McGill University, Montreal, QC, Canada; CHU Sainte-Justine Research Centre, Université de Montréal, Montreal, QC, Canada.
Dalhousie University, Halifax, NS, Canada.
Environ Res. 2016 May;147:71-81. doi: 10.1016/j.envres.2016.01.040. Epub 2016 Feb 5.
Studies report increases in rates of gestational diabetes mellitus (GDM) over recent decades. Environmental chemicals may increase the risk of diabetes through impacts on glucose metabolism, mitochondrial dysfunction, and endocrine-disrupting mechanisms including effects on pancreatic β-cell function and adiponectin release.
To determine the associations between pesticides, perfluoroalkyl substances (PFASs) and polychlorinated biphenyls (PCBs) measured in early pregnancy and impaired glucose tolerance (IGT) and GDM in a Canadian birth cohort.
Women enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study were included if they had a singleton delivery and did not have pre-existing diabetes. Exposure variables included three organophosphorus (OP) pesticide metabolites detected in first-trimester urine samples, as well as three organochlorine (OC) pesticides, three PFASs, and four PCBs in first-trimester blood samples. Gestational IGT and GDM were assessed by chart review in accordance with published guidelines. Adjusted logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI) for the association between quartiles of environmental chemicals and both gestational IGT and GDM.
Of the 2001 women recruited into the MIREC cohort, 1274 met the inclusion criteria and had outcome and biomonitoring data available. Significantly lower odds of GDM were observed in the third and fourth quartiles of dimethylphosphate (DMP) and in the fourth quartile of dimethylthiophosphate (DMTP) in adjusted analyses (DMP Q3: OR=0.2, 95% CI=0.1-0.7; DMP Q4: OR=0.3, 95% CI=0.1-0.8; DMTP: OR=0.3, 95% CI=0.1-0.9). Significantly elevated odds of gestational IGT was observed in the second quartile of perfluorohexane sulfonate (PFHxS) (OR=3.5, 95% CI=1.4-8.9). No evidence of associations with GDM or IGT during pregnancy was observed for PCBs or OC pesticides.
We did not find consistent evidence for any positive associations between the chemicals we examined and GDM or IGT during pregnancy. We observed statistical evidence of inverse relationships between urine concentrations of DMP and DMTP with GDM. We cannot rule out the influence of residual confounding due to unmeasured protective factors, such as nutritional benefits from fruit and vegetable consumption, also associated with pesticide exposure, on the observed inverse associations between maternal OP pesticide metabolites and GDM. These findings require further investigation.
研究报告显示，近年来妊娠糖尿病（GDM）的发病率有所上升。环境化学物质可能通过影响葡萄糖代谢、线粒体功能以及包括对胰腺β细胞功能和脂联素释放影响在内的内分泌干扰机制，增加患糖尿病的风险。
在加拿大出生队列中，确定妊娠早期测量的农药、全氟烷基物质（PFAS）和多氯联苯（PCBs）与葡萄糖耐量受损（IGT）和 GDM 之间的关联。
如果女性有单胎分娩且没有糖尿病前期，且参加了母婴环境化学物质研究（MIREC），则将其纳入研究。暴露变量包括在孕早期尿液样本中检测到的三种有机磷（OP）农药代谢物，以及在孕早期血液样本中检测到的三种有机氯（OC）农药、三种 PFAS、四种 PCB。根据已发表的指南，通过图表审查评估妊娠期间 IGT 和 GDM。使用调整后的逻辑回归模型计算环境化学物质四分位间距与妊娠期间 IGT 和 GDM 之间关联的比值比（OR）和 95%置信区间（CI）。
在 MIREC 队列中招募的 2001 名女性中，有 1274 名符合纳入标准，且有结局和生物监测数据可用。在调整分析中，DMP 和 DMTP 的第三和第四四分位数与 GDM 的发生呈负相关（DMP Q3：OR=0.2，95%CI=0.1-0.7；DMP Q4：OR=0.3，95%CI=0.1-0.8；DMTP：OR=0.3，95%CI=0.1-0.9）。PFHxS 的第二四分位数与妊娠 IGT 的发生呈正相关（OR=3.5，95%CI=1.4-8.9）。我们没有发现研究的化学物质与妊娠期间 GDM 或 IGT 之间存在任何阳性关联的一致证据。我们观察到 DMP 和 DMTP 尿液浓度与 GDM 之间存在统计学上的负相关。我们不能排除由于未测量的保护因素（如与农药暴露相关的水果和蔬菜消费带来的营养益处）引起的剩余混杂因素的影响，这些因素也与观察到的母体 OP 农药代谢物与 GDM 之间的负相关有关。这些发现需要进一步调查。
