Phthalates and Phenols, Leukocyte Telomere Length, and Breast Cancer Risk and Mortality in the Long Island Breast Cancer Study Project
Menée à partir de données d'analyses sanguine et urinaire portant sur 581 témoins et 687 patientes atteintes d'un cancer du sein, cette étude analyse l'effet de la longueur des télomères des leucocytes sur l'association entre une exposition environnementale aux phtalates ou aux phénols et le risque de développer la maladie
Background: Phthalates and phenols from the environment have been inconsistently associated with breast cancer risk or mortality. Studies on the potential modifying role of leukocyte telomere length (LTL), a biomarker of biological aging, on these associations are lacking. Methods: We included 1268 women from the Long Island Breast Cancer Study Project with available data on phthalate and phenol analytes and LTL measurements. Twenty-two phthalate and phenol analytes were measured in spot urines and LTL was measured in blood. The modifying effect of LTL on the associations of individual analyte with breast cancer risk as well as mortalities was estimated using interaction terms between LTL and urinary concentrations of analyte in logistic regression and Cox regression models, respectively. Odds ratios, hazards ratios, and corresponding 95% confidence intervals for a one-unit (ln ug/g creatinine) increase of urinary phthalate/phenol level were estimated at 10th, 50th, and 90th percentiles of LTL. Results: LTL significantly (P<0.05) modified associations between 11 out of 22 of urinary phthalate/phenols analytes and breast cancer risk. An inverse association between phthalate/phenols analytes and breast cancer risk at shorter LTL and a positive association at longer LTL was generally suggested. No modifying effect was found for LTL on the association between these phthalate/phenols analytes and breast cancer mortalities. Conclusions: LTL may modify the associations between phthalate and phenol exposures and breast cancer risk. Impact: This study is the first study that determined the modifying effect of biological aging in the association between environmental chemical exposure and breast cancer risk.