title: Risk of post-ERCP pancreatitis with placement of self-expandable metallic stents.
abstract: BACKGROUND
  There are conflicting data on the risk of post-ERCP pancreatitis (PEP) related to self-expandable metallic stents (SEMSs).
  
  
  OBJECTIVE
  To compare rates of PEP in patients who undergo biliary drainage with SEMSs or polyethylene stents (PSs).
  
  
  METHODS
  Retrospective, cohort study.
  
  
  METHODS
  Tertiary-care medical center.
  
  
  METHODS
  This study involved patients undergoing ERCP for malignant biliary obstruction between January 2005 and October 2008.
  
  
  METHODS
  First-time placement of a SEMS or PS for biliary decompression.
  
  
  METHODS
  Early post-ERCP complications, particularly PEP.
  
  
  RESULTS
  We identified 544 eligible patients, 248 SEMSs (102 covered), and 296 PSs. The etiology of malignant biliary obstruction was similar between groups, with 55% from pancreatic cancer. The frequency of PEP was significantly higher in the SEMS group (7.3%) versus the PS group (1.3%) (OR 5.7 [95% CI, 1.9-17.1]). On univariate analysis, patient age of <40 years, a history of PEP, and at least 1 pancreatic duct injection were also significant predictors of PEP, whereas female sex and having pancreatic cancer were not. When significant variables were added to a multiple-predictor regression model, the odds of PEP from SEMS placement increased to 6.8 (95% CI, 2.2, 21.4). However, the frequency of PEP was similar between covered (6.9%) and uncovered (7.5%) SEMSs (OR 0.9 [CI, 0.3-2.4]). Purported SEMS-specific risk factors, including the use of cSEMSs, overlapping SEMSs, or having a biliary sphincterotomy were not found to be significant contributors to the higher risk.
  
  
  CONCLUSIONS
  Retrospective design.
  
  
  CONCLUSIONS
  After we controlled for confounding variables, the frequency of PEP was significantly higher with placement of a SEMS compared with a PS. Rates of PEP were comparable with use of covered and uncovered SEMSs.
authors.affiliation: Division of Gastroenterology, Washington University, St Louis School of Medicine, St Louis, Missouri, USA. gcote@iupui.edu
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Coté
authors.forename: Nitin
authors.initials: N
authors.lastname: Kumar
authors.forename: Michael
authors.initials: M
authors.lastname: Ansstas
authors.forename: Steven A
authors.initials: SA
authors.lastname: Edmundowicz
authors.forename: Sreenivasa
authors.initials: S
authors.lastname: Jonnalagadda
authors.forename: Daniel K
authors.initials: DK
authors.lastname: Mullady
authors.forename: Riad R
authors.initials: RR
authors.lastname: Azar
mesh_terms: D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects*; D002779:Cholestasis / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D019299:Decompression, Surgical / Q000379:methods*; D006801:Humans; D008670:Metals; D010190:Pancreatic Neoplasms / Q000150:complications; D010195:Pancreatitis / Q000209:etiology*; D020959:Polyethylene; D011474:Prosthesis Design; D012189:Retrospective Studies; D018570:Risk Assessment; D015607:Stents / Q000009:adverse effects*
chemical_list: D008670:Metals; D020959:Polyethylene