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Background: Wildfire activity is an important source of tropospheric ozone (O 3 ) pollution. However, no study to date has systematically examined the associations of wildfire-related O 3 exposure with mortality globally., Methods: We did a multicountry two-stage time series analysis. From the Multi-City Multi-Country (MCC) Collaborative Research Network, data on daily all-cause, cardiovascular, and respiratory deaths were obtained from 749 locations in 43 countries or areas, representing overlapping periods from Jan 1, 2000, to Dec 31, 2016. We estimated the daily concentration of wildfire-related O 3 in study locations using a chemical transport model, and then calibrated and downscaled O 3 estimates to a resolution of 0·25° × 0·25° (approximately 28 km 2 at the equator). Using a random-effects meta-analysis, we examined the associations of short-term wildfire-related O 3 exposure (lag period of 0-2 days) with daily mortality, first at the location level and then pooled at the country, regional, and global levels. Annual excess mortality fraction in each location attributable to wildfire-related O 3 was calculated with pooled effect estimates and used to obtain excess mortality fractions at country, regional, and global levels., Findings: Between 2000 and 2016, the highest maximum daily wildfire-related O 3 concentrations (≥30 μg/m 3 ) were observed in locations in South America, central America, and southeastern Asia, and the country of South Africa. Across all locations, an increase of 1 μg/m 3 in the mean daily concentration of wildfire-related O 3 during lag 0-2 days was associated with increases of 0·55% (95% CI 0·29 to 0·80) in daily all-cause mortality, 0·44% (-0·10 to 0·99) in daily cardiovascular mortality, and 0·82% (0·18 to 1·47) in daily respiratory mortality. The associations of daily mortality rates with wildfire-related O 3 exposure showed substantial geographical heterogeneity at the country and regional levels. Across all locations, estimated annual excess mortality fractions of 0·58% (95% CI 0·31 to 0·85; 31 606 deaths [95% CI 17 038 to 46 027]) for all-cause mortality, 0·41% (-0·10 to 0·91; 5249 [-1244 to 11 620]) for cardiovascular mortality, and 0·86% (0·18 to 1·51; 4657 [999 to 8206]) for respiratory mortality were attributable to short-term exposure to wildfire-related O 3 ., Interpretation: In this study, we observed an increase in all-cause and respiratory mortality associated with short-term wildfire-related O 3 exposure. Effective risk and smoke management strategies should be implemented to protect the public from the impacts of wildfires., Funding: Australian Research Council and the Australian National Health and Medical Research Council., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Brazil has experienced unprecedented wildfires recently. We aimed to investigate the association of wildfire-related fine particulate matter (PM 2.5 ) with cause-specific cardiovascular mortality, and to estimate the attributable mortality burden. Exposure to wildfire-related PM 2.5 was defined as exposure to annual mean wildfire-related PM 2.5 concentrations in the 1-year prior to death. The variant difference-in-differences method was employed to explore the wildfire-related PM 2.5 -cardiovascular mortality association. We found that, in Brazil, compared with the population in the first quartile (Q1: ≤1.82 μg/m 3 ) of wildfire-related PM 2.5 exposure, those in the fourth quartile (Q4: 4.22-17.12 μg/m 3 ) of wildfire-related PM 2.5 exposure had a 2.2% (RR: 1.022, 95% CI: 1.013-1.032) higher risk for total cardiovascular mortality, 3.1% (RR: 1.031, 95% CI: 1.014-1.048) for ischaemic heart disease mortality, and 2.0% (RR: 1.020, 95% CI: 1.002-1.038) for stroke mortality. From 2010 to 2018, an estimation of 35,847 (95% CI: 22,424-49,177) cardiovascular deaths, representing 17.77 (95% CI: 11.12-24.38) per 100,000 population, were attributable to wildfire-related PM 2.5 exposure. Targeted health promotion strategies should be developed for local governments to protect the public from the risk of wildfire-related cardiovascular premature deaths., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Model-estimated air pollution exposure products have been widely used in epidemiological studies to assess the health risks of particulate matter with diameters of ≤2.5 µm (PM2.5). However, few studies have assessed the disparities in health effects between model-estimated and station-observed PM2.5 exposures., Methods: We collected daily all-cause, respiratory and cardiovascular mortality data in 347 cities across 15 countries and regions worldwide based on the Multi-City Multi-Country collaborative research network. The station-observed PM2.5 data were obtained from official monitoring stations. The model-estimated global PM2.5 product was developed using a machine-learning approach. The associations between daily exposure to PM2.5 and mortality were evaluated using a two-stage analytical approach., Results: We included 15.8 million all-cause, 1.5 million respiratory and 4.5 million cardiovascular deaths from 2000 to 2018. Short-term exposure to PM2.5 was associated with a relative risk increase (RRI) of mortality from both station-observed and model-estimated exposures. Every 10-μg/m3 increase in the 2-day moving average PM2.5 was associated with overall RRIs of 0.67% (95% CI: 0.49 to 0.85), 0.68% (95% CI: -0.03 to 1.39) and 0.45% (95% CI: 0.08 to 0.82) for all-cause, respiratory, and cardiovascular mortality based on station-observed PM2.5 and RRIs of 0.87% (95% CI: 0.68 to 1.06), 0.81% (95% CI: 0.08 to 1.55) and 0.71% (95% CI: 0.32 to 1.09) based on model-estimated exposure, respectively., Conclusions: Mortality risks associated with daily PM2.5 exposure were consistent for both station-observed and model-estimated exposures, suggesting the reliability and potential applicability of the global PM2.5 product in epidemiological studies., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background: More intense cyclones are expected in the future as a result of climate change. A comprehensive review is urgently needed to summarize and update the evidence on the health effects of cyclones., Objectives: We aimed to provide a systematic review with meta-analysis of current evidence on the risks of all reported health outcomes related to cyclones and to identify research gaps and make recommendations for further research., Methods: We systematically searched five electronic databases (MEDLINE, Embase, PubMed, Scopus, and Web of Science) for relevant studies in English published before 21 December 2022. Following the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines, we developed inclusion criteria, screened the literature, and included epidemiological studies with a quantitative risk assessment of any mortality or morbidity-related outcomes associated with cyclone exposures. We extracted key data and assessed study quality for these studies and applied meta-analyses to quantify the overall effect estimate and the heterogeneity of comparable studies., Results: In total, 71 studies from eight countries (the United States, China, India, Japan, the Philippines, South Korea, Australia, Brazil), mostly the United States, were included in the review. These studies investigated the all-cause and cause-specific mortality, as well as morbidity related to injury, cardiovascular diseases (CVDs), respiratory diseases, infectious diseases, mental disorders, adverse birth outcomes, cancer, diabetes, and other outcomes (e.g., suicide rates, gender-based violence). Studies mostly included only one high-amplitude cyclone (cyclones with a Saffir-Simpson category of 4 or 5, i.e., Hurricanes Katrina or Sandy) and focused on mental disorders morbidity and all-cause mortality and hospitalizations. Consistently elevated risks of overall mental health morbidity, post-traumatic stress disorder (PTSD), as well as all-cause mortality or hospitalizations, were found to be associated with cyclones. However, the results for other outcomes were generally mixed or limited. A statistically significant overall relative risk of 1.09 [95% confidence interval (CI): 1.04, 1.13], 1.18 (95% CI: 1.12, 1.25), 1.15 (95% CI: 1.13, 1.18), 1.26 (95% CI: 1.05, 1.50) was observed for all-cause mortality, all-cause hospitalizations, respiratory disease, and chronic obstructive pulmonary disease hospitalizations, respectively, after cyclone exposures, whereas no statistically significant risks were identified for diabetes mortality, heart disease mortality, and preterm birth. High between-study heterogeneity was observed., Conclusions: There is generally consistent evidence supporting the notion that high-amplitude cyclones could significantly increase risks of mental disorders, especially for PTSD, as well as mortality and hospitalizations, but the evidence for other health outcomes, such as chronic diseases (e.g., CVDs, cancer, diabetes), and adverse birth outcomes remains limited or inconsistent. More studies with rigorous exposure assessment, of larger spatial and temporal scales, and using advanced modeling strategy are warranted in the future, especially for those small cyclone-prone countries or regions with low and middle incomes. https://doi.org/10.1289/EHP12158.

Background: In 2014, wildfires ignited a coal mine in Australia, burning for 6 weeks, releasing large amounts of fine particulate matter ≤2.5 μm in diameter (PM 2.5 ). We investigated the association between individual PM 2.5 exposure and emergency department presentations (EDPs) within 5 years post-fire., Methods: Survey and exposure data for 2725 residents from an exposed and unexposed town were linked with ED administrative data from 2009 to 2019. The association between individual PM 2.5 and EDPs was assessed using recurrent survival analysis., Results: A 10 μg/m 3 increase in PM 2.5 was associated with a 10% increase in respiratory EDPs (HR = 1.10; 95%CI:1.00-1.22) over 5 years post-fire. Increased risks of EDPs for ischaemic heart disease (HR = 1.39; 95%CI:1.12-1.73), atherothrombotic disease (HR = 1.27; 95%CI:1.08-1.50), and cardiovascular disease (HR = 1.10, 95%CI:0.99-1.22) were evident within 2.5 years., Conclusion: PM 2.5 exposure from a 6-week mine fire increased the 5-year risk of respiratory conditions. An increased risk of CVD within 2.5 years post-fire subsided after this time., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Michael Abramson reports a relationship with Pfizer that includes: funding grants. Michael Abramson reports a relationship with Boehringer-Ingelheim that includes: funding grants. Michael Abramson reports a relationship with Sanofi that includes: consulting or advisory and funding grants. Michael Abramson reports a relationship with GSK that includes: funding grants and speaking and lecture fees. Dion Stub reports a relationship with National Heart Foundation of Australia that includes: funding grants. Yuming Guo reports a relationship with Australian National Health and Medical Research Council that includes: funding grants., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The health effects of the unprecedented bushfires in Australia in 2019-20 have not been fully examined. We aimed to examine the excess emergency department (ED) visits related to the 2019-20 bushfires in New South Wales (NSW). We obtained weekly data of ED visits for cardiovascular and respiratory diseases in all the 28 Statistical Area Level 4 (SA4) regions in NSW during the bushfire seasons from 2017 to 2020. A two-stage interrupted time-series analysis was applied to quantify the excess risk for ED visits in 2019-20. The total number of excess ED visits, excess percentages, and their empirical confidence intervals (eCIs) were calculated to estimate the impacts of the bushfire season. A total of 416,057 records of cardiorespiratory ED visits were included in our analysis. The bushfire season in 2019-20 was significantly associated with a 6.0% increase (95% eCI: 1.9, 10.3) in ED visits for respiratory diseases and a 10.0% increase (95% eCI: 5.0, 15.2) for cardiovascular diseases, corresponding to 6177 (95% eCI: 1989, 10,166) and 3120 (95% eCI: 1628, 4544) excess ED visits, respectively. The percentage of excess ED visits was higher in regions with lower SES and high fire density. In the context of climate change, more targeted strategies should be developed to prevent adverse bushfire effects and recover from such extreme environmental events., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objectives: This study aimed to examine the association between early life famine exposure and adulthood cardiovascular diseases (CVDs) risk. Methods: A total of 5,504 subjects were selected using their birthdate from national baseline data of the China Health and Retirement Longitudinal Survey to analyze the association between famine exposure in early life and CVDs risk in adulthood. CVDs was defined based on the self-reported doctor's diagnosis. Results: The prevalence of CVDs in the unexposed group, fetal-exposed, infant-exposed, and preschool-exposed groups was 15.0%, 18.0%, 21.0%, and 18.3%, respectively. Compared with the unexposed group, fetal-exposed, infant-exposed and preschool-exposed groups had higher CVDs risk in adulthood ( p < 0.05). Compared with the age-matched control group, infancy exposed to famine had a significantly higher adulthood CVDs risk (OR = 1.52, 95% CI: 1.15, 2.01; p = 0.006). The association seems to be stronger among population with higher education level ( P interaction = 0.043). Sensitivity analysis revealed consistent association between early-life famine exposure and adult CVDs risk. Conclusion: Early life exposed to the China great famine may elevate the risk of CVDs in adulthood., Competing Interests: The authors declared that they had no competing interests., (Copyright © 2021 Wang, Dong, Xu, Wang, Li and Zou.)

Background: In the context of global warming, studies have turned to assess the temporal trend of the association between temperature and health outcomes, which can be used to reflect whether human beings have adapted to the local temperature. However, most studies have only focused on hot temperature and mortality. We aim to investigate the temporal variations in the association between ambient temperature and hospitalisations for cardiovascular diseases in Queensland, Australia from 1995 to 2016., Methods and Findings: We obtained data on 1,855,717 cardiovascular hospitalisations (mean age: 65.9 years, 42.7% female) from all 443 postal areas in Queensland, Australia between January 1, 1995 and December 31, 2016. Grid-level meteorological data were downloaded from scientific information for landowners. We used a time-stratified case-crossover design fitted with a conditional quasi-Poisson regression model and time-varying distributed lag nonlinear model (DLNM) to evaluate the association between temperature and cardiovascular hospitalisations and the temporal trends of the associations. Stratified analyses were performed in different age, sex, and climate zones. In all groups, relative risks (RRs) of cardiovascular hospitalisations associated with high temperatures (heat effects) increased, but cold effects showed a decreasing trend from 1995 to 2016. The increasing magnitude of heat effects was larger (p = 0.002) in men than in women and larger (p < 0.001) in people aged ≤69 years than in those aged ≥70 years. There was no apparent difference amongst different climate zones. The study was limited by the switch from ICD-9 to ICD-10 coding systems, by being unable to separate first-time hospitalisation from repeated hospitalisations, and possibly by confounding by air pollution or by influenza infections., Conclusion: The impacts of cold temperatures on cardiovascular hospitalisations have decreased, but the impacts of high temperatures have increased in Queensland, Australia. The findings highlight that Queensland people have adapted to the impacts of cold temperatures, but not high temperatures. The burden of cardiovascular hospitalisations due to high temperatures is likely to increase in the context of global warming., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: YG is a member of the Editorial Board of PLOS Medicine.