CIBER Epidemiología y Salud Pública, Spain.
Sci Total Environ. 2011 Oct 15;409(22):4667-73. doi: 10.1016/j.scitotenv.2011.08.007. Epub 2011 Sep 1.
Because their lungs and immune system are not completely developed, children are more susceptible to respiratory disease and more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal nitrogen dioxide (NO(2)) levels and the development of lower respiratory tract infections (LRTI), wheezing and persistent cough during the first year of life.
The study population consisted of 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO(2), a marker of traffic related air pollution was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modeled for each residential address through land use regression using the empirical measurements and data from geographic information systems. Postnatal exposure was measured once inside and outside each home using passive samplers for a period of 14 days. Outcomes studied were any episode of LRTI during the child's first year of life diagnosed by a doctor (bronchitis, bronchiolitis or pneumonia), wheezing (defined as whistling sounds coming from the chest), and persistent cough (more than three consecutive weeks). Outcomes and potential confounders were obtained from structured questionnaires. Multiple logistic regression was used to identify associations.
The cumulative incidence (CI) at first year of life was 30.4% for LRTI (23.0% bronchiolitis, 11.9% bronchitis and 1.4% pneumonia), 26.1% for wheezing and 6.3% for persistent cough. The adjusted odds ratio (95% confidence interval) per 10μg/m(3) increment in postnatal outdoor NO(2) concentration was 1.40 (1.02-1.92) for persistent cough. We also found some pattern of association with LRTI, bronchiolitis, bronchitis, wheezing and persistent cough in different prenatal periods, although it was not statistically significant.
Our results indicate that exposure to outdoor, but not indoor, NO(2) during the first year of life increases the risk of persistent cough.
由于儿童的肺部和免疫系统尚未完全发育，他们更容易患呼吸道疾病，并且更容易受到环境污染物的影响。我们评估了产前和产后二氧化氮（NO2）水平与下呼吸道感染（LRTI）、喘息和持续咳嗽在生命的第一年的发展之间的关系。
本研究人群由西班牙巴伦西亚出生队列中的 352 名儿童组成。产前暴露于 NO2，一种交通相关空气污染标志物，在研究区域的 93 个采样点进行了四次为期 7 天的不同采样期的测量。通过使用经验测量值和地理信息系统数据的土地利用回归，为每个住宅地址建立模型。在每个家庭的内部和外部使用被动采样器进行为期 14 天的单次产后暴露测量。研究的结果是在孩子的第一年中由医生诊断的任何下呼吸道感染（支气管炎、细支气管炎或肺炎）、喘息（定义为来自胸部的哨声）和持续咳嗽（超过三个连续星期）。结果和潜在的混杂因素从结构化问卷中获得。使用多变量逻辑回归来识别关联。
在生命的第一年，LRTI 的累积发生率（CI）为 30.4%（细支气管炎 23.0%、支气管炎 11.9%和肺炎 1.4%）、喘息 26.1%和持续咳嗽 6.3%。产后户外 NO2 浓度每增加 10μg/m3，持续咳嗽的调整比值比（95%置信区间）为 1.40（1.02-1.92）。我们还发现了一些与产前不同时期的 LRTI、细支气管炎、支气管炎、喘息和持续咳嗽有关的关联模式，但没有统计学意义。
我们的结果表明，生命的第一年中暴露于户外而非室内的 NO2 会增加持续咳嗽的风险。
