Risk factors for recurrence of Crohn's disease requiring surgery in patients receiving post-operative anti-tumor necrosis factor maintenance therapy

Objectives: Anti-tumor necrosis factor (TNF) antibodies have shown efficacy in the prevention of recurrence of Crohn's disease after intestinal resection. However, some patients develop surgical recurrence despite this therapy. We aimed to evaluate the risk factors for recurrence of Crohn's disease requiring surgery while receiving post-operative anti-TNF therapy. Methods: We performed a retrospective evaluation of 164 patients who had received post-operative anti-TNF maintenance therapy between 2002 and 2016. We classified Crohn's disease-related re-operation as surgical recurrence and analyzed its risk factors using the Cox proportional hazard model. Results: Of the 164 participants, 128 had received infliximab and 36 had received adalimumab maintenance therapy. We obtained follow-up data over a mean of 60.2 months. The proportion of patients with surgical recurrence at 5 years was 14.9%. The only independent risk factor for surgical recurrence, which we identified was post-operative smoking habit (odds ratio, 5.03; 95% CI, 1.14-12.8; P=0.033). Conclusions: Post-operative smoking may be a significant risk factor for post-operative surgical recurrence of Crohn's disease while receiving anti-TNF maintenance therapy.