title: Systematic oral hydration with water is similar to parenteral hydration for prevention of contrast-induced nephropathy: an updated meta-analysis of randomised clinical data.
abstract: Contrast-induced nephropathy (CIN) is the third most common cause of hospital-acquired kidney injury and is related to increased long-term morbidity and mortality. Adequate intravenous (IV) hydration has been demonstrated to lessen its occurrence. Oral (PO) hydration with water is inexpensive and readily available but its role for CIN prevention is yet to be determined.
  
  
  
  PubMed, EMBASE and the Cochrane Central register of controlled trials (CENTRAL) databases were searched until April 2015 and studies were selected using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. All randomised clinical trials with head-to-head comparison between PO and IV hydration were included.
  
  
  
  A total of 5 studies with 477 patients were included in the analysis, 255 of those receiving PO water. The incidence of CIN was statistically similar in the IV and PO arms (7.7% and 8.2%, respectively; relative risk 0.97; 95% CI 0.36 to 2.94; p=0.95). The incidence of CIN was statistically similar in the IV and PO arms in patients with chronic kidney disease and with normal renal function. Rise in creatinine at 48-72 h was lower in the PO hydration group compared with IV hydration (pooled standard mean difference 0.04; 95% CI 0.03 to 0.06; p<0.001; I(2)=62%).
  
  
  
  Our meta-analysis shows that systematic PO hydration with water is at least as effective as IV hydration with saline to prevent CIN. PO hydration is cheaper and more easily administered than IV hydration, thus making it more attractive and just as effective.
authors.affiliation: Division of Cardiovascular Diseases, Department of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas , USA.
authors.forename: Shiv Kumar
authors.initials: SK
authors.lastname: Agarwal
authors.affiliation: Division of Cardiology, Department of Internal Medicine , Ochsner Clinic Foundation , New Orleans, Louisiana , USA.
authors.forename: Sameh
authors.initials: S
authors.lastname: Mohareb
authors.affiliation: Department of Public Health , Icahn School of Medicine at Mount Sinai , New York, New York , USA.
authors.forename: Achint
authors.initials: A
authors.lastname: Patel
authors.affiliation: Division of Nephrology, Department of Medicine , Icahn School of Medicine at Mount Sinai , New York, New York , USA.
authors.forename: Rabi
authors.initials: R
authors.lastname: Yacoub
authors.affiliation: Saint Luke's Mid America Heart Institute , Kansas City, Missouri , USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: DiNicolantonio
authors.affiliation: Department of Medicine , Icahn School of Medicine at Mount Sinai , New York, New York , USA.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Konstantinidis
authors.affiliation: Department of Public Health , New York Medical College , Valhalla, New York , USA.
authors.forename: Ambarish
authors.initials: A
authors.lastname: Pathak
authors.affiliation: Division of Cardiovascular Diseases, Department of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas , USA.
authors.forename: Shailesh
authors.initials: S
authors.lastname: Fnu
authors.affiliation: Division of Rheumatology, Department of Medicine , Vanderbilt University Medical Center , Nashville, Tennessee , USA.
authors.forename: Narender
authors.initials: N
authors.lastname: Annapureddy
authors.affiliation: Department of Medicine , St Lukes Roosevelt Hospital Center at Mount Sinai , New York, New York , USA.
authors.forename: Priya K
authors.initials: PK
authors.lastname: Simoes
authors.affiliation: Division of Critical Care , Kokilaben Dhirubhai Ambani Hospital and Medical Research Institute , Mumbai, Maharashtra , India.
authors.forename: Sunil
authors.initials: S
authors.lastname: Kamat
authors.affiliation: Department of Medicine , St Lukes Roosevelt Hospital Center at Mount Sinai , New York, New York , USA.
authors.forename: Georges
authors.initials: G
authors.lastname: El-Hayek
authors.affiliation: Division of Cardiology, Department of Internal Medicine , Ochsner Clinic Foundation , New Orleans, Louisiana , USA.
authors.forename: Ravi
authors.initials: R
authors.lastname: Prasad
authors.affiliation: Division of Nephrology, Department of Internal Medicine , Ochsner Clinic Foundation , New Orleans, Louisiana , USA.
authors.forename: Damodar
authors.initials: D
authors.lastname: Kumbala
authors.affiliation: Jackson Memorial Hospital , Miami, Florida , USA.
authors.forename: Rhanderson M
authors.initials: RM
authors.lastname: Nascimento
authors.affiliation: Division of Cardiology, Department of Internal Medicine , Ochsner Clinic Foundation , New Orleans, Louisiana , USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Reilly
authors.affiliation: Division of Nephrology, Department of Medicine , Icahn School of Medicine at Mount Sinai , New York, New York , USA.
authors.forename: Girish N
authors.initials: GN
authors.lastname: Nadkarni
authors.affiliation: Division of Cardiology, Department of Internal Medicine , Ochsner Clinic Foundation , New Orleans, Louisiana , USA.
authors.forename: Alexandre M
authors.initials: AM
authors.lastname: Benjo