Lv Ling-Shuang, Yin Li, Liu Yuan, Zhou Chun-Liang, Hu Ji, An Ning, Xie Xian, Zhang Xing-E, Zhang Min, Liu Xiu-Ying
Hunan Provincial Center for Disease Control and Prevention, Changsha, 410153, China.
Int J Biometeorol. 2025 Mar;69(3):581-589. doi: 10.1007/s00484-024-02836-w. Epub 2024 Dec 3.
Heatwave and cold spell have been linked to cardiovascular disease (CVD) mortality. However, due to the varying definitions of heatwave and cold spell, their impacts on CVD mortality are inconsistent.
A time series study in Hunan province, central of China, from 2018 to 2022, was conducted to test the relationship between heatwave, cold spell and CVD mortality. According to different percentiles of daily mean temperatures and exposure duration, we built 9 kind of definitions for heatwave and cold spell. Distributed lag non-linear model was used to analyze the associations between heatwave, cold spell and CVD mortality, and the attributable fraction (AF) were estimated.
The relative risks of CVD mortality associated with heatwave and cold spell varied depending on the definitions, ranging from 1.154 (95% CI: 1.148-1.160) to 1.229 (95% CI: 1.215-1.243) for heatwaves, and from 1.196 (95% CI: 1.192-1.201) to 1.290 (95% CI: 1.282-1.297) for cold spells. Under the definition of 95th percentile with ≥ 4-d duration (P95_4d), the total AF of CVD mortality attributable to heatwave was the largest at 8.43 (95% CI: 7.92-8.94). For the definition of 5th percentile with ≥ 3-d duration (P5_3d), the total AF attributable to cold spell was the largest at 12.96 (95% CI: 12.64-13.28). For heatwave and cold spell, higher CVD mortality risks were observed in females and the elderly over 75 years than males and young people.
We found that both heatwave and cold spell could increase the mortality risk of CVD. The results highlight the importance of implementing warning systems for extreme temperature.
热浪和寒潮与心血管疾病（CVD）死亡率有关。然而，由于热浪和寒潮的定义不同，它们对CVD死亡率的影响并不一致。
在中国中部的湖南省进行了一项2018年至2022年的时间序列研究，以检验热浪、寒潮与CVD死亡率之间的关系。根据日平均温度的不同百分位数和暴露持续时间，我们构建了9种热浪和寒潮的定义。采用分布滞后非线性模型分析热浪、寒潮与CVD死亡率之间的关联，并估计归因分数（AF）。
与热浪和寒潮相关的CVD死亡率的相对风险因定义而异，热浪的相对风险范围为1.154（95%CI：1.148 - 1.160）至1.229（95%CI：1.215 - 1.243），寒潮的相对风险范围为1.196（95%CI：1.192 - 1.201）至1.290（95%CI：1.282 - 1.297）。在第95百分位数且持续时间≥4天（P95_4d）的定义下，归因于热浪的CVD死亡率的总AF最大，为8.43（95%CI：7.92 - 8.94）。在第5百分位数且持续时间≥3天（P5_3d）的定义下，归因于寒潮的总AF最大，为12.96（95%CI：12.64 - 13.28）。对于热浪和寒潮，75岁以上的女性和老年人比男性和年轻人观察到更高的CVD死亡风险。
我们发现热浪和寒潮都可能增加CVD的死亡风险。结果凸显了实施极端温度预警系统的重要性。
