Long-term Diet and Biomarker Changes after a Short-term Intervention among Hispanic Breast Cancer Survivors: The ¡Cocinar Para Su Salud! Randomized Controlled Trial

Abstract

Background: Among Hispanic breast cancer survivors, we examined the long-term effects of a short-term culturally based dietary intervention on increasing fruits/vegetables (F/V), decreasing fat, and changing biomarkers associated with breast cancer recurrence risk.

Methods: Spanish-speaking women (n = 70) with a history of stage 0-III breast cancer who completed treatment were randomized to ¡Cocinar Para Su Salud! (n = 34), a culturally based 9-session program (24 hours over 12 weeks, including nutrition education, cooking classes, and food-shopping field trips), or a control group (n = 36, written dietary recommendations for breast cancer survivors). Diet recalls, fasting blood, and anthropometric measures were collected at baseline, 6, and 12 months. We report changes between groups at 12 months in dietary intake and biomarkers using 2-sample Wilcoxon t tests and generalized estimating equation (GEE) models.

Results: At 12 months, the intervention group compared with the control group reported higher increases in mean daily F/V servings (total: +2.0 vs. -0.4; P < 0.01), and nonsignificant decreases in the percentage of calories from fat (-2.2% vs. -1.1%; P = 0.69) and weight (-2.6 kg vs. -1.5 kg; P = 0.56). Compared with controls, participants in the intervention group had higher increases in plasma lutein (+20.4% vs. -11.5%; P < 0.01), and borderline significant increases in global DNA methylation (+0.8% vs. -0.5%; P = 0.06).

Conclusions: The short-term ¡Cocinar Para Su Salud! program was effective at increasing long-term F/V intake in Hispanic breast cancer survivors and changed biomarkers associated with breast cancer recurrence risk.

Impact: It is possible for short-term behavioral interventions to have long-term effects on behaviors and biomarkers in minority cancer patient populations. Results can inform future study designs. Cancer Epidemiol Biomarkers Prev; 25(11); 1491-502. ©2016 AACR.

Figure 1. Heat map of associations between changes in dietary components and changes in anthropometric, metabolic, inflammatory and DNA methylation markers

Each pixel represents the percent change in cancer-related biomarkers on the x-axis associated with every 10% change in dietary factors on the y-axis, adjusted for the baseline value of the dietary factor of interest, randomization arm and stratification. These estimated changes in cancer-related biomarkers were labelled as “+” if the change is in a favorable direction that reflects improvements in biomarkers, or “−” if otherwise. The darkness of color represents the magnitude of percent changes in cancer-related biomarkers. Our results showed that increases in fruit/vegetable intake were generally beneficial as measured by these cancer-related biomarkers, while increases in dietary fat generally led to unfavorable changes.