Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010, China.
Ningbo Meteorological Bureau, Ningbo 315000, China.
Environ Int. 2020 Oct;143:105889. doi: 10.1016/j.envint.2020.105889. Epub 2020 Jun 30.
Numerous studies have been conducted to project temperature-related mortality under climate change scenarios. However, most of the previous evidence has been limited to the total or non-accidental mortality, resulting in insufficient knowledge on the influence of climate change on different types of disease.
We aimed to project future temperature impact on mortality from 16 causes under multiple climate change models in a coastal city of China.
We first estimated the baseline exposure-response relationships between daily average temperature and cause-specific mortality during 2009-2018. Then, we acquired downscaled future temperature projections from 28 general circulation models (GCMs) under two Representative Concentration Pathway (RCP4.5 and RCP8.5). Finally, we combined these exposure-response associations with projected temperature to estimate the change in the temperature-related death burden in different future decades in comparison to the 2010 s, assuming no demographic changes and population acclimatization.
We found a consistently decreasing trend in cold-related mortality but a steep rise in heat-related mortality among 16 causes under climate change scenarios. Compared with the 2010 s, the net change in the fraction of total mortality attributable to temperature are projected to -0.54% (95% eCI: -1.69% to 0.71%) and -0.38% (95% eCI: -2.73% to 2.12%) at the end of the 21st century under RCP4.5 and RCP8.5, respectively. However, the magnitude of future cold and heat effects varied by different causes of death. A net reduction of future temperature-related death burden was observed among 10 out of 15 causes, with estimates ranging from -5.02% (95% eCI: -17.42% to 2.50%) in mental disorders to -1.01% (95% eCI: -5.56% to 3.28%) in chronic lower respiratory disease. Conversely, the rest diseases are projected to experience a potential net increase of temperature-related death burden, with estimates ranging from 0.44% (95% eCI: -4.40% to 6.02%) in ischemic heart disease and 4.80% (95% eCI: -0.04% to 9.84%) in external causes.
Our study indicates that the mortality burden of climate change varied greatly by the mortality categories. Further investigations are warranted to comprehensively understand the impacts of climate change on different types of disease across various regions.
已有大量研究针对气候变化情景下与温度相关的死亡人数进行预测。然而，之前的大多数证据仅限于总死亡人数或非意外死亡人数，因此对于气候变化对不同类型疾病的影响的了解还不够充分。
我们旨在预测中国沿海城市未来多种气候变化模型下 16 种死因的温度变化对死亡率的影响。
首先，我们在 2009-2018 年期间估计了每日平均温度与特定死因死亡率之间的基本暴露-反应关系。然后，我们从 28 个通用环流模型（GCMs）中获取了未来温度的降尺度预测结果，分为两个代表性浓度路径（RCP4.5 和 RCP8.5）。最后，我们将这些暴露-反应关系与预测的温度相结合，以估算与 21 世纪相比，不同未来几十年与温度相关的死亡负担的变化情况，假设人口结构不变且人口对温度变化有适应能力。
我们发现，在气候变化情景下，16 种死因中与寒冷相关的死亡人数呈持续下降趋势，而与炎热相关的死亡人数则急剧上升。与 21 世纪相比，在 RCP4.5 和 RCP8.5 下，到 21 世纪末，归因于温度的总死亡率的净变化预计分别为-0.54%（95%eCI：-1.69%至 0.71%）和-0.38%（95%eCI：-2.73%至 2.12%）。然而，未来寒冷和炎热影响的程度因不同的死亡原因而有所不同。在 15 种死因中有 10 种死因的未来温度相关死亡负担预计会减少，估计范围从精神障碍的-5.02%（95%eCI：-17.42%至 2.50%）到慢性下呼吸道疾病的-1.01%（95%eCI：-5.56%至 3.28%）。相反，预计其余疾病的与温度相关的死亡负担将出现潜在的净增加，估计范围从缺血性心脏病的 0.44%（95%eCI：-4.40%至 6.02%）到外部原因的 4.80%（95%eCI：-0.04%至 9.84%）。
我们的研究表明，气候变化导致的死亡负担在很大程度上因死亡类别而异。需要进一步的研究来全面了解气候变化对不同地区不同类型疾病的影响。
