Early Pregnancy Metal(loid) Mixtures and Second Trimester Glucose Levels
Year: 2019
Type: conference-abstract
Abstract: OPS 41: Metals and birth outcomes, Room 411, Floor 4, August 26, 2019, 4:30 PM - 5:30 PM Background/Aim: Previous studies suggested that a number of essential metal(loid)s are required in normal glucose metabolism, while certain non-essential metal(loid)s are associated with risk of diabetes. However, the effects of these metal(loids)s on glycemia during pregnancy, either individually or jointly, are unclear. We aimed to explore associations of early pregnancy essential (chromium, copper, magnesium, manganese, selenium, vanadium, zinc) and non-essential (arsenic, barium, cadmium, cesium, mercury, lead) metal(loid)s, individually and as a mixture, with second trimester glucose levels. Methods: We studied 1382 pregnant women enrolled in Project Viva, a prospective pre-birth cohort in eastern Massachusetts. Red blood cell (RBC) concentrations of metal(loid)s were quantified in early pregnancy blood samples (median: 10 weeks gestation) using Direct Mercury Analyzer 80 (for mercury) and Inductively Coupled Plasma Mass Spectrometry (for all others). Glucose levels were abstracted from the 50-gram, non-fasting glucose challenge test for screening gestational diabetes (median: 28 weeks gestation). We conducted linear regression analyses with all metal(loid)s mutually adjusted in addition to other confounders. Bayesian Kernel Machine Regression (BKMR) was then applied to flexibly model the dose-response relationships between the metal(loid) mixtures and glucose levels and qualitatively investigate interactions. Results: In adjusted linear regression analyses, 1 standard deviation higher ln-transformed mercury was associated with 2.0 mg/dL lower glucose levels (95% confidence interval: -3.7, -0.2). The individual associations of metal(loid)s were consistent in BKMR accounting for joint effects, with smaller estimated effect sizes and greater variations. Bivariate analyses in BKMR suggested sub-additive interactions between chromium and barium, and between chromium and selenium. Conclusions: We found suggestive evidences that early pregnancy higher mercury was associated with lower glucose levels. The potential hyperglycemic effect of chromium may be dependent on barium and selenium concentrations. Future work is needed to better understand the joint effects of these metal(loid)s in the context of glucose regulation in pregnancy.
Source: Environmental Epidemiology
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,200
OpenAlex ID: W2981337573