Institute of Economy, Geography y Demography (IEGD), Spanish National Research Council (CSIC), Madrid, Spain.
Institute of Environmental Assessment and Water Research (IDAEA), Spanish National Research Council (CSIC), Barcelona, Spain.
Environ Health. 2023 Jan 13;22(1):5. doi: 10.1186/s12940-022-00957-6.
Although adaptation to continuously rising ambient temperatures is an emerging topic and has been widely studied at a global scale, detailed analysis of the joint indicators for long-term adaptation in Spain are scarce. This study aims to explore temporal variations of the minimum mortality temperature and mortality burden from heat and cold between 1979 and 2018.
We collected individual all-cause mortality and climate reanalysis data for 4 decades at a daily time step. To estimate the temperature-mortality association for each decade, we fitted a quasi-Poisson time-series regression model using a distributed lag non-linear model with 21 days of lag, controlling for trends and day of the week. We also calculated attributable mortality fractions by age and sex for heat and cold, defined as temperatures above and below the optimum temperature, which corresponds to the minimum mortality in each period.
We analysed over 14 million deaths registered in Spain between 1979 and 2018. The optimum temperature estimated at a nationwide scale declined from 21 °C in 1979-1988 to 16 °C in 1999-2008, and raised to 18 °C in 2009-2018. The mortality burden from moderate cold showed a 3-fold reduction down to 2.4% in 2009-2018. Since 1988-1999, the mortality risk attributable to moderate (extreme) heat reduced from 0.9% (0.8%) to 0.6% (0.5%). The mortality risk due to heat in women was almost 2 times larger than in men, and did not decrease over time.
Despite the progressively warmer temperatures in Spain, we observed a persistent flattening of the exposure-response curves, which marked an expansion of the uncertainty range of the optimal temperatures. Adaptation has been produced to some extent in a non-uniform manner with a substantial decrease in cold-related mortality, while for heat it became more apparent in the most recent decade only.
尽管适应不断升高的环境温度是一个新兴的话题，并在全球范围内得到了广泛研究，但西班牙长期适应的综合指标的详细分析仍然很少。本研究旨在探讨 1979 年至 2018 年期间最低死亡温度和热冷相关死亡负担的时间变化。
我们每天收集了 40 年来的个体全因死亡率和气候再分析数据。为了估计每个十年的温度-死亡率关系，我们使用具有 21 天滞后的分布式滞后非线性模型拟合准泊松时间序列回归模型，同时控制趋势和星期几。我们还计算了热和冷的归因死亡率分数，定义为高于和低于最佳温度的温度，最佳温度对应于每个时期的最低死亡率。
我们分析了 1979 年至 2018 年期间在西班牙登记的超过 1400 万例死亡。在全国范围内估计的最佳温度从 1979-1988 年的 21°C 下降到 1999-2008 年的 16°C，在 2009-2018 年上升到 18°C。中低温导致的死亡负担减少了三倍，降至 2009-2018 年的 2.4%。自 1988-1999 年以来，归因于中温（极温）热的死亡率风险从 0.9%（0.8%）降低到 0.6%（0.5%）。女性因热导致的死亡率几乎是男性的两倍，且并未随时间减少。
尽管西班牙的气温逐渐升高，但我们观察到暴露-反应曲线持续变平，这标志着最佳温度的不确定性范围扩大。适应已经以非均匀的方式进行，导致与低温相关的死亡率大幅下降，而对于高温，仅在最近十年才变得更加明显。
