Healthy eating index and breast cancer risk among Malaysian women

Healthy Eating Index-2005 (HEI-2005), an index-based dietary pattern, has been shown to predict the risk of chronic diseases among Americans. This study aims to examine the ability of HEI-2005 in predicting the probability for risk of premenopausal and postmenopausal breast cancer among Malaysian women. Data from a case-control nutritional epidemiology study among 764 participants including 382 breast cancer cases and 382 healthy women were extracted and scored. Multivariate odds ratios (OR) with 95% confidence intervals (CI) were used to evaluate the relationship between the risk of breast cancer and quartiles (Q) of HEI-2005 total scores and its component, whereas the risk prediction ability of HEI-2005 was investigated using diagnostics analysis. The results of this study showed that there is a significant reduction in the risk of breast cancer, with a higher HEI-2005 total score among premenopausal women (OR Q1 vs. Q4=0.34, 95% CI; 0.15-0.76) and postmenopausal women (OR Q1 vs. Q4=0.20, 95% CI; 0.06-0.63). However, HEI-2005 has a sensitivity of 56-60%, a specificity of 55-60%, and a positive predictive value and negative predictive value of 57-58%, which indicates a moderate ability to predict the risk of breast cancer according to menopausal status. The breast cancer incidence observed poorly agrees with risk outcomes from HEI-2005 as shown by low κ statistics (κ=0.15). In conclusion, although the total HEI-2005 scores were associated with a risk of breast cancer among Malaysian women, the ability of HEI-2005 to predict risk is poor as indicated by the diagnostic analysis. A local index-based dietary pattern, which is disease specific, is required to predict the risk of breast cancer among Malaysian women for early prevention.