Tobacco smoking and postoperative outcomes after colorectal surgery

The aim of this study was to delineate the impact of smoking on postoperative outcomes after colorectal resection for malignant and benign processes.

Studies to date have implicated smoking as a risk factor for increased postoperative complications. However, there is a paucity of data on the effects of smoking after colorectal surgery and in particular for malignant compared with benign processes.

The American College of Surgeon's National Surgical Quality Improvement Program (2005-2010) database was queried for patients undergoing elective major colorectal resection for colorectal cancer, diverticular disease, or inflammatory bowel disease. Risk-adjusted 30-day outcomes were assessed and compared between patient cohorts identified as never-smokers, ex-smokers, and current smokers. Primary outcomes of incisional infections, infectious and major complications, and mortality were evaluated using regression modeling adjusting for patient characteristics and comorbidities.

A total of 47,574 patients were identified, of which 26,333 had surgery for colorectal cancer, 14,019 for diverticular disease, and 7222 for inflammatory bowel disease. More than 60% of patients had never smoked, 20.4% were current smokers, and 19.2% were ex-smokers. After adjustment, current smokers were at a significantly increased risk of postoperative morbidity [odds ratio (OR), 1.3; 95% confidence interval (CI), 1.21-1.40] and mortality (OR, 1.5; 95% CI, 1.11-1.94) after colorectal surgery. This finding persisted across malignant and benign diagnoses and also demonstrated a significant dose-dependent effect when stratifying by pack-years of smoking.

Smoking increases the risk of complications after all types of major colorectal surgery, with the greatest risk apparent for current smokers. A concerted effort should be made toward promoting smoking cessation in all patients scheduled for elective colorectal surgery.