Impact of smoking on disease phenotype and postoperative outcomes for Crohn's disease patients undergoing surgery

Aim: Whether smoking affects disease distribution, phenotype, and perioperative outcomes for Crohn's disease (CD) patients undergoing surgery is not well characterized. The aim of this study is to evaluate the impact of smoking on disease phenotype and postoperative outcomes for CD patients undergoing surgery Methods: Prospectively collected data of CD patients undergoing colorectal resection were evaluated. CD patients who were current smokers (CS) were compared to nonsmokers (NS) and ex-smokers (ES) for disease phenotype, anatomic site involved, procedures performed, postoperative outcomes, and quality of life using the Cleveland Global Quality of Life instrument (CGQL). Results: Of 691 patients with a diagnosis of CD requiring surgery 314 were classified as CS, 330 as NS, and 47 as ES. CS and ES in comparison to NS were significantly older at diagnosis of Crohn's disease (mean, 29.3 vs. 29.2 vs. 26.3 years) (P = 0.001) and older at the time of primary surgery (mean, 42.9 vs. 48.4 vs. 39 years) (P = 0.001) with a greater frequency of diabetes. In all groups requiring surgery, there was a significant change in disease phenotype from the time of diagnosis to surgical intervention. The predominant phenotype at diagnosis was inflammatory which changed to stricturing and penetrating as the dominant phenotypes at time of surgery. All groups had a significant improvement in CGQL scores post-surgery with the greatest benefit observed in NS. Postoperative complications and 30-day readmission rates were similar between all groups. Conclusions: The findings of this study show that in patients with CD, disease phenotype changes over time. This occurs independent of smoking. Smoking does not appear to predispose to complications for CD patients undergoing surgery. CS and ES have a persistently reduced quality of life in comparison to NS post-surgery.