Diet quality, inflammation, and quality of life in breast cancer survivors : a cross-sectional analysis of pilot study data / Tonya S. Orchard, Rebecca R. Andridge, Lisa D. Yee, Maryam B. Lustberg

Background Modifiable lifestyle factors, such as diet quality, could reduce inflammation and improve quality of life (QOL) in breast cancer survivors, but data are inconclusive. Objective To determine whether diet quality, as measured by Healthy Eating Index-2010 (HEI-2010) score, is associated with inflammation, health status, or functional outcomes affecting QOL in survivors of early-stage breast cancer. Design This is a cross-sectional, secondary analysis of baseline data collected from breast cancer survivors after completion of primary therapy and before random assignment to a pilot nutritional intervention aimed at reducing side effects of aromatase inhibitor treatment. Participants/setting Participants were 44 postmenopausal women with stage I to III endocrine receptor-positive breast cancer receiving outpatient care at a midwestern cancer center between November 2011 and October 2013. Main outcome measures Primary outcomes were serum proinflammatory cytokines (interleukin-6 [IL-6], IL-17, and tumor necrosis factor-α receptor 2 [TNFR-2]). Secondary outcomes included QOL measured by the Stanford Health and Disability Questionnaire and the Functional Assessment of Cancer Therapy-Breast with Endocrine Subscale. Statistical analyses performed Pearson correlation coefficients (r) and linear regression models were used to evaluate the relationship of dietary variables with inflammatory cytokines and QOL measures. Results A higher overall HEI-2010 score (healthier diet) was associated with lower IL-6 (r=−0.46; P=0.002) and TNFR-2 (r=−0.41; P=0.006); however, associations were attenuated by body mass index (BMI) (IL=6 [r=−0.26; P=0.10]; TNFR-2 [r=−0.30; P=0.06]). In women with prior chemotherapy, a higher HEI-2010 score was strongly associated with lower IL-6 (r=−0.67; P=0.009) and TNFR-2 (r=−0.59; P=0.03) after BMI adjustment. There were no significant correlations between HEI-2010 score and QOL measures after adjustment for BMI. Conclusions These data suggest the need for more rigorous investigation into the relationship of diet quality, BMI, and inflammation in breast cancer survivors.

Nutrition.