BACKGROUND Air pollution exposure has been linked to coronary heart disease, although evidence on PM2.5 and myocardial infarction (MI) incidence is mixed. OBJECTIVES This prospective cohort study aimed to investigate associations between long-term exposure to air pollution and MI incidence, adjusting for road traffic noise. METHODS We used data from the nationwide Danish Nurse Cohort on 22,882 female nurses (>44 years of age) who, at recruitment in 1993 or 1999, reported information on cardiovascular disease risk factors. Data on MI incidence was collected from the Danish National Patient Register until the end of 2014. Annual mean concentrations of particulate matter (PM) with a diameter <2.5 μg/m3 (PM2.5), PM10, nitrogen dioxide (NO2), and nitrogen oxides (NOx) at the nurses' residences since 1990 (PM10 and PM2.5) or 1970 (NO2 and NOx) were estimated using the Danish Eulerian Hemispheric Model/Urban Background Model/AirGIS (DEHM/UBM/AirGIS) dispersion model. We used time-varying Cox regression models to examine the association between 1- and 3-y running means of these pollutants, as well as 23-y running means of NO2 and NOx, with both overall and fatal incident MI. Associations were explored in three progressively adjusted models: Model 1, adjusted for age and baseline year; Model 2, with further adjustment for potential confounding by lifestyle and cardiovascular disease risk factors; and Model 3, with further adjustment for road traffic noise, modeled as the annual mean of a weighted 24-h average (Lden). RESULTS Of the 22,882 women, 641 developed MI during a mean follow-up of 18.6 y, 121 (18.9%) of which were fatal. Reported hazard ratios (HRs) were based on interquartile range increases of 5.3, 5.5, 8.1, and 11.5 μg/m3 for PM2.5, PM10, NO2, and NOx, respectively. In Model 1, we observed a positive association between a 3-y running mean of PM2.5 and an overall incident MI with an HR= 1.20 (95% CI: 1.07, 1.35), which attenuated to HR= 1.06 (95% CI: 0.92, 1.23) in Model 2. In Model 1 for incident fatal MI, we observed a strong association with a 3-y running mean of PM2.5, with an HR= 1.69 (95% CI: 1.33, 2.13), which attenuated to HR= 1.35 (95% CI: 1.01, 1.81) in Model 2. Similar associations were seen for PM10, with 3-y, Model 2 estimates for overall and fatal incident MI of HR= 1.06 (95% CI: 0.91, 1.23) and HR= 1.35 (95% CI: 1.01, 1.81), respectively. No evidence of an association was observed for NO2 or NOx. For all pollutants, associations in Model 2 were robust to further adjustment for road traffic noise in Model 3 and were similar for a 1-y running mean exposure. CONCLUSIONS We found no association between long-term exposure to PM2.5, PM10, NO2, or NOx and overall MI incidence, but we observed positive associations for PM2.5 and PM10 with fatal MI. We present novel findings that the association between PM and MI incidence is robust to adjustment for road traffic noise. https://doi.org/10.1289/EHP5818.

中文翻译：

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长期暴露于空气污染和心肌梗塞的发病率：丹麦护士队列研究。

背景技术尽管有关PM2.5和心肌梗塞（MI）发生率的证据不一，但空气污染暴露已与冠心病相关。目的这项前瞻性队列研究旨在调查长期暴露于空气污染与心肌梗塞发生率之间的关联，并针对道路交通噪声进行调整。方法我们使用了来自丹麦全国护士队列的22882名女护士（> 44岁）的数据，这些女护士在1993年或1999年的招聘中报告了有关心血管疾病危险因素的信息。直到2014年底，才从丹麦国家患者登记簿收集关于MI发生率的数据。直径<2.5μg/ m3（PM2.5），PM10，二氧化氮（NO2）和自1990年以来在护士居住的氮氧化物（PMx和PM2。5）或1970年（NO2和NOx）的估算使用的是丹麦欧拉半球模型/城市背景模型/ AirGIS（DEHM / UBM / AirGIS）弥散模型。我们使用随时间变化的Cox回归模型来检查这些污染物的1-y运行方式和3-y运行方式，以及NO2和NOx的23-y运行方式与总体和致命事故MI的关联。在三个逐步调整的模型中探索了关联：模型1，针对年龄和基准年进行了调整；模型2，根据生活方式和心血管疾病危险因素进一步调整了可能的混淆；模型3，进一步调整了道路交通噪音，以24小时加权平均值（Lden）的年平均值为模型。结果在22882名妇女中，有641名在平均随访18.6年后发展为MI，其中121例（18.9％）是致命的。报告的危险比（HRs）基于四分位间距分别对PM2.5，PM10，NO2和NOx增加5.3、5.5、8.1和11.5μg/ m3。在模型1中，我们观察到PM2.5的3年运行平均值与总事件MI之间的正相关关系，HR = 1.20（95％CI：1.07，1.35），衰减到HR = 1.06（95％CI） ：0.92，1.23）在模型2中。在模型1中，对于致命致命MI，我们观察到与PM2.5的3年平均值具有很强的相关性，HR = 1.69（95％CI：1.33，2.13），在模型2中衰减至HR = 1.35（95％CI：1.01，1.81）。对于PM10，也发现了类似的关联，其中模型3对y的总和致命事件MI为HR = 1.06（95％CI：0.91， 1.23）和HR = 1.35（95％CI：1.01，1.81）。没有观察到NO 2或NO x有关联的证据。对于所有污染物，模型2中的关联对于进一步调整模型3中的道路交通噪声具有较强的鲁棒性，并且对于1年平均值的平均暴露情况也相似。结论我们发现长期暴露于PM2.5，PM10，NO2或NOx与总MI发生率之间无关联，但我们观察到PM2.5和PM10与致命MI呈正相关。我们提出了新颖的发现，即PM和MI发生率之间的关联对于调整道路交通噪声具有鲁棒性。https://doi.org/10.1289/EHP5818。我们提出了新颖的发现，即PM和MI发生率之间的关联对于调整道路交通噪声具有鲁棒性。https://doi.org/10.1289/EHP5818。我们提出了新颖的发现，即PM和MI发生率之间的关联对于调整道路交通噪声具有鲁棒性。https://doi.org/10.1289/EHP5818。