Nicholas School of the Environment, Duke University, Durham, NC 27705, USA.
Department of Respiratory Medicine, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China.
Environ Int. 2018 May;114:27-36. doi: 10.1016/j.envint.2018.02.010. Epub 2018 Feb 22.
More than 90% of the world's population lives in areas where outdoor air pollution levels exceed health-based limits. In these areas, individuals may use indoor air filtration, often on a sporadic basis, in their residences to reduce exposure to respirable particles (PM). Whether this intervention can lead to improvements in health outcomes has not been evaluated.
Seventy non-smoking healthy adults, aged 19 to 26 years, received both true and sham indoor air filtration in a double-blinded randomized crossover study. Each filtration session was approximately 13 h long. True and sham filtration sessions were separated by a two-week washout interval. The study was carried out in a suburb of Shanghai.
During the study period, outdoor PM concentrations ranged from 18.6 to 106.9 μg/m, which overlapped with levels measured in Western Europe and North America. Compared to sham filtration, true filtration on average decreased indoor PM concentration by 72.4% to 10.0 μg/m and particle number concentration by 59.2% to 2316/cm. For lung function measured immediately after the end of filtration, true filtration significantly lowered airway impedance at 5 Hz (Z) by 7.1% [95% CI: 2.4%, 11.9%], airway resistance at 5 Hz (R) by 7.4% [95% CI: 2.4%, 12.5%], and small airway resistance (R-R) by 20.3% [95% CI: 0.1%, 40.5%], reflecting improved airway mechanics especially for the small airways. However, no significant improvements for spirometry indicators (FEV, FVC) were observed. True filtration also significantly lowered von Willebrand factor (VWF) by 26.9% [95% CI: 7.3%, 46.4%] 24 h after the end of filtration, indicating reduced risk for thrombosis. Stratified analysis in male and female participants showed that true filtration significantly decreased pulse pressure by 3.3% [95% CI: 0.8%, 7.4%] in females, and significantly reduced VWF by 42.4% [95% CI: 17.4%, 67.4%] and interleukin-6 by 22.6% [95% CI: 0.4%, 44.9%] in males. Effect modification analyses indicated that filtration effects in male and female participants were not significantly different.
A single overnight residential air filtration, capable of reducing indoor particle concentrations substantially, can lead to improved airway mechanics and reduced thrombosis risk.
世界上超过 90%的人口生活在室外空气污染水平超过健康基准的地区。在这些地区，人们可能会在居住的地方使用室内空气过滤设备，通常是间歇性的，以减少可吸入颗粒物（PM）的暴露。然而，这种干预是否能改善健康结果尚未得到评估。
70 名年龄在 19 至 26 岁之间的不吸烟健康成年人在一项双盲随机交叉研究中接受了真实和假的室内空气过滤。每个过滤时段约为 13 小时。真实和假的过滤时段之间间隔两周的洗脱期。研究在上海郊区进行。
在研究期间，室外 PM 浓度范围为 18.6 至 106.9μg/m，与西欧和北美测量到的水平重叠。与假过滤相比，真实过滤平均将室内 PM 浓度降低了 72.4%至 10.0μg/m，将颗粒数浓度降低了 59.2%至 2316/cm。对于过滤结束后立即测量的肺功能，真实过滤显著降低了气道阻抗在 5Hz（Z）下的 7.1%[95%置信区间：2.4%，11.9%]，气道阻力在 5Hz（R）下的 7.4%[95%置信区间：2.4%，12.5%]，以及小气道阻力（R-R）下的 20.3%[95%置信区间：0.1%，40.5%]，反映了气道力学的改善，特别是小气道。然而，对于肺活量指标（FEV、FVC）并没有观察到显著的改善。真实过滤还使 von Willebrand 因子（VWF）在过滤结束后 24 小时降低了 26.9%[95%置信区间：7.3%，46.4%]，表明血栓形成的风险降低。在男性和女性参与者的分层分析中，真实过滤显著降低了女性的脉搏压 3.3%[95%置信区间：0.8%，7.4%]，显著降低了男性的 VWF 42.4%[95%置信区间：17.4%，67.4%]和白细胞介素-6 22.6%[95%置信区间：0.4%，44.9%]。效应修饰分析表明，男性和女性参与者的过滤效果没有显著差异。
单次夜间住宅空气过滤，能够显著降低室内颗粒物浓度，可改善气道力学并降低血栓形成风险。
