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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #197117

Title: DIET QUALITY IS ASSOCIATED WITH THE RISK OF ESTROGEN RECEPTOR-NEGATIVE BREAST CANCER IN POSTMENOPAUSAL WOMEN

Author
item FUNG, TERESA - SIMMONS COLLEGE
item HU, FRANK - HARVARD SCH PUB HEALTH
item MCCULLOUGH, MARJORIE - AMER CANCER SOCIETY
item NEWBY, PHYLLIS - TUFTS/HNRCA
item WILLETT, WALTER - HARVARD SCH PUB HEALTH
item HOLMES, MICHELLE - HARVARD MEDICAL SCHOOL

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/25/2005
Publication Date: 2/1/2006
Citation: Fung, T.T., Hu, F.B., Mccullough, M.L., Newby, P.K., Willett, W.C., Holmes, M.D. 2006. Diet quality is associated with the risk of estrogen receptor-negative breast cancer in postmenopausal women. Journal of Nutrition. 136(2):466-72.

Interpretive Summary: Emerging evidence suggests that diet quality indices may serve as indicators of disease. However, the ability of these indices to predict breast cancer risk has not been evaluated previously. We assessed the association between several diet quality scores and the risk of breast cancer in postmenopausal women. The indices we used were the Healthy Eating Index (HEI), Alternate Healthy Eating Index (AHEI), Diet Quality Index-Revised (DQI-R), Recommended Food Score (RFS), and the alternate Mediterranean Diet Score (aMed). We calculated diet quality indices from dietary information collected in FFQ administered 5 times between 1984 and 1998 among women in the Nurses' Health Study cohort. Risk estimates were computed using Cox proportional hazards models and adjusted for known risk factors for breast cancer. Separate analyses were conducted for estrogen receptor positive (ER+) and negative (ER-) tumors. We did not observe any association between the diet quality indices and total or ER+ breast cancer risk. However, for ER- breast cancer, women in the highest quintile of the AHEI, the RFS, and the aMED were at a reduced risk of breast cancer compared to women in the lowest quintile of each dietary index. Specifically, relative risks were 0.78 for the AHEI, 0.69 for the RFS, and 0.79 for the aMed. These observations appeared to be the result of an inverse association with the vegetable component of the scores. We concluded that women who scored high in AHEI, RFS, and aMed had a lower risk of ER- breast cancer. The HEI and DQI-R appeared to be of limited value in predicting breast cancer risk.

Technical Abstract: Emerging evidence suggests that diet quality indices may serve as prognostic indicators of disease. However, the ability of these indices to predict breast cancer risk has not been evaluated previously. We assessed the association between several diet quality scores and the risk of breast cancer in postmenopausal women. The indices we used were the Healthy Eating Index (HEI), Alternate Healthy Eating Index (AHEI), Diet Quality Index-Revised (DQI-R), Recommended Food Score (RFS), and the alternate Mediterranean Diet Score (aMed). We calculated diet quality indices from dietary information collected in FFQ administered 5 times between 1984 and 1998 among women in the Nurses' Health Study cohort. Relative risks (RR) were computed using Cox proportional hazards models and adjusted for known risk factors for breast cancer. Separate analyses were conducted for estrogen receptor positive (ER+) and negative (ER-) tumors. Between 1984 and 2002, we documented 3,580 cases of breast cancer, of which 2,367 were ER+, and 575 were ER-. We did not observe any association between the diet quality indices and total or ER+ breast cancer risk. However, for ER- breast cancer, after adjusting for potential confounders, the RR comparing highest to lowest quintiles were 0.78 (95% CI=0.59-1.04, P for trend=0.01) for the AHEI, 0.69 (95% CI=0.51-0.94, P for trend=0.003) for the RFS, and 0.79 (95% CI=0.60-1.03, P for trend=0.03) for the aMed. These observations appeared to be the result of an inverse association (P for trend=0.01) with the vegetable component of the scores. We conclude that women who scored high in AHEI, RFS, and aMed had a lower risk of ER- breast cancer. The HEI and DQI-R appeared to be of limited value in predicting breast cancer risk.