Temperature-related hospitalization burden under climate change来自 https://www.nature.com/articles/s41586-025-09352-w## AbstractClimate change hasmarkedly increased adverse effects on human health and economic growth. However,few studies have differentiated the impacts of extreme temperatures at the city leveland analysed the future implications for human health under various climate change scenarios4,5,6. Here we leverage data on historical relationships amongsix kinds of climate-sensitive diseases (CSDs)andassociated hospitalizations and temperatures across 301 cities (more than 90% of all cities)and more than 7,000 hospitals in China, anduse a nonlinear distributed lag model.This study projectshospitalization risks associated with extreme temperaturesthrough to the year 2100 and develops the hospitalization burden economic index to assess the burden under three carbon emission scenarios across cities.Five dimensions, including spatial distribution, disease categories, population age groups, future time horizons and carbon emission development pathways, have been evaluated.Historical data indicate a higher incidence of temperature-related risks among the CSDs in northwestern and southwestern China. Notably,gestation-related disease risks are associated with increased vulnerability to extreme heat in specific regions.The projections show that under current thermal conditions without adaptations, the excess hospitalizations from extreme heat will reach 0.6, 3.8 and 5.1 million by 2100 under the low-, middle- and high-emission scenarios, respectively. These findings highlight the need for targeted mitigation strategies to reduce uneven climate-related hospitalization risks and economic burdens while accounting for differences in city geography, extreme temperatures, population groups and carbon emission development pathways.## Methods:This study firstuses a distributed lag nonlinear model (DLNM) and fixed-effects methods, and uses daily hospitalization data from more than 7,000 hospitals in 301 cities (accounting for more than 90% of all cities) across China between 2021 and 2023 tosystematically investigate the historical relationship between temperature fluctuations and hospital admissions(reported as relative risk (RR)), differentiating the health impacts of extreme heat and extreme cold across geographical locations and age groups. Specifically, the analysis included five CSD categories (circulatory, respiratory, endocrine/metabolic, psychiatric and genitourinary) and one gestation-related category (pregnancy, childbirth and puerperium-related conditions). This ‘5 1’ classification includes five for the general population and one specific to pregnant women, capturing both general and gestation-related climate-related health risks. Then, future excess hospitalization risks associated with extreme heat and cold temperatures under climate uncertainties through 2100 are projected by coupling climate change scenarios with shared socioeconomic pathways (SSPs): SSP1-2.6 (low-emission scenario), SSP2-4.5 (medium-emission scenario) and SSP5-8.5 (high-emission scenario). Finally, this study proposes the hospitalization burden economic index (HBEI) of excess temperature-related hospitalizations while considering future urban economic development trends. These analyses enhance the understanding of temperature-sensitive health outcomes, provide evidence to optimize the allocation of healthcare resources across climates, populations and disease, and further extend these insights into future time frames and alternative carbon emission scenarios.## Results:Impact of temperature on hospitalizationFig. 1: The impact of temperature on hospitalization.Future frequency of extreme temperaturesFig. 2: Future changes in the frequency of extreme heat and extreme cold temperature events.Future temperature–hospitalization risksFig. 3: Excess hospitalization risk in regions related to extreme heat and cold under the T1 threshold calculation for each future year (2030–2100).Future heat-related medical burdensFig. 4: Future excess heat-related hospitalization medical burden.