Healthy Eating Index-2010 and Mediterranean-Style Dietary Pattern Score and the risk of colorectal cancer and adenoma: a case-control study

Background: Several studies have examined the relationship between diet quality indices and colorectal cancer (CRC). However, data on the association of these indices and colorectal adenomas (CRA) as a precursor of CRC are scarce. Our objective was to investigate the association of Healthy Eating Index (HEI-2010) and Mediterranean-Style Dietary Pattern Score (MSDPS) with CRC and CRA risk. Methods: This is a hospital-based case-control study including 259 cases (129 CRC and 130 CRA patients) and 240 controls with non-neoplastic conditions. Dietary intake of subjects was examined using a valid and reliable food frequency questionnaire. The HEI-2010 and MSDPS were then calculated based on a-priori methods. Multivariate logistic regression analyses were conducted to estimate the relationship between HEI-2010 and MSDPS and the risk of CRC and CRA. Results: After adjustment for confounders, compared with the first tertiles, the highest tertiles of HEI-2010 and MSDPS were significantly associated with lower odds of CRC (OR = 0.04; 95% CI = 0.01-0.12, OR = 0.19; 95% CI = 0.09-0.38, respectively). Similarly, the highest tertiles of HEI-2010 (OR = 0.04; 95% CI = 0.08-0.32) and MSDPS (OR = 0.19; 95% CI = 0.17-0.58) were associated with reduced odds of CRA compared to the lowest tertiles. Conclusion: The findings of this study suggested that a high-quality diet assessed by HEI-2010 and MSDPS is inversely associated with the risk of CRC and CRA.