ASPO Abstracts
Red Blood Cell Polyunsaturated Fatty Acid Composition and Mortality Following Breast Cancer: Results from the Women's Healthy Eating and Living (WHEL) Study
Category: Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2023
Abstract Body:
Purpose: To examine the associations between red blood cell (RBC) composition of polyunsaturated fatty acids (PUFAs) and mortality among women with breast cancer. Methods: This nested case-control study included 1,104 women from the Women's Healthy Eating and Living Study, a randomized controlled trial of a plant-based dietary change on breast cancer survival. Cases were women who died from any cause (n=290) from 1995 to 2006. Controls were women who were alive at the end of follow-up matched to cases on age at diagnosis, years since randomization, intervention group, and stage (n=814). RBC fatty acid composition was measured in blood samples collected at baseline using gas chromatography and included the proportions of four n-3 and seven n-6 PUFAS. We examined each PUFA individually as well as factor analysis-derived factors in association with all-cause and breast cancer-specific mortality using conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results: In fully-adjusted models, all-cause mortality ORs were elevated among women with PUFAs >median (versus ≤median) for alpha-linolenic acid (ALA, C18:3n3; OR=1.56; 95%CI=1.14-2.14) and for linolenic acid (LnA, C18:2n6, OR=1.54; 95%CI=1.15-2.07), and breast cancer-specific mortality ORs were elevated for LnA (OR=1.72, 95%CI=1.24-2.38) and gamma-linolenic acid (GLA, C18:3n6; OR=1.40; 95%CI=0.97-2.00). Factor 1 [arachidonic acid, C20:4n6; adrenic acid, C22:4n6; and docosapentaenoic acid, C22:5n6] scores >median (versus ≤median) were associated with lower odds of all-cause (OR=0.72; 95%CI=0.53-0.98) and breast cancer-specific (OR=0.67; 95%CI=0.47-0.94) mortality, and Factor 4 [ALA and GLA] scores >median (versus ≤median) were associated with increased odds of breast cancer-specific mortality (OR=1.42; 95%CI=1.01-2.01). Additionally, 1-SD increase in Factor 4 scores were associated with ORs of 1.22 (95%CI=1.04-1.42) for all-cause mortality and 1.24 (95%CI=1.05-1.47) for breast cancer-specific mortality. Conclusions: RBC PUFA composition profiles are associated with all-cause and breast cancer-specific mortality risk among women with breast cancer.
Keywords: breast cancer mortality; red blood cell composition; polyunsaturated fatty acids