Rezaee Reza, Fathi Serveh, Maleki Afshin, Aboubakri Omid, Li Guoxing, Safari Mahdi, Sharafkhani Rahim, Zarei Mozhdeh
Environmental Health Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran.
Department of Occupational and Environmental Health Sciences, Peking University, School of Public Health, Beijing, China.
Int J Biometeorol. 2023 Dec;67(12):2081-2091. doi: 10.1007/s00484-023-02564-7. Epub 2023 Oct 16.
Compared to previous decade, impact of heat waves (HWs) on mortality in recent years needs to be discussed in Iran. We investigated temporal change in added impact of summer HWs on mortality in eight cities of Iran. The pooled length of HWs was compared between 2015-2022 and 2008-2014 using random and fixed-effects of meta-analysis regression model. The temporal change in impact of HWs was evaluated through interaction effect between crossbasis function of HW and year in a two-stage time varying model. In order to pool the reduced coefficients of each period, multivariate meta-regression model, including city-specific temperature and temperature range as heterogenicity factors, was used. In addition to relative risk (RR), attributable fraction (AF) of HW in the two periods was also estimated in each city. In the last years, the frequency of all HWs was higher and the weak HWs were significantly longer. The only significant RR was related to the lowest and low severe HWs which was observed in the second period. In terms of AF, compared to the strong HWs, all weak HWs caused a considerable excess mortality in all cities and second period. The subgroup analysis revealed that the significant impact in the second period was mainly related to females and elderlies. The increased risk and AF due to more frequent and longer HWs (weak HWs) in the last years highlights the need for mitigation strategies in the region. Because of uncertainty in the results of severe HWs, further elaborately investigation of the HWs is need.
与前十年相比，近年来热浪对伊朗死亡率的影响需要进行讨论。我们调查了伊朗八个城市夏季热浪对死亡率附加影响的时间变化。使用荟萃分析回归模型的随机效应和固定效应，比较了2015 - 2022年和2008 - 2014年热浪的汇总持续时间。通过两阶段时变模型中热浪交叉基函数与年份之间的交互效应，评估热浪影响的时间变化。为了汇总每个时期的缩减系数，使用了多变量荟萃回归模型，包括特定城市的温度和温度范围作为异质性因素。除了相对风险（RR），还在每个城市估计了两个时期热浪的归因分数（AF）。在过去几年中，所有热浪的频率更高，轻度热浪的持续时间明显更长。唯一显著的RR与最低和低强度严重热浪有关，这在第二个时期观察到。就AF而言，与强烈热浪相比，所有轻度热浪在所有城市和第二个时期都导致了相当多的超额死亡率。亚组分析表明，第二个时期的显著影响主要与女性和老年人有关。近年来，由于更频繁、持续时间更长的热浪（轻度热浪）导致的风险和AF增加，凸显了该地区采取缓解策略的必要性。由于严重热浪结果存在不确定性，需要对热浪进行进一步详细调查。
