Stepwise Relationship Between Components of Metabolic Syndrome and Risk of Colorectal Adenoma in a Taiwanese Population Receiving Screening Colonoscopy

Background/Purpose: Metabolic syndrome (MS) is a cluster of diseases related to insulin resistance and is an important cardiovascular risk factor. In addition, MS has been linked to some malignancies, including colorectal cancer. Colon adenoma is a well-established pre-malignant lesion of colorectal cancer. The aim of this study was to determine the effect of various components of MS on the risk of colorectal adenoma. Methods: From October 2004 to April 2006, 3106 subjects who had undergone complete colonoscopy for health examinations at the hospital were enrolled. MS was defined according to the modified National Cholesterol Education Program Adult Treatment Panel Ill definition for South Asians and Chinese. Multivariate logistic regression was used to analyze the association between components of MS and colorectal adenoma. Results: Of the 3106 subjects, the mean age was 47.1 +/- 10.8 years and there were 397 (13%) subjects with pathologically proven colorectal adenoma. Male sex, old age (>= 50 years), current smokers, and abdominal obesity were associated with increasing risk of colorectal adenoma. MS was associated with increased risk of colorectal adenoma (odds ratio: 1.71, 95% confidence interval: 1.34-2.71), and this risk increased with the number of metabolic components. Multiple and synchronous adenomas of the proximal and distal colon were positively associated with MS. Conclusion: Subjects with metabolic syndrome have increased risk of developing colorectal adenoma. Screening colonoscopy for prevention of colorectal adenoma might be warranted when abdominal obesity or more than three components of MS are present.