Chen Fei, Fan Zhiwei, Qiao Zhijiao, Cui Yan, Zhang Meixia, Zhao Xing, Li Xiaosong
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu, 610041, Sichuan Province, China.
Department of Epidemiology and Health Statistics, West China School of Public Health, Sichuan University, Chengdu, 610041, Sichuan Province, China.
Environ Pollut. 2017 May;224:326-335. doi: 10.1016/j.envpol.2017.02.012. Epub 2017 Feb 16.
Large and growing literature has explored whether temperature modified the effect of particular matter (PM) on mortality, but results of the modification effect are inconsistent. In this study, we reviewed information from 29 studies to get the qualitative evidence of the modification effects of temperature on PM to mortality, and the data from 16 of the 29 studies were extracted to conduct a meta-analysis. Temperatures were grouped into three level: "low", "middle" and "high" according to the original studies. The random effect model was used in the meta-analysis with the relative risk (RR) as the measure indicator. The RRs (95% confidence intervals, CIs) for non-accidental death, cardiovascular death and respiratory death per 10 μg/m increase in PM were 1.004 (1.003, 1.006), 1.005 (1.003,1.007), and 1.005 (1.000,1.010) in the low temperature level, 1.005 (1.004,1.006), 1.005 (1.004,1.007), and 1.008 (1.006, 1.010) in the middle temperature level, and 1.012 (1.010, 1.015), 1.016 (1.010, 1.022) and 1.019 (1.010,1.028) in the high temperature level, respectively. In conclusion, moderate evidence exists that temperature modifies the effect of PM on mortality. The effect of PM on respiratory death was the greatest, while the effect on non-accidental death was the smallest in the same temperature level. In addition, the effects of PM on all the three kinds of mortality were the biggest in the high-temperature level, and the smallest in the low-temperature level.
大量且不断增加的文献探讨了温度是否会改变颗粒物（PM）对死亡率的影响，但关于这种改变效应的研究结果并不一致。在本研究中，我们回顾了29项研究的信息，以获取温度对PM致死亡率的改变效应的定性证据，并从这29项研究中的16项提取数据进行荟萃分析。根据原始研究，温度被分为三个水平：“低”、“中”和“高”。荟萃分析采用随机效应模型，以相对风险（RR）作为测量指标。在低温水平下，PM每增加10μg/m³时，非意外死亡、心血管死亡和呼吸死亡的RR（95%置信区间，CI）分别为1.004（1.003，1.006）、1.005（1.003，1.007）和1.005（1.000，1.010）；在中温水平下，分别为1.005（1.004，1.006）、1.005（1.004，1.007）和1.008（1.006，1.010）；在高温水平下，分别为1.012（1.010，1.015）、1.016（1.010，1.022）和1.019（1.010，1.028）。总之，有适度证据表明温度会改变PM对死亡率的影响。在相同温度水平下，PM对呼吸死亡的影响最大，而对非意外死亡的影响最小。此外，PM对所有三种死亡率的影响在高温水平下最大，在低温水平下最小。
