Time-series analysis of the relationship between air quality, temperature, and sudden unexplained death in Beijing during 2005 - 2008 / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There is a yearly increase in the rate of sudden unexplained death (SUD), even through extensive physical examination and the testing of a large number of biomarkers, the cause of sudden death in patients previously in good health cannot be fully determined. During clinical practice, a spatial aggregation phenomenon has been observed in the incidence of sudden unexplained death. Previous research has shown that environmental factors, such as air pollution, weather conditions, etc., have a significant impact on human health. In the wake of the continuous environmental damage, the relationship between environmental factors and sudden unexplained death still needs to be studied. To study the relationship between sudden unexplained death and air quality and temperature, commonly used markers such as particulate matter of aerodynamic diameter < 10 µm (PM(10)), daily average concentration of the gaseous pollutants sulfur dioxide (SO2) and nitrogen dioxide (NO2), and the daily average temperature were investigated.</p><p><b>METHODS</b>The methods include collecting the data of sudden unexplained death; air quality monitoring; meteorological monitoring from January 1, 2005 to December 31, 2008; utilizing generalized additive models (GAM); controlling the influential factors such as secular trend, seasonal trend, and Sunday dummy variable; and analyzing the correlation between daily inhalable particle concentration, daily average temperature, and the number of daily SUD.</p><p><b>RESULTS</b>There was no statistical significance between the daily inhalable particle and daily incidence of sudden unexplained death. Incidence rate of sudden unexplained death had nonlinear positive correlation with daily temperature. When the temperature was 5°C above the daily average temperature, the daily incidence of sudden unexplained death went up with the rising temperature.</p><p><b>CONCLUSION</b>Temperature may be one of the key risk factor or precipitating factor of SUD.</p>

Time-series analysis of association between inhalable particulate matter and daily mortality among urban residents in Tianjin / 中华流行病学杂志

Objective To study the association between particulate matter less than 10 micron in aerodynamic diameter (PM10) and daily mortality among urban population in Tianjin.Methods We collected data of air quality, daily mean temperature and relative humidity, and daily cause-specific death counts, and used generalized additive models to explore the relationship between ambient particulate matter and daily mortality, after adjusting the effects of long-term and seasonal trend, weather conditions and other gaseous pollutants, such as sulfur dioxide and nitrogen dioxide.Results An increase of 10 μg/m3 in PM10 was associated with 0.45% (95%CI: 0.21-0.69) non-accidental morality, 0.60% (0.29-0.91) circulatory morality and 0.82% (0.04-1.61) respiratory morality, respectively. Conclusion Our findings indicated that the extent of exposure to PM10 was significantly associated with daily mortality in urban population in Tianjin, especially with the mortality rates on circulatory and respiratory diseases.

Time-series analysis on the association between gaseous air pollutants and daily mortality in urban residents in Tianjin / 中华流行病学杂志

Objective To study the association between sulphur dioxide, nitrogen dioxide and daily mortality in urban population from Tianjin. Methods Data on daily concentration of inhalable particulate matter, sulphur dioxide and nitrogen dioxide, daily mean temperature and relative humidity, daily cause-specific death counts were collected. Generalized additive models was used to explore the relationship between sulphur dioxide, nitrogen dioxide and daily mortality, after adjusting the effects of long-term and seasonal trend, weather conditions, and to analyze the potential effect of particulate matter and model parameters on relative risk estimates. Results Results showed that the daily concentrations of SO2 and NO2 were significantly associated with daily non-accidental and cardiovascular mortality but not associated with daily respiratory mortality. An increase of 10 μg/m3 in SO2 was associated with 0.56%(95%CI: 0.23%-0.89%)non-accidental morality, 0.49%(0.06%-0.93%)cardiovascular morality, respectively. An increase of 10μg/m3 in NO2 was associated with 0.94%(95% CI: 0.17%- 1.70%)non-accidental morality, 1.29%(0.29%-2.30%)cardiovascular morality, respectively. Conclusion Our findings suggested that exposure to SO2 and NO2 was significantly associated with daily cardiovascular and respiratory mortality in urban population in Tianjin.