云南宣威农村妇女孕期PM2.5暴露与妊娠结局及儿童糖脂代谢的队列研究

Air pollution may have significant impact on pregnancy and birth outcomes, as well as on risk of metabolic disorders such as obesity. This study proposes to follow pregnant women and their newborn children to examine how fetal exposure to air particulate matter less than 2.5 microns (PM2.5) influences birth outcomes and risk of obesity and metabolic disorders in the offspring. Conducted in Xuanwei, which has the highest level of indoor air pollution in the country and one of the highest rates of lung cancer mortality, this study is to examine the role of air pollution in obesity development. Using a sampling design that will select 20 areas of Xuanwei with varying levels of outdoor air pollution, this study will recruit 600 pregnant women during their first trimester and follow them through each trimester. The air quality to which women are exposed will be measured using a portable PM2.5 air quality monitor worn by each woman for a week at a time. Diet and exposure to tobacco smoke, potential confounders, will be assessed from 24-hour diet recalls and urinary cotinine. In addition, a questionnaire will be developed to gather additional diet and tobacco exposure data as well as data on other confounders including physical activity, socioeconomic status, and pregnancy complications. The outcome varibles of interest - fetal growth; birth weight, height and head circumference; and newborn development and metabolic indicators in umbilical cord blood (insulin, glucose, lipids, leptin and adiponectin) - will be measured using standardized protocols. Using appropriate statistial techniques, a growth mixture model will be constructed to estimate the independent effects of PM2.5 exposure and secondhand smoke. Findings will be used to develop a prospective cohort study to investigate the contribution of air pollution to obesity and other metabolic disorders. The goal is to improve child health and reduce risk of chronic metabolic disorders by addressing environmental pollutants in rapidly changing China.

随着全球环境污染问题日益加剧，环境污染与不良妊娠结局的相关性成为环境与健康领域的关注焦点。云南宣威农村室内空气污染严重，妇女肺癌死亡率高。本研究应用队列研究，在宣威农村建立孕期PM2.5暴露出生队列，以早期确诊怀孕为队列起点，采用可移动的、能随身携带的小型空气质量监测仪测量妇女孕早、中、晚期PM2.5个体暴露水平，检测二手烟暴露量，监测孕妇孕中、晚期营养素摄入状况；观察不良妊娠结局发生情况，检测脐血中血糖、胰岛素、血脂、脂联素和瘦素等糖脂代谢相关指标。运用mplus软件进行增长混合模型分析，分别探讨不同孕期PM2.5暴露累积、二手烟暴露与不良妊娠结局的关系以及对早期儿童糖脂代谢的影响。同时运用MlwiN或SAS软件进行多水平模型分析以上结果的影响因素。研究结果可为宣威及同类地区环境保护政策的制定、不良妊娠结局的预防工作提供科学依据。所建立的队列为进一步研究儿童早期暴露与健康的关系奠定基础。

针对全球环境污染对健康影响的热点问题，聚焦妇女孕期全程PM2.5暴露对妊娠结局、子代早期糖脂代谢稳态的影响，在云南农村地区建立出生队列。招募孕早期妇女674人，至分娩时母亲婴儿共645对。PM2.5暴露检测666例孕妇，检测589例妇女尿样可替宁和尼古丁。结果显示孕妇PM2.5暴露日平均值孕早、中期均为28.5μg/m3，孕晚期为28.1μg/m3，个体瞬时最大值1072μg/m3，冬季明显高于其他季节，日间两次高峰与烹饪时间吻合；燃煤取暖、打扫房间、冬季、孕妇受教育程度低和二手烟暴露增加了孕期PM2.5暴露的风险。尿可替宁总检出率为92.17%，孕早中晚期平均水平分别为4.33 ng/mL、4.13 ng/mL和3.87 ng/mL。活产651例，胎龄39.06±1.82，出生体重3160.46±407.06g，身长50.24±1.61cm，头围33.96±1.76cm,发生不良妊娠结局59例。.新生儿脐血11项指标除瘦素、脂联素、总胆固醇和甘油三酯处于较低水平外，胰岛素等其他指标与国内外报道值相近。孕晚期PM2.5高暴露组瘦素水平低于低暴露组。.多元线性回归分析孕早、中、晚期PM2.5、可替宁暴露以及胎儿性别、孕周、孕期增重和大豆及制品对妊娠结局和脐带血糖脂代谢指标的独立作用，未发现孕早中晚三期PM2.5对出生体重有影响，但是孕早、晚期PM2.5高暴露与头围呈负相关，尤以早期暴露影响显著；孕早期可替宁可影响胎儿头围发育，孕晚期PM2.5暴露水平越高，瘦素和脂联素水平越低。.拟合潜变量混合增长曲线模型分析发现孕早期暴露于高浓度的PM2.5中，对胰岛素水平有影响，孕早、中期PM2.5高暴露降低胰岛素样生长因子水平，孕晚期PM2.5高暴露会显著降低瘦素的水平，孕中期和孕晚期PM2.5暴露可影响脂联素水平。不同的暴露类别下的婴儿体重、头围和血糖差异无统计学意义。.综上，云南农村妇女孕期PM2.5暴露呈普遍低水平，兼瞬时高暴露特点，受季节、烹饪等家务劳动及生活习惯等因素的影响；二手烟暴露普遍，总体高于国内其他报道；不同孕期PM2.5、二手烟暴露以及累计暴露对妊娠结局和糖脂代谢有一定影响，但影响趋势不显著。妇女自孕早期起避免或减少PM2.5、二手烟暴露对于早期儿童健康，乃至儿童长期的健康都具有重要的意义。