Abstract:
Long-term mortality effects of particulate air pollution have been investigated in a causal analytic frame, while causal evidence for associations with gaseous air pollutants remains extensively lacking, especially for carbon monoxide (CO) and sulfur dioxide (SO2). In this study, we estimated the causal relationship of long-term exposure to nitrogen dioxide (NO2), CO, SO2, and ozone (O3) with mortality. Utilizing the data from National Morbidity, Mortality, and Air Pollution Study, we applied a variant of difference-in-differences (DID) method with conditional Poisson regression and generalized weighted quantile sum regression (gWQS) to investigate the independent and joint effects. Independent exposures to NO2, CO, and SO2 were causally associated with increased risks of total, nonaccidental, and cardiovascular mortality, while no evident associations with O3 were identified in the entire population. In gWQS analyses, an interquartile range-equivalent increase in mixture exposure was associated with a relative risk of 1.067 (95% confidence interval: 1.010-1.126) for total mortality, 1.067 (1.009-1.128) for nonaccidental mortality, and 1.125 (1.060-1.193) for cardiovascular mortality, where NO2 was identified as the most significant contributor to the overall effect. This nationwide DID analysis provided causal evidence for independent and combined effects of NO2, CO, SO2, and O3 on increased mortality risks among the US general population.
摘要:
已经在因果分析框架中研究了颗粒物空气污染的长期死亡率影响,虽然与气态空气污染物有关的因果证据仍然广泛缺乏,特别是一氧化碳(CO)和二氧化硫(SO2)。在这项研究中,我们估计了长期暴露于二氧化氮(NO2)的因果关系,CO,SO2和臭氧(O3)的死亡率。利用国家发病率的数据,死亡率,空气污染研究,我们应用了具有条件泊松回归和广义加权分位数和回归(gWQS)的差异差异(DID)方法的变体来研究独立效应和联合效应.独立暴露于NO2,CO,和SO2与总风险增加有因果关系,非偶然,和心血管死亡率,虽然在整个人群中没有发现与O3的明显关联。在gWQS分析中,混合物暴露的四分位数间距当量增加与总死亡率1.067(95%置信区间:1.010-1.126)的相对风险相关,1.067(1.009-1.128)非意外死亡率,和1.125(1.060-1.193)的心血管死亡率,其中NO2被确定为总体效应的最重要贡献者。这项全国性的DID分析为NO2、CO、SO2和O3对美国普通人群死亡风险增加的影响。