Hypertension:血压升高,空气污染的又一隐患?

2013-02-17 姜莹 整理 中国医学论坛报

    之前已有数项研究评估了空气中污染物对血压水平的短期影响,但其结论存在一定争议,而长期接触空气中污染物质对健康的影响鲜有报告。1月28日,《高血压》(Hypertension)杂志在线发表了一项对中国辽宁省3个城市(包括33个社区人群)的横断面抽样调查结果,评估了空气中污染物含量变化与血压水平及高血压患病率的关系。该研究监测了目标地区3年的PM10(空气动力学直径≤10&nbsp

血压升高,空气污染的又一隐患?
 

  之前已有数项研究评估了空气中污染物对血压水平的短期影响,但其结论存在一定争议,而长期接触空气中污染物质对健康的影响鲜有报告。1月28日,《高血压》(Hypertension)杂志在线发表了一项对中国辽宁省3个城市(包括33个社区人群)的横断面抽样调查结果,评估了空气中污染物含量变化与血压水平及高血压患病率的关系。该研究监测了目标地区3年的PM10(空气动力学直径≤10 μm的颗粒物)、二氧化硫(SO2)、二氧化氮(NO2)和臭氧(O3)的平均浓度,利用广义可加模型和2维逻辑回归模型分析空气污染物对当地居民健康的影响。结果表明,空气污染指数PM10、SO2、O3浓度增加与血压水平升高和高血压患病率有相关性(表),这一相关性只在男性被调查者中具有统计学差异。该研究提示,长期接触空气中污染物可能会导致动脉粥样硬化和其他类型动脉损害,但其机制尚不明确,有待进行更深入的前瞻性研究。

  

  ■专家点评

  空气污染与高血压有关吗?

  中国医学科学院北京阜外心血管病医院 隋辉 王文

  针对长期接触空气中污染物PM10、SO2、O3与收缩压和舒张压升高的相关性,此前各国的研究结果差异很大。有的研究表明,空气污染可导致急性、短暂的血压升高;有的研究结果则显示,短期接触SO2、NO2、O3可使舒张压升高,而接触PM10、SO2、NO2、O3等会降低收缩压;还有研究表明,空气中污染物可升高收缩压、而不升高舒张压等等。对导致这些研究结论不一致的原因尚缺乏全面分析。

  Hypertension杂志最近发表的这项研究结果只在被调查的男性人群中显示出统计学差异,其存在性别差异的原因可能与男性更多地暴露于户外,女性更关注健康、自我防护意识更强等有关。

  一项纳入了4000名生活在美国洛杉矶的黑人妇女的研究表明,住在汽车尾气污染严重地区的妇女们患上糖尿病和高血压的几率更高。而新发表的这项研究并未提供与交通状况有关的空气污染数据,其结果可能会受一些混杂因素的影响。

  2011年发表的《中国高血压防治指南》指出,我国高血压发生的主要危险因素包括高盐饮食、超重/肥胖、过量饮酒和长期精神紧张等。研究空气污染与高血压患病率的关系,可能还须校正已知的高血压危险因素,如年龄、体质指数、超重肥胖等。

  该研究的结果表明,长期接触空气中的污染物PM10、SO2、O3与男性血压水平升高和高血压患病率有相关性,但并不能确定二者有因果关系。空气污染与高血压患病率是否是一种伴随关系尚需进一步的研究。

  目前,空气污染物对人体血压的潜在影响机制缺乏明确阐述,深入研究空气污染对高血压等心血管疾病的作用机制,对改善我国居民健康和促进经济发展都有着十分重要的意义。


Abstract
Several studies have investigated the short-term effects of ambient air pollutants in the development of high blood pressure and hypertension. However, little information exists regarding the health effects of long-term exposure. To investigate the association between residential long-term exposure to air pollution and blood pressure and hypertension, we studied 24 845 Chinese adults in 11 districts of 3 northeastern cities from 2009 to 2010. Three-year average concentration of particles with an aerodynamic diameter ≤10 µm (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and ozone (O3) were calculated from monitoring stations in the 11 districts. We used generalized additive models and 2-level logistic regressions models to examine the health effects. The results showed that the odds ratio for hypertension increased by 1.12 (95% confidence interval [CI], 1.08–1.16) per 19 μg/m3 increase in PM10, 1.11 (95% CI, 1.04–1.18) per 20 μg/m3 increase in SO2, and 1.13 (95% CI, 1.06–1.20) per 22 μg/m3 increase in O3. The estimated increases in mean systolic and diastolic blood pressure were 0.87 mm Hg (95% CI, 0.48–1.27) and 0.32 mm Hg (95% CI, 0.08–0.56) per 19 μg/m3 interquartile increase in PM10, 0.80 mm Hg (95% CI, 0.46–1.14) and 0.31 mm Hg (95% CI, 0.10–0.51) per 20 μg/m3 interquartile increase in SO2, and 0.73 mm Hg (95% CI, 0.35–1.11) and 0.37 mm Hg (95% CI, 0.14–0.61) per 22 μg/m3 interquartile increase in O3. These associations were only statistically significant in men. In conclusion, long-term exposure to PM10, SO2, and O3 was associated with increased arterial blood pressure and hypertension in the study population.

    

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