Association Between Exposure to Environmental Tobacco Smoke at the Workplace and Risk for Developing a Colorectal Adenoma: A Cross-Sectional Study

Purpose: A colorectal adenoma (CRA) is a well-defined precursor to colorectal cancer (CRC). Additionally, smoking is a potent risk factor for developing a CRA, as well as CRC. However, the association between exposure to environmental tobacco smoke (ETS) and the risk for developing a CRA has not yet been fully evaluated in epidemiologic studies. We performed a cross-sectional analysis on the association between exposure to ETS at the workplace and the risk for developing a CRA. Methods: The study was conducted on subjects who had undergone a colonoscopy at a health promotion center from January 2012 to December 2012. After descriptive analyses, overall and subgroup analyses by smoking status were performed by using a multivariate logistic regression. Results: Among the 1,129 participants, 300 (26.6%) were diagnosed as having CRAs. Exposure to ETS was found to be associated with CRAs in all subjects (fully adjusted odds ratio [OR], 1.95; 95% confidence interval [CI], 1.08-2.44; P = 0.001). In the subgroup analysis, exposure to ETS in former smokers increased the risk for developing a CRA (fully adjusted OR, 4.44; 95% CI, 2.07-9.51; P < 0.001). Conclusion: Exposure to occupational ETS at the workplace, independent of the other factors, was associated with increased risk for developing a CRA in all subjects and in former smokers. Further retrospective studies with large sample sizes may be necessary to clarify the causal effect of this relationship.