title: Impact of medical therapy on patients with Crohn's disease requiring surgical resection.
abstract: OBJECTIVE
  To evaluate the impact of medical therapy on Crohn's disease patients undergoing their first surgical resection.
  
  
  METHODS
  We retrospectively evaluated all patients with Crohn's disease undergoing their first surgical resection between years 1995 to 2000 and 2005 to 2010 at a tertiary academic hospital (St. Paul's Hospital, Vancouver, Canada). Patients were identified from hospital administrative database using the International Classification of Diseases 9 codes. Patients' hospital and available outpatient clinic records were independently reviewed and pertinent data were extracted. We explored relationships among time from disease diagnosis to surgery, patient phenotypes, medication usage, length of small bowel resected, surgical complications, and duration of hospital stay.
  
  
  RESULTS
  Total of 199 patients were included; 85 from years 1995 to 2000 (cohort A) and 114 from years 2005 to 2010 (cohort B). Compared to cohort A, cohort B had more patients on immunomodulators (cohort A vs cohort B: 21.4% vs 56.1%, P < 0.0001) and less patients on 5-aminosalysilic acid (53.6% vs 29.8%, P = 0.001). There was a shift from inflammatory to stricturing and penetrating phenotypes (B1/B2/B3 38.8% vs 12.3%, 31.8% vs 45.6%, 29.4% vs 42.1%, P < 0.0001). Both groups had similar median time to surgery. Within cohort B, 38 patients (33.3%) received anti-tumor necrosis factor (TNF) agent. No patient in cohort A was exposed to anti-TNF agent. Compared to patients not on anti-TNF agent, ones exposed were younger at diagnosis (anti-TNF vs without anti-TNF: A1/A2/A3 39.5% vs 11.8%, 50% vs 73.7%, 10.5% vs 14.5%, P = 0.003) and had longer median time to surgery (90 mo vs 48 mo, P = 0.02). Combination therapy further extended median time to surgery. Using time-dependent multivariate Cox proportional hazard model, patients who were treated with anti-TNF agents had a significantly higher risk to surgery (adjusted hazard ratio 3.57, 95%CI: 1.98-6.44, P < 0.0001) compared to those without while controlling for gender, disease phenotype, smoking status, and immunomodulator use.
  
  
  CONCLUSIONS
  Significant changes in patient phenotypes and medication exposures were observed between the two surgical cohorts separated by a decade.
authors.affiliation: YT Nancy Fu, Brian Bressler, Division of Gastroenterology, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Y T Nancy
authors.initials: YT
authors.lastname: Fu
authors.affiliation: YT Nancy Fu, Brian Bressler, Division of Gastroenterology, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hong
authors.affiliation: YT Nancy Fu, Brian Bressler, Division of Gastroenterology, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Round
authors.affiliation: YT Nancy Fu, Brian Bressler, Division of Gastroenterology, Department of Medicine, University of British Columbia, St. Paul's Hospital, Vancouver, BC V6Z 1Y6, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Bressler
mesh_terms: D000293:Adolescent; D000328:Adult; D001688:Biological Products / Q000627:therapeutic use; D001955:British Columbia; D016009:Chi-Square Distribution; D003424:Crohn Disease / Q000175:diagnosis / Q000188:drug therapy* / Q000601:surgery*; D013505:Digestive System Surgical Procedures / Q000009:adverse effects; D004359:Drug Therapy, Combination; D005260:Female; D005765:Gastrointestinal Agents / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010641:Phenotype; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001688:Biological Products; D005765:Gastrointestinal Agents; D007155:Immunologic Factors
keywords: Anti-tumor necrosis factor; Biologics; Crohn’s disease; Immunomodulators; Inflammatory bowel disease; Medication; Phenotype; Surgery