Institute of Epidemiology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
Institute of Epidemiology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.
BMJ. 2024 Oct 9;387:e080944. doi: 10.1136/bmj-2024-080944.
To examine the associations between characteristics of daily rainfall (intensity, duration, and frequency) and all cause, cardiovascular, and respiratory mortality.
Two stage time series analysis.
645 locations across 34 countries or regions.
Daily mortality data, comprising a total of 109 954 744 all cause, 31 164 161 cardiovascular, and 11 817 278 respiratory deaths from 1980 to 2020.
Association between daily mortality and rainfall events with return periods (the expected average time between occurrences of an extreme event of a certain magnitude) of one year, two years, and five years, with a 14 day lag period. A continuous relative intensity index was used to generate intensity-response curves to estimate mortality risks at a global scale.
During the study period, a total of 50 913 rainfall events with a one year return period, 8362 events with a two year return period, and 3301 events with a five year return period were identified. A day of extreme rainfall with a five year return period was significantly associated with increased daily all cause, cardiovascular, and respiratory mortality, with cumulative relative risks across 0-14 lag days of 1.08 (95% confidence interval 1.05 to 1.11), 1.05 (1.02 to 1.08), and 1.29 (1.19 to 1.39), respectively. Rainfall events with a two year return period were associated with respiratory mortality only, whereas no significant associations were found for events with a one year return period. Non-linear analysis revealed protective effects (relative risk <1) with moderate-heavy rainfall events, shifting to adverse effects (relative risk >1) with extreme intensities. Additionally, mortality risks from extreme rainfall events appeared to be modified by climate type, baseline variability in rainfall, and vegetation coverage, whereas the moderating effects of population density and income level were not significant. Locations with lower variability of baseline rainfall or scarce vegetation coverage showed higher risks.
Daily rainfall intensity is associated with varying health effects, with extreme events linked to an increasing relative risk for all cause, cardiovascular, and respiratory mortality. The observed associations varied with local climate and urban infrastructure.
研究日降雨量（强度、持续时间和频率）特征与全因、心血管和呼吸死亡率之间的关系。
两阶段时间序列分析。
34 个国家或地区的 645 个地点。
1980 年至 2020 年期间的每日死亡率数据，包括全因死亡 109954744 例、心血管死亡 31164161 例和呼吸死亡 11817278 例。
逐日死亡率与降雨事件的关系，降雨事件的重现期（特定量级极端事件发生的平均预期时间）为 1 年、2 年和 5 年，滞后时间为 14 天。采用连续相对强度指数生成强度-反应曲线，以估计全球范围内的死亡率风险。
在研究期间，共确定了 50913 次 1 年重现期的降雨事件、8362 次 2 年重现期的降雨事件和 3301 次 5 年重现期的降雨事件。5 年重现期的极端降雨日与全因、心血管和呼吸死亡的每日增加显著相关，0-14 天滞后日的累积相对风险分别为 1.08（95%置信区间 1.05 至 1.11）、1.05（1.02 至 1.08）和 1.29（1.19 至 1.39）。2 年重现期的降雨事件仅与呼吸死亡率相关，而 1 年重现期的降雨事件则没有显著关联。非线性分析显示，中度至重度降雨事件具有保护作用（相对风险<1），而极端强度则具有不利影响（相对风险>1）。此外，极端降雨事件的死亡率风险似乎受到气候类型、降雨基线变异性和植被覆盖的影响，而人口密度和收入水平的调节作用则不显著。基线降雨变异性较低或植被覆盖稀疏的地方风险较高。
日降雨量强度与不同的健康影响有关，极端事件与全因、心血管和呼吸死亡率的相对风险增加有关。观察到的关联因当地气候和城市基础设施而异。
