BMI and the risk of colorectal adenoma in African-Americans

Obesity is associated with the activation of the molecular pathways that increase the risk of colorectal cancer. Increasing body mass index may accelerate the development of adenomatous polyps, the antecedent lesion of colorectal cancer. The aim of this study was to assess the BMI effect on the risk of colonic polyp and adenoma in African-American.

The records of 923 patients who underwent colonoscopy were examined. Demographic and clinical data were collected before colonoscopy. Polyp and adenoma diagnosis were confirmed by pathology examinations.

Overall, 43% of the patients were male, median age was 57 years and 77% had BMI ≥ 25.0 kg/m(2) . The frequency of colorectal polyps and adenomas were 61 and 35%, respectively. BMI ≥ 25.0 (OR = 1.61, 95% CI = 1.14-2.26), smoking (OR = 1.61, 95% CI = 1.15-2.26) and history of colon polyps (OR = 1.64, 95% CI = 1.09-2.47) were associated with higher risk of colon polyp. BMI ≥ 25.0 (OR = 1.81, 95% CI = 1.24-2.62), age (OR = 1.04, 95% CI = 1.02-2.05 for each year), male gender (OR = 1.38, 95% CI = 1.02-1.86), and smoking (OR = 1.73, 95% CI = 1.23-2.42) were associated with higher risk of colon adenoma.

Male and overweight African-Americans are at higher risk of colorectal adenoma. The findings of this study could be applied for risk stratification and modifying the colorectal cancer prevention including screening guideline in African Americans.