广州市孕妇PM_(2.5)暴露对其孕晚期尿和血中白细胞水平的影响

Effects of exposure to PM_(2.5) on urinary leukocyte and white blood cell count of pregnant women in late pregnancy in Guangzhou

目的了解广州市孕妇PM_(2.5)暴露与其孕晚期尿和血中白细胞水平的暴露反应关系,明确其易感暴露窗口。方法根据前期在广州建立的一项出生队列研究(PEOH研究),采用时空土地利用回归模型估算孕妇从怀孕前13周至其孕晚期采样周的每周PM_(2.5)暴露水平。分别使用Cox比例风险模型嵌套的分布滞后非线性模型和分布滞后非线性模型估计孕妇每周PM_(2.5)暴露与其尿白细胞阳性风险和血白细胞计数之间的暴露反应关系。结果本次研究纳入了3753名孕妇。孕妇在第20~27孕周PM_(2.5)暴露与尿白细胞阳性呈正相关,且在第24孕周效应最强,PM_(2.5)每增加10μg/m^(3),HR为1.030(95%CI:1.007~1.054)。孕妇在孕前第5周至第6孕周的PM_(2.5)暴露与血白细胞计数呈正相关,且在末次月经当周效应最强,PM_(2.5)每增加10μg/m^(3),血白细胞计数增加0.22%(95%CI:0.10%~0.35%)。结论孕妇孕期暴露于PM_(2.5)与孕晚期尿白细胞阳性风险升高和血白细胞计数升高有关,易感暴露窗口分别为第20~27孕周和孕前第5周至第6孕周。

Objective To understand the exposure-lag-response associations between exposure to PM_(2.5)and urinary leukocyte and white blood cell count in late pregnancy in Guangzhou,and identify the susceptible exposure windows.Methods According to a birth cohort study on Prenatal Environments and Offspring Health(PEOH)established in Guangzhou in the early stage,a spatiotemporal land-use-regression model was used to estimate a pregnant woman’s weekly PM_(2.5)exposure from 13 weeks before pregnancy to the sampling week in the late pregnancy.A distributed lag non-linear model incorporated with a Cox proportional hazard model was applied to assess the effect of weekly-specific maternal PM_(2.5)exposure on the risk of urinary leukocyte positive,and a distributed lag non-linear model was applied to assess the exposure-lag-response associations between weekly PM_(2.5)exposure and white blood cell count,respectively.Results The sample included 3753 pregnant women.The risk of urinary leukocyte positive was positively associated with maternal PM_(2.5)exposure during the 20 th to 27 th gestational weeks,and the strongest effect was observed in 24 th gestational weeks(HR=1.030,95%CI:1.007-1.054,per 10μg/m^(3) increment in PM_(2.5)).Maternal exposure to PM_(2.5)during the 5 th week before pregnancy to 6 th gestational week was positively associated with white blood cell count,and the strongest effect was observed in 0 gestational week,with a 10μg/m^(3) increment of PM_(2.5),white blood cell count increased 0.22%(95%CI:0.10%-0.35%).Conclusion Maternal exposure to PM_(2.5)may increase the risk of urinary leukocyte positive and increase the white blood cell count in late pregnancy,the 20 th to 27 th gestational week and the 5 th week before pregnancy to 6 th gestational week may be the susceptible exposure windows,respectively.