1 The Jockey Club School of Public Health and Primary Care, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin-NT, Hong Kong Special Administrative Region, China.
Am J Respir Crit Care Med. 2013 Nov 15;188(10):1240-5. doi: 10.1164/rccm.201304-0676OC.
Recent experimental and clinical studies suggest that exogenous carbon monoxide (CO) at lower concentrations may have beneficial effects under certain circumstances, whereas population-based epidemiologic studies of environmentally relevant CO exposure generated mixed findings.
To examine the acute effects of ambient CO on respiratory tract infection (RTI) hospitalizations.
A time series study was conducted. Daily emergency hospital admission and air pollution data in Hong Kong were collected from January 2001 to December 2007. Log-linear Poisson models were used to estimate the associations between daily hospital admissions for RTI and daily average concentrations of CO across three background air monitoring stations and three roadside stations, respectively, controlling for other traffic-related copollutants.
CO concentrations were low during the study period with a daily average of 0.6 ppm in background stations and 1.0 ppm in roadside stations. Negative associations were found between ambient CO concentrations and daily hospital admissions for RTI. One ppm increase in background CO at lag 0-2 days was associated with -5.7% (95% confidence interval, -9.2 to -2.1) change in RTI admissions from the whole population according to single-pollutant model; the negative association became stronger when nitrogen dioxide or particulate matter with aerodynamic diameter less than 10 μm was adjusted for in two-pollutant models. The negative association seemed to be stronger in the adults than in the children and elderly.
Short-term exposure to ambient CO was associated with decreased risk of hospital admissions for RTI, suggesting some acute protective effects of low ambient CO exposure on respiratory infection.
最近的实验和临床研究表明，在某些情况下，较低浓度的外源性一氧化碳（CO）可能具有有益的影响，而基于人群的与环境相关的 CO 暴露的流行病学研究得出了混合的结果。
研究环境 CO 对呼吸道感染（RTI）住院的急性影响。
进行了一项时间序列研究。从 2001 年 1 月至 2007 年 12 月，收集了香港每日急诊住院和空气污染数据。对数线性泊松模型用于估计每日 RTI 住院与三个背景空气监测站和三个路边站的 CO 日平均浓度之间的关联，分别控制其他交通相关的共污染物。
在研究期间，CO 浓度较低，背景站的日平均浓度为 0.6ppm，路边站的日平均浓度为 1.0ppm。环境 CO 浓度与 RTI 每日住院人数之间存在负相关。单污染物模型显示，滞后 0-2 天背景 CO 增加 1ppm，与总人口 RTI 入院率降低 5.7%（95%置信区间，-9.2 至-2.1）有关；当调整两种污染物模型中的二氧化氮或空气动力学直径小于 10μm 的颗粒物时，负相关变得更强。在成年人中，这种负相关似乎比儿童和老年人更强。
短期暴露于环境 CO 与 RTI 住院风险降低相关，表明低环境 CO 暴露对呼吸道感染具有一定的急性保护作用。
