Division of Biostatistics, School of Public Health and Primary Care, Chinese University of Hong Kong, Hong Kong.
Int J Cardiol. 2013 Sep 20;168(1):243-9. doi: 10.1016/j.ijcard.2012.09.087. Epub 2012 Oct 2.
Several previous studies examined the association between acute myocardial infarction (AMI) incidence and temperature and/or air pollution. Results of these studies have been inconsistent and few studies have been done in cities with sub-tropical or tropical climates.
Daily data on AMI hospitalizations, mean temperature and humidity, and pollutants, were collected for 2000-2009 for three warm-climate Asian cities. Poisson Generalized Additive Models were used to regress daily AMI counts on temperature, humidity, and pollutants while controlling for day of the week, long-term trends and seasonal effects. Smoothing splines allowing non-linear associations were used for temperature and humidity while pollutants were modeled as linear terms.
A 1°C drop below a threshold temperature of 24°C was significantly (p<.0001) associated with AMI hospitalization increases of 3.7% (average lag 0-13 temperature) in Hong Kong, 2.6% (average lag 0-15) in Taipei, and 4.0% (average lag 0-11) in Kaohsiung. No significant heat effects were observed. Among pollutants same day nitrogen dioxide (NO2) levels were the strongest predictors in all three cities, with a 10mg/m(3) increase in NO2 being associated with a 1.1% rise in AMI hospitalization in Hong Kong, and a 10 ppb rise being associated with 4.4% and 2.6% rises in Taipei and Kaohsiung, respectively.
Cool temperatures and higher NO2 levels substantially raised AMI risk in these warm-climate cities and the effect sizes we observed were stronger than those found in previous studies. More attention should be paid to the health dangers of cold weather in warm-climate cities.
已有多项研究探讨了急性心肌梗死（AMI）发病率与温度和/或空气污染之间的关系。 这些研究的结果并不一致，且在亚热带或热带气候的城市中进行的研究较少。
为 2000-2009 年期间的三个温暖气候的亚洲城市收集 AMI 住院、平均温度和湿度以及污染物的每日数据。 采用泊松广义加性模型，在控制星期几、长期趋势和季节性影响的情况下，将每日 AMI 计数与温度、湿度和污染物进行回归。 温度和湿度采用平滑样条函数以允许非线性关联，而污染物则采用线性项建模。
与 24°C 的阈值温度相比，每降低 1°C，与 AMI 住院增加相关（平均滞后 0-13 温度），在香港为 3.7%，在台北为 2.6%，在高雄为 4.0%。 未观察到明显的热效应。 在污染物中，在所有三个城市中，当天的二氧化氮（NO2）水平都是最强的预测指标，NO2 水平每增加 10mg/m3，与 AMI 住院增加 1.1%相关，在台北和高雄，NO2 水平每增加 10ppb，与 AMI 住院增加 4.4%和 2.6%相关。
在这些温暖气候的城市中，较低的温度和较高的 NO2 水平大大增加了 AMI 风险，我们观察到的效应大小强于以前的研究结果。 应更加关注温暖气候城市中寒冷天气对健康的危害。
