Race moderates the relationship between obesity and colorectal cancer screening in women.

OBJECTIVE: To determine if the relationship between obesity and usage of colorectal cancer (CRC) screening in women varies when stratifying by race. METHODS: Using nationally representative data from the 2005 National Health Interview Survey, we examined the relationship between obesity and CRC screening for white and African-American women aged 50 and older. Screening usage variables indicated if a woman was up-to-date for any CRC screening test, colonoscopy, or FOBT. We used multivariable logistic regression models that included interaction terms to determine if race moderates the obesity-screening relationship. We also calculated adjusted up-to-date colonoscopy rates using direct standardization to model covariates. RESULTS: The relationship between obesity and screening differed by race for any CRC screening test (P = 0.04 for interaction) and for colonoscopy (P = 0.01 for interaction), but not for FOBT. Obese white women had a lower adjusted colonoscopy rate (30.2%, 95% CI 25.9-34.8) than non-obese white women (39.1%, 95% CI 36.1-42.2). Obese African-American women, on the other hand, had a higher adjusted colonoscopy rate (41.2%, 95% CI 31.6-51.4) than their non-obese counterparts (35.6%, 95% CI 28.3-43.6). Overall, adjusted colonoscopy rates were lowest among obese white women. CONCLUSIONS: Obesity is associated with lower CRC screening rates in white, but not African-American women.

Duke Scholars

Author Michael Patrick Pignone Medicine, General Internal Medicine