Postoperative Crohn's Disease Recurrence Risk and Optimal Biologic Timing After Temporary Diversion Following Ileocolic Resection.

Abstract

Postoperative recurrence of Crohn's disease (CD) is common. While most patients undergo resection with undiverted anastomosis (UA), some individuals also have creation of an intended temporary diversion (ITD) with an ileostomy followed by ostomy takedown (OT) due to increased risk of anastomotic complications. We assessed the association of diversion with subsequent CD recurrence risk and the influence of biologic prophylaxis timing to prevent recurrence in this population. This was a retrospective cohort study of CD patients who underwent ileocolic resection between 2009 and 2020 at a large quaternary health system. Patients were grouped by continuity status after index resection (primary anastomosis or ITD). The outcomes of the study were radiographic, endoscopic, and surgical recurrence as well as composite recurrence postoperatively (after OT in the ITD group). Propensity score-weighted matching was performed based on risk factors for diversion and recurrence. Multivariable regression and a Cox proportional hazards model adjusting for recurrence risk factors were used to assess association with outcomes. Subgroup analysis in the ITD group was performed to assess the impact of biologic timing relative to OT (no biologic, biologic before OT, after OT) on composite recurrence. A total of 793 CD patients were included (mean age 38 years, body mass index 23.7kg/m2, 52% female, 23% active smoker, 50% penetrating disease). Primary anastomosiswas performed in 67.5% (n = 535) and ITD in 32.5% (n = 258; 79% loop, 21% end) of patients. Diverted patients were more likely to have been males and to have had penetrating and perianal disease, prior biologic use, lower body mass index, and lower preoperative hemoglobin and albumin (all P < .01). After a median follow-up of 44 months, postoperative recurrence was identified in 83.3% patients (radiographic 40.4%, endoscopic 39.5%, surgical 13.3%). After propensity score matching and adjusting for recurrence risk factors, no significant differences were seen between continuity groups in radiographic (adjusted hazard ratio [aHR], 1.32; 95% confidence interval [CI], 0.91-1.91) or endoscopic recurrence (aHR, 1.196; 95% CI, 0.84-1.73), but an increased risk of surgical recurrence was noted in the ITD group (aHR, 1.61; 95% CI, 1.02-2.54). Most (56.1%) ITD patients started biologic prophylaxis after OT, 11.4% before OT, and 32.4% had no postoperative biologic prophylaxis. Biologic prophylaxis in ITD was associated with younger age (P < .001), perianal disease (P = .04), and prior biologic use (P < .001) but not in recurrence (P = .12). Despite higher rates of objective disease activity identified before OT, biologic exposure before OT was not associated with a significant reduction in composite post-OT recurrence compared with starting a biologic after OT (52% vs 70.7%; P = 0.09). Diversion of an ileocolic resection is not consistently associated with a risk of postoperative recurrence and should be performed when clinically appropriate. Patients requiring diversion at time of ileocolic resection are at high risk for recurrence, and biologic initiation prior to stoma reversal may be considered.