title: Contrast-associated acute kidney injury in the critically ill: systematic review and Bayesian meta-analysis.
abstract: OBJECTIVE
  Critically ill patients, among whom acute kidney injury is common, are often considered particularly vulnerable to iodinated contrast medium nephrotoxicity. However, the attributable incidence remains uncertain given the paucity of observational studies including a control group. This study assessed acute kidney injury incidence attributable to iodinated contrast media in critically ill patients based on new data accounting for sample and effect size and including a control group.
  
  
  METHODS
  Systematic review of studies measuring incidence of acute kidney injury in critically ill patients following contrast medium exposure compared to matched unexposed patients. Patient-level meta-analysis implementing a Bayesian nested mixed effects multiple logistic regression model.
  
  
  RESULTS
  Ten studies were identified; only four took into account the baseline acute kidney injury risk, three by patient matching (560 patients). Objective meta-analysis of these three studies (vague and impartial a priori hypothesis concerning attributable acute kidney injury risk) did not find that iodinated contrast media increased the incidence of acute kidney injury (odds ratio 0.95, 95% highest posterior density interval 0.45-1.62). Bayesian analysis demonstrated that, to conclude in favor of a statistically significant incidence of acute kidney injury attributable to contrast media despite this observed lack of association, one's a priori belief would have to be very strongly biased, assigning to previous uncontrolled reports 3-12 times the weight of evidence strength provided by the matched studies including a control group.
  
  
  CONCLUSIONS
  Meta-analysis of matched cohort studies of iodinated contrast medium exposure does not support a significant incidence of acute kidney injury attributable to iodinated contrast media in critically ill patients.
authors.affiliation: Médecine Intensive Réanimation, Centre Hospitalier Régional et Universitaire de Tours, 37044, Tours, France. stephanehrmann@gmail.com.|Faculté de Médecine, Université François Rabelais, Tours, France. stephanehrmann@gmail.com.
authors.forename: Stephan
authors.identifier: http://orcid.org/0000-0001-6221-4467
authors.initials: S
authors.lastname: Ehrmann
authors.affiliation: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA.|Department of Veterans Affairs Medical Center, Miami, FL, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Quartin
authors.affiliation: Department of Biostatistics, University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Hobbs
authors.affiliation: Réanimation Chirurgicale Polyvalente, Service d'Anesthésie-Réanimation, Hôpital Laënnec, Centre Hospitalier Universitaire, Nantes, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Robert-Edan
authors.affiliation: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA.|Department of Veterans Affairs Medical Center, Miami, FL, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Cely
authors.affiliation: Division of Pediatric Nephrology and Hypertension, University of Texas Health Science Center-Houston, Houston, TX, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Bell
authors.affiliation: Department of Biostatistics, University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA.
authors.forename: Genevieve
authors.initials: G
authors.lastname: Lyons
authors.affiliation: Réanimation et USC Médico-chirurgicale, Hôpital Tenon, Assistance Publique, Hôpitaux de Paris, 75970, Paris, France.|INSERM UMR 1153, ECSTRA Team, Paris, France.|Saint Michael's Hospital, Interdepartmental Division of Critical Care, University of Toronto, Toronto, Canada.
authors.forename: Tai
authors.initials: T
authors.lastname: Pham
authors.affiliation: Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA.|Department of Veterans Affairs Medical Center, Miami, FL, USA.
authors.forename: Roland
authors.initials: R
authors.lastname: Schein
authors.affiliation: Research Medical Library, University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Geng
authors.affiliation: Réanimation Chirurgicale Polyvalente, Service d'Anesthésie-Réanimation, Hôpital Laënnec, Centre Hospitalier Universitaire, Nantes, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Lakhal
authors.affiliation: Department of Radiology, University of Texas M.D. Anderson Cancer Center, Houston, TX, 77030, USA.
authors.forename: Chaan S
authors.initials: CS
authors.lastname: Ng
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy*; D061605:Administration, Intravenous; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001499:Bayes Theorem; D015331:Cohort Studies; D003287:Contrast Media / Q000009:adverse effects*; D003422:Critical Care / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D007455:Iodine / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D057216:Propensity Score; D006435:Renal Dialysis / Q000706:statistics & numerical data*; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*
chemical_list: D003287:Contrast Media; D007455:Iodine
keywords: Contrast media (MeSH: D003287); Drug-related side effects and adverse reactions (MeSH D064420); Intensive care units (MeSH D007362); Percutaneous coronary interventions (MeSH: D062645); Tomography scanners, X-ray computed (MeSH: D015898)