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Background: Uterine leiomyomata, or fibroids, are hormone-dependent neoplasms of the myometrium that can cause severe gynecologic morbidity. In previous studies, incidence of these lesions has been positively associated with exposure to polychlorinated biphenyls (PCBs), a class of persistent endocrine-disrupting chemicals. However, previous studies have been retrospective in design and none has used ultrasound to reduce disease misclassification.Methods: The Study of Environment, Lifestyle, and Fibroids is a prospective cohort of 1,693 reproductive-aged Black women residing in Detroit, Michigan (enrolled during 2010-2012). At baseline and every 20 months for 5 years, women completed questionnaires, provided blood samples, and underwent transvaginal ultrasound to detect incident fibroids. We analyzed 754 baseline plasma samples for concentrations of 24 PCB congeners using a case-cohort study design. We used multivariable Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals for the association between plasma PCB concentrations and ultrasound-detected fibroid incidence over a 5-year period.Results: We observed little association between PCB congener concentrations and fibroid incidence. The HR for a one-standard deviation increase in log-transformed total PCBs was 0.94 (95% CI = 0.78, 1.1). The PCB congener with the largest effect estimate was PCB 187 (HR for a one-standard deviation increase in log-transformed exposure = 0.88, 95% CI = 0.73, 1.1). Associations did not seem to vary strongly across PCB groupings based on hormonal activity.Conclusions: In this cohort of reproductive-aged Black women, plasma PCB concentrations typical of the contemporary general population were not appreciably associated with higher risk of fibroids. [ABSTRACT FROM AUTHOR]

Uterine leiomyomata (UL) are associated with severe reproductive morbidity and are the primary indication for hysterectomy in the United States. A recent prospective cohort study of Black women reported positive associations between intakes of marine-sourced ω-3 fatty acids and UL risk. We examined whether intakes of dietary fat were associated with UL incidence in a 5-year prospective study of premenopausal Black women living in Detroit who underwent serial ultrasound. At baseline (2010–2012) and 20, 40, and 60 months of follow-up, participants underwent transvaginal ultrasound. Among 1,171 UL-free women at baseline, incident UL were detected in 277 women. Cox regression was used to estimate hazard ratios and 95% confidence intervals for the association of dietary fat and UL incidence. Intakes of total fat and saturated, monounsaturated, polyunsaturated, and trans -fat were not appreciably associated with UL incidence. Intake of the marine ω-3 polyunsaturated fatty acid, docosahexaenoic acid, was associated with 49% higher UL incidence (quartile 4 vs. 1: hazard ratio = 1.49, 95% confidence interval: 1.04, 2.14; P for trend = 0.01). Intakes of total marine ω-3 polyunsaturated fatty acids were similarly associated with elevated UL incidence (hazard ratio = 1.35, 95% confidence interval: 0.94, 1.93; P for trend = 0.03). It remains unclear whether the fatty acids or persistent environmental pollutants drive the association. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are a class of lipophilic endocrine-disrupting chemicals with wide industrial use in the U.S. from the 1930s through 1977. Due to their environmental and biological persistence, low levels of PCBs remain detected in wildlife and humans. Although U.S. studies have shown higher serum PCB concentrations among Black women compared with White women, studies of correlates of PCB exposure among Black women are scarce. We examined predictors of plasma PCB concentrations in a cross-sectional analysis of baseline data from a prospective cohort study of 1693 premenopausal Black women aged 23-35 years from Detroit, Michigan (2010-2012). We collected demographic, behavioral, dietary, and medical data via self-administered questionnaires, telephone interviews, and in-person clinic visits, as well as non-fasting blood samples. We measured concentrations of 24 PCB congeners in baseline plasma from a subset of 762 participants. We used linear regression for log-transformed lipid-adjusted PCB concentrations to calculate percentage differences across levels of selected predictors. We did this separately for individual PCBs, sum of total PCBs, and sum of PCBs by degree of chlorination and hormonal activity. PCB concentrations were positively associated with age, duration of urban residence, cigarette smoking, heavy alcohol intake, and being breastfed in infancy, and inversely associated with body mass index (BMI) and lactation duration. The strength of some associations varied by degree of chlorination. For example, a 5-kg/m2 higher BMI corresponded to a 2.9% lower summed concentration of tri- and tetra-substituted PCBs (95% CI -4.6%, -1.2%), an 8.3% lower summed concentration of penta- and hexa-substituted PCBs (95% CI -10.0%, -6.5%), and a 12.1% lower summed concentration of hepta-, octa-, nona-, and deca-substituted PCBs (95% CI -13.7%, -10.4%). Likewise, associations for age and being breastfed in infancy were stronger for higher-chlorinated PCBs. Results agree with studies on predictors of PCB body burdens, few of which include large numbers of Black women. [ABSTRACT FROM AUTHOR]

Background: Uterine leiomyomata (UL) are the leading indication for hysterectomy in the United States. Dietary supplementation with lycopene was associated with reduced size and incidence of oviduct leiomyoma in the Japanese quail. Two US prospective cohort studies of women reported little association between intake of lycopene, or other carotenoids, and UL incidence. However, these studies relied on self-reported physician-diagnosed UL, which is prone to misclassification., Objective: This study examines the association between dietary intake of carotenoids and UL incidence., Design: Data were derived from the Study of the Environment, Lifestyle, and Fibroids, a prospective cohort study. Women completed self-administered baseline questionnaires on demographic characteristics, reproductive history, and lifestyle, including a 110-item validated food frequency questionnaire, from which dietary intakes of carotenoids-including alpha carotene, beta carotene, cryptoxanthin, lutein-zeaxanthin, and lycopene-and vitamin A were estimated., Participants/setting: One thousand two hundred thirty Black women aged 23 to 35 years who did not have a previous diagnosis of UL, cancer, or autoimmune disease were eligible for enrollment (2010-2012). Participants were residents of the Detroit, MI, metropolitan area., Main Outcome Measures: Transvaginal ultrasound was used to assess UL at baseline and 20, 40, and 60 months of follow-up., Statistical Analyses Performed: Cox regression was used to estimate hazard ratios and 95% CIs, adjusted for energy intake, age at menarche, education, body mass index, parity, age at first birth, years since last birth, current use of oral contraceptives or progestin-only injectables, alcohol intake, and cigarette smoking., Results: Among 1,230 women without prevalent UL at baseline, 301 incident UL cases during follow-up were identified. Intakes of lycopene, other carotenoids, and vitamin A were not appreciably associated with UL incidence. Hazard ratios comparing quartiles 2 (2,376 to 3,397 μg/day), 3 (3,398 to 4,817 μg/day), and 4 (≥4,818 μg/day) with quartile 1 (<2,376 μg/day) of lycopene intake were 1.03 (95% CI 0.72 to 1.47), 1.22 (95% CI 0.86 to 1.72), and 0.95 (95% CI 0.67 to 1.36), respectively., Conclusions: Study findings do not support the hypothesis that greater carotenoid intake is associated with reduced UL incidence., (Copyright © 2021 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)