While previous research on historical changes in heat-related mortality observed decreasing trends over the recent decades, future projections suggest increasing impact of heat on mortality in most regions of the world. This study aimed to analyse temporal changes in temperature-mortality relationships in Prague, Czech Republic in the warm season (May–September), using a daily mortality time series from 1982 to 2019. To investigate possible effect of adaptation to increasing temperature, we divided the study period into four decades (1980s–2010s). We used conditional Poisson regression models to identify decade-specific relative risk of heat-related mortality and to calculate the annual number of heat-attributable deaths and the heat-attributable fraction of total warm season deaths. We estimated their trends over the whole study period by a generalized additive model with non-parametric smoothing spline. Our results showed that the unprecedentedly hot 2010s was associated with approximately twice as large relative risk of heat-related mortality than in previous decades. This resulted in the reversal of the trend in heat-attributable mortality in the 1990s and its increase during the last two decades. Our findings highlight the importance of further improvement of adaptation measures such as heat-and-health warning systems to protect the heat-susceptible population.

虽然先前关于热相关死亡率历史变化的研究观察到近几十年来呈下降趋势，但未来的预测表明，热对世界大部分地区死亡率的影响越来越大。本研究旨在使用 1982 年至 2019 年的每日死亡率时间序列，分析捷克共和国布拉格在温暖季节（5 月至 9 月）温度与死亡率关系的时间变化。为了研究适应温度升高的可能影响，我们划分了研究期为四个十年（1980 年代至 2010 年代）。我们使用条件泊松回归模型来确定与热相关死亡率的十年特定相对风险，并计算热归因死亡的年度数量和暖季总死亡人数中的热归因比例。我们通过具有非参数平滑样条的广义加法模型估计了它们在整个研究期间的趋势。我们的研究结果表明，2010 年代前所未有的炎热与热相关死亡的相对风险大约是前几十年的两倍。这导致了 1990 年代热归因死亡率趋势的逆转，以及过去二十年的上升趋势。我们的研究结果强调了进一步改进适应措施的重要性，例如热和健康预警系统，以保护热敏感人群。这导致了 1990 年代热归因死亡率趋势的逆转，以及过去二十年的上升趋势。我们的研究结果强调了进一步改进适应措施的重要性，例如热和健康预警系统，以保护热敏感人群。这导致了 1990 年代热归因死亡率趋势的逆转，以及过去二十年的上升趋势。我们的研究结果强调了进一步改进适应措施的重要性，例如热和健康预警系统，以保护热敏感人群。