Achebak Hicham, Masselot Pierre, Gallo Elisa, Chen Zhao-Yue, Ballester Joan, Rey Grégoire, Gasparrini Antonio
Inserm, France Cohortes, Paris, France.
ISGlobal, Barcelona, Spain.
Environ Epidemiol. 2025 Sep 9;9(5):e414. doi: 10.1097/EE9.0000000000000414. eCollection 2025 Oct.
Vulnerability to nonoptimal temperatures varies from one geographical location to another, but the contextual factors accounting for these spatial differences are still poorly understood. We aimed to identify the community-level characteristics contributing to geographical disparities in heat-related and cold-related mortality risk in France.
We conducted a country-wide analysis using data on all-cause mortality, temperature, and contextual characteristics across 1,967 pseudo-cantons in France between 2004 and 2019. We first estimated the daily temperature-mortality association in each pseudo-canton using a time-series quasi-Poisson regression in combination with distributed lag nonlinear models, and then we fitted univariable and multivariable multivariate meta-regression models to assess the effect modification of the contextual factors on heat-related and cold-related mortality risk.
Over the 16-year study period, metropolitan France recorded 8,807,376 deaths out of an average population of 63·2 million inhabitants, which corresponds to an average annual mortality rate of 8.7 per 1,000 people. The country-level percent change (%CR) in mortality risk at the 1st and 99th daily temperature percentiles versus the minimum mortality temperature was, respectively, 31.2% (95% CI = 29.0, 33.5) and 11.0% (95% CI = 9.4, 15.5). The mortality risk associated with low temperatures was not modified by any of the contextual factors considered in the study, while the mortality risk associated with high temperatures was independently modified by NO pollution. Communities exposed to high levels of NO (i.e., cities or urban areas) had increased mortality risk from heat.
This study suggests that urban areas in France are more vulnerable to heat, compared to rural communities, and that this disparity is probably driven by air pollution (NO) and urban heat island. Reducing air pollution and mitigating urban heat island should be at the forefront of adaptation strategies to prevent heat-related health impacts.
对非最适宜温度的脆弱性因地理位置而异，但导致这些空间差异的背景因素仍知之甚少。我们旨在确定导致法国与热相关和与冷相关的死亡风险存在地理差异的社区层面特征。
我们利用2004年至2019年法国1967个虚拟行政区的全因死亡率、温度和背景特征数据进行了全国范围的分析。我们首先使用时间序列准泊松回归结合分布滞后非线性模型估计每个虚拟行政区的每日温度-死亡率关联，然后拟合单变量和多变量元回归模型，以评估背景因素对与热相关和与冷相关的死亡风险的效应修正。
在16年的研究期内，法国本土平均人口为6320万居民，记录了8807376例死亡，平均年死亡率为每1000人8.7例。与最低死亡率温度相比，第1和第99每日温度百分位数时的死亡率风险的国家层面百分比变化（%CR）分别为31.2%（95%CI = 29.0，33.5）和11.0%（95%CI = 9.4，15.5）。研究中考虑的任何背景因素均未改变与低温相关的死亡风险，而与高温相关的死亡风险独立地受到一氧化氮污染的改变。暴露于高浓度一氧化氮的社区（即城市或市区）因高温导致的死亡风险增加。
这项研究表明，与农村社区相比，法国城市地区更容易受到高温影响，这种差异可能是由空气污染（一氧化氮）和城市热岛效应驱动的。减少空气污染和缓解城市热岛效应应成为预防与高温相关的健康影响的适应策略的首要任务。
