title: Hypertension is an independent risk factor for contrast nephropathy after percutaneous coronary intervention.
abstract: BACKGROUND
  The administration of radiographic contrast agents is an important cause of acute renal failure. We hypothesised that hypertension is an independent risk factor for the development of contrast nephropathy in patients undergoing percutaneous coronary intervention.
  
  
  METHODS
  1383 consecutive patients scheduled for elective or emergency percutaneous coronary intervention were randomly assigned to receive isotonic or half-isotonic hydration. Contrast nephropathy was defined as a rise in serum creatinine of at least 44 micromol/l (0.5 mg/dl) within 48 h of the procedure. Hypertension was defined as self-reported history of treated or untreated diagnosed high blood pressure.
  
  
  RESULTS
  The prevalence of hypertension was 63%. Patients with hypertension were significantly older, were more often female, smoked less and had a higher incidence of 3-vessel disease than patients without hypertension. The estimated glomerular filtration rate was slightly lower in hypertensive patients. There was no difference in preventive hydration regimen, type and quantity of contrast medium used, or quantity of intravenous fluids given. Contrast nephropathy developed in 17 of 874 hypertensive patients (2%) compared to 2 of 509 patients (0.4%) without hypertension (p = 0.016). When contrast nephropathy was defined as a 25% rise in baseline creatinine, the disease developed in 103 patients (12%) with and 36 patients (7%) without hypertension (p = 0.005). After adjustment for confounders, arterial hypertension remained an independent predictor of contrast nephropathy (odds ratio 4.6, 95% CI 1.0-20.5, p = 0.046).
  
  
  CONCLUSIONS
  Hypertension is an independent risk factor for the development of contrast nephropathy. Further preventive strategies to lower the incidence of contrast nephropathy in hypertensive patients are warranted.
authors.affiliation: Department of Cardiology, University Hospital Basel, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Conen
authors.forename: Gerd
authors.initials: G
authors.lastname: Buerkle
authors.forename: André P
authors.initials: AP
authors.lastname: Perruchoud
authors.forename: Heinz J
authors.initials: HJ
authors.lastname: Buettner
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000139:chemically induced / Q000453:epidemiology*; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003287:Contrast Media / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D005260:Female; D005440:Fluid Therapy / Q000379:methods; D005919:Glomerular Filtration Rate; D006801:Humans; D006973:Hypertension; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D003287:Contrast Media; D003404:Creatinine