Better postdiagnosis diet quality is associated with reduced risk of death among postmenopausal women with invasive breast cancer in the women's health initiative.
BACKGROUND
Few studies have evaluated whether adherence to dietary recommendations is associated with mortality among cancer survivors. In breast cancer survivors, we examined how postdiagnosis Healthy Eating Index (HEI)-2005 scores were associated with all-cause and cause-specific mortality.


METHODS
Our prospective cohort study included 2,317 postmenopausal women, ages 50 to 79 years, in the Women's Health Initiative's Dietary Modification Trial (n = 1,205) and Observational Study (n = 1,112), who were diagnosed with invasive breast cancer and completed a food frequency questionnaire after being diagnosed. We followed women from this assessment forward. We used Cox proportional hazards models to estimate multivariate-adjusted HRs and 95% confidence intervals (CI) for death from any cause, breast cancer, and causes other than breast cancer, according to HEI-2005 quintiles.


RESULTS
Over 9.6 years, 415 deaths occurred. After adjustment for key covariates, women consuming better quality diets had a 26% lower risk of death from any cause (HRQ4:Q1, 0.74; 95% CI, 0.55-0.99; Ptrend = 0.043) and a 42% lower risk of death from non-breast cancer causes (HRQ4:Q1, 0.58; 95% CI, 0.38-0.87; Ptrend = 0.011). HEI-2005 score was not associated with breast cancer death (HRQ4:Q1, 0.91; 95% CI, 0.60-1.40; Ptrend = 0.627). In analyses stratified by tumor estrogen receptor (ER) status, better diet quality was associated with a reduced risk of all-cause mortality among women with ER(+) tumors (n = 1,758; HRQ4:Q1, 0.55; 95% CI, 0.38-0.79; Ptrend = 0.0009).


CONCLUSIONS
Better postdiagnosis diet quality was associated with reduced risk of death, particularly from non-breast cancer causes.


CONCLUSIONS
Breast cancer survivors may experience improved survival by adhering to U.S. dietary guidelines.
Authors' Affiliations: Applied Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland; Division of Preventive Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Division of Research, Kaiser Permanente of Northern California, Oakland, California; Department of Social and Preventive Medicine, School of Public Health and Health Professions, University at Buffalo, Buffalo, New York; Wake Forest School of Medicine, Division of Public Health Sciences, Winston-Salem, North Carolina; and Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington.
Stephanie M
SM
George
Rachel
R
Ballard-Barbash
James M
JM
Shikany
Bette J
BJ
Caan
Jo L
JL
Freudenheim
Candyce H
CH
Kroenke
Mara Z
MZ
Vitolins
Shirley A
SA
Beresford
Marian L
ML
Neuhouser
D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality*; D015331:Cohort Studies; D004032:Diet / Q000592:standards / Q000706:statistics & numerical data*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008875:Middle Aged; D010349:Patient Compliance; D017698:Postmenopause; D011446:Prospective Studies; D016387:Women's Health