title: Should the arteriovenous fistula be created before starting dialysis?: a decision analytic approach.
abstract: BACKGROUND
  An arteriovenous fistula (AVF) is considered the vascular access of choice, but uncertainty exists about the optimal time for its creation in pre-dialysis patients. The aim of this study was to determine the optimal vascular access referral strategy for stage 4 (glomerular filtration rate <30 ml/min/1.73 m(2)) chronic kidney disease patients using a decision analytic framework.
  
  
  METHODS
  A Markov model was created to compare two strategies: refer all stage 4 chronic kidney disease patients for an AVF versus wait until the patient starts dialysis. Data from published observational studies were used to estimate the probabilities used in the model. A Markov cohort analysis was used to determine the optimal strategy with life expectancy and quality adjusted life expectancy as the outcomes. Sensitivity analyses, including a probabilistic sensitivity analysis, were performed using Monte Carlo simulation.
  
  
  RESULTS
  The wait strategy results in a higher life expectancy (66.6 versus 65.9 months) and quality adjusted life expectancy (38.9 versus 38.5 quality adjusted life months) than immediate AVF creation. It was robust across all the parameters except at higher rates of progression and lower rates of ischemic steal syndrome.
  
  
  CONCLUSIONS
  Early creation of an AVF, as recommended by most guidelines, may not be the preferred strategy in all pre-dialysis patients. Further research on cost implications and patient preferences for treatment options needs to be done before recommending early AVF creation.
authors.affiliation: Division of Nephrology, Kidney Research Center, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada. shiremath@toh.on.ca
authors.forename: Swapnil
authors.initials: S
authors.lastname: Hiremath
authors.forename: Greg
authors.initials: G
authors.lastname: Knoll
authors.forename: Milton C
authors.initials: MC
authors.lastname: Weinstein
mesh_terms: D000368:Aged; D001164:Arteriovenous Fistula; D001166:Arteriovenous Shunt, Surgical / Q000379:methods*; D003198:Computer Simulation; D003657:Decision Making; D003661:Decision Support Techniques; D018450:Disease Progression; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy*; D008390:Markov Chains; D009010:Monte Carlo Method; D011336:Probability; D006435:Renal Dialysis / Q000379:methods*