title: Contrast-induced acute kidney injury and clinical outcomes after intra-arterial and intravenous contrast administration: risk comparison adjusted for patient characteristics by design.
abstract: BACKGROUND
  Direct comparisons between risk of contrast induced acute kidney injury (CI-AKI) after intra-arterial versus intravenous contrast administration are scarce. We estimated and compared the risk of CI-AKI and its clinical course after both modes of contrast administration in patients who underwent both.
  
  
  METHODS
  One hundred seventy patients who received both intra-arterial and intravenous contrast injections within one year between 2001 and 2010 were included. Primary outcome was occurrence of CI-AKI. Secondary outcomes were duration of hospital stay, the need for dialysis, recovery of renal function, and mortality.
  
  
  RESULTS
  The risk of CI-AKI was 24/170 (14.0%, 95% CI 9.6-20.2) after intra-arterial contrast injection versus 20/170 (11.7%, 95% CI 7.7-17.5) after intravenous contrast administration, which led to a relative risk of 1.2 (95% CI 0.7-2.1). None of the patients had a need for dialysis. Median duration of hospital stay in CI-AKI patients was 15.0 days (2.5-97.5, percentile 1-92) after intra-arterial and 15.5 days (2.5-97.5, percentile 0-38) after intravenous contrast procedures. Renal function recovered after CI-AKI in 13/24 after intra-arterial and in 10/20 patients after intravenous contrast administration. Mortality risks in CI-AKI patients were slightly higher than in non-CI-AKI patients, hazard ratios 1.6 (95% CI 0.7-3.7) for intra-arterial and 1.7 (95% CI 0.7-4.4) for intravenous contrast administration, adjusted for confounders.
  
  
  CONCLUSIONS
  The risk of CI-AKI, and its clinical course was similar after intra-arterial and intravenous contrast media administration, after adjustment by design for patient-related risk factors.
authors.affiliation: Department of Thrombosis and Haemostasis, Leiden University Medical Center (LUMC), Leiden, The Netherlands; Department of Nephrology, LUMC, Leiden, The Netherlands. j.kooiman@lumc.nl
authors.forename: Judith
authors.initials: J
authors.lastname: Kooiman
authors.forename: Pum A
authors.initials: PA
authors.lastname: Le Haen
authors.forename: Gülçin
authors.initials: G
authors.lastname: Gezgin
authors.forename: Jean-Paul P
authors.initials: JP
authors.lastname: de Vries
authors.forename: Doeke
authors.initials: D
authors.lastname: Boersma
authors.forename: Harald F
authors.initials: HF
authors.lastname: Brulez
authors.forename: Yvo W
authors.initials: YW
authors.lastname: Sijpkens
authors.forename: Aart J
authors.initials: AJ
authors.lastname: van der Molen
authors.forename: Suzanne C
authors.initials: SC
authors.lastname: Cannegieter
authors.forename: Jaap F
authors.initials: JF
authors.lastname: Hamming
authors.forename: Menno V
authors.initials: MV
authors.lastname: Huisman
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000628:therapy; D003287:Contrast Media / Q000008:administration & dosage / Q000009:adverse effects*; D017023:Coronary Angiography / Q000009:adverse effects* / Q000379:methods; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D015994:Incidence; D007269:Injections, Intra-Arterial; D007275:Injections, Intravenous; D007902:Length of Stay; D009426:Netherlands / Q000453:epidemiology; D006435:Renal Dialysis; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D003287:Contrast Media