Abstract LB-163: Associations of whole food and lifestyle-based inflammation scores with incident, sporadic colorectal adenoma
Authors: Byrd Doratha , Bostick Roberd M. 
Published: August 2018

Colorectal carcinogenesis is mechanistically linked to inflammation, and is highly associated with diet and other lifestyle factors, which in turn can act as sources of chronic inflammation. We developed dietary (DIS), lifestyle (LIS), and overall (OIS) inflammation scores to characterize the aggregate of pro- and anti-inflammatory exposures, and investigated associations of the scores with incident, sporadic colorectal adenoma.

Based on previous literature, we selected a priori 20 components for the DIS, including processed meats, red meats, white meats, fish, nuts, legumes, soy, dairy products, grains, added sugars, saturated/trans fats, leafy greens, citrus, deep-orange/yellow vegetables, cabbage family vegetables, apples/berries, and tomatoes/tomato products. Similarly, for the LIS we selected smoking status, physical activity, alcohol intake, and body mass index. We assessed associations of each score component with a panel of biomarkers of inflammation (CRP, IL-6, IL-8, IL-10) in a subset of 1,101 male and female, black and white participants in the Reasons for Geographic and Racial Differences in Stroke cohort study using multivariable linear regression. The resulting beta coefficients were used to weight each score component.

We used previously collected data from three pooled case-control studies of colorectal adenoma (N = 787 cases and 2,033 controls) in which extensive dietary (via Willett food frequency questionnaires), medical, and lifestyle data were collected. For each study participant, the weighted score components were summed to produce the scores such that a higher score reflected a higher balance of pro- to anti-inflammatory exposures. The scores were categorized according to quintiles of their distributions among the controls, and their associations with adenoma were assessed using unconditional logistic regression.

With increasing levels of each score, there was increasing risk of incident, sporadic adenoma. For those in the highest relative to the lowest quintiles of the DIS, LIS, and OIS, the multivariable-adjusted odds ratios (OR) were 1.4 (95% confidence interval [CI]: 1.0, 1.9; Ptrend = 0.02), 1.9 (95% CI: 1.4, 2.5; Ptrend &lt;0.0001), and 2.6 (95% CI: 1.8, 3.9; Ptrend = &lt;0.0001) respectively. Among those who were overweight/obese or men, the ORs comparing those in the highest relative to the lowest quintile of the DIS were, respectively, 1.8 (95% CI: 1.2, 2.6; Ptrend = 0.003) and 1.8 (95% 1.2, 2.7; Ptrend = 0.007).

These results suggest that diets and lifestyles with a higher balance of pro- to anti-inflammatory exposures may be associated with higher risk for incident, sporadic colorectal adenoma.

Citation Format: Doratha Byrd, Roberd M. Bostick. Associations of whole food and lifestyle-based inflammation scores with incident, sporadic colorectal adenoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-163.