Correlations between obesity/metabolic syndrome-related factors and risk of developing colorectal tumors.

Colorectal cancer/adenoma development may correlate with obesity/metabolic syndrome in the Japanese. We sought to clarify the relation between colorectal adenoma prevalence and various factors to develop a better colorectal tumor screening strategy.Of 2668 patients who underwent colonoscopy, medical records of 837 patients (467 men, 370 women; age, 40-80 years) with available data on measured values of body mass index, waist circumference, body fat percentage, and prior history of hypertension, diabetes and hyperlipidemia were reviewed and analyzed.Of these patients, 460 (55.0%) had colorectal tumor or prior history thereof (lesions >=1mm). Multivariate analysis revealed significant differences in gender, age and waist circumference between patients with/without colorectal adenoma, with men at significantly higher risk than women of developing colorectal tumor (OR=2.57, 95% CI: 1.84-4.65; p<0.001). In patients with/without colorectal tumor, age, waist circumference and body fat percentage were significantly different among men, but only age was significantly different among women.Present findings that waist circumference and body fat percentage correlated with prevalence of colorectal tumor among men may contribute to more accurate prediction of colorectal tumor risk and an efficient colorectal cancer screening system.