O'Lenick Cassandra R, Winquist Andrea, Mulholland James A, Friberg Mariel D, Chang Howard H, Kramer Michael R, Darrow Lyndsey A, Sarnat Stefanie Ebelt
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA.
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA.
J Epidemiol Community Health. 2017 Feb;71(2):129-136. doi: 10.1136/jech-2015-206530. Epub 2016 Jul 15.
A broad literature base provides evidence of association between air pollution and paediatric asthma. Socioeconomic status (SES) may modify these associations; however, previous studies have found inconsistent evidence regarding the role of SES.
Effect modification of air pollution-paediatric asthma morbidity by multiple indicators of neighbourhood SES was examined in Atlanta, Georgia. Emergency department (ED) visit data were obtained for 5-18 years old with a diagnosis of asthma in 20-county Atlanta during 2002-2008. Daily ZIP Code Tabulation Area (ZCTA)-level concentrations of ozone, nitrogen dioxide, fine particulate matter and elemental carbon were estimated using ambient monitoring data and emissions-based chemical transport model simulations. Pollutant-asthma associations were estimated using a case-crossover approach, controlling for temporal trends and meteorology. Effect modification by ZCTA-level (neighbourhood) SES was examined via stratification.
We observed stronger air pollution-paediatric asthma associations in 'deprivation areas' (eg, ≥20% of the ZCTA population living in poverty) compared with 'non-deprivation areas'. When stratifying analyses by quartiles of neighbourhood SES, ORs indicated stronger associations in the highest and lowest SES quartiles and weaker associations among the middle quartiles.
Our results suggest that neighbourhood-level SES is a factor contributing vulnerability to air pollution-related paediatric asthma morbidity in Atlanta. Children living in low SES environments appear to be especially vulnerable given positive ORs and high underlying asthma ED rates. Inconsistent findings of effect modification among previous studies may be partially explained by choice of SES stratification criteria, and the use of multiplicative models combined with differing baseline risk across SES populations.
大量文献表明空气污染与儿童哮喘之间存在关联。社会经济地位（SES）可能会改变这些关联；然而，先前的研究在SES的作用方面发现了不一致的证据。
在佐治亚州亚特兰大市，研究了邻里SES的多个指标对空气污染与儿童哮喘发病率之间关联的效应修正。获取了2002 - 2008年期间亚特兰大20个县5 - 18岁诊断为哮喘的急诊室（ED）就诊数据。利用环境监测数据和基于排放的化学传输模型模拟，估算了每日邮政编码分区（ZCTA）层面的臭氧、二氧化氮、细颗粒物和元素碳浓度。采用病例交叉法估算污染物与哮喘的关联，并控制时间趋势和气象因素。通过分层研究ZCTA层面（邻里）SES的效应修正。
与“非贫困地区”相比，我们在“贫困地区”（例如，ZCTA人口中≥20%生活在贫困中）观察到更强的空气污染与儿童哮喘的关联。当按邻里SES四分位数分层分析时，比值比（OR）表明在最高和最低SES四分位数中关联更强，而在中间四分位数中关联较弱。
我们的结果表明，邻里层面的SES是导致亚特兰大儿童易患与空气污染相关哮喘发病率的一个因素。鉴于正的OR值和较高的潜在哮喘急诊率，生活在低SES环境中的儿童似乎尤其易受影响。先前研究中效应修正结果不一致可能部分归因于SES分层标准的选择，以及乘法模型的使用与不同SES人群基线风险的差异。
