Aim: To evaluate the role of CARD15 mutations and smoking in the main events of Crohn's disease (CD).
Patients and methods: A total of 182 patients with CD were included in a prospective study in order to evaluate the role of CARD15 mutations and smoking in the main outcomes of disease course: first operation and surgical recurrence. The following variables were evaluated in a univariable and multivariable analysis: age, sex, site of disease, pattern, smoking habit, extraintestinal manifestations, duration of disease, and CARD15 mutation. The Kaplan-Meier method for survival curves and Cox model for multivariable analysis were, respectively, used.
Results: A total of 110 patients were operated on and 32 were reoperated on. The 7-yr cumulative free rate of surgery was 42% (95% CI 34-51%). At multivariate analysis only stricturing and penetrating pattern were predictors of surgery (HR 1.7, 95% CI 1-2.8; HR 3.2, CI 1.8-5.5, respectively). The 7-yr cumulative free rate of reoperation was 75% (95% CI 0.52-0.88). At multivariable analysis in the model with any CARD15 mutation, only smoking habit at diagnosis (HR 3.6, 95% CI 1.4-9.1) was predictive of surgical recurrence. When single mutations were considered in the model smoking (HR 4.2, 95% CI 1.8-10.1) and L1007fs mutation (HR 2.9, 95% CI 1.1-7.3) were predictive of reoperation.
Conclusions: In CD, smoking predicts recurrence after surgery. The role of CARD15 mutations in the clinical course of CD remains undefined.