Wu Shaowei, Deng Furong, Huang Jing, Wang Xin, Qin Yu, Zheng Chanjuan, Wei Hongying, Shima Masayuki, Guo Xinbiao
aDepartment of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China bDepartment of Public Health, Hyogo College of Medicine, Hyogo, Japan.
J Hypertens. 2015 Dec;33(12):2414-21. doi: 10.1097/HJH.0000000000000738.
Both low temperature and high air pollution have been associated with an increased risk of cardiovascular events, which could be predicted by increased arterial blood pressure (BP) within short periods. However, whether exposures to temperature and air pollution simultaneously may have interactive effects on BP has been unknown. We investigated this potential interaction during 460 repeated visits in 39 healthy university students in the context of traffic-related air pollution.
Study participants in the Healthy Volunteer Natural Relocation study underwent repeated BP measurements for 12 occasions under three exposure scenarios in Beijing, China, in 2010-2011. We used generalized linear mixed-effects models to estimate exposure effects.
Decreasing temperature was associated with significant increases in BP. There were significant interactions between temperature and traffic-related air pollutants (particulate matter with an aerodynamic diameter ≤2.5 μm, organic carbon, elemental carbon and nitrogen dioxide) on BP (P < 0.05 for all interaction tests). The estimated increases in SBP and DBP were 4.9 mmHg [95% confidence interval (CI) 2.9-6.8] and 3.7 mmHg (95% CI 2.3-5.1) at high elemental carbon level (≥median), and were -1.3 mmHg (95% CI -6.3 to 3.6) and 0.7 mmHg (95% CI -2.8 to 4.2) at low elemental carbon level (<median) per 10°C decrease in daily minimum temperature. We also found stronger air pollution effects on BP at low temperature levels (<median) than at high temperature levels (≥median).
Low temperature and high air pollution may act synergistically to increase BP in healthy adults. Our findings may have potential implications for prevention of cardiovascular events associated with increased BP among high-risk individuals.
低温和高空气污染均与心血管事件风险增加有关，短期内动脉血压（BP）升高可对此进行预测。然而，同时暴露于温度和空气污染是否会对血压产生交互作用尚不清楚。我们在39名健康大学生的460次重复访视中，在与交通相关的空气污染背景下研究了这种潜在的相互作用。
“健康志愿者自然迁移”研究中的参与者于2010 - 2011年在中国北京的三种暴露场景下接受了12次重复血压测量。我们使用广义线性混合效应模型来估计暴露效应。
温度降低与血压显著升高相关。温度与交通相关空气污染物（空气动力学直径≤2.5μm的颗粒物、有机碳、元素碳和二氧化氮）对血压存在显著交互作用（所有交互检验P<0.05）。在元素碳水平高（≥中位数）时，收缩压和舒张压估计升高分别为4.9mmHg [95%置信区间（CI）2.9 - 6.8]和3.7mmHg（95%CI 2.3 - 5.1），而在元素碳水平低（<中位数）时，每日最低温度每降低10°C，收缩压和舒张压估计升高分别为 - 1.3mmHg（95%CI - 6.3至3.6）和0.7mmHg（95%CI - 2.8至4.2）。我们还发现，低温水平（<中位数）下空气污染对血压的影响比高温水平（≥中位数）下更强。
低温和高空气污染可能协同作用增加健康成年人的血压。我们的研究结果可能对预防高危个体中与血压升高相关的心血管事件具有潜在意义。
