von Klot Stephanie, Gryparis Alexandros, Tonne Cathryn, Yanosky Jeffrey, Coull Brent A, Goldberg Robert J, Lessard Darleen, Melly Steven J, Suh Helen H, Schwartz Joel
Department of Environmental Health, Boston, Harvard School of Public Health, Boston, MA, USA.
Epidemiology. 2009 Jul;20(4):547-54. doi: 10.1097/EDE.0b013e31819d9501.
Particulate air pollution has been consistently related to cardiovascular mortality. Some evidence suggests that particulate matter may accelerate the atherosclerotic process. Effects of within-city variations of particulate air pollution on survival after an acute cardiovascular event have been little explored.
We conducted a cohort study of hospital survivors of acute myocardial infarction (MI) from the Worcester, MA, metropolitan area to investigate the long-term effects of within-city variation in traffic-related air pollution on mortality. The study builds on an ongoing community-wide investigation examining changes over time in MI incidence and case-fatality rates. We included confirmed cases of MI in 1995, 1997, 1999, 2001, and 2003. Long-term survival status was ascertained through 2005. A validated spatiotemporal land use regression model for traffic-related air pollution was developed and annual averages of elemental carbon at residence estimated. The effect of estimated elemental carbon on the long-term mortality of patients discharged after MI was analyzed using a Cox proportional hazards model, controlling for a variety of demographic, medical history, and clinical variables.
Of the 3895 patients with validated MI, 44% died during follow-up. Exposure to estimated elemental carbon in the year of entry into the study was 0.44 microg/m on average. All-cause mortality increased by 15% (95% confidence interval = 0.03%-29%) per interquartile range increase in estimated yearly elemental carbon (0.24 microg/m) after the second year of survival. No association between traffic-related pollution and all-cause mortality was observed during the first 2 years of follow-up.
Chronic traffic-related particulate air pollution is associated with increased mortality in hospital survivors of acute MI after the second year of survival.
空气中的颗粒物污染一直与心血管疾病死亡率相关。一些证据表明，颗粒物可能会加速动脉粥样硬化进程。城市内部颗粒物空气污染变化对急性心血管事件后生存率的影响鲜有研究。
我们对马萨诸塞州伍斯特市大都市区急性心肌梗死（MI）住院幸存者进行了一项队列研究，以调查城市内部交通相关空气污染变化对死亡率的长期影响。该研究基于一项正在进行的全社区调查，该调查考察了MI发病率和病死率随时间的变化。我们纳入了1995年、1997年、1999年、2001年和2003年确诊的MI病例。通过2005年确定长期生存状况。开发了一个经过验证的交通相关空气污染时空土地利用回归模型，并估计了居住地元素碳的年平均值。使用Cox比例风险模型分析估计的元素碳对MI后出院患者长期死亡率的影响，并控制各种人口统计学、病史和临床变量。
在3895例确诊MI的患者中，44%在随访期间死亡。进入研究年份时估计的元素碳暴露平均为0.44微克/立方米。生存第二年之后，估计的年度元素碳每增加一个四分位间距（0.24微克/立方米），全因死亡率增加15%（95%置信区间=0.03%-29%）。在随访的前两年未观察到交通相关污染与全因死亡率之间的关联。
慢性交通相关颗粒物空气污染与急性MI住院幸存者生存第二年之后的死亡率增加有关。
