Is metabolic syndrome a risk factor for colorectal adenoma?

Background and Aims: Epidemiologic studies provide evidence for a link between obesity or diabetes and the risk for colorectal cancer. However, there is a lack of information about the relationship between metabolic syndrome and colorectal adenoma. Therefore, we investigated whether metabolic syndrome is a risk factor for colorectal adenoma. Methods: We did a study for consecutive subjects who underwent colonoscopy as a screening exam at the Center for Health Promotion, Samsung Medical Center, from March 2004 to December 2005. According to the modified ATP III criteria, metabolic syndrome was diagnosed. We classified a total of 2,531 subjects into the adenoma group (n = 731) and the control group (n = 1,800), including normal colonoscopic finding, nonpolyp benign lesions, or histologically confirmed hyperplastic polyp. Results: The prevalence for metabolic syndrome was 17% in the adenoma group and 11% in the control group. On the multiple logistic regression analyses, metabolic syndrome was found to be associated with an increased risk of colorectal adenoma (odds ratio, 1.51; 95% confidence interval, 1.18-1.93). Also, waist circumference among the individual components of metabolic syndrome was an independent risk factor for colorectal adenoma. An increased risk for metabolic syndrome was more evident for proximal than distal colon, for multiple (≥3), and for advanced adenoma in the adenoma group. Conclusion: Metabolic syndrome was associated with colorectal adenoma. Abdominal obesity of the individual components of metabolic syndrome was an important risk factor for colorectal adenoma.