
authors.initials: M
authors.lastname: Klingele
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D006348:Cardiac Surgical Procedures / Q000401:mortality* / Q000639:trends; D015331:Cohort Studies; D017558:Elective Surgical Procedures / Q000401:mortality* / Q000639:trends; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood* / Q000401:mortality*; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods* / Q000639:trends; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23