Associations Between Extreme Temperatures and Cardiovascular Cause-Specific Mortality: Results From 27 Countries

Suicide and ill-defined/undetermined deaths in urban areas in Japan: a national database study, 2008-2022

BACKGROUND

Suicide deaths are defined as deaths due to "intentional self-harm" in accordance with the International Statistical Classification of Diseases and Related Health Problems 10th Revision. However, "ill-defined and unknown causes of mortality," "accidents," and "event of undetermined intent" may also account for hidden suicides. This study compared the state of deaths due to suicide and ill-defined/undetermined causes across urban areas in Japan over the past 15 years using vital statistics.

METHODS

We analyzed vital statistics data including information on all deaths identified under suicide and ill-defined/undetermined death category among Japanese citizens aged ≥10 years who lived in a government ordinance-designated city between 2008 and 2022. Standardized mortality ratios (SMRs) were calculated for each cause of death and compared among designated cities.

RESULTS

Mortality rates due to "intentional self-harm" for those aged ≥65 years decreased during the study period, whereas mortality rates due to "ill-defined and unknown causes of mortality" for those aged ≥65 years sharply increased by nearly three times. Substantial differences in SMRs for "ill-defined and unknown causes of mortality" were observed among designated cities. There was no significant change in SMRs between the pre- and peri-COVID-19 pandemic periods in each designated city.

CONCLUSIONS

In Japan, the state of deaths due to "ill-defined and unknown causes of mortality" substantially differed among designated cities. Attention must be paid to changes in the state of deaths due to ill-defined/undetermined causes as well as suicide deaths.

Attending to the effects of outdoor temperature on blood pressure: Multicenter study based on ambulatory monitoring

Sudden fluctuations in blood pressure (BP) over a short period may trigger cardiovascular events, and outdoor temperature may be a risk factor. There is a lack of conclusive observational evidence linked hourly temperature with ambulatory BP indicators. We aimed to explore the effects of hourly outdoor temperature on ambulatory BP, BP variability and load. A large-scale, multicenter study among 31,838 adults from 7 Chinese cities was conducted between March 2016 and November 2020. Hourly temperature was obtained from the nearest weather stations. We collected ambulatory systolic (SBP), diastolic blood pressure (DBP), the BP variability and load of the day, and used linear mixed-effect model combined with distributed lag model to analyze data. Outdoor temperature was inversely associated with most ambulatory BP indicators. The effects of low temperature on BP appeared and peaked at the concurrent hour, then gradually attenuated and disappeared around at lag 20h. Compared to the referent temperature (P99), exposure to low temperature (P1) was associated with cumulative increments (over lag 0-20 h) of 9.71 mmHg, 4.85 mmHg and 20.58 mmHg for 24-h, nighttime and morning SBP, respectively, as well as 8.71 mmHg, 4.72 mmHg and 14.32 mmHg for 24-h, nighttime and morning DBP. Furthermore, there were significant associations between decreasing temperature and increased BP variability and load at lag 0 d. Our study provides compelling evidence that low temperature can elevate BP-related indicators, underscoring the necessity of flexible treatment strategies and targeted public health interventions, especially for susceptible populations during the cold season.

Extreme heat and hospital admissions in older adults: A small-area analysis in the Greater Boston metropolitan area

Extreme heat (EH) is a leading cause of weather-related fatalities in the United States. In Massachusetts, average temperatures have increased by 1.9 °C since the 20th century, higher than the global average increase of 1.1 °C. EH disproportionately impacts communities, exacerbating social inequities. This study examined the risks of heat-related hospitalizations in each small area of the Greater Boston Metropolitan Area using Medicare data (2000-2016). EH events included daily heat index (HI), days with an HI above the 90th percentile, and heat waves (≥2 consecutive EH days). We applied a case-crossover design to estimate area-specific associations between EH and hospitalizations and assessed effect modifications by an individual (age ≥85, sex, Medicaid dual eligibility) and ZIP-code characteristics (green space, poverty, educational attainment, and household income). Results were pooled using random effects meta-analysis. Area-specific analysis revealed higher hospitalization risks in Boston compared with surrounding areas. Pooled results indicated heat-related hospitalizations increased by 9.0% (95% CI = 5.7, 12.3) per 10 °C rise in HI, 14.4% (95% CI = 8.8, 20.3) on EH days, and 17.9% (95% CI = 11.1, 25.1) during heat waves. Risks were more pronounced in Boston, and some indications of elevated risk among males and residents in low-income, low-education areas. These findings underscore that heat-related health risks may be different across the level of geographic units and suggest the need for targeted public health strategies to mitigate the impacts of EH.

Compound drought and heatwave extreme weather events: Mortality risk in individuals with chronic respiratory disease

Background

Compound extreme weather events are severe weather conditions that can jointly magnify human health risks beyond any single event alone. Drought and heatwaves are extreme weather conditions associated with adverse health, but their combined impact is poorly understood.

Methods

We designed a case-crossover study to estimate heatwave-associated mortality stratified by drought conditions in 183,725 US Veteran patients (2016-2021) with chronic obstructive pulmonary disease (COPD). A conditional logistic regression with distributed lag models was applied. Droughts were categorized into binary and categorical metrics, and we further explored the timing of heatwaves as a risk factor.

Results

Our results indicate that drought amplifies heatwaves with hotter temperatures and longer durations during drought conditions, and the percentage of mortality attributable to heatwaves during drought was 7.41% (95% confidence interval [CI]: 2.91, 12.28) compared with 2.91% (95% CI: 0.00, 4.76) for heatwaves during nondrought conditions. Heatwaves that occurred during drought conditions in the late warm season had a larger association with mortality compared with late-season heatwaves during nondrought conditions, 7.41% (95% CI: 1.96, 13.04) of mortality events and 0.99% (95% CI: -1.01, 3.85) of mortality events attributable to these exposures, respectively.

Conclusion

Compound drought and heatwave events trend toward increased mortality risk among patients with COPD and present a growing human health threat under climate change. Existing heat warnings and vulnerability maps may include drought conditions to better capture heat-related public health risks.

Cardiovascular risk posed by the exposome

Chronic non-communicable diseases (NCDs) account for 2/3 of global deaths annually, primarily due to an aging population and external risk factors such as air/water/soil pollution, traffic noise, mental stress, and climate change emanating from the environment. These factors contribute to premature deaths and loss of healthy life years, as reflected by disability-adjusted life years. The exposome concept was proposed 16 years ago as a new research field to investigate environment-health associations, also by considering the underlying pathophysiological pathways. The exposome describes lifelong environmental exposures, besides pollutants also socioeconomic and lifestyle factors, aiming to explain the associated diseases and deaths. The exposome can be divided into the specific and general external environment and further subcategories such as organ-specific exposomes as well as spatially and temporally restricted pollutomes. The exposome also shows considerable interaction with genetic predisposition and pre-established chronic diseases, characteristics of the vulnerable groups. The present overview provides background information on the impact of the environment on health and disease by considering recent data of the Global Burden of Disease Study. We also explain the exposome concept with the help of selected studies, briefly describe how the exposome is measured, and discuss biomarkers identified by exposomic research and their impact on the development and progression of atherosclerosis. Major pathophysiological pathways comprise exacerbated stress hormone signaling, oxidative stress, inflammation and circadian rhythm dysregulation promoting impairment of cardiometabolic function. The present overview highlights the relevance of the exposome for future health research and preventive medicine, especially concerning cardiovascular diseases and therapy.

Temperature Exposure and Acute Cardiovascular Disease Risk in New York City: Case Time Series

BACKGROUND

Numerous studies investigated the associations between myocardial infarction (MI), ischemic stroke, and temperature exposure, but the results vary widely, particularly in dense metropolitan areas.

METHODS

We included all patients admitted to Mount Sinai hospitals with MI or ischemic stroke (2011-2019). We obtained daily mean, minimal, maximal, and diurnal temperature range (DTR) exposures from geospatial models. We used distributed lag nonlinear models in a case time series design to study the cumulative associations of each outcome with exposure to the different temperature metrics at lag days 0 to 6.

RESULTS

We included 8933 individuals. We found cumulative higher odds of ischemic stroke associated with higher mean (odds ratio [OR], 1.010 [95% CI, 1.004-1.016]); maximal (OR, 1.010 [95% CI, 1.004-1.015]) and minimal temperatures (OR, 1.011 [95% CI, 1.004-1.017]) on 0 to 6 days before the event. We observed a nonlinear association between DTR and MI. Comparing exposure at the 10th percentile of DTR (3.8 °C) to the median (8 °C), we observed an OR of 1.332 (95% CI, 1.164-1.528), with similar effect estimates across lags. The OR of MI among those exposed to 12 °C (the 90th percentile of DTR) compared with the median was 1.041 (95% CI, 0.932-1.163).

CONCLUSIONS

We found higher odds of ischemic stroke associated with increased temperature exposures, highlighting the potential stroke risks in a warming climate. Additionally, we found higher odds of MI associated with lower DTR, a pattern more common on colder days. This suggests DTR may capture cardiac effects not observed using traditional exposure metrics.

Differentiating the impact of non-optimum temperature and temperature variability on cause-specific cerebrovascular mortality: An individual-level, case-crossover study in Shanghai, China

BACKGROUND

Cerebrovascular mortality exhibits seasonal variation, but the roles of temperature and temperature variability (TV) in cause-specific cerebrovascular mortality remain unclear.

METHODS

This individual-level time-stratified case-crossover research collected individual cerebrovascular death records during 2005-2021 in Shanghai, China. TV was calculated as the standard deviation of daily minimum and maximum temperature over consecutive days. Conditional logistic regression models combined with distributed lag nonlinear models were utilized to evaluate the cumulative exposure-response associations.

RESULTS

Based on a total of 388,823 cerebrovascular deaths, we found that exposure to extreme cold, extreme heat, and greater TV was significantly related to increased cause-specific cerebrovascular mortality. Extreme cold exhibited the strongest impact on hemorrhagic stroke [relative risk (RR) = 1.84; 95 % confidence interval (CI): 1.50, 2.26], followed by hemorrhagic stroke sequelae [1.75 (95 % CI: 1.25, 2.45)] and cerebrovascular sequelae [1.71 (95 % CI: 1.58, 1.86)]. Extreme heat showed the largest effect on cerebrovascular sequelae [1.35 (95 % CI: 1.29, 1.41)], followed by ischemic stroke sequelae [1.34 (95 % CI: 1.28, 1.41)]. TV was associated with the largest percentage increase in ischemic stroke sequelae [2.12 % (95 % CI: 1.35 %, 2.90 %)], followed by cerebrovascular sequelae [1.95 % (95 % CI: 1.23 %, 2.68 %)]. Stratified analyses revealed stronger associations in the elders, singles, and those with low education.

CONCLUSIONS

This case-crossover study provides the first-hand evidence that extreme temperatures and TV may elevate the risk of cause-specific cerebrovascular mortality, which underscore the urgency of implementing targeted protective measures for cerebrovascular patients facing extreme weather events, particularly among aging populations in megacities under climate change.

Low and high air temperature and cardiovascular risk

Temperature extremes are one facet of global warming caused by climate change. They have a broad impact on population health globally. Due to specific individual- and area-level factors, some subgroups of the population are at particular risk. Observational data has demonstrated that the association between temperature and mortality and cardiovascular mortality is U- or J-shaped. This means that beyond an optimal temperature, both low and high temperatures increase cardiovascular risk. In addition, there is emerging epidemiological data showing that climate change-related temperature fluctuations may be particularly challenging for cardiovascular health. Biological plausibility for these observations comes from the effect of cold, heat, and temperature fluctuations on risk factors for cardiovascular disease. Shared mechanisms of heat and cold adaptation include sympathetic activation, changes in vascular tone, increased cardiac strain, and inflammatory and prothrombotic stimuli. The confluence of these mechanisms can result in demand ischemia and/or atherosclerotic plaque rupture. In conclusion, public health and individual-level measures should be taken to protect susceptible populations, such as patients with risk factors and/or pre-existing cardiovascular disease, from the adverse effects of non-optimal temperatures. This review aims to provide an overview of the association between temperature extremes and cardiovascular disease through the lens of pathophysiology and observational data. It also highlights some specific meteorological aspects, gives insight to the interplay of air temperature and air pollution, touches upon social dimensions of climate change, and tries to give a brief outlook into what to expect from the future.

Establishing and mapping heat-sensitive disease spectrum in eastern China: A comprehensive analysis of 1.4 million deaths involving 14 major disease categories

BACKGROUND

Although high temperatures can affect multiple systems and organs, the comprehensive assessment of heat-sensitive diseases remains unclear. We aimed to establish the heat-related sensitive disease spectrum and assess the relative importance of affected diseases from the health risk and burden perspectives.

METHODS

A space-time-stratified case-crossover analysis was used to examine the short-term association between high temperatures and cause-specific deaths in Jiangsu Province, China during the warm season of 2016 to 2019. A total of 14 major disease categories and 29 specific diseases were tested to identify heat-sensitive diseases. A multi-level comparison of heat-affected diseases was conducted based on the health risk and burden indicators including mortality risk, years of life lost (YLL) to measure disease burden, and value of YLL (VYLL) to measure economic burden.

RESULTS

High temperatures were associated with an increased risk of mortality from 23 specific diseases involving 12 major disease categories, including well-studied cardiovascular, respiratory, endocrine, and nervous diseases, and less-studied skin, urinary system diseases, mental and behavioral disorders, external causes, injury and poisoning, symptoms, signs and abnormal clinical, and neoplasms. The top three greatest heat-related risks of mortality from major disease categories were skin system (OR: 1.72, 95 % CI: 1.37-2.36), external causes of mortality (OR: 1.71, 95 % CI: 1.57-1.87), and nervous system (OR: 1.46, 95 % CI: 1.26-1.68), and cause-specific diseases were asthma (OR: 2.26, 95 % CI: 1.46-3.50), accidental drowning (OR: 1.85, 95 % CI: 1.42-2.40), and acute respiratory infections (OR: 1.80, 95 % CI: 1.02-3.16). In terms of both disease and economic burdens attributable to heat, cardiovascular diseases contributed to the greatest proportion, followed by neoplasms, external causes, and respiratory diseases. Within specific diseases, cerebrovascular diseases contributed the greatest disease and economic burdens, followed by ischemic heart disease, lung (neoplasm), and COPD. Furthermore, the largest heat-related reduction in life expectancy reached 5.27 years for external causes and 12.96 years for accidental drowning.

CONCLUSION

This study provides a heat-sensitive disease spectrum and resulting death risk and burden vary by different systems and specific diseases. Our findings may have implications for implementing heat-health action plans to mitigate the adverse effects of heat-sensitive diseases.

Exposure to greenness modifies the association between extreme temperature events and ischemic stroke recurrence in Tianjin, China

Few studies have found an association between extreme temperature events and an increased risk of recurrent ischemic stroke (IS). We examined associations between extreme temperature events (heat waves, cold spells) and recurrent IS risk in Tianjin, China (2019-2020), using a time-stratified case-crossover design, while evaluating greenness's moderating role. Significant heat wave effects peaked at lag 8, with severe intensity events increasing IS recurrence risk by 39.8% (OR = 1.398, 95% CI:1.032-1.894). Cold spell impacts peaked at lag 3, with moderate intensity cold spells elevating risk by 20.3% (OR = 1.203, 95% CI: 1.052-1.377) and severe intensity cold spells elevating risk by 98.2% (OR = 1.982, 95% CI: 1.407-2.791). Greenness modified these associations: low-greenness areas strengthened heat wave effects(lag9:OR = 2.309,95%CI:1.024-5.209) but weakened cold spell impacts(OR = 1.557,95%CI:1.037-2.340), whereas high-greenness areas attenuated heat wave links(lag8:OR = 1.402,95%CI:1.022-1.924) and nullified cold spell associations. Age and sex disparities emerged - younger individuals and males showed higher susceptibility to heat waves, while older individuals and males were more vulnerable to cold spells. The findings highlight greenness as a potential modifier of extreme temperature events-related IS recurrence risks and underscore demographic-specific vulnerabilities.

Environmental pollution and cardiovascular health. Challenges and new perspectives

Environmental pollution is a key factor in cardiovascular disease (CVD) development. Several evidences support its impact at the pathophysiology of arteriosclerosis, highlighting the role of the "exposome", a concept that encompasses all environmental factors such as air pollution, water pollution, climate change and noise and light pollution. These factors are associated with an increased risk of ischemic heart disease (IHD), stroke, high blood pressure (HBP), heart failure (HF) and atrial fibrillation (AF). Currently, air pollution is the main environmental factor related to CVD. Components such as particulates matter (PM0.1, PM2.5, PM10), sulfur dioxide (SO2), nitrogen oxide and dioxide (NOx), carbon monoxide (CO) and ozone (O3) have a high capacity to penetrate the body and trigger both local and systemic inflammatory processes. These effects promote a proinflammatory, procoagulant state and an increase in oxidative stress. Similarly, aquatic pollution exposes the body to pollutants such as heavy metals, pesticides and microplastics, both through direct contact and via the food chain, thus contributing to the phenomena mentioned above. On the other hand, factors such as noise and light pollution, together with effects caused from climate change (extreme temperatures, wildfires, desertification, among others), have been closely linked to pathophysiological processes that favour the development and progression of atherosclerosis. These mechanisms include sympathetic nervous system (SNS) activation, stress hormones release such as cortisol and catecholamines, as well as chronodisruption. This review analyses the role of factors related to the exposome (air pollution, water pollution, noise and light pollution and phenomena associated with climate change) in atherosclerosis progression, as well as their involvement in the incidence, prevalence and prognosis of CVD. Physicians should promote awareness of environmental pollution impact on cardiovascular health, integrating the assessment of environmental factors into their clinical practice, advocating for sustainable policies to prevent diseases and protect present and future health.

The Effects of Quercetin on Vascular Endothelium, Inflammation, Cardiovascular Disease and Lipid Metabolism-A Review

Quercetin is a naturally occurring flavonoid of plant origin. This naturally occurring polyphenolic compound is generally known for its antioxidant and anti-inflammatory properties and has been reported to be a factor in improving the antioxidant defense system, lipid metabolism, and reducing the incidence of cardiovascular and inflammatory diseases. In this article, we will take a closer look at quercetin-what it is, what properties it has, what health benefits it can bring, and in which products it can be found. Thanks to its wide spectrum of action, quercetin is gaining popularity as an ingredient in dietary supplements, as well as an element of a healthy diet supporting overall health.

Association of cold weather and influenza infection with stroke: a 22-year time-series analysis

Despite the significant adverse health effects and economic burden of stroke inpatients, there has been a paucity of research specifically analyzing and quantifying the association between meteorological factors, air pollutants, influenza infection, and stroke admissions. This study assessed the impact of environmental factors and influenza activity on stroke admissions in Hong Kong from 1998 to 2019, utilizing population-based records. We employed the number of weekly stroke admissions as the primary outcome measure and matched the number with meteorological factors and air pollutant concentrations. Strain-specific influenza-like illness-positive (ILI+) rates were used as a proxy indicator of influenza activity. A quasi-Poisson generalized additive model in combination with a distributed-lag non-linear model (DLNM) was employed to elucidate the relationship of interest. Over the 22-year period, a total of 1,170,882 stroke-related admissions were recorded in Hong Kong. The cumulative adjusted relative risk (ARR) of stroke admission was significantly increased (cumulative ARR = 1.106, 95% CI, 1.069-1.143) at the 5th percentile of temperature (i.e., 15.08 °C) compared with the median reference level. Using zero as the reference value, the cumulative adjusted relative risks of stroke admission were 1.030 (95% CI, 1.018-1.042) at the 95th percentile of ILI + A/H1N1 rate, and 1.022 (95% CI, 1.007-1.038) at the 95th percentile of ILI + total rate. In conclusion, cold weather and influenza infection are risk factors to stroke admissions. Public health strategies for preventing stroke should be considered such as advocating influenza vaccination programmes during winter.

Effect of compound exposure to snowstorm and cold spell on acute myocardial infarction mortality

Cold weather events such as cold spell and snowstorm could trigger heart attacks, but the effect of compound exposure to cold weather events remains unknown. This study aimed to estimate and compare the effect of independent and compound exposure to common cold weather events (cold spell and snowstorm) on acute myocardial infarction (AMI) mortality. Daily data on AMI deaths (74,279) and weather conditions were collected in a subtropical-temperate climate transit region of China from 2016 to 2020. We conducted a space-time-stratified case-crossover analysis to fit the association of AMI mortality with cold spell and snowstorm. We observed an increased AMI death risk associated with independent and compound exposure to cold spell or snowstorm. Furthermore, the association of compound exposure to cold spell and snowstorm was greater than the independent exposure but varied by the compound types. A greater risk was observed if the snowstorm and cold spell occurred on the same day [odds ratio (OR): 1.197 (95% confidence interval (CI): 1.153-1.243)] than the scenario that the snowstorm was followed by cold spell [OR: 1.100 (95%CI: 1.079-1.121)] or the cold spell was followed by snowstorm [OR: 1.115 (95%CI: 1.075-1.157)]. This study suggests that compound exposure to cold spell and snowstorm not only has a greater effect on AMI death risk than independent exposure but also differs by the compound types.

Temperature extremes and human health in Cyprus: Investigating the impact of heat and cold waves

In Mediterranean countries like Cyprus, extreme temperatures and especially heatwaves during summer months are increasingly common, leading to heightened bio-climatic stress. While coldwaves are less frequent and understudied in this region, they still pose significant health risks. This study utilizes temperature data from ERA5-Land in conjunction with mortality and hospitalization data from Cyprus. Employing statistical machine learning methods such as Distributed Lag Models (DLMs) and Generalized Additive Models (GAMs), mortality and hospitalization risks for major health concerns in Cyprus, along with attributable deaths and hospital admissions associated with temperature fluctuations and extreme events over two seasons, were estimated. This study also examines temperature trends over the past four decades in Cyprus, noting a significant increase in both maximum and minimum temperatures as well as an increase in extreme high-temperature days and a decrease in extreme low-temperature days. For mortality, elevated risks were identified at very high temperatures, peaking at shorter lags with up to a 7.5% above-average risk, which further increased to 14.3% during heatwave events in the warm season. Conversely, mortality risks at very low temperatures during the cold season reached 4.2% particularly for longer lag days. Hospitalization risks were notably higher during periods of cold temperatures. Importantly, our findings confirm that cold-related mortality exceeds heat-related mortality in absolute terms. However, during heatwave days, the rate of increase in attributable deaths is five times higher compared to typical days in the warm season, whereas for cold days it is about twice as high as on non-cold days.

Stroke risk associated with cold spells occurring during the warm season

BACKGROUND

Recent climate changes have resulted in a rising frequency of extreme cold events that take place during the warm season. Few studies have investigated the impact of these warm-season cold spells on cardiovascular health. Here, we aimed to investigate the potential relationship between exposure to relatively low temperature exposure during the warm season and stroke risk.

METHODS

We conducted a time-stratified case-crossover study using a validated, complete, and detailed registration of all stroke cases in the city of Augsburg, Germany, from 2006 to 2020 to assess the association between the occurrence of stroke and exposure to cold spell events during the warm season (May-October). Six cold spell definitions were created using different relative temperature thresholds (1st, 2.5th, and 5th percentiles) and durations (more than 1-2 consecutive days). Conditional logistic regression with distributed lag models was then applied to assess the accumulated effects of these warm-season cold spells on stroke risk over a lag period of 0-6 days, with adjustments for daily mean temperature.

RESULTS

Results confirmed that warm-season cold spells were significantly linked to an elevated risk of stroke with effects that could persist three days after exposure. The cumulative odds ratio (OR) estimates for the cold spells using the 2.5th percentile as air temperature threshold reached 1.29 (95% confidence interval (CI): 1.09-1.53) and 1.23 (95%CI: 1.05-1.44) for durations more than one and two days, respectively. Warm-season cold spells also had significant associations with both transient ischemic attacks and ischemic strokes. The stratified analysis showed that the elderly population (aged ≥ 65 years), females, and stroke cases characterized by minor symptoms demonstrated a significantly increased stroke risk of the effects of warm season cold spells.

CONCLUSIONS

This study presents strong evidence for an overlooked association between warm-season cold spells and an increased risk of stroke occurrence. These findings further highlight the multifaceted ways in which climate change can affect human health.

Impact of non optimal ambient temperature and temperature variation on the mortality of cardiovascular diseases: a research in Wuhu, China

Given the backdrop of global climate change, future temperatures are anticipated to exhibit increased variability and extremity, amplifying health risks and the burden of diseases, a matter of heightened concern. The aim of this research was to evaluate the mortality risk associated with cardiovascular diseases (CVD) due to suboptimal temperatures (daily mean temperature) and temperature variations (diurnal temperature range). Daily data spanning from 2014 to 2020 in Wuhu City were gathered, encompassing meteorological factors, environmental pollutants, and cardiovascular disease mortality information, involving 64,758 CVD deaths. Time-series analyses were conducted utilizing generalized additive models (GAM) and distributed lag nonlinear models (DLNM). Burden analysis was executed to estimate the percentage and count of daily CVD deaths linked to daily mean temperature (DMT) and diurnal temperature range (DTR). Lastly, a sensitivity analysis was conducted to assess the robustness of the model. A horizontal S-shaped relationship exists between DMT and CVD mortality rate, where both high and low temperatures exhibit adverse effects, with high temperatures demonstrating a more pronounced impact than low temperatures. An inverted J-shaped relationship exists between DTR and mortality, wherein extreme DTR elevates the risk of CVD mortality. Variations in exposure responses occur among populations with diverse characteristics. The main cause of death burden is moderately high temperature rather than extreme temperature. Importantly, non-extreme temperatures account for the majority of cardiovascular disease deaths, potentially exerting serious adverse effects on local public health.

Association between ambient temperatures and hospitalization costs for cardiovascular disease in Tianshui, Northwest China

As global climate change intensifies, the impact of ambient temperature on public health and healthcare systems has become increasingly significant. However, evidence on the association between temperature and health costs remains limited. This study investigates the association between ambient temperature and hospitalization costs (HCs) for cardiovascular diseases (CVD) in Tianshui, China, using data from 2016 to 2019. A distributed lag nonlinear model was employed to analyze the effects of daily average temperature on CVD-related HCs, self-payments (SPs), and Medicare payments (MPs), and to conduct cost attribution analyses across different temperature ranges. The results revealed a W-shaped relationship between temperature and HCs, SPs, and MPs. Compared to the reference temperature Minimum Hospitalization Temperature (MHT) of 0.3 °C, ambient temperature-attributable HCs totaled 7.47 million CNY over the study period, accounting for 3.65% (95% CI: 3.44-3.87%) of total costs, with an annual average of 1.87 million CNY. Low temperatures (below MHT) were associated with a higher risk of HCs, particularly at extreme low temperatures (1st percentile, -4 °C), which increased HCs by 35.4% (95% CI: 35.0-35.9%) compared to the reference temperature. However, the majority of HCs were attributable to high temperatures (above MHT), representing approximately 2.29% (95% CI: 2.15-2.44%) of total costs. Notably, extreme temperatures (both low and high) had a greater impact on SPs than on MPs, with 43.7% of SPs and 32.2% of MPs attributable to extreme temperatures. Additionally, men and younger individuals (age <65 years) bore the majority of HCs. These findings underscore the escalating health and economic burdens of climate change, particularly in terms of CVD hospitalization. Proactive and targeted strategies can mitigate public health risks, reduce financial burdens, and enhance the sustainability of public health insurance systems.

Association between ambient temperature and non-accidental mortality in Guiyang, China: A time-series analysis (2013-2023)

BACKGROUND

As climate change intensifies, ambient temperatures have become a global concern, leading to an increasing number of studies examining the impact of temperature on human health. Extreme weather events, including heatwaves and cold spells, are becoming more frequent and severe. Numerous studies have highlighted the positive correlation between non-optimal ambient temperatures and mortality. Understanding these impacts is crucial for developing targeted public health interventions and accurately predicting the future health burden associated with climate variability. This study aims to estimate the relative risks and mortality burden associated with temperature extremes over the past decade, focusing on the contributions of both heat and cold, as well as mild and extreme temperatures, and identifying vulnerable populations. By doing so, filling a regional research gap in Guiyang.

METHODS

We collected the daily weather and mortality data from 2013 to 2023. Descriptive analysis was conducted to characterize overall weather patterns and mortality trends during the study period. A quasi-Poisson regression with a distributed lag non-linear model (DLNM), incorporating a 21-day lag and controlling for trends, air pollutants, and the day of the week, was applied to estimate the cumulative relative risks of non-accidental mortality due to non-optimal and extreme temperatures. We calculated attributable fractions and attributable numbers for heat and cold (defined as temperatures above and below the daily mean temperature), mild temperatures (defined using cutoffs at the minimum mortality temperature, with mild heat ranging from the minimum mortality temperature to the 97.5th temperature percentile and mild cold ranging from the 2.5th temperature percentile to the minimum mortality temperature) and extreme temperatures (defined as temperatures below the 2.5th temperature percentile for extreme cold and above the 97.5th temperature percentile for extreme heat).

RESULTS

A total of 140,099 non-accidental deaths were included in the study.Temperature and mortality showed U-shaped associations, except for 0-64 years age group. For extreme low temperatures, the effects appeared in lag 2 to 4 days and lasted for approximately 18 days, peaking on lag day 5, yielding a cumulative relative risks (RRs) of 1.24% (95% CI 1.14% to 1.36%) for non-accidental mortality. For extreme high temperatures, the strongest effect was observed on the same day, with an RR of 1.18%(95% CI 1.03% to 1.35%). The attributable fraction of non-accidental mortality associated with non-optimal temperatures was 9.21% (95% eCI: 5.32% to 12.15%). The mortality burden from heat and cold was 5.55% (95% eCI: 2.04% to 8.59%) and 3.67% (95% eCI: 1.45% to 5.80%), respectively. Mild heat was responsible for the majority of the mortality burden.

CONCLUSION

Extreme low temperatures had higher cumulative relative risk and a prolonged effect compared to extreme high temperatures. The attributable fraction associated with non-optimal temperatures was highest for respiratory-related deaths. Mild heat was responsible for the majority of the mortality burden. Additionally, males and the individuals aged 65 years and above were particularly vulnerable populations.

Impact of rapid temperature fluctuations on acute stroke risk: a nationwide case-crossover study from 2001 to 2020

Background

Climate factors greatly affect cardiovascular health, with stroke ranking among serious global concerns. However, the impact of rapid temperature fluctuations on stroke risk remains underexplored. Given Taiwan's aging population and the intensifying effects of climate change, understanding influence of ambient temperatures on stroke risk is crucial for public health protection. This study aimed to explore the link between ambient temperature, sudden day-to-day temperature changes, and stroke onset in Taiwan, taking air pollutants into consideration.

Methods

We conducted a time-stratified case-crossover study from 2001 to 2020 using Distributed Lag Nonlinear Models (DLNM) within conditional logistic regression to examine lagged associations between temperature parameters and stroke risk. We analyzed associations separately for total stroke, ischemic stroke, and hemorrhagic stroke to identify potential differences in risk patterns, using odds ratios (ORs) relative to the temperature associated with the lowest stroke risk. Data from the National Health Insurance Research Database (NHIRD) identified the study population, including 1,100,074 first-time stroke emergency events and self-matched with 2,200,148 non-stroke onset dates as controls. The primary exposure assessments included daily temperatures (mean, maximum, and minimum) and temperature fluctuations (diurnal temperature range (DTR), sudden day-to-day temperature increases (TDI), and sudden day-to-day temperature decrease (TDD)), adjusted for air pollutants (PM2.5, O3, SO2, and NO2), and rainfall. Lag periods up to 13 days prior to the corresponding event or control days were used to examine the lag effect of stroke risk.

Findings

Through DLNM exposure-lag-response effect analysis after adjustment for PM2.5, O3, SO2, NO2, and rainfall, the study revealed that when TDI exceeded 6 °C, the risk of ischemic stroke more than doubled compared to the lowest risk temperature (OR: 2.173, 95% CI: 1.887, 2.501). The risk continued to rise until 9 °C, with a second peak observed when TDI exceeded 16 °C (OR: 2.096, 95% CI: 1.733, 2.535). Conversely, TDD exceeding 14 °C was linked to heightened hemorrhagic stroke risk (OR: 2.187, 95% CI: 2.055, 2.326). Additionally, daily maximum temperature exceeding 35 °C was associated with an increased stroke risk, primarily affecting ischemic stroke, while daily minimum temperature below 16 °C was strongly associated with a doubled risk of hemorrhagic stroke.

Interpretation

Our findings indicate that sudden day-to-day temperature increases and decreases are significant predictors of stroke onset. These results emphasize a noteworthy relationship between temperature and stroke risk over consecutive days, supporting interventions aimed at reducing stroke incidence.

Funding

This research was supported by the National Science and Technology Council (NSTC), Executive Yuan, Taiwan, grant No. NSTC-111-2119-M-865-002.

Forecasting heart failure: Seasonal alignment of heart failure outcomes in New York

BACKGROUND

Seasonal variations have been observed in heart failure (HF) hospitalization. Numerous explanatory mechanisms have been proposed, but no prior studies have examined potential contributors directly. Our objective was to identify specific factors that could contribute to seasonal variability using a large longitudinal dataset of HF hospitalizations.

METHODS

Hospital discharge data were obtained for all hospitals in the state of New York from 1994 to 2007. Records with a primary diagnosis of HF by the International Classification of Diseases-9 Clinical Modification (ICD-9-CM) code (428.xx and 425.xx) were included. Year and month of admission were used as predictors to evaluate outcomes of in-hospital mortality, population-adjusted daily rate of hospital admissions and length of stay (LOS) using univariable regression including a sinusoidal model to assess the seasonality of HF outcomes. Observations were then adjusted for multiple medical covariables as well as the average local monthly temperature and humidity at each hospital using data from the Global Historical Climate Network to identify potential modifiers of seasonal variability.

RESULTS

Among 949 907 records, the median age was 76 [inter-quartile range (IQR) 65-84 years old], and the cohort was 54% female (510 945 records). The population-adjusted rate of HF admissions per day increased by 1.1 admissions/day/year between 1994 and 2007, whereas in-hospital mortality and LOS decreased by -0.3%/year and -0.3 days/year, respectively (P < 0.001 for all). Seasonal trends were identified for daily HF admissions (February peak, P < 0.0001), mortality (January peak, P < 0.001) and LOS (January peak, P < 0.01). Cosinor analysis revealed significant periodicity for HF admission rate (amplitude = ±0.9 admissions/day/100 000 people, P < 0.001), in-hospital mortality (amplitude = ±0.47%, P < 0.001) and LOS (amplitude = ±0.23 days, P < 0.01). No other patient characteristics were significant modifiers of seasonality. Odds of mortality were highest in July rather than January when adjusted for average local temperature but not humidity.

CONCLUSIONS

Adverse outcomes in patients hospitalized with HF were significantly worse in the winter months even when adjusted for patient characteristics and concurrent acute diagnoses such as pneumonia. Local ambient temperature was the strongest modifier of the observed seasonality. Given the increasing frequency of extreme weather events, additional work to determine the mechanisms of this and other environmental risk factors is urgently needed.

The links between soil and water pollution and cardiovascular disease

Soil and water pollution represent significant threats to global health, ecosystems, and biodiversity. Healthy soils underpin terrestrial ecosystems, supporting food production, biodiversity, water retention, and carbon sequestration. However, soil degradation jeopardizes the health of 3.2 billion people, while over 2 billion live in water-stressed regions. Pollution of soil, air, and water is a leading environmental cause of disease, contributing to over 9 million premature deaths annually. Soil contamination stems from heavy metals, synthetic chemicals, pesticides, and plastics, driven by industrial activity, agriculture, and waste mismanagement. These pollutants induce oxidative stress, inflammation, and hormonal disruption, significantly increasing risks for non-communicable diseases (NCDs) such as cardiovascular disease (CVD). Emerging contaminants like micro- and nanoplastics amplify health risks through cellular damage, oxidative stress, and cardiovascular dysfunction. Urbanization and climate change exacerbate soil degradation through deforestation, overfertilization, and pollution, further threatening ecosystem sustainability and human health. Mitigation efforts, such as reducing chemical exposure, adopting sustainable land-use practices, and advancing urban planning, have shown promise in lowering pollution-related health impacts. Public health initiatives, stricter pollution controls, and lifestyle interventions, including antioxidant-rich diets, can also mitigate risks. Pollution remains preventable, as demonstrated by high-income nations implementing cost-effective solutions. Policies like the European Commission's Zero-Pollution Vision aim to reduce pollution to safe levels by 2050, promoting sustainable ecosystems and public health. Addressing soil pollution is critical to combating the global burden of NCDs, particularly CVDs, and fostering a healthier environment for future generations.

Imperatives and co-benefits of research into climate change and neurological disease

Evidence suggests that anthropogenic climate change is accelerating and is affecting human health globally. Despite urgent calls to address health effects in the context of the additional challenges of environmental degradation, biodiversity loss and ageing populations, the effects of climate change on specific health conditions are still poorly understood. Neurological diseases contribute substantially to the global burden of disease, and the possible direct and indirect consequences of climate change for people with these conditions are a cause for concern. Unaccustomed temperature extremes can impair the systems of resilience of the brain, thereby exacerbating or increasing susceptibility to neurological disease. In this Perspective, we explore how changing weather patterns resulting from climate change affect sleep - an essential restorative human brain activity, the quality of which is important for people with neurological diseases. We also consider the pervasive and complex influences of climate change on two common neurological conditions: stroke and epilepsy. We highlight the urgent need for research into the mechanisms underlying the effects of climate change on the brain in health and disease. We also discuss how neurologists can respond constructively to the climate crisis by raising awareness and promoting mitigation measures and research - actions that will bring widespread co-benefits.

Acute Impact of Nonoptimal Ambient Temperatures on Plasma Levels of 3000 Proteins in Chinese Adults

Nonoptimal ambient temperatures (i.e., cold and heat) are leading environmental determinants of major diseases worldwide, but the underlying pathological mechanisms are still poorly understood. We used distributed-lag nonlinear models to examine the associations of cold (5th percentile: -2.1 °C) and heat (95th percentile: 29.5 °C) with 2923 plasma proteins in 3926 adults from 10 areas across China. Overall, 949 proteins were significantly (5% false discovery rate) associated with ambient temperature, including 387 (216/171 down/upregulated) with cold, 770 (656/114 down/upregulated) with heat, and 208 with both cold and heat. Above the median reference temperature (17.7 °C), the associations were largely linear, while below it, they were nonlinear with attenuation below 5 °C, potentially reflecting mediation by heating. Among the 949 proteins, >80% were also associated with systolic blood pressure and incident ischemic heart disease risk and enriched in relevant pathological pathways (e.g., inflammation, immunity, and platelet aggregation). Our study provided a novel atlas of plasma proteins associated with nonoptimal temperatures in Chinese adults.

Self-Care Behaviors of Patients With Heart Failure in Thailand: A qualitative descriptive study

INTRODUCTION

This study explored people's experiences of living with heart failure and their understanding of self-management and difficulties faced when making lifestyle changes in the context of high-salt food preferences and a subtropical climate.

METHODS

This qualitative descriptive study was conducted with 20 Thai individuals with heart failure. Data were analyzed using thematic content analysis.

RESULTS

Two overarching themes were: (a) adapting long-established dietary and lifestyle behaviors is challenging in the context of limited knowledge of heart failure, cultural food preparation practices and a subtropical climate and (b) personal values, attitudes, and preferences have primacy over dietary and fluid restrictions.

DISCUSSION

In Thailand, strong cultural preferences for high salt, preprepared street foods contribute to repeated admissions for decompensated heart failure. Community-based models of care are urgently needed that support effective chronic heart failure management, with solutions that consider local needs, climate and cultural factors.

The effect of heatwave and cold spell on cardiovascular disease mortality in central China, 2018-2022

Heatwave and cold spell have been linked to cardiovascular disease (CVD) mortality. However, due to the varying definitions of heatwave and cold spell, their impacts on CVD mortality are inconsistent.

METHODS

A time series study in Hunan province, central of China, from 2018 to 2022, was conducted to test the relationship between heatwave, cold spell and CVD mortality. According to different percentiles of daily mean temperatures and exposure duration, we built 9 kind of definitions for heatwave and cold spell. Distributed lag non-linear model was used to analyze the associations between heatwave, cold spell and CVD mortality, and the attributable fraction (AF) were estimated.

RESULTS

The relative risks of CVD mortality associated with heatwave and cold spell varied depending on the definitions, ranging from 1.154 (95% CI: 1.148-1.160) to 1.229 (95% CI: 1.215-1.243) for heatwaves, and from 1.196 (95% CI: 1.192-1.201) to 1.290 (95% CI: 1.282-1.297) for cold spells. Under the definition of 95th percentile with ≥ 4-d duration (P95_4d), the total AF of CVD mortality attributable to heatwave was the largest at 8.43 (95% CI: 7.92-8.94). For the definition of 5th percentile with ≥ 3-d duration (P5_3d), the total AF attributable to cold spell was the largest at 12.96 (95% CI: 12.64-13.28). For heatwave and cold spell, higher CVD mortality risks were observed in females and the elderly over 75 years than males and young people.

DISCUSSION

We found that both heatwave and cold spell could increase the mortality risk of CVD. The results highlight the importance of implementing warning systems for extreme temperature.

Cold-related Mortality in US State and Private Prisons: A Case-Crossover Analysis

BACKGROUND

Cold temperatures are associated with increased risk for cardiovascular and respiratory disease mortality. Due to limited temperature regulation in prisons, incarcerated populations may be particularly vulnerable to cold-related mortality.

METHODS

We analyzed mortality data in US prisons from 2001 to 2019. Using a case-crossover approach, we estimated the association of a 10 °F decrease in cold temperature and extreme cold (days below the 10th percentile) with the risk of total mortality and deaths from heart disease, respiratory disease, and suicide. We assessed effect modification by personal, facility, and regional characteristics.

RESULTS

There were 18,578 deaths during cold months. The majority were male (96%) and housed in a state-operated prison (96%). We found a delayed association with mortality peaking 3 days after and remaining positive until 6 days after cold exposure. A 10 °F decrease in temperature averaged over 6 days was associated with a 5.1% (95% confidence interval [CI]: 2.1%, 8.0%) increase in total mortality. The 10-day cumulative effect of an extreme cold day was associated with an 11% (95% CI: 2.2%, 20%) increase in total mortality and a 55% (95% CI: 11%, 114%) increase in suicides. We found the greatest increase in total mortality for prisons built before 1980, located in the South or West, and operating as a dedicated medical facility.

CONCLUSIONS

Cold temperatures were associated with an increased risk of mortality in prisons, with marked increases in suicides. This study contributes to the growing evidence that the physical environment of prisons affects the health of the incarcerated population.

Effect of burn injury size on cardiovascular responses to exercise in the heat

We tested the hypothesis that due to well recognized thermoregulatory impairments, resulting in greater thermal strain, adults with well healed burn injuries will have heightened cardiovascular responses to exercise in the heat. Adults with burn injuries covering 20-40% body surface area (n = 10), > 40% body surface area (n = 11), and non-burned controls (n = 10) performed 1 h of treadmill walking at a fixed rate of metabolic heat production (~ 4.5 w/kg) in the heat (39 °C, 40% relative humidity). Core temperature, heart rate, stroke volume, and blood pressure were obtained at rest and during exercise. The increase in core temperature was 0.89 ± 0.40 °C for control, 0.92 ± 0.43 °C for 20-40%, and 1.30 ± 0.58 °C for > 40% (interaction: p = .08). Ending heart rate was greater in > 40% compared to control (142 ± 27 vs 118 ± 9 bpm; p = .03), however there was no difference between 20-40% and control (128 ± 24 vs 118 ± 9 bpm; p = .44). Ending rate pressure product was higher in the > 40% compared to control (21,326 ± 4327 vs 15,971 ± 2156 mmHg*bpm; p = .007), however there was no difference between 20-40% and control (18,698 ± 3741 vs 15,971 ± 2156 mmHg*bpm; p = .16). At 45-min into exercise, cardiac minute work was higher in the > 40% compared to control (577 ± 102 vs 467 ± 63 L/min*mmHg/m2; p = .02), but there was no difference between 20-40% and control (513 ± 82 vs 467 ± 63 L/min*mmHg/m2; p = .36). These findings show that well-healed burn survivors with large burn injuries, such as those covering > 40% of total body surface area, have increased cardiovascular strain during exercise heat stress.

Effect modifiers of the temperature-mortality association for general and older adults population of Brazil's metropolitan areas

Ambient temperature effect on mortality varies between places and populations, suggesting the existence of effect modifiers for this association. This study analyzes the influence of geographic, urban, and socioeconomic factors on the ambient temperature effect on non-accidental mortality in the general and older adults population of Brazilian metropolitan areas, and on that associated with circulatory, respiratory, and other mortality in older adults. Effects of this association were estimated for each group in 42 locations using a generalized additive model combined with the nonlinear distributed lag model. A meta-analysis was then performed to estimate the effects at the national and regional levels. Meta-regression determined the influence of effect modifiers. Estimated relative risks of the temperature-mortality association varied between locations in the Brazilian territory. Heat effects on non-accidental mortality at the national level were 1.09 (95%CI: 1.04-1.15) and 1.13 (95%CI: 1.07-1.20) for the General and Older Adult groups, respectively. Cold effects were 1.26 (95%CI: 1.21-1.32) and 1.30 (95%CI: 1.24-1.36) for the General and Older Adult groups, respectively. We observed a greater effect of cold than heat in both groups. For all causes of death, effects of heat and cold were greater in the Southeast and South Brazil. Amplitude of the mean temperature was the factor that best explained the heterogeneity between locations, followed by latitude, income and schooling. Hence, implementing adaptive measures to reduce the ambient temperature effects on mortality depends on the profile of each location.

Global, Regional, and National Burden of Ischemic Heart Disease Attributable to 25 Risk Factors and Their Summary Exposure Value Across 204 Countries With Different Socio-Demographic Index Levels, 1990-2021: A Systematic Fixed-Effects Analysis and Comparative Study

Background

A systematic relational assessment of the global, regional, and national Ischemic heart disease (IHD) burden and its attributable risk factors is essential for developing more targeted prevention and intervention strategies.

Methods

The GBD 2021 comparative risk assessment framework was employed to evaluate stroke burden attributable to environmental, behavioral, metabolic, and dietary risk factors, and a total of 25 risk factors were included. Specifically, we used the joinpoint regression model, decomposition analysis, and systematic fixed-effects analysis to reveal the global, regional, and national burden of IHD attributable to these 25 risk factors and their exposure value across 204 countries and territories with different socio-demographic index (SDI) levels from different perspectives.

Results

Joinpoint regression revealed similar trends in summary exposure value (SEV) and attributable burdens for 25 IHD risk factors. From 1990 to 2021, SEV rankings increased for 12/25 risk factors, decreased for 10/25, and remained unchanged for 3/25. Decomposition analysis indicated that from 1990 to 2021, low SDI countries experienced the most significant increase in IHD burden attributable to 25 risk factors due to population growth, while upper-middle and high SDI countries were most affected by population aging, and high SDI countries demonstrated the greatest reduction in IHD burden attributed to epidemiological changes. Panel data analysis elucidated the impact of SEV, SDI, and quality-of-care index (QCI) on attributable IHD burden.

Conclusion

This study emphasizing the critical role of risk factor control. Tailored interventions and exploration of country-specific factors are crucial for effectively reducing the global IHD burden.

Climate change and cardiovascular risk

PURPOSE OF REVIEW

This review explores the complex relationship between climate change and cardiovascular health. It examines the mechanisms through which climate change impacts cardiovascular risk, highlights recent findings on regional trends, and discusses mitigation strategies.

RECENT FINDINGS

Climate change significantly contributes to cardiovascular morbidity and mortality through mechanisms such as temperature extremes, air pollution, and food insecurity. Heatwaves increase risks of dehydration, electrolyte imbalance, and acute cardiovascular events, while cold spells exacerbate myocardial stress and pollution-related cardiovascular risks. Air pollution, including fine particulate matter (PM2.5), induces systemic inflammation, endothelial dysfunction, and atherosclerosis. Emerging data highlight regional variations, with urbanization exacerbating risks in Asia-Pacific and Middle Eastern populations, while extreme heat and cold challenge resilience in Europe and Latin America. Studies also link socioeconomic stress from climate-induced displacement and resource shortages to chronic cardiovascular conditions. Notably, urban greening and air quality regulations demonstrate potential for reducing cardiovascular risks.

SUMMARY

Climate change amplifies cardiovascular risks through diverse mechanisms, disproportionately affecting vulnerable populations. Targeted strategies, including public health campaigns, sustainable urban planning, and technological innovations, can mitigate these risks. Advances in generative artificial intelligence and big data analytics offer opportunities to tailor interventions and enhance predictive modeling. A multidisciplinary approach integrating public health, environmental science, and clinical expertise is critical to addressing these challenges. Urgent action is required to mitigate the long-term cardiovascular impacts of climate change and foster resilient health systems globally.

Associations of heatwaves and their characteristics with ischaemic stroke hospital admissions

Ischaemic stroke (IS) has a heavy disease burden. Although epidemiological research has suggested that heatwaves are associated with cardiovascular disease, there is a lack of empirical evidence for a correlation between heatwaves and IS. The China Meteorological Administration defines a heatwave as a wave lasting ≥ 3 days, with a maximum temperature of ≥ 35℃. We collected data on daily meteorological conditions, air pollution, and IS admissions in Hunan Province from 2018 to 2019. A generalized additive model and distributed lag nonlinear model were used to determine the associations between heatwaves and IS admissions. We analysed 329,876 admitted patients with IS in Hunan Province from 2018 to 2019. The main effect of heatwaves was that they significantly increased the risk of hospitalization for IS. The single-day lag maximum risk occurred at a daily average temperature of 30.88℃ (RR = 1.05, 95% CI: 1.04-1.06) and at a daily maximum temperature of 35.82℃ (RR = 1.05, 95% CI: 1.03-1.06). The use of the 5th and subsequent days of a heatwave as a reference showed that the 1st-2nd days (RR = 1.07, 95% CI: 1.02-1.12) and the 3rd-4th days (RR = 1.68, 95% CI: 1.03-1.10) of the heatwave increased the risk of hospitalization for IS. Compared with the third and subsequent heatwaves, the first (RR = 1.27, 95% CI: 1.19-1.35) and second (RR = 1.24, 95% CI: 1.16-1.32) heatwaves had greater impacts on the risk of hospitalization for IS. The risk of IS hospitalization was also exacerbated by high relative humidity (RR = 1.25, 95% CI: 1.16-1.35) and a low diurnal temperature range (RR = 1.08, 95% CI: 1.02-1.14) during the heatwave period. In our study, the main effects of heatwaves increased the risk of IS hospitalization. The effects varied according to the day of the heatwave, the timing of the heatwave, the DTR during the heatwave, and the humidity during the heatwave. This evidence has significant implications for the strategic planning of public health interventions to mitigate adverse health outcomes associated with heatwaves.

Characterisation of cardiovascular disease (CVD) incidence and machine learning risk prediction in middle-aged and elderly populations: data from the China health and retirement longitudinal study (CHARLS)

BACKGROUND

Due to the ageing population and evolving lifestyles occurring in China, middle-aged and elderly populations have become high-risk groups for cardiovascular disease (CVD). The aim of this study was to analyse the incidence characteristics of CVD in these populations and develop a prediction model by using data from the China Health and Retirement Longitudinal Study (CHARLS).

METHODS

We used follow-up data from the CHARLS to analyse CVD incidence in the Chinese middle-aged and elderly population over a time span of 9 years. Five machine learning (ML) algorithms were employed for risk prediction. Data preprocessing included missing value imputation via random forest. Feature selection was performed using the Least Absolute Shrinkage and Selection Operator (Lasso CV) method with cross-validation prior to model training. The application of the synthetic minority over-sampling technique (SMOTE) to address class imbalance. Model performance was evaluated via analyses including the area under the ROC curve (AUC), precision, recall, F1 score, and SHAP plots for interpretability.

RESULTS

In accordance with the exclusion criteria, 12,580, 12,061, 11,545, and 11,619 participants were enrolled in four follow-up rounds. The cumulative incidence (CI) of CVD at 2, 4, 7, and 9 years was 2.846%, 8.971%, 17.869% and 20.518%,, respectively. Significant differences in CVD incidence were observed across gender, age, ethnicity, and region, with higher rates observed in females and in the northeast region. Ultimately, 8,080 participants and 24 features were analysed for CVD risk prediction. Five ML models were built based on these features. Although the LGB model achieves an AUC of 0.818, indicating strong overall performance, its F1 score and recall rate are relatively low, at 0.509 and 43.1%, respectively. Shapley additive explanations (SHAP) analyses revealed the importance of key features, such as night sleep duration, TG levels, and waist circumference, in predicting outcomes, and highlighted the nonlinear relationships between these features and CVD risk.

CONCLUSIONS

Gender, age, ethnicity, and region are significant factors influencing CVD incidence. Although the LGB model demonstrates good overall performance, its low F1 score and recall rate reveal limitations in identifying high-risk cardiovascular disease patients.

Ambient temperature and dengue hospitalization in Brazil: A 10-year period case time series analysis

Background

Dengue has an increased worldwide epidemic potential with the global rising temperature due to climate change. Heat and rainfall are known to influence seasonal patterns of dengue transmission over the course of weeks to months. However, there is a gap in knowledge about the short-term effect of heat on dengue severity. We aimed to quantify the effect of ambient temperature on dengue hospitalization risk in Brazil.

Methods

Daily dengue hospitalization counts and average daily ambient temperature from 2010 to 2019 were analyzed from Brazil. We applied the case time series design combined with a distributed lag nonlinear model framework to estimate relative risk (RR) estimates for dose-response and lag-response structures for the association of temperature and dengue hospitalization. We estimate the overall dengue hospitalization RR for the whole country as well as for each of the five macroregions.

Results

A total of 579,703 hospital admissions due to dengue occurred between 2010 and 2019. We observed a positive association between high temperatures and a high risk of hospitalization across the country. Under extreme heat (95th percentile of temperature), the RR was 3.47 (95% confidence interval: 2.88, 4.19) compared with minimum hospitalization risk. This association was mainly driven by an immediate effect of heat (lag 0) and was similar for the Northeast, Center-West, Southeast, and South regions, but unclear for the North. The risk was of greater magnitude among females and those aged ≥65 years.

Conclusion

Short-term high temperatures are associated with an increase in the risk of hospitalization by dengue.

Cold temperature-related attributable risk for emergency circulatory hospitalizations, length of stay, and healthcare costs in Hong Kong

BACKGROUND

The association of ambient temperature with the length of hospital stays and healthcare costs has not been well-explored. We aimed to examine the association of temperature with emergency hospital admission (EHA) count and length of stay (LOS) for total and cause-specific circulatory diseases and evaluate the temperature-related attributable risk and healthcare costs.

METHODS

This ecologic time series analysis linked the daily circulatory EHA count and LOS from the Hong Kong Hospital Authority with the environmental exposures from the fixed monitoring stations from 2004 to 2019. The generalized linear quasi-Poisson model integrated with a distributed lag nonlinear model was applied to examine ambient temperatures' relative and attributable risks on EHA counts and LOS while adjusting the time-varying confounders. Temperature-related healthcare costs were evaluated based on the estimated attributable number (AN) and charges per attendance or bed day.

RESULTS

Among 1276,632 EHAs and 7621,232 bed days of LOS, significant associations of cold temperatures with both EHA counts and LOS for total and cause-specific circulatory diseases were found. The temperature-related attributable fraction (AF) was estimated as 7.98 % (95 % CI: 5.24-10.58 %) for EHA count and 13.09 % (6.80-18.28 %) for LOS for total circulatory diseases. The cold temperature defined as the lower quartile of the ambient temperature range explained more than half of the temperature-related attributable risk and healthcare costs.

CONCLUSION

Cold weather can lead to adverse health outcomes, with considerable pressure on the healthcare system. Longer LOS-associated higher healthcare costs in colder weather may have implications for developing targeted preventions and hospital service planning.

Association of Cardiovascular Disease Mortality and Ambient Temperature Variation in Shanghai, China: Beyond Air Quality Index PM2.5

Evidence from megacity registry data regarding the independent association between ambient temperature and cardiovascular disease (CVD) mortality, after accounting for Particulate Matter 2.5 (PM2.5), remains scarce. In this study, we collected 308,116 CVD mortality cases in Shanghai from 2015 to 2020. The distributed lag non-linear model (DLNM) was utilized. The daily PM2.5 concentration was transformed using a natural spline (ns) function and integrated into the model for adjustment. The DLNM analysis revealed that the exposure-response curve between daily temperature and CVD mortality approximated an inverted "J" shape, consistent for both women and men. The minimum mortality temperature (MMT) for total CVD mortality was 25 °C, with an MMT of 26 °C for females and 24 °C for males. The highest relative risk (RR) of CVD mortality was 2.424 [95% confidence interval (95% CI): 2.035, 2.887] at the lowest temperature of -6.1 °C, with 2.244 (95% CI: 1.787, 2.818) for female and 2.642 (95% CI: 2.100, 3.326) for male. High temperatures exert acute and short-term effects, with the peak risk occurring on the day of exposure. In contrast, the risk from low temperature peaks on day 3 of the lag time and subsequently declines until days 16-21. This study offers evidence-based support for the prevention of temperature-induced CVD mortality.

An Overview of Climate Changes and Its Effects on Health: From Mechanisms to One Health

Human activities, primarily the burning of fossil fuels, widespread deforestation, soil erosion or machine-intensive farming methods, manufacturing, food processing, mining, construction, and the iron, cement, steel, and chemicals industries, have been the main drivers of the observed increase in Earth's average surface temperature and climate change. Rising global temperatures, extreme weather events, ecosystems disruption, agricultural impacts, water scarcity, problems in access to good quality water, food and housing, and profound environmental disruptions such as biodiversity loss and extreme pollution are expected to steeply increase the prevalence and severity of acute and chronic diseases. Its long-term effects cannot be adequately predicted or mitigated without a comprehensive understanding of the adaptive ecosystems. Studying the complex interaction between environmental aggressors and the resilient adaptive responses requires the exposomic and the One Health approaches. The problem is broad and affects the whole ecosystem, plants, pets, and animals in addition to humans. The central role of the epithelial barrier, microbiome, and diet as key pillars for an adaptive tolerogenic immune response should be explored for increasing resilience at the individual level. A radical change in mindset worldwide, with sustainable solutions and adaptive strategies and climate resilience and health equity policies at their center, should be achieved quickly through increased awareness based on solid scientific data.

Joint exposure to multiple air pollutants and residual cardiovascular risk in hypertension

BACKGROUND

Despite the widespread availability of antihypertensive medications, residual cardiovascular risk of hypertension remained high. Limited studies have investigated the link between air pollution, particularly joint exposure to multiple air pollutants, with residual cardiovascular risk of hypertension.

METHODS

1981 hypertensive patients (≥ 18 years) from an ongoing longitudinal cohort in China, were enrolled between 2013 and 2019. Using high-quality datasets from China, the ground-level air pollutants concentrations, including PM2.5, PM2.5-10, SO2, O3, CO and NO2, at each participant's residence were calculated. The relationships between individual and multiple air pollutants with the residual cardiovascular risk were assessed by Cox proportional hazards models, air pollution score analyses and Bayesian Kernel Machine Regression model.

RESULTS

Over an average follow-up period of 2.24 years (SD, 1.25), 706 hypertensive patients developed cardiovascular disease. In the single-pollutant analysis, higher concentrations of PM2.5, PM2.5-10, SO2 and CO were linked to increased residual cardiovascular risk. The air pollution score analyses and Bayesian kernel machine regression suggested that combined exposure to multiple air pollutants had a positive association with the residual cardiovascular risk, and NO2 played a dominant role. With higher NO2 concentrations, the hazard ratio of individual pollutants to residual cardiovascular risk increased.

CONCLUSIONS

Prolonged exposure to a mixture of various air pollutants is linked to elevated residual cardiovascular risk in individuals with hypertension. Apart from taking antihypertensive medication and adopting healthy lifestyle behaviors, hypertensive patients should lower air pollutant exposure to decrease residual cardiovascular risk.

Comorbidities, Tobacco Exposure, and Geography: Added Risk Factors of Heat and Cold Wave-related Mortality among U.S. Veterans with Chronic Obstructive Pulmonary Disease

Rationale: Understanding the health risks associated with extreme weather events is needed to inform policies to protect vulnerable populations. Objectives: To estimate heat and cold wave-related mortality risks in a cohort of veteran patients with chronic obstructive pulmonary disease (COPD) and explore disparities among strata of comorbidities, tobacco exposure, and urbanicity. Methods: We designed a time-stratified case-crossover study among deceased patients with COPD between 2016 and 2021 in the Veterans Health Administration system. Distributed lag models with conditional logistic regression estimated incidence rate ratios of heat and cold wave-associated mortality risk from lag days 0 to 3 for heatwaves and lag days 0 to 7 for cold waves. Attributable risks (ARs) per 100,000 patients were also calculated. Results: Of the 377,545 deceased patients with COPD, the largest heatwave-related mortality risk was in patients with COPD and asthma (AR, 14,016; 95% confidence interval [CI], -326, 30,706) across lag days 0 to 3. The largest cold wave-related mortality burden was in patients with COPD with no other reported comorbidities (AR, 1,704; 95% CI, 759, 2,686) across lag days 0 to 7. Patients residing in urban settings had the greatest heatwave-related (AR, 1,062; 95% CI, 576, 1,559) and cold wave-related (AR, 1,261; 95% CI, 440, 2,105) mortality risk (across lag days 0 to 1 and 0 to 7, respectively). There were no differences in mortality risk by tobacco exposure. Conclusions: Our findings show that individuals with COPD are susceptible to heat and cold waves. This information can inform clinical practice and public health policy about the mortality risk vulnerable populations experience with respect to extreme weather conditions. Furthermore, our results may be used in the development and refinement of future extreme weather warning systems designed for public health purposes.

Society for Cardiovascular Magnetic Resonance recommendations toward environmentally sustainable cardiovascular magnetic resonance

Delivery of health care, including medical imaging, generates substantial global greenhouse gas emissions. The cardiovascular magnetic resonance (CMR) community has an opportunity to decrease our carbon footprint, mitigate the effects of the climate crisis, and develop resiliency to current and future impacts of climate change. The goal of this document is to review and recommend actions and strategies to allow for CMR operation with improved sustainability, including efficient CMR protocols and CMR imaging workflow strategies for reducing greenhouse gas emissions, energy, and waste, and to decrease reliance on finite resources, including helium and waterbody contamination by gadolinium-based contrast agents. The article also highlights the potential of artificial intelligence and new hardware concepts, such as low-helium and low-field CMR, in achieving these aims. Specific actions include powering down magnetic resonance imaging scanners overnight and when not in use, reducing low-value CMR, and implementing efficient, non-contrast, and abbreviated CMR protocols when feasible. Data on estimated energy and greenhouse gas savings are provided where it is available, and areas of future research are highlighted.

Environmental Pollutants as Emerging Concerns for Cardiac Diseases: A Review on Their Impacts on Cardiac Health

Comorbidities related to cardiovascular disease (CVD) and environmental pollution have emerged as serious concerns. The exposome concept underscores the cumulative impact of environmental factors, including climate change, air pollution, chemicals like PFAS, and heavy metals, on cardiovascular health. Chronic exposure to these pollutants contributes to inflammation, oxidative stress, and endothelial dysfunction, further exacerbating the global burden of CVDs. Specifically, carbon monoxide (CO), ozone, particulate matter (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), heavy metals, pesticides, and micro- and nanoplastics have been implicated in cardiovascular morbidity and mortality through various mechanisms. PM2.5 exposure leads to inflammation and metabolic disruptions. Ozone and CO exposure induce oxidative stress and vascular dysfunction. NO2 exposure contributes to cardiac remodeling and acute cardiovascular events, and sulfur dioxide and heavy metals exacerbate oxidative stress and cellular damage. Pesticides and microplastics pose emerging risks linked to inflammation and cardiovascular tissue damage. Monitoring and risk assessment play a crucial role in identifying vulnerable populations and assessing pollutant impacts, considering factors like age, gender, socioeconomic status, and lifestyle disorders. This review explores the impact of cardiovascular disease, discussing risk-assessment methods, intervention strategies, and the challenges clinicians face in addressing pollutant-induced cardiovascular diseases. It calls for stronger regulatory policies, public health interventions, and green urban planning.

Associations between anthropogenic heat emissions and serum lipids among adults in northeastern China

Few epidemiological studies have investigated associations between anthropogenic heat emissions (AE) and serum lipids. We recruited 15,477 adults from 33 communities in northeastern China in 2009. We estimated AE flux by using data on energy consumption and socio-economic statistics covering building, transportation, industry, and human metabolism. We assessed the associations between AE and blood lipids and dyslipidemia prevalence using the restricted cubic spline models. The regression coefficients (β) and the 95% CI of total cholesterol for the 75th and 95th percentiles of the exposure were 0.23 mmol/L (95% CI: 0.15, 0.30) and 0.25 mmol/L (95% CI: 0.18, 0.32). We also found AE was positively associated with dyslipidemia. Participants who were female or who had low incomes exhibited more pronounced associations. Our research showed that exposure to AE was significantly associated with serum lipids. These novel, valuable findings are useful to inform policymakers to estimate the risks to human health from anthropogenic heat.

Risk of hemorrhagic fever with renal syndrome associated with meteorological factors in diverse epidemic regions: a nationwide longitudinal study in China

BACKGROUND

Hemorrhagic fever with renal syndrome (HFRS) is a climate-sensitive zoonotic disease that poses a significant public health burden worldwide. While previous studies have established associations between meteorological factors and HFRS incidence, there remains a critical knowledge gap regarding the heterogeneity of these effects across diverse epidemic regions. Addressing this gap is essential for developing region-specific prevention and control strategies. This study conducted a national investigation to examine the associations between meteorological factors and HFRS in three distinct epidemic regions.

METHODS

We collected daily meteorological data (temperature and relative humidity) and HFRS incidence cases of 285 cities in China from the Resource and Environment Science and Data Center and the Chinese National Notifiable Infectious Disease Reporting Information System from 2005-2022. Study locations were stratified into three distinct epidemic categories (Rattus-dominant, Apodemus-dominant, and mixed) based on the seasonality of peak incidence. The associations between meteorological variables and HFRS incidence were investigated using a time-stratified case-crossover design combined with distributed lag nonlinear modeling for each epidemic category.

RESULTS

The exposure-response relationships between meteorological factors and HFRS incidence revealed significant heterogeneity across epidemic regions, as evidenced by Cochran's Q test for temperature (Q = 324.40, P < 0.01) and relative humidity (Q = 30.57, P < 0.01). The optimal daily average temperature for HFRS transmission in Rattus-dominant epidemic regions (- 6.6 °C), characterized by spring epidemics, was lower than that observed in Apodemus-dominant epidemic regions (13.7 °C), where primary cases occurred during autumn and winter months. Furthermore, the association between relative humidity and HFRS incidence exhibited as a monotonic negative correlation in Rattus-dominant regions, while Apodemus-dominant regions showed a nonlinear, inverted U-shaped association.

CONCLUSIONS

This study highlights the heterogeneous effects of meteorological factors on HFRS incidence across different epidemic regions. Targeted preventive measures should be taken during cold and dry spring days in Rattus-dominant regions, and during warm and moderately humid winter days in Apodemus-dominant regions. In mixed epidemic regions, both scenarios require attention. These findings provide novel scientific evidence for the formulation and implementation of region-specific HFRS prevention policies.

Exposure to high-temperature and high-humidity environments associated with cardiovascular mortality

Aging populations are susceptible to climate change due to physiological factors and comorbidities. Most relevant studies reported the effect of temperature on cardiovascular disease (CVD)-related mortality in aging populations. However, the combined effects of temperature and humidity on CVD-related mortality remain unclear. Here we used the Global Burden of Disease (GBD) database to analyze CVD burden and its impact on the incidence of CVD in individuals exposed to high-temperature and high-humidity (HTH) environments. The prospective China Health and Retirement Longitudinal Study (CHARLS) cohort was used to further analyze the relationship between exposure to HTH environments and CVD mortality in middle-aged and elderly individuals. We found significant positive correlations between the estimated annual percentage change of CVD and age-standardized rate, wet bulb globe temperature, and Humidex worldwide. In the CHARLS, a higher CVD mortality rate was significantly associated with exposure to HTH environments (P < 0.01). Long-term HTH environment exposure increased the risk of an abnormal low-density lipoprotein cholesterol (LDL-C) level (hazard ratio [HR], 1.30-2.44) and abnormal total cholesterol (TC) level (HR, 1.21-2.13), but the impact on high-density lipoprotein cholesterol (HDL-C) level was unclear. The mortality risks of long-term exposure to HTH environments were increased for middle-aged and elderly individuals with abnormal LDL-C (HR = 0.84-3.57) and TC (HR = 0.78-2.41) levels. These findings suggest that exacerbated dyslipidemia caused by long-term HTH environment exposure may be a key risk factor for CVD-related mortality in middle-aged and elderly individuals and suggest research directions into the effects of HTH environments on human health.

Associations of short-term exposure to air pollution with risk of pulmonary space-occupying lesions morbidity based on a time-series study

BACKGROUND

Pulmonary space-occupying lesions are typical chronic pulmonary diseases that contribute significantly to healthcare resource use and impose a large disease burden in China. A time-series ecological trend study was conducted to investigate the associations between environmental factors and hospitalizations for pulmonary space-occupying lesions in North of China from 2014 to 2022.

METHODS

The DLNM was used to quantify the association of environmental factors with lung cancer admissions. The heating-, age-, gender-, malignancy-specific effects were further estimated to identify the susceptible groups.

RESULTS

During the study period, fluctuations in air pollutants and climate conditions closely mirrored changes in hospitalizations for pulmonary space-occupying lesions. Totally, the distributed lag surface showed clear positive associations between pulmonary tumor hospitalization and PM2.5 (RRlag30: 1.000912; 95%CI: 1.000076, 1.00175), PM10 (RRlag30: 1.002246; 95%CI: 1.000474, 1.004021), SO2 (RRlag30: 1.002714; 95%CI: 1.001071, 1.004414), CO (RRlag30: 1.002231; 95%CI: 1.000592, 1.003873). Additionally, the associations between air pollutants and hospitalizations for pulmonary space-occupying lesions were significantly stronger during the heating season. Population aged 65 or older, females and those diagnosed with malignancies were more vulnerable for the risk of pulmonary space-occupying lesions diseases due to air pollution exposure.

CONCLUSIONS

The present study illustrated risk and burden for pulmonary space-occupying lesions hospitalization associated with air pollution, especially among population aged ≥ 65, or female.

Burden trends and future predictions for hypertensive heart disease attributable to non-optimal temperatures in the older adults amidst climate change, 1990-2021

Background

Hypertensive heart disease (HHD) is a significant form of end-organ damage caused by hypertension, with profound impacts on global health and quality of life. Temperature anomalies driven by climate change, particularly extremes of heat and cold, are increasingly recognized as major contributors to the cardiovascular disease burden, notably impacting HHD. However, the specific spatiotemporal trends and gender-based differences in the burden of non-optimal temperatures on older adults HHD patients remain insufficiently explored. This study aims to evaluate the regional, gender-specific trends in the burden of HHD attributed to non-optimal temperatures among the older adults from 1990 to 2021, and to project future trends in HHD burden under climate-induced temperature anomalies from 2022 to 2050.

Methods

Data were sourced from the Global Burden of Disease Study (GBD 2021), which provides estimates of mortality and disability-adjusted life years (DALYs) at global, regional, and national levels. Age-standardized rates (ASR) and estimated annual percentage changes (EAPC) were analyzed. Future burden projections were modeled using age-period-cohort (APC) and Bayesian APC models to assess temperature impact by gender and age differences. Data analysis was conducted using R and STATA, examining the variations in temperature effects by gender and age.

Results

Between 1990 and 2021, cold-related HHD burden among the older adults significantly exceeded that of heat-related burden. However, heat-related HHD burden demonstrated a marked upward trend, projected to continue rising over the next two decades, particularly in low-income and tropical regions. Gender-specific analysis revealed that cold-related HHD burden was more pronounced in women, while heat-related burden was notably higher in men. Additionally, male heat-related HHD mortality rates have shown a substantial increase over the past 30 years, whereas female rates have exhibited a comparatively modest decline.

Conclusion

Although cold remains the dominant non-optimal temperature factor, rising global temperatures suggest an increasing burden of heat-related HHD among the older adults. Efforts should prioritize strengthening resilience in vulnerable regions and populations, with targeted interventions to mitigate future health risks associated with temperature extremes.

Effects of Prolonged Cold Stress on Vascular Function in Guinea Pigs With Atherosclerosis

RESEARCH OBJECTIVE

This study explored the effects of long-term cold stress (CS) on aortic vascular function in guinea pigs.

RESEARCH METHODS

Hartley guinea pigs (n = 32) were divided into the following groups: atherosclerosis (AS), CS, and menthol-stimulated (M), and control (C). On days 1, 15, 30, 45, and 60, guinea pigs in the AS, CS, and M groups were intraperitoneally injected with bovine serum albumin. The C group was provided with maintenance feed and room temperature water. The AS group was provided with a high-fat diet and room temperature water. The CS group was maintained in a refrigerator at 4°C, while providing a high-fat diet and iced water. The M group was administered menthol solution, and provided with a high-fat diet and room temperature water. The modeling period lasted for 120 days. On day 121, abdominal aortic sera and aortic samples were obtained after intraperitoneal injection of sodium pentobarbital. Blood rheology tests were conducted to assess blood adhesion, biochemical tests to assess lipid levels, and enzyme-linked immunosorbent assays to detect serum nuclear factor-κB, tumor necrosis factor-α, and interleukin-1β, and endothelial nitric oxide synthase, nitric oxide, and endothelin-1 (ET-1) in aortic tissue. Hematoxylin and eosin and oil red O staining were used to examine pathologic changes in the aorta, Western blotting to detect transient receptor potential melastatin 8 and protein kinase G protein expression, quantitative polymerase chain reaction was used to measure VCAM-1 mRNA expression level.

RESEARCH FINDINGS

Prolonged exposure to CS exacerbated lipid-metabolism disorders in guinea pigs fed a high-fat diet, increased aortic vascular cell adhesion, and exacerbated vascular inflammation, leading to endothelial injury, ultimately worsening pathologic changes associated with aortic atherosclerosis.

Climate change, air pollution and chronic respiratory diseases: understanding risk factors and the need for adaptive strategies

Under the background of climate change, the escalating air pollution and extreme weather events have been identified as risk factors for chronic respiratory diseases (CRD), causing serious public health burden worldwide. This review aims to summarize the effects of changed atmospheric environment caused by climate change on CRD. Results indicated an increased risk of CRD (mainly COPD, asthma) associated with environmental factors, such as air pollutants, adverse meteorological conditions, extreme temperatures, sandstorms, wildfire, and atmospheric allergens. Furthermore, this association can be modified by factors such as socioeconomic status, adaptability, individual behavior, medical services. Potential pathophysiological mechanisms linking climate change and increased risk of CRD involved pulmonary inflammation, immune disorders, oxidative stress. Notably, the elderly, children, impoverished groups and people in regions with limited adaptability are more sensitive to respiratory health risks caused by climate change. This review provides a reference for understanding risk factors of CRD in the context of climate change, and calls for the necessity of adaptive strategies. Further interdisciplinary research and global collaboration are needed in the future to enhance adaptability and address climate health inequality.

The association between short-term apparent temperature exposure and human coagulation: A time-series study from Beijing, 2014-2023

A growing body of evidence suggests that non-optimal ambient temperatures are associated with increased incidence rate and mortality of thromboembolic diseases. We aim to investigate the association between apparent temperature (AT) and coagulation, which is a central pathological link in the formation of thrombi. In this study, we conducted a time series analysis using data from 18,894 participants collected from a health check-up center in Beijing between 2014 and 2023, and validated our findings using 20,549 participants from an andrology outpatient clinic. The daily mean AT was calculated using data on ambient temperature, relative humidity, and wind speed from Beijing. Participants were matched to the lagged moving average of AT (0-7 days) based on their specific health examination dates. The study employed generalized additive models to analyzed the linear and nonlinear associations between AT and coagulation indices. The results indicated that heat resulted in shortened prothrombin time and activated partial thromboplastin time, whereas cold resulted in shortened thrombin time. Fibrinogen showed an increase at both high and low temperatures. Logistic regression analysis revealed that the risk of hypercoagulable state increased in both high and low temperature environments compared to moderate temperatures, with a significant increase observed under extreme heat conditions. Subgroup analyses by sex and age, sensitivity analyses, and the external validation indicated that the association between AT and coagulation was robust. The findings support that both cold and heat can augment blood coagulability through distinct stages of the coagulation cascade, thereby leading to an elevated risk of thromboembolic diseases.