Azathioprine or ileocolic resection for steroid-dependent terminal ileal Crohn's disease? A Markov analysis.
BACKGROUND
The objective of this study was to determine whether initial azathioprine therapy, followed by ileocolic resection if azathioprine fails, or initial ileocolic resection without a trial of azathioprine is the preferred treatment strategy in steroid-dependent, terminal ileal Crohn's disease.


METHODS
A Markov, decision analytic model was developed to simulate a 36-month course for a patient with steroid-dependent, terminal ileal Crohn's disease who would initially take azathioprine or have ileocolic resection. Clinically important outcomes in the model included side effects and effectiveness of azathioprine and postoperative complications, mortality, and recurrence following ileocolic resection. The probabilities and utilities for these variables were derived from previously published studies.


RESULTS
Initial azathioprine therapy offered a relatively small benefit of 0.45 quality-adjusted life-months over initial ileocolic resection. The model was sensitive to utility for being symptom-free on azathioprine and utility for being symptom-free postoperatively.


CONCLUSIONS
Initial azathioprine therapy and initial ileocolic resection are both reasonable treatment strategies in this setting. The preferred treatment strategy is highly dependent on the quality of life that can be achieved with each treatment option. Therefore, individual response and symptom control with each treatment must be strongly considered in this treatment decision.
Kennedy
Erin D
ED
Department of Surgery and Medicine, University of Toronto, the Samuel Lunenfield Research Institute, Mount Sinai Hospital, Toronto, Canada.
Urbach
David R
DR
Krahn
Murray D
MD
Steinhart
A Hillary
AH
Cohen
Zane
Z
McLeod
Robin S
RS
D000328:Adult; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001379:Azathioprine / Q000009:adverse effects / Q000627:therapeutic use*; D015331:Cohort Studies; D003082:Colectomy / Q000009:adverse effects / Q000401:mortality / Q000523:psychology; D003131:Combined Modality Therapy; D003424:Crohn Disease / Q000453:epidemiology / Q000523:psychology / Q000628:therapy*; D003663:Decision Trees; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D007079:Ileitis / Q000453:epidemiology / Q000523:psychology / Q000628:therapy*; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D008017:Life Expectancy; D008297:Male; D008390:Markov Chains; D009017:Morbidity; D018579:Patient Selection; D011241:Prednisone / Q000627:therapeutic use; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013997:Time Factors; D016896:Treatment Outcome
D000893:Anti-Inflammatory Agents; D007166:Immunosuppressive Agents; D001379:Azathioprine; D011241:Prednisone