Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan; Division of Surgical Intensive Care, Department of Critical Care Medicine, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan.
Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan.
Environ Res. 2014 May;131:1-5. doi: 10.1016/j.envres.2014.01.009. Epub 2014 Mar 4.
Particulate matter with aerodynamic diameter of <2.5 μm (PM2.5) is associated with blood pressure and hemodynamic changes. Blunted nocturnal blood pressure dipping is a major risk factor for cardiovascular events; limited information is available on whether PM2.5 exposure-related hemodynamic changes vary with day-night blood pressure circadian rhythms. In this study, we enrolled 161 subjects and monitored the changes in ambulatory blood pressure and hemodynamics for 24h. The day-night blood pressure and cardiovascular metrics were calculated according to the sleep-wake cycles logged in the subject׳s diary. The effects of PM2.5 exposure on blood pressure and hemodynamic changes were analyzed using generalized linear mixed-effect model. After adjusting for potential confounders, a 10-μg/m(3) increase in PM2.5 was associated with 1.0 mmHg [95% confidence interval (CI): 0.2-1.8 mmHg] narrowing in the pulse pressure, 3.1% (95% CI: 1.4-4.8%) decrease in the maximum rate of left ventricular pressure rise, and 3.6% (95% CI: 1.6-5.7%) increase in systemic vascular resistance among 79 subjects with nocturnal blood pressure dip of <10%. In contrast, PM2.5 was not associated with any changes in cardiovascular metrics among 82 subjects with nocturnal blood pressure dip of ≥10%. Our findings demonstrate that short-term exposure to PM2.5 contributes to pulse pressure narrowing along with cardiac and vasomotor dysfunctions in subjects with nocturnal blood pressure dip of <10%.
粒径小于 2.5μm 的颗粒物（PM2.5）与血压和血液动力学变化有关。夜间血压下降幅度变平是心血管事件的主要危险因素；目前关于 PM2.5 暴露相关的血液动力学变化是否随昼夜血压的节律变化而变化的信息有限。在这项研究中，我们纳入了 161 名受试者，并监测了 24 小时的动态血压和血液动力学变化。根据受试者日记中记录的睡眠-觉醒周期计算出昼夜血压和心血管指标。使用广义线性混合效应模型分析 PM2.5 暴露对血压和血液动力学变化的影响。在调整了潜在的混杂因素后，PM2.5 浓度每增加 10μg/m3，与 79 名夜间血压下降<10%的受试者的脉压下降 1.0mmHg（95%可信区间：0.2-1.8mmHg）、左心室压力上升最大速率下降 3.1%（95%可信区间：1.4-4.8%）和全身血管阻力增加 3.6%（95%可信区间：1.6-5.7%）有关。相比之下，在夜间血压下降≥10%的 82 名受试者中，PM2.5 与心血管指标的任何变化均无关。我们的研究结果表明，短期 PM2.5 暴露可导致夜间血压下降幅度<10%的受试者的脉压变窄以及心脏和血管舒缩功能障碍。
