Obesity and colon polyps in the black women's health study: An opportunity for prevention Free

PL02-01

Objective. Colorectal adenomas are thought to be precursor lesions to colorectal cancer, a leading cause of cancer incidence and mortality in African-American women. Studies suggest that obesity is a risk factor for adenomas in White women, but little is known about the relation in African-American women. We prospectively examined the association between selected anthropometric factors and colorectal polyps in African-American women.
 Research Methods and Procedures. Data were obtained from the Black Women’s Health Study, a prospective cohort study of African-American women. From 1997 to 2003, we followed 33,403 women aged ≥30 years with no prior diagnosis of cancer or polyps. Cox regression was used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for risk of polyps, with adjustment for potential confounders.
 Results. After 211,797 person-years of follow-up, 1,189 cases of colorectal polyps were reported. The IRR comparing women with a current body mass index (BMI) ≥35 to <25 kg/m² was 1.35 (95%CI=1.12-1.62), after adjustment for covariates including waist-to-hip ratio (WHR). Women who gained ≥30 kg since age 18 were 1.76 times as likely as those who gained <5 kg to report polyps (95%CI=1.33-2.33). The IRR comparing the highest (≥0.87) to lowest (<0.71) quintiles of WHR was 1.26 (95%CI=1.04-1.54) after adjustment for covariates including BMI. BMI at age 18, adult height, and waist circumference (BMI-adjusted) were not materially associated with risk.
 Discussion. Weight gain and obesity in adulthood may increase the risk of colorectal polyps in African-American women.