Aim: 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.
Conclusion: Significant changes in patient phenotypes and medication exposures were observed between the two surgical cohorts separated by a decade.
Keywords: Anti-tumor necrosis factor; Biologics; Crohn’s disease; Immunomodulators; Inflammatory bowel disease; Medication; Phenotype; Surgery.