Maheswaran Ravi, Pearson Tim, Beevers Sean D, Campbell Michael J, Wolfe Charles D
Public Health GIS Unit, School of Health and Related Research, University of Sheffield, Sheffield, United Kingdom.
Environmental Research Group, King's College London, London, United Kingdom.
PLoS One. 2016 Jun 30;11(6):e0158556. doi: 10.1371/journal.pone.0158556. eCollection 2016.
Few studies have examined the association between air pollutants and ischemic stroke subtypes. We examined acute effects of outdoor air pollutants (PM10, NO2, O3, CO, SO2) on subtypes and severity of incident ischemic stroke and investigated if pre-existing risk factors increased susceptibility.
We used a time stratified case-crossover study and stroke cases from the South London Stroke Register set up to capture all incident cases of first ever stroke occurring amongst residents in a geographically defined area. The Oxford clinical and TOAST etiological classifications were used to classify subtypes. A pragmatic clinical classification system was used to assess severity. Air pollution concentrations from the nearest background air pollution monitoring stations to patients' residential postcode centroids were used. Lags from 0 to 6 days were investigated.
There were 2590 incident cases of ischemic stroke (1995-2006). While there were associations at various lag times with several pollutants, overall, there was no consistent pattern between exposure and risk of ischemic stroke subtypes or severity. The possible exception was the association between NO2 exposure and small vessel disease stroke-adjusted odds ratio of 1.51 (1.12-2.02) associated with an inter-quartile range increase in the lag 0-6 day average for NO2. There were no clear associations in relation to pre-existing risk factors.
Overall, we found little consistent evidence of association between air pollutants and ischemic stroke subtypes and severity. There was however a suggestion that increasing NO2 exposure might be associated with higher risk of stroke caused by cerebrovascular small vessel disease.
很少有研究探讨空气污染物与缺血性卒中亚型之间的关联。我们研究了室外空气污染物（PM10、NO2、O3、CO、SO2）对新发缺血性卒中亚型和严重程度的急性影响，并调查了既往存在的危险因素是否会增加易感性。
我们采用了时间分层病例交叉研究，数据来源于南伦敦卒中登记处，该登记处旨在记录在一个地理区域内居民中首次发生的所有卒中事件。采用牛津临床分类和TOAST病因分类对亚型进行分类。使用实用的临床分类系统评估严重程度。采用距离患者居住邮政编码中心最近的背景空气污染监测站的空气污染浓度数据。研究了0至6天的滞后效应。
共有2590例缺血性卒中事件（1995 - 2006年）。虽然在不同滞后时间与几种污染物存在关联，但总体而言，暴露与缺血性卒中亚型或严重程度风险之间没有一致的模式。可能的例外是NO2暴露与小血管病性卒中之间的关联——调整后的优势比为1.51（1.12 - 2.02），与NO2在滞后0 - 6天的四分位间距增加相关。在既往存在的危险因素方面没有明确的关联。
总体而言，我们几乎没有发现空气污染物与缺血性卒中亚型及严重程度之间存在一致关联的证据。然而，有迹象表明，NO2暴露增加可能与脑血管小血管病导致的卒中风险升高有关。
