Abstract 1875: Development of a dietary inflammation score and its association with incident, sporadic colorectal adenoma

Abstract

Abstract It is now well established that inflammation is linked to colorectal carcinogenesis and other chronic diseases. The ability to characterize specific dietary and lifestyle components as having pro- or anti-inflammatory effects is a promising area of cancer prevention. We developed a “dietary inflammation score” based on associations of independent dietary components with plasma C-reactive protein (CRP) in the combined Markers of Adenomatous Polyps (MAPs) case-control studies, and investigated the association of the score with incident, sporadic colorectal adenoma in the same population. First, we excluded individuals who regularly took non-steroidal anti-inflammatory drugs (NSAIDs) and multivitamins, and among those remaining (n = 369) calculated the multivariable-adjusted associations of the individual dietary components with CRP, used the strengths of associations as weights, and summed the weighted dietary components to create an overall summary dietary inflammation score. Food components were included in the score based on biological plausibility and previous literature, and included four categories of meat, nuts, pepper, coffee, tea, high- and low-fat dairy products, refined and whole grains, and twelve botanical categories. The crude odds ratio (OR) for the association of the highest dietary score tertile with log-transformed CRP was 1.92 (95% confidence interval [CI]: 1.13, 3.27); after adjusting for age, sex, total energy intake, and lifestyle inflammation score category, the OR was 1.89 (95% CI: 1.06, 3.36). The association tended to be stronger among older individuals, males, and adenoma cases. The overall score was more strongly associated with CRP than was any individual dietary component. Next, to assess the association of the dietary inflammation score with adenomas, we used the entire MAPs population (n = 188 cases and 325 controls)– including the regular NSAID and multivitamin users. The crude OR for the association of the highest dietary score tertile with incident adenoma was 1.30 (95% CI: 0.84, 2.02), an association that tended to be stronger among men and those who regularly took aspirin or other NSAIDs. Multivariable adjustment did not appreciably change these estimates. The results from this pilot study suggest that diet may contribute to systemic levels of inflammation, and support further investigation of a dietary inflammation score with colorectal neoplasms and other chronic diseases in larger studies. Citation Format: Ashley C. Holmes, Roberd M. Bostick. Development of a dietary inflammation score and its association with incident, sporadic colorectal adenoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1875. doi:10.1158/1538-7445.AM2015-1875