Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan ; School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan.
PLoS One. 2013 Aug 15;8(8):e63320. doi: 10.1371/journal.pone.0063320. eCollection 2013.
The association between ambient air pollution and heart rate variability (HRV) has been well-documented. Little is known about the association of HRV at night with indoor air pollution and coffee consumption. The aim of this study was to investigate the association of HRV indices with indoor air pollution, working time and coffee consumption.
We recruited 60 young healthy convenient store workers to monitor indoor PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5 µm) exposures, coffee consumption (yes vs. no) and HRV indices during daytime (0700-1500 hours) and nighttime (2300-0700 hours). We used linear mixed effects models to assess the associations of HRV indices with indoor PM2.5 exposures and coffee consumption.
We observed the inverse association between indoor PM2.5 exposures and HRV indices, with a decrease in all HRV indices with increased indoor PM2.5 exposures. However, the decrease was most pronounced during nighttime, where a 1 interquartile range (IQR) increase in indoor PM2.5 at 4-hr time-weighted moving average was associated with a change of -4.78% 5-min standard deviation (SD) of normal-to-normal intervals for 5-min segment (SDNN) and -3.23% 5-min square root of the mean squared differences of successive intervals for 5-min segment (r-MSSD). Effects of indoor PM2.5 were lowest for participants with coffee consumption during daytime.
Indoor PM2.5 exposures were associated with decreased 5-min SDNN and 5-min r-MSSD, especially during nighttime. The effect of indoor PM2.5 on HRV indices may be modified by coffee consumption in young healthy convenient store workers.
已有大量文献证实，环境空气污染与心率变异性（HRV）之间存在关联。然而，人们对于夜间 HRV 与室内空气污染、咖啡摄入之间的关联知之甚少。本研究旨在探究 HRV 指标与室内空气污染、工作时间和咖啡摄入之间的关联。
我们招募了 60 名年轻健康的便利店工作人员，在白天（0700-1500 小时）和夜间（2300-0700 小时）监测其室内 PM2.5（空气动力学直径≤2.5μm 的颗粒物）暴露、咖啡摄入（是/否）和 HRV 指标。我们采用线性混合效应模型来评估 HRV 指标与室内 PM2.5 暴露和咖啡摄入的关联。
我们观察到室内 PM2.5 暴露与 HRV 指标呈负相关，随着室内 PM2.5 暴露的增加，所有 HRV 指标均呈下降趋势。然而，这种下降在夜间最为明显，4 小时时间加权移动平均室内 PM2.5 每增加一个四分位距（IQR），5 分钟正常-正常间期标准差（SDNN）降低 4.78%，5 分钟相邻间期均方根差值的平方根（r-MSSD）降低 3.23%。对于白天有咖啡摄入的参与者，室内 PM2.5 的影响最低。
室内 PM2.5 暴露与 5 分钟 SDNN 和 5 分钟 r-MSSD 降低有关，尤其是在夜间。室内 PM2.5 对 HRV 指标的影响可能会被年轻健康便利店工作人员的咖啡摄入所修饰。
