title: Risk Factors for Marginal Ulcer After Gastric Bypass Surgery for Obesity: A Population-based Cohort Study.
abstract: OBJECTIVE
  This study aimed to assess risk factors for developing marginal ulcer (MU) after gastric bypass (GBP) surgery for obesity.
  
  
  BACKGROUND
  MU is a common and potentially serious complication of GBP surgery, little is known about its etiology.
  
  
  METHODS
  This population-based cohort study of GBP in 2006-2011 evaluated MU in relation to diabetes, hyperlipidemia, hypertension, chronic obstructive pulmonary disease (COPD), ulcer history, use of proton pump inhibitors (PPIs), aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and selective serotonin reuptake inhibitors (SSRIs). Multivariable Cox proportional hazard regression models estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for confounding.
  
  
  RESULTS
  Among 20,294 GBP patients, diabetes and peptic ulcer history entailed statistically significantly increased risk of MU (HR = 1.26, 95% CI 1.03-1.55 and HR  =  2.70, 95% CI 1.81-4.03), although hyperlipidemia, hypertension, and COPD did not. PPI users had an increased HR of MU (HR  =  1.37, 95% CI 1.17-1.60). Aspirin and NSAID consumption less than or equal to median entailed decreased HRs of MU (HR  =  0.56, 95% CI 0.37-0.86 and HR  =  0.30, 95% CI 0.24-0.38), although aspirin and NSAID users more than median had an increased risk and no association with MU, respectively (HR  =  1.90, 95% CI 1.41-2.58 and HR  =  0.90, 95% CI 0.76-1.87). The use of SSRI less than or equal to median had a decreased risk of MU (HR  =  0.50, 95% CI 0.37-0.67), although use more than median entailed increased HR (HR  =  1.26, 95% CI 1.01-1.56).
  
  
  CONCLUSIONS
  Diabetes and peptic ulcer history seem to be risk factors for MU, but not hyperlipidemia, hypertension, or COPD. Limited doses of aspirin, NSAIDs, and SSRIs might not increase the risk, although higher doses of aspirin do. The association with PPI could be due to confounding by indication.
authors.affiliation: *Upper Gastrointestinal Surgery, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden †Department of Upper Gastrointestinal Surgery, South Hospital, Stockholm, Sweden ‡Department of Epidemiology and Biostatistics, Imperial College London, London, United Kingdom §Division of Cancer Studies, King's College London, London, United Kingdom.
authors.forename: Emma
authors.initials: E
authors.lastname: Sverdén
authors.forename: Fredrik
authors.initials: F
authors.lastname: Mattsson
authors.forename: Anders
authors.initials: A
authors.lastname: Sondén
authors.forename: Ted
authors.initials: T
authors.lastname: Leinsköld
authors.forename: Wenjing
authors.initials: W
authors.lastname: Tao
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Lu
authors.forename: Jesper
authors.initials: J
authors.lastname: Lagergren
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000601:surgery*; D010437:Peptic Ulcer / Q000209:etiology*; D011183:Postoperative Complications / Q000209:etiology*; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D016896:Treatment Outcome