Objective: To assess the associations of indoor fine particulate matter (PM(2.5)) from outdoor and indoor sources with heart rate (HR) and heart rate variability (HRV) in patients with chronic obstructive pulmonary disease (COPD) of Beijing. Methods: A total of 40 male patients in a stable stage of COPD were recruited from a hospital in a panel study in Beijing with 5 consecutive days of measurement for each subject. General information and disease history of the participants from questionnaires were obtained prior to the study. HR and HRV were repeatedly examined using dynamic electrocardiograph. HRV included standard deviation of all NN intervals (SDNN), root mean square of successive differences between adjacent NN intervals (rMSSD), total power (TP) power in the low-frequency band (LF) and the high-frequency band (HF). Iron was used as tracer element to separate indoor-originated PM(2.5) and outdoor-originated PM(2.5). Mixed-effect models were applied to assess the associations of outdoor-originated PM(2.5) or indoor-originated PM(2.5) and health effects. Results: The P(50) (P(25), P(75)) values of daily indoor PM(2.5), indoor-originated PM(2.5) and outdoor-originated PM(2.5) were 50.9 (26.8, 122.7), 16.0 (1.9, 43.7) and 27.3 (13.5, 61.8) μg/m(3), respectively. The mean±SD of concentrations of real-time indoor PM(2.5), indoor-originated PM(2.5) and outdoor-originated PM(2).5 were (61.5±58.8), (25.3±39.1) and (36.2±42.7) μg/m(3), respectively. Compared with outdoor-originated PM(2.5), indoor-originated PM(2.5) had significant associations with HRV and HR. Each 10 μg/m(3) increase at 4 h indoor-originated PM(2.5) and outdoor-originated PM(2.5) moving average was associated with 3.4% (95%CI: -4.7%, -2.1%) and 0.6% (95%CI: -2.0%, -0.8%) reduction in TP (P<0.001). Each 10 μg/m(3) increase at 12 h indoor-originated PM(2.5) moving average was associated with 7.6% (95%CI: -10.1%, -5.1%), 4.7% (95%CI: -6.7%, -2.7%), 3.3% (95%CI: -4.2%,-2.4%) and 3.0% (95%CI: -4.5%, -1.5%) reduction in HF, LF, SDNN and rMSSD, respectively. Each 10 μg/m(3) increase at 12 h outdoor-originated PM(2.5) moving average was associated with 0.7% (95%CI: -2.7%, -1.4%), 0.2% (95%CI: -1.9%, 1.4%), 0.7% (95%CI: -1.4%, -0.1%) and 0.2% (95%CI: -1.3%, 0.9%) reduction in HF, LF, SDNN and rMSSD, respectively (P<0.001). Each 10 μg/m(3) increase at 8 h indoor-originated PM(2.5) and outdoor-originated PM(2.5) moving average was associated with 0.7% (95%CI: 0.4%, 1.0%) and 0.4% (95%CI: 0.2%, 0.6%) increase in HR. Conclusion: Exposure to indoor-originated PM(2.5) was more strongly associations with HRV indices and HR compared with outdoor-originated PM(2.5) in male COPD patients.
目的： 评价北京住宅中室内外来源PM(2.5)对慢性阻塞性肺疾病（COPD）患者心率及心率变异性（HRV）指标的影响。 方法： 于2015年11月至2016年5月，采用定组研究设计，于北京某三甲医院呼吸科招募40例稳定期男性COPD患者，每例患者的研究时间跨度均为连续的5 d。通过自行设计问卷调查其一般情况及疾病史等信息，并对其心率和HRV指标进行动态心电图监测（仅于第3天进行实时监测），HRV包括所有窦性心搏R-R间期的标准差（SDNN）、全程相邻窦性心搏R-R间期之差的均方根（rMSSD）、总功率、低频功率及高频功率。测量每天室内外PM(2.5)暴露浓度；以Fe作为示踪元素，通过测定PM(2.5)样品中Fe元素含量，以拆分室内外来源PM(2.5)暴露浓度。采用混合效应模型分别分析室内外来源PM(2.5)暴露对COPD患者心率及HRV的短期影响。 结果： 住宅中日均PM(2.5)暴露浓度的P(50)（P(25)，P(75)）为50.9（26.8，122.7）μg/m(3)，室内外来源的PM(2.5)暴露浓度分别为16.0（1.9，43.7）和27.3（13.5，61.8）μg/m(3)。实时监测中，住宅中总PM(2.5)暴露浓度为（61.5±58.8）μg/m(3)，其中室内外来源分别为（25.3±39.1）和（36.2±42.7）μg/m(3)。室内来源PM(2.5)暴露浓度每升高10 μg/m(3)使研究对象HRV降低水平高于室外来源，主要表现为：累积滞后4 h时，室内外来源PM(2.5)暴露浓度每升高10 μg/m(3)导致总频率的变化率及95%CI值分别为-3.4%（-4.7%，-2.1%）和-0.6%（-2.0%，-0.8%）（P<0.001）；室内来源PM(2.5)暴露浓度在累积滞后12 h时所对应的高频功率、低频功率、SDNN及rMSSD的变化率及95%CI值分别为-7.6%（-10.1%，-5.1%）、-4.7%（-6.7%，-2.7%）、-3.3%（-4.2%，-2.4%）及-3.0%（-4.5%，-1.5%），室外来源分别为-0.7%（-2.7%，-1.4%）、-0.2%（-1.9%，1.4%）、-0.7%（-1.4%，-0.1%）及-0.2%（-1.3%，0.9%）（P<0.001）。室内来源PM(2.5)暴露浓度每升高10 μg/m(3)导致心率增加程度高于室外来源，主要表现为：滞后8 h时，室内外来源PM(2.5)暴露浓度每升高10 μg/m(3)分别导致心率增加0.7%（95%CI：0.4%，1.0%）和0.4%（95%CI：0.2%，0.6%）（P<0.001）。 结论： 与室外来源相比，室内来源的PM(2.5)暴露对COPD患者心率及HRV的影响更为明显。.
Keywords: Air pollution, indoor; Heart rate variability; Particulate matter; Pulmonary disease, chronic obstructive.