Plasma Levels of Dichlorodiphenyldichloroethene (DDE) and Dichlorodiphenyltrichloroethane (DDT) and Survival following Breast Cancer in the Carolina Breast Cancer Study

Citation

Parada, Humberto, Jr.; Sun, Xuezheng; Tse, Chiu-Kit J.; Engel, Lawrence S.; Olshan, Andrew F.; & Troester, Melissa A. (2019). Plasma Levels of Dichlorodiphenyldichloroethene (DDE) and Dichlorodiphenyltrichloroethane (DDT) and Survival following Breast Cancer in the Carolina Breast Cancer Study. Environment International, 125, 161-171. PMCID: PMC6448589

Abstract

OBJECTIVES: To examine plasma levels of dichlorodiphenyldichloroethene (DDE) and dichlorodiphenyltrichloroethane (DDT) in association with survival among women with breast cancer who participated in a population-based case-control study.
METHODS: Participants included 456 white and 292 black women from the Carolina Breast Cancer Study Phase I who were diagnosed with primary invasive breast cancer from 1993 to 1996, and who had available DDE/DDT and lipid measurements from blood samples obtained on average 4.1months after diagnosis. Using the National Death Index, we identified 392 deaths (210 from breast cancer) over a median follow-up of 20.6years. We used Cox regression to estimate covariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and breast cancer-specific 5-year mortality, and 20-year mortality conditional on 5-year survival, for lipid-standardized DDE and DDT levels. Associations stratified by race and estrogen receptor (ER) status were also examined.
RESULTS: The highest versus lowest DDE tertile and the highest vs non-detectable DDT quantile were associated with HRs of 1.95 (95% CI=1.31-2.92) and 1.64 (95% CI=1.10-2.44), respectively, for 20-year conditional all-cause mortality. DDE levels above versus below the median were associated with a HR of 1.69 (95% CI=1.06-2.68) for 20-year conditional breast cancer-specific mortality among women overall, and HRs were 2.36 (95% CI=1.03-5.42) among black women and 1.57 (95% CI=0.86-2.89) among white women (PInteraction=0.42), and 3.24 (95% CI=1.38-7.58) among women with ER(-) tumors and 1.29 (95% CI=0.73-2.28) among women with ER(+) tumors (PInteraction=0.03).
CONCLUSION: Exposure to DDE/DDT may adversely impact overall and breast cancer-specific survival. DDE exposure may contribute to the racial disparities in breast cancer survival.

URL

http://dx.doi.org/10.1016/j.envint.2019.01.032

Reference Type

Journal Article

Year Published

2019

Journal Title

Environment International

Author(s)

Parada, Humberto, Jr.
Sun, Xuezheng
Tse, Chiu-Kit J.
Engel, Lawrence S.
Olshan, Andrew F.
Troester, Melissa A.

PMCID

PMC6448589

ORCiD

Olshan - 0000-0001-9115-5128