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Fuelled by our changing climate, the summer of 2022 was one of the warmest on record, with numerous heatwaves and other weather extremes occurring around the globe. However, there is limited quantitative evidence on the contribution of human-induced warming to the weather-related health impacts observed in recent extreme weather events. We present a health attribution analysis of heat-related mortality attributable to human-induced climate change in the past summer of 2022 in Switzerland. We combined state-of-the-art methods in climate science and epidemiology with high-resolution mortality and temperature data to estimate the number and fraction of all-cause deaths that could be attributed to heat between June and August 2022. We, thus, estimated that 623 [95% CI: 151 - 1,068] all-cause deaths can be attributed to heat between June and August 2022, representing 3.5% [95% CI: 0.9-6.1] of total all-cause mortality during the same period. In a second step, we modelled counterfactual daily temperatures representing summer 2022 in absence of anthropogenic climate change. Specifically, four counterfactual daily mean temperature series were derived by subtracting the anthropogenic signal from the observed series which ranged between 1.19 and 2.75 ºC. Then, we quantified the hypothetical heat mortality burden in absence of climate change, and finally, estimate the contribution of climate change by subtracting it from the observed heat mortality impacts. We estimated that, in absence of an anthropogenic signal, the heat-related burden would have amounted to 1.4% [95% CI: -0.2 - 3.4] of all-cause mortality, corresponding to 253 deaths [95% CI: -27;594]. Thus, 2.1% [95% CI: 0.8 - 3.7] of the all-cause mortality in summer 2022 would have been avoided in absence of anthropogenic warming. This corresponds to 370 [95% CI: 133-644] deaths and 60% of the observed heat-mortality burden between June-August 2022. Females and the oldest age group were the most affected. Specifically, 60% of heat-related deaths attributed to climate change were in females (220 [69 - 393] vs. 150 [62 - 250] in males), and 90% in older adults (330 [129-565] vs. 39 [-5 - 84]). Our findings confirm that climate change is already affecting the health of the population in Switzerland by amplifying the heat-related mortality burden, with a stronger impact on females and older adults.

The risk of extreme heat mortality is ever increasing with the rapidly changing climate. However, several studies that project future levels of heat mortality have been criticized to be over-pessimistic, as these studies don’t reflect on communities’ ability to adapt to heat. Adaptation to heat is highly complex and not only complicated by the changing climate but also by other mega-trends such as ageing societies or urbanization. In this work, we therefore model future levels of heat-related mortality whilst incorporating location-specific empirical adaptation as a function of mean summer temperature and time.Concretely, we model the relationship between daily temperature and mortality by using quasi-Poisson regression time series analyses with distributed lag nonlinear models, which is a well-established approach in climate change epidemiology. The relationship expresses the change in mortality risk at specific temperature values against an optimum temperature (the so-called temperature of minimum mortality, MMT). We first model this relationship for continuous five-year intervals for several locations. Next, we express the change in MMT as a linear function of mean summer temperature and time. Adaptation is thus incorporated by shifting the MMTs according to future temperature levels and by when they are reached.This modelling approach allows us to assess heat mortality levels for different climate scenarios at the same level of global warming but at different points in time in the future. Potential findings of this approach are relevant, as the public debate and climate policy focuses largely on warming levels (1.5, 2°C) and to a lesser extent on how fast these levels are reached.

Although studies based on physiological models have repeatedly shown that high humidity levels lead to stronger heat stress in humans, findings from epidemiological studies have remained inconclusive on the matter till date. We aim to employ a ‘bottom-up’ strategy of identifying key drivers of compound events to explore the role played by humidity in high heat-related mortality events, spanning across multiple cities in multiple countries. We used daily data on all-cause mortality, mean temperature and mean relative humidity from 11 cities across the world and applied state-of-the-art epidemiological models to compute the daily observed total mortality counts attributable to heat (i.e., limited to days with average temperature exceeding the ‘temperature of minimum mortality’ (MMT) in each city). Each of these days with mean temperature exceeding MMT is considered as an ’event’ and events with highest mortality counts attributable to heat from multiple cities are analysed in a 2D scatter plot of the corresponding percentile rank of temperature and humidity observed during those events. The frequency of such high impact events in the temperature-humidity percentile space across multiple cities, categorised into sub-groups based on the temperature and humidity climatology of the cities, was then studied. It was observed that close to 90% of the high impact events occurred during high temperature (> 90th percentile) and non-high humid ( 50th percentile), were mostly representative of cities with prevailing high humidity conditions on average during the warmest months, when compared across all the cities. Based on our preliminary findings, there is no conclusive evidence that high humidity conditions were prevalent during high heat-mortality impact events, but further analysis incorporating more cities and other climatological variables of interests such as absolute humidity, wet-bulb globe temperature etc. are planned. This novel framework provides valuable insights into the role of humidity in heat stress mortality and can be generalised to address other similar complex research questions in environmental epidemiology.

BackgroundPrevious studies have found an association between warm temperature and asthma hospitalisation. They have reported different sex- and age-related vulnerabilities, nevertheless little is known about how this effect has changed over time and how it varies in space. This study aims to evaluate the association between asthma hospitalisation and warm temperature and investigate vulnerabilities by age, sex, time, and space.MethodsWe retrieved individual-level data on summer asthma hospitalisation at high temporal (daily) and spatial (postcodes) resolution during 2002-2019 in England from the NHS Digital. Daily mean temperature at 1km x 1km resolution was retrieved from the UK Met Office. We focused on lags 0-3 days. We employed a case-cross over study design and fitted Bayesian hierarchal Poisson models accounting for possible confounders (rainfall, relative humidity, wind speed, national holidays, and recurrent hospitalisations).ResultsAfter accounting for confounding, we found a 0.85% (95% Credible Interval: 0.64% to 1.07%) increase in the asthma hospitalisation risk for every 1°C increase in the ambient summer temperature. The effect was highest for males aged 15-65 (2.44%, 1.99% to 2.90%). During 2002-2007 we observed a 2.23% (1.86% to 2.60%) increase in hospitalisation risk per 1°C increase in temperature, whereas inconclusive evidence for the periods 2008-2013 and 2014-2019. Populations in Yorkshire and the Humber and East Midlands were the most vulnerable.ConclusionThis study provides evidence of an association between warm temperature and hospital admission for asthma, which was attenuated over time suggesting adaptive mechanisms to heat exposure or differences in lifestyle, comorbid conditions, and occupation over time.

Heat- and cold-related mortality risks are highly variable across different geographies, suggesting a differential distribution of vulnerability factors between and within countries, which could partly be driven by urban-to-rural disparities. Identifying these drivers of risk is crucial to characterize local vulnerability and design tailored public health interventions to improve adaptation of populations to climate change. We aimed to assess how heat- and cold-mortality risks change across urban, peri-urban and rural areas in Switzerland and to identify and compare the factors associated with increased vulnerability within and between different area typologies. We estimated the heat- and cold-related mortality association using the case time-series design and distributed lag non-linear models over daily mean temperature and all-cause mortality series between 1990–2017 in each municipality in Switzerland. Then, through multivariate meta-regression, we derived pooled heat and cold-mortality associations by typology (i.e. urban/rural/peri-urban) and assessed potential vulnerability factors among a wealth of demographic, socioeconomic, topographic, climatic, land use and other environmental data. Urban clusters reported larger pooled heat-related mortality risk (at 99th percentile, vs. temperature of minimum mortality (MMT)) (relative risk = 1.17 (95%CI: 1.10; 1.24), vs peri-urban 1.03 (1.00; 1.06), and rural 1.03 (0.99; 1.08)), but similar cold-mortality risk (at 1st percentile, vs. MMT) (1.35 (1.28; 1.43), vs rural 1.28 (1.14; 1.44) and peri-urban 1.39 (1.27–1.53)) clusters. We found different sets of vulnerability factors explaining the differential risk patterns across typologies. In urban clusters, mainly environmental factors (i.e. PM2.5) drove differences in heat-mortality association, while for peri-urban/rural clusters socio-economic variables were also important. For cold, socio-economic variables drove changes in vulnerability across all typologies, while environmental factors and ageing were other important drivers of larger vulnerability in peri-urban/rural clusters, with heterogeneity in the direction of the association. Our findings suggest that urban populations in Switzerland may be more vulnerable to heat, compared to rural locations, and different sets of vulnerability factors may drive these associations in each typology. Thus, future public health adaptation strategies should consider local and more tailored interventions rather than a one-size fits all approach.

Studies have shown that larger temperature-related health impacts may be associated with cold rather than with hot temperatures. Although it remains unclear the cold-related health burden in warmer regions, in particular at the national level in Brazil. We address this gap by examining the association between low ambient temperature and daily hospital admissions for cardiovascular and respiratory diseases in Brazil between 2008 and 2018. We first applied a case time series design in combination with distributed lag non-linear modeling (DLNM) framework to assess the association of low ambient temperature with daily hospital admissions by Brazilian region. Here, we also stratified the analyses by sex, age group (15-45, 46-65, and >65 years), and cause (respiratory and cardiovascular hospital admissions). In the second stage, we performed a meta-analysis to estimate pooled effects across the Brazilian regions. Our sample included more than 23 million hospitalizations for cardiovascular and respiratory diseases nationwide between 2008 and 2018, of which 53% were admissions for respiratory diseases and 47% for cardiovascular diseases. Our findings suggest that low temperatures are associated with a relative risk of 1.17 (95% CI: 1.07; 1.27) and 1.07 (95% CI: 1.01; 1.14) for cardiovascular and respiratory admissions in Brazil, respectively. The pooled national results indicate robust positive associations for cardiovascular and respiratory hospital admissions in most of the subgroup analyses. In particular, for cardiovascular hospital admissions, men and older adults (>65 years old) were slightly more impacted by cold exposure. For respiratory admissions, the results did not indicate differences among the population groups by sex and age. This study can help decision-makers to create adaptive measures to protect public health from the effects of cold temperature.

Global anthropogenic environmental degradations such as climate change are increasingly recognized as critical public health issues, on which human beings should urgently act in order to preserve sustainable conditions of living on Earth. "Planetary Health" is a breakthrough concept and emerging research field based on the recognition of the interdependent relationships between living organisms-both human and non-human-and their ecosystems. In that regards, there have been numerous calls by healthcare professionals for a greater recognition and adoption of Planetary Health perspective. At the same time, current Western healthcare systems are facing their limits when it comes to providing affordable, equitable and sustainable healthcare services. Furthermore, while hospital-centrism remains the dominant model of Western health systems, primary care and public health continue to be largely undervalued by policy makers. While healthcare services will have to adapt to the sanitary impacts of environmental degradations, they should also ambition to accompany and accelerate the societal transformations required to re-inscribe the functioning of human societies within planetary boundaries. The entire health system requires profound transformations to achieve this, with obviously a key role for public health. But we argue that the first line of care represented by primary care might also have an important role to play, with its holistic, interdisciplinary, and longitudinal approach to patients, strongly grounded in their living environments and communities. This will require however to redefine the roles, activities and organization of primary care actors to better integrate socio-environmental determinants of health, strengthen interprofessional collaborations, including non-medical collaborations and more generally develop new, environmentally-centered models of care. Furthermore, a planetary health perspective translated in primary care will require the strengthening of synergies between institutions and actors in the field of health and sustainability.

BackgroundThere is emerging evidence suggesting a link between ambient heat exposure and chronic obstructive pulmonary disease (COPD) hospitalisations. Individual and contextual characteristics can affect population vulnerabilities to COPD hospitalisation due to heat exposure. This study quantifies the effect of ambient heat on COPD hospitalisations and examines population vulnerabilities by age, sex, and contextual characteristics.MethodsIndividual data on COPD hospitalisation at high geographical resolution (postcodes) during 2007-2018 in England was retrieved from the small area health statistics unit. Maximum temperature at 1 km×1km resolution was available from the UK Met Office. We employed a case-cross over study design and fitted Bayesian conditional Poisson regression models. We adjusted for relative humidity and national holidays, and examined effect modification by age, sex, green space, average temperature, deprivation and urbanicity.ResultsAfter accounting for confounding, we found a 1.47% (95% Credible Interval 1.19% to 1.73%), increase in the hospitalisation risk for every 1°C increase in temperatures above 23.2°C (lags 0-2 days). We reported weak evidence of an effect modification by sex and age. We found a strong spatial determinant of the COPD hospitalisation risk due to heat exposure, that was alleviated when we accounted for contextual characteristics. 1 851 (95% CrI 1 576 to 2 079) COPD hospitalisations were associated with temperatures above 23.2°C annually.ConclusionOur study suggests that resources should be allocated to support the public health systems, for instance through developing or expanding heat-health alerts, to challenge the increasing future heat-related COPD hospitalisation burden.Key MessagesWhat is the key question?What is the short-term effect of heat exposure on COPD hospitalisation and which contextual/societal factors affect population vulnerability?What is the bottom line?For every 1°C increase in summer temperatures higher than 23.2°C, the risk of COPD hospitalisation increases by 1.47%, and populations in the North and in the South East are more vulnerable.Why read on?This large nationwide study in England using individual data quantifies the effect of heat exposure on COPD hospitalisations; these findings inform future policies regarding preparedness and resilience of public health systems against the increasing COPD burden due to the increasing temperatures.

Background and aim The associations between COVID-19 transmission and meteorological factors are scientifically debated. Several studies have been conducted worldwide, with inconsistent findings. However, often these studies had methodological issues, e.g., did not exclude important confounding factors, or had limited geographic or temporal resolution. Our aim was to quantify associations between temporal variations in COVID-19 incidence and meteorological variables globally. Methods We analysed data from 455 cities across 20 countries from 3 February to 31 October 2020. We used a time-series analysis that assumes a quasi-Poisson distribution of the cases and incorporates distributed lag non-linear modelling for the exposure associations at the city-level while considering effects of autocorrelation, long-term trends, and day of the week. The confounding by governmental measures was accounted for by incorporating the Oxford Governmental Stringency Index. The effects of daily mean air temperature, relative and absolute humidity, and UV radiation were estimated by applying a meta-regression of local estimates with multi-level random effects for location, country, and climatic zone. Results We found that air temperature and absolute humidity influenced the spread of COVID-19 over a lag period of 15 days. Pooling the estimates globally showed that overall low temperatures (7.5 °C compared to 17.0 °C) and low absolute humidity (6.0 g/m3 compared to 11.0 g/m3) were associated with higher COVID-19 incidence (RR temp =1.33 with 95%CI: 1.08; 1.64 and RR AH =1.33 with 95%CI: 1.12; 1.57). RH revealed no significant trend and for UV some evidence of a positive association was found. These results were robust to sensitivity analysis. However, the study results also emphasise the heterogeneity of these associations in different countries. Conclusion Globally, our results suggest that comparatively low temperatures and low absolute humidity were associated with increased risks of COVID-19 incidence. However, this study underlines regional heterogeneity of weather-related effects on COVID-19 transmission., This paper used Copernicus Climate Change Service (C3S) and Copernicus Atmosphere Monitoring Service (CAMS) information. Hence, the authors would like to thank the European Centre for Medium-Range Weather Forecasts (ECMWF) for its data generation on behalf of the European Union.

Identifying how greenspace impacts the temperature-mortality relationship in urban environments is crucial, especially given climate change and rapid urbanization. However, the effect modification of greenspace on heat-related mortality has been typically focused on a localized area or single country. This study examined the heat-mortality relationship among different greenspace levels in a global setting., This publication was developed under Assistance Agreement No. RD83587101 awarded by the U.S. Environmental Protection Agency to Yale University. It has not been formally reviewed by EPA. The views expressed in this document are solely those of the authors and do not necessarily reflect those of the Agency. EPA does not endorse any products or commercial services mentioned in this publication. Research reported in this publication was also supported by the National Institute on Minority Health and Health Disparities of the National Institutes of Health under Award Number R01MD012769. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Also, this work has been supported by the National Research Foundation of Korea (2021R1A6A3A03038675), Medical Research CouncilUK (MR/V034162/1 and MR/R013349/1), Natural Environment Research Council UK (Grant ID: NE/ R009384/1), Academy of Finland (Grant ID: 310372), European Union’s Horizon 2020 Project Exhaustion (Grant ID: 820655 and 874990), Czech Science Foundation (22-24920S), Emory University’s NIEHS-funded HERCULES Center (Grant ID: P30ES019776), and Grant CEX2018-000794-S funded by MCIN/AEI/ 10.13039/501100011033 The funders had no role in the design, data collection, analysis, interpretation of results, manuscript writing, or decision to publication.

The established evidence associating air pollution with health is limited to populations from specific regions. Further large-scale studies in several regions worldwide are needed to support the literature to date and encourage national governments to act. Brazil is an example of these regions where little research has been performed on a large scale. To address this gap, we conducted a study looking at the relationship between daily PM

Governments were enforced to respond to SARS-CoV-2 virus spread by taking a wide range of policy measures. Several studies have reported a decrease in air pollution following the enforcement of lockdown measures during the first wave of the COVID-19 pandemic. However, these investigations were mostly based on simple pre-post comparisons using past years as a reference, and did not assess the role of different policy interventions. These responses offered an unprecedented opportunity to assess the effectiveness of several interventions to reduce air pollution levels worldwide. Using an accurate representation of business-as-usual and lockdown air pollution scenarios, provided by Copernicus Atmosphere Monitoring Service (CAMS), we quantitatively evaluated the association between policies responses to the COVID-19 pandemic with changes in NO2, O3, PM2.5, and PM10 levels in 47 European cities. We also estimated the short-term mortality in the period of February-July 2020. An advanced spatio-temporal Bayesian non-linear mixed effect model was performed to determine the association between air pollutant levels and stringency indices as well as individual policy measures. The results indicate non-linear relationships, with a stronger decrease in NO2 and to a lesser extent PM10 and PM2.5 at very strict policy levels. Differences across interventions were also identified, actions linked to school/workplace closure, limitations on gatherings, and stay-at-home requirements had strong effects, while restrictions on internal movement and international travels showed little impact. The observed decrease in pollution potentially resulted in hundreds of avoided deaths across the European cities. This project provides information that can help inform future policies on air pollution reduction.

Many regions of the world are now facing more frequent and unprecedentedly large wildfires. However, the association between wildfire-related PMFor this time series study, data on daily counts of deaths for all causes, cardiovascular causes, and respiratory causes were collected from 749 cities in 43 countries and regions during 2000-16. Daily concentrations of wildfire-related PM65·6 million all-cause deaths, 15·1 million cardiovascular deaths, and 6·8 million respiratory deaths were included in our analyses. The pooled RRs of mortality associated with each 10 μg/mShort-term exposure to wildfire-related PMAustralian Research Council, Australian National HealthMedical Research Council.

It is uncertain what climate change could bring to populations and countries in the hot desert environment of the Arabian Peninsula. Not only because they are already hot, countries in this region also have unique demographic profiles, with migrant populations potentially more vulnerable and constituting a large share of the population. In Kuwait, two-thirds of the population are migrant workers and record-high temperatures are already common. We quantified the temperature-related mortality burdens in Kuwait in the mid- (2050–2059) and end-century (2090–2099) decades under moderate (SSP2-4.5) and extreme (SSP5-8.5) climate change scenarios. We fitted time series distributed lag non-linear models to estimate the baseline temperature–mortality relationship which was then applied to future daily mean temperatures from the latest available climate models to estimate decadal temperature-mortality burdens under the two scenarios. By mid-century, the average temperature in Kuwait is predicted to increase by 1.80 °C (SSP2-4.5) to 2.57 °C (SSP5-8.5), compared to a 2000–2009 baseline. By the end of the century, we could see an increase of up to 5.54 °C. In a moderate scenario, climate change would increase heat-related mortality by 5.1% (95% empirical confidence intervals: 0.8, 9.3) by end-century, whereas an extreme scenario increases heat-related mortality by 11.7% (2.7, 19.0). Heat-related mortality for non-Kuwaiti migrant workers could increase by 15.1% (4.6, 22.8). For every 100 deaths in Kuwait, 13.6 (−3.6, 25.8) could be attributed to heat driven by climate change by the end of the century. Climate change induced warming, even under more optimistic mitigation scenarios, may markedly increase heat-related mortality in Kuwait. Those who are already vulnerable, like migrant workers, could borne a larger impact from climate change.

On behalf of the Multi-Country Multi-City Collaborative (MCC) Research Network.Background & Aim: Climate change is considered the most important environmental threat to human health. Substantial mortality and morbidity burden have been directly or indirectly attributed to climate-sensitive environmental stressors. However, limited quantitative evidence exists on how much of this burden can be attributed to man-made influences on climate. In this large health attribution study, we aimed at quantifying the proportion of excess heat-related mortality attributed to anthropogenic climate change in recent decades across 626 locations across 41 countries in various regions of the world included in MCC database.Methods: We first estimated the location-specific heat-mortality associations through two-stage time-series analyses with quasi-Poisson regression with distributed lag non-linear models and multivariate multilevel meta-regression using observed data. We then quantified the heat-related excess mortality in each location using daily modelled series derived from historical (factual) and preindustrial control (counterfactual) simulations from 5 general circulation models (ISIMIP2b database) in the period between 1991 and 2019. We finally computed the proportion of heat-related excess mortality attributable to anthropogenic influences as the difference between the two scenarios, with associated measures of uncertainty.Results: We found a steep increase in level of warming, expressed as the difference in annual average temperature between scenarios, with an average increase of 1.0°C (from 0.7°C to 1.2°C) across the 626 locations between 1991 and 2019. Overall excess heat-mortality fractions of 1.92% [95% confidence interval: 0.41, 3.25] and 1.28% [0.20, 2.50] were estimated under the factual and counterfactual scenarios, respectively, with an overall difference of 0.76% [0.25,1.74]. This translates to 33% of historical heat-excess mortality that can be attributed to anthropogenic climate change. Larger proportions were found in North America (46%), Central America (47%), South America (43%), South Africa (48%), Middle-East Asia (61%), South East-Asia (50%) and Australia (42%), although highly imprecise in most of cases.Conclusions: Our findings suggest that current warming driven by anthropogenic influences is already responsible for a considerable proportion of the heat-related mortality burden. These results stress the importance of strengthening current mitigation strategies to reduce further warming of the planet and related health impacts.

Introduction: Children constitute a subgroup of potential high vulnerability to heat. However, few studies have specifically focused on it. Our aim was to examine the association between summer tem...