Pharmaceutical Sciences Faculty Publications
Reproducibility of Fifteen Urinary Estrogens and Estrogen Metabolites Over a 2- to 3-Year Period in Premenopausal Women
Document Type
Article
Publication Date
11-1-2009
Journal Title
Cancer Epidemiology, Biomarkers & Prevention
ISSN
1538-7755
Volume
18
Issue
11
First Page
2860
Last Page
2868
DOI
10.1158/1055-9965.EPI-09-0591
PubMed ID
19843676
PubMed Central® ID
PMC2783292
Abstract
Endogenous estrogens play an integral role in the etiology of breast, endometrial, and, possibly, ovarian cancers. Estrogen metabolism yields products that are potentially both estrogenic and genotoxic, yet individual metabolic patterns are just beginning to be explored in epidemiologic studies. Within the Nurses' Health Study II, we examined reproducibility of 15 urinary estrogens and estrogen metabolites (EM) among 110 premenopausal women with three luteal-phase urine samples collected over 3 years. EM were measured by a recently developed high-performance liquid chromatography-tandem mass spectrometry (LC-MS(2)) method with high sensitivity, specificity, and precision. We assessed Spearman correlations and intraclass correlation coefficients (ICC) across the three samples. Correlations between urinary estrone or estradiol and EM were only modest (r = 0.1-0.5). The 2- and 4-hydroxylation pathways were highly correlated (r = 0.9) but weakly inversely correlated with the 16-hydroxylation pathway (r = -0.2). Within-woman reproducibility over time was fairly high for the three pathways, with ICCs ranging from 0.52 (16-hydroxylation pathway) to 0.72 (2-hydroxylation pathway). ICCs were similarly high for 2-catechols and the individual catechols (ICCs = 0.58-0.72). Individual and grouped methylated 2-catechols had fairly high ICCs (0.51-0.62), but methylated 4-catechols had low ICCs (0.14-0.27). These data indicate that, in general, urinary EM levels vary substantially among individuals compared with intraindividual variability. Within-person reproducibility over time for most EM measures is comparable to or better than that for well-vetted biomarkers such as plasma cholesterol and, in postmenopausal women, estradiol.
Keywords
Chromatography, liquid, estradiol, estrogens, estrone, tandem mass spectrometry
Recommended Citation
Eliassen, A. Heather; Ziegler, Regina G.; Rosner, Bernard; Veenstra, Timothy D.; Roman, John M.; Xu, Xia; and Hankinson, Susan E., "Reproducibility of Fifteen Urinary Estrogens and Estrogen Metabolites Over a 2- to 3-Year Period in Premenopausal Women" (2009). Pharmaceutical Sciences Faculty Publications. 273.
https://digitalcommons.cedarville.edu/pharmaceutical_sciences_publications/273
