Association Between Ambient Heat and Risk of Emergency Department Visits for Mental Health Among US Adults, 2010 to 2019

Co-occurring climate events and environmental justice in California, 2018-2019

Climate change will increase the frequency of extreme weather events. This means climate-driven events like wildfires and power outages will likely co-occur more often, potentially magnifying their health risks. We characterized three types of climate-driven events-anomalously warm temperatures, wildfire burn zone disasters, and long power outages-in 58 California counties during 2018-2019. We defined county-day anomalously warm temperatures when daily average temperatures exceeded 24 °C and the 85th percentile of the long-term county average. We defined county-day wildfire burn zone disasters when an active wildfire burn zone intersected a county, burned 1+ structures, killed a civilian, or received a Federal Emergency Management Agency Fire Management Declaration, and overlapped with a community. For a subset of the 38 counties (66%), long power outage county days were identified using PowerOutage.us data when an outage affected >0.5% of county customers for 8+ h. Co-occurring events were when 2+ of these events occurred on the same county day. Using the CDC/ATSDR Social Vulnerability Index (SVI), we determined whether co-occurring events disproportionately affected vulnerable populations. Nearly every county (97%) experienced at least one day of anomalously warm temperatures, 57% had at least one wildfire burn zone disaster day, and 63% (24/38 counties with available data) had at least one long power outage day. The most common co-occurring events (anomalously warm temperatures and wildfire burn zone disasters) impacted 24 (41%) counties for 144 total county-days. We did not find a clear connection between co-occurring events and social vulnerability. We observed an inverse correlation between co-occurring wildfire burn zone disasters and long power outage days with SVI, and a positive correlation between co-occurring anomalously warm and long power outage days with SVI. This analysis can inform regional resource allocation and other state-wide planning and policy objectives to reduce the adverse effects of climate-driven events.

The impact of extreme high temperatures on ADRD hospitalization in Guangdong, China, 2017-2019

Alzheimer's disease and related dementias (ADRD) have emerged as a major global health challenge due to the aging population. This study is among the first to investigate the impact of extreme high temperatures on ADRD hospitalization in a developing country, leveraging individual-level inpatient medical records. We found that both transient and cumulative exposure to heat waves significantly increased total hospitalization expenses and the length of hospital stay for ADRD patients. Specifically, an additional day with a daily mean temperature exceeding 30 °C in the preceding 7 days, compared to a moderate day with a temperature between 14-18 °C, was associated with a 1.5 % (200.2 yuan) increase in total hospitalization expenses and a 1.8 % (0.2 days) increase in the length of hospital stay. These effects were largely driven by out-of-pocket expenditures on nursing care and were particularly pronounced among male patients and those aged over 75.

Assessing the impact of socioeconomic and environmental factors on mental health during the COVID-19 pandemic based on GPS-enabled mobile sensing and survey data

This study examines the impact of individual socioeconomic factors, living environment factors (e.g., housing conditions), and environmental exposures (e.g., greenspace) on people's mental health during the COVID-19 pandemic in Hong Kong. We measured the environmental exposures to greenspace, noise and air pollution using GPS tracking and mobile sensing data collected from survey participants, in addition to obtaining socioeconomic and living environment data from them using conventional survey questionnaires. We used an ordinal logistic regression model to determine the socioeconomic and environmental factors that are significantly associated with mental health outcomes. The results show that increased greenspace exposure is associated with a higher likelihood of better mental health outcomes, while both lower income level and home ownership with a mortgage are linked to lower odds of better mental health outcomes during the COVID-19 pandemic in Hong Kong. This research contributes to the existing literature by identifying the specific socioeconomic and environmental factors that significantly affect mental health outcomes during the COVID-19 pandemic.

Characterizing pediatric discharge diagnoses associated with daily extreme heat exposure in the Midwestern US: A retrospective case-crossover study

Aim

To explore the association between daily extreme heat exposure (daily mean temperature is greater than the 90th percentile for the month) and pediatric (birth to 18 years old) urgent care clinic, emergency department, and inpatient hospitalization discharge diagnoses for any causes and 12 individual morbidities of interest.

Design

A time-stratified, case-crossover study design.

Methods

We analyzed discharge diagnoses from the Saint Louis University-Sisters of St. Mary, a non-profit healthcare system in the United States, using the Virtual Data Warehouse. Our analysis encompassed urgent care clinic visits, emergency department visits, and hospitalizations within a Midwestern healthcare network across Missouri, Wisconsin, the Oklahoma City metropolitan area, and Southern Illinois, in the United States. Our study focused on all causes and examined 12 specific morbidities of interest. We focused on pediatric patients during the warm season months of May through September in 2017-2022. For all outcome models, an overall model was calculated and then each model was stratified by age, sex, race, and neighborhood socioeconomic status, excluding strata with unknown values.

Results

We found significant associations with dehydration, general symptoms, heat-related illnesses, and infections. The impact of extreme heat exposure varied across demographics, with vulnerable groups including children aged one to four, males, and individuals from low socioeconomic status areas.

Conclusions

Our findings highlight important opportunities for health promotion in communities and preschools. Better informing caregivers of the risks and implementing policy level initiatives may help reduce pediatric exposure to extreme heat. Future research should focus on longitudinal studies to explore these dynamics further and develop effective heat mitigation strategies to protect vulnerable pediatric populations from the adverse effects of extreme heat.

Heatwaves and its impact on the depressive symptoms among Chinese community-dwelling older adults: Examining the role of social participation

OBJECTIVES

Based on the Environment-Person Fit Perspective, this study explores the relationship between heatwaves and subsequent depressive symptoms among older Chinese community dwellers. Additionally, the study investigates if this association varies among older adults with different levels of social participation.

METHODS

Heatwaves were defined as the frequency of occurrences where daily maximum temperature exceeded 35 °C for 3 consecutive days. A sample including 7124 older adults aged 55 and above was selected from the 2018 China Health and Retirement Longitudinal Study. Depressive symptoms were measured by the 10-item Centre for Epidemiological Studies Depression Scale. Social participation was measured by volunteer participation and leisure participation. Multilevel fixed effect model was employed to investigate the temporal association between heatwaves and depressive symptoms, as well as the moderating effect of social participation.

RESULTS

This study found that older adults who had experienced a greater number of heatwaves presented more severe depressive symptoms (b = 0.66, p < 0.001). However, a high level of leisure participation buffered the effect of heatwaves on depressive symptoms (b = ̶ 0.52, p < 0.05).

CONCLUSIONS

This study highlighted the differential impact of heatwaves on mental health outcomes among older adults depending on their levels of social participation. Our findings provide valuable insights into designing an integrative heatwave adaption scheme that simultaneously focuses on temperature adjustment and social participation enhancement.

An exploratory study of household conditions and youth personal exposure to extreme heat during a heatwave in urban Nashville, Tennessee, USA

Extreme heat is the deadliest meteorological hazard and is increasingly affecting the southeastern United States. Health effects of extreme heat are often not felt for hours or days after exposure and disproportionately affect vulnerable populations (e.g., youth, minorities). Personal heat exposure research has focused on occupational and everyday heat exposure among adults. To date, heat exposure in teenage populations has not been investigated. This population has unique heat exposure patterns that result from lifestyles that include outdoor jobs (e.g., lifeguard) and participation in outdoor sports. Better understanding of these exposure patterns is needed to reduce youth exposure and illnesses during heat events. Likewise, there have been no studies comparing paired indoor home conditions with individual exposure. Participants (n = 10) wore sensors to collect six days of personal heat exposure data (temperature and humidity) and placed sensors in and around their homes to collect ambient household data. When comparing individual exposure with ambient outdoor conditions and household conditions, this study revealed that: 1) teenagers are less exposed to dangerous heat (> 37.8 °C heat index) during the day; 2) teenagers are more exposed to dangerous heat (> 23.9 °C temperature) at night; 2) some teenagers are exposed to long periods of high heat at night, which is typically a time for heat recovery; and 3) household temperatures are typically not representative of heat exposure. To better understand teen exposure, we recommend future research focus on larger, representative sample sizes, collecting exposure data during the school year, and comparing exposure between heatwave and normal summer conditions.

Mental health disparities among maternal populations following heatwave exposure in North Carolina (2011-2019): a matched analysis

Background

The increasing incidence of extreme heat due to climate change poses a significant threat to maternal mental health in the U.S. We examine the association of acute exposure to heatwaves with maternal mental health conditions in North Carolina from 2011 to 2019.

Methods

We incorporate a matched analysis design using NC Hospital Discharge Data to examine emergency department admissions for psychiatric conditions during the warm season (May to September), matching heatwave periods with non-heatwave unexposed periods at the zip code tabulation area (ZCTA) level. We stratify the sample to examine effect modification across the rural-urban continuum, physiographic regions, measurements of neighborhood racial and economic inequality, and individual-level sociodemographic factors (e.g., age, race/ethnicity, and insurance type).

Findings

Our sample of 324,928 emergency department visits by pregnant individuals has a mean age of 25.8 years (SD: 5.84), with 9.3% (n = 30,205) identifying as Hispanic. Relative risk (RR) estimates and 95% confidence intervals (CI) indicate significant increases in maternal mental health burdens following heatwave exposure. Acute heatwave periods were associated with a 13% higher risk of severe mental illness (RRSMI: 1.13, CI: 1.08-1.19, p: <0.0001), while prolonged exposure to moderate-intensity heatwaves was associated with 37% higher risk (RRSMI: 1.37, CI: 1.19-1.58, p: <0.001). Individual factors (e.g., advanced maternal age and insurance providers) and neighborhood-level characteristics, like low socioeconomic status, racialized and economic segregation, rurality, and physiographic region, further modified the risk of adverse maternal mental health outcomes.

Interpretation

Our results add to the growing evidence of the impact of extreme heat on maternal mental health, particularly among vulnerable subpopulations. Additionally, findings emphasize the influence of socioeconomic and environmental contexts on mental health responses to heatwave exposure.

Funding

This work was supported by the Faculty Early Career Development Program (CAREER) award (grant #2044839) from the National Science Foundation and the National Institute of Environmental Health Sciences (NIEHS) award (grant #5R03ES035170-02).

Mental Health Vulnerabilities and Environmental Justice: A Collaborative Online International Learning Experience

Collaboration and intercultural interaction and engagement are relevant to all aspects of higher education including distance/remote/virtual courses. Collaborative Online International Learning (COIL) experiences connect students in different countries and provide them with meaningful and significant opportunities for global and intercultural exposure. Such an educational environment enhances students' cultural awareness and knowledge, and guides their personal, relational, and professional actions. Accordingly, engagement in COIL experiences can increase students' understanding of and ability to respond to significant global health-care issues both locally and internationally and to recognize their impact on mental health, and can lead to reflection and awareness that will endure beyond students' individual class experiences. One of these urgent issues is mental health vulnerabilities associated with environmental justice issues. This article describes participation in an international collaborative experience between the Universidad San Francisco de Quito, Ecuador, and the College of Nursing at the University of South Alabama, USA.

Climate change and suicide epidemiology: a systematic review and meta-analysis of gender variations in global suicide rates

Background

Climate change is reshaping public health, introducing extreme weather conditions and environmental stressors-such as high temperatures, atmospheric pollution, desertification, and storms (rain, thunder, and hail)-that critically impact mental health. Evidence increasingly links these factors to higher rates of suicide-related outcomes, including suicidal ideation, attempts, and self-harm. Such interactions underscore the importance of understanding how climate-driven mental health risks vary by environmental factor and gender, as gender-specific vulnerabilities shape responses to climate stressors.

Methods

By April 16, 2024, we conducted a comprehensive search of PubMed, Web of Science, Cochrane Library, PsycINFO, Scopus, ProQuest, and Embase. Two researchers independently reviewed studies and collected demographic data, systematically tracking and recording rates of suicidal ideation, suicide attempts, suicide deaths, self-harm, and anxiety. Data were rigorously cross-verified for accuracy and consistency.

Results

The meta-analysis demonstrated significant associations between climate change variables and mental health outcomes. High temperatures and air pollution were linked to increased suicide attempts (OR: 1.40, 95% CI: 1.34-1.45) and suicide deaths (OR: 1.51, 95% CI: 1.44-1.58), particularly among males. Conversely, atmospheric pollution and desertification correlated with a reduced likelihood of suicidal ideation (OR: 0.73, 95% CI: 0.63-0.85). These findings highlight gender-specific mental health impacts, with females exhibiting higher rates of anxiety and self-harm, underscoring the urgent need for targeted interventions addressing climate-induced mental health risks.

Conclusions

This systematic review and meta-analysis reveal significant gender-specific mental health impacts of climate change, with females experiencing higher rates of anxiety, self-harm, and suicidal ideation, while males show greater incidences of suicide attempts and deaths. These findings emphasize the urgent need for targeted interventions and the integration of mental health services into climate policies to address these gender disparities.

Systematic review registration

This study is registered with PROSPERO [PROSPERO (york.ac.uk)] under the identifier [CRD42024534961].

Youth suicidality risk relative to ambient temperature and heatwaves across climate zones: A time series analysis of emergency department presentations in New South Wales, Australia

OBJECTIVE

Youth suicidality prevalence continues to rise alongside hot weather severity. Links between these two variables are underexplored. We examined associations between daily temperature and emergency department suicidality presentations by young people. We assessed these associations for five regions covering New South Wales as determined by 'climate zone' and analysed for heatwave effects as well as based on demographic subgroups.

METHODS

Daily emergency department presentations for suicidality by people aged 12-24 years across New South Wales, Australia, during warmer months (November to March) from 2012 to 2019 were examined in relation to daily mean temperature and heatwaves (⩾3 consecutive days ⩾ 95th percentile of long-term daily mean temperature) and by climate zone, using a generalised additive model with negative binomial distribution. Risks for age- and sex-based subgroups were also calculated.

RESULTS

New South Wales youth suicidality presentation rates were significantly higher on hotter days. For every 1°C rise above average daily mean temperature, youth suicidality presentations to New South Wales emergency departments increased by 1.3%. Heatwaves did not increase presentation rates beyond single-day daily mean temperature effects. These findings were predominantly replicated across climate zones and demographic subgroups, though the association between suicidality and ambient temperature was weaker in coastal regions including Eastern Sydney.

CONCLUSION

There is a positive linear association between ambient temperature and youth suicidality presentations to emergency departments. Risks are increased on single hot days, not only during heatwaves. Public health, broader societal approaches to heat and health system planning should consider impacts on youth suicidality of predicted increases in hot weather severity and frequency.

Effects of ambient temperature on mental and neurological conditions in older adults: A systematic review and meta-analysis

BACKGROUND

Emerging research has suggested a link between ambient temperature and mental and neurological conditions such as depression and dementia. This systematic review aims to summarize the epidemiological evidence on the effects of ambient temperature on mental and neurological conditions in older adults, who may be more vulnerable to temperature-related health effects compared to younger individuals.

METHODS

A systematic search was conducted in PubMed, Ovid/Embase, Web of Science, and Ovid/PsycINFO on July 17, 2023, and updated on July 31, 2024. We included epidemiological studies investigating the association between ambient temperature exposures and numerous mental and neurological conditions in populations aged 60 years and older. Exclusions were made for studies on indoor or controlled exposure, suicide, substance abuse, those not published as peer-reviewed journal articles, or those not written in English. The risk of bias of included studies was assessed using a tool developed by the World Health Organization (WHO). Qualitative synthesis was performed on all eligible studies, and random-effects meta-analyses were conducted on groups of at least four studies sharing similar study design, exposure metric, and health outcome. The certainty of evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework modified by the WHO.

RESULTS

From 16,786 screened articles, 76 studies were deemed eligible, primarily from mainland China and North America. There was notable heterogeneity in study variables and methodologies. The most commonly used exposure metrics were daily absolute temperature and heat waves, and time-series and case-crossover analyses were the most frequently employed study designs. Meta-analysis of four studies on the effect of a 1 °C increase in temperature on hospital admissions/visits for mental disorders showed a pooled risk ratio (RR) of 1.014 (95 % Confidence Interval, CI: 1.001, 1.026). Comparing heat wave days to non-heat wave days, pooled effect estimates showed increased risk in hospital admissions/visits (RR: 1.269; 95 % CI: 1.030, 1.564; six studies) and mortality related to mental disorders (RR: 1.266; 95 % CI: 0.956, 1.678; four studies). Despite the limited number of studies on cold exposures, they consistently reported that lower temperatures were associated with an increased risk of various mental and neurological conditions.

CONCLUSIONS

This review presents epidemiological evidence of the adverse impacts of ambient temperature exposures, such as high temperatures and heat waves, on mental and neurological conditions among the older adult population, with overall moderate certainty. The findings highlight the need for greater attention to the mental and neurological health of older adults in the context of climate change and population aging. Registration number (PROSPERO ID): CRD42023428137.

How does climate change impact people who use alcohol and other drugs? A scoping review of peer reviewed literature

BACKGROUND

The world has experienced devastating extreme weather events, alongside slow-onset processes including increasing temperature means, that scientists agree are manifestations of human-induced climate change. Even with radical action to reduce greenhouse gas emissions, effects of climate change will become increasingly severe.

OBJECTIVES

The aim of this review was to classify impacts of climate change for people who use alcohol and other drugs (AoD), as reflected in peer reviewed literature.

METHOD

A scoping review was conducted to achieve this. Included studies involved a human population, a climate change related exposure, and an AoD outcome. Studies were published in English between 1998 and November 2023. Exposure events of interest included extreme heat, fires, storms, floods, droughts, and longer-term environmental changes. 8,204 studies were screened, with 82 included for data extraction and narrative analysis.

RESULTS

Most papers describe increased AoD use, with smaller numbers showing decreased or unchanged substance use. Some studies identify unplanned withdrawal, changed drug markets, disrupted service access, specific physiological vulnerabilities of AoD users to extreme heat, and compounding effects on mental health. We note the relative absence of peer reviewed studies investigating impacts of climate change on AoD use in low-and middle-income countries. Further, few studies consider impacts that occur because of long-term or gradual climatic shifts such as environmental changes that are detrimental to livelihoods.

CONCLUSION

It is crucial to document effects of a changing climate on people who use AoD so that policy and services can meet future needs. We call for research to remedy gaps identified in this review.

The 2024 report of the Lancet Countdown on health and climate change: facing record-breaking threats from delayed action

Despite the initial hope inspired by the 2015 Paris Agreement, the world is now dangerously close to breaching its target of limiting global multiyear mean heating to 1·5°C. Annual mean surface temperature reached a record high of 1·45°C above the pre-industrial baseline in 2023, and new temperature highs were recorded throughout 2024. The resulting climatic extremes are increasingly claiming lives and livelihoods worldwide.

The Lancet Countdown: tracking progress on health and climate change was established the same year the Paris Agreement entered into force, to monitor the health impacts and opportunities of the world’s response to this landmark agreement. Supported through strategic core funding from Wellcome, the collaboration brings together over 300 multidisciplinary researchers and health professionals from around the world to take stock annually of the evolving links between health and climate change at global, regional, and national levels.

The 2024 report of the Lancet Countdown, building on the expertise of 122 leading researchers from UN agencies and academic institutions worldwide, reveals the most concerning findings yet in the collaboration’s 8 years of monitoring.

Association of Postpartum Temperature Exposure with Postpartum Depression: A Retrospective Cohort Study in Southern California

BACKGROUND

Postpartum depression (PPD) has been associated with biological, emotional, social, and environmental factors. However, evidence regarding the effect of temperature on PPD is extremely limited.

OBJECTIVES

We aimed to examine the associations between postpartum temperature exposure and PPD.

METHODS

We conducted a retrospective cohort study using data from Kaiser Permanente Southern California electronic health records from 1 January 2008 through 31 December 2018. PPD was first assessed using the Edinburgh Postnatal Depression Scale (score ≥ 10 ) during the first year of the postpartum period and further identified by using both diagnostic codes and prescription medications. Historical daily ambient temperatures were obtained from the 4 -km resolution gridMET dataset (https://www.climatologylab.org/gridmet.html) and linked to participants' residential addresses at delivery. Postpartum temperature exposures were measured by calculating various temperature metrics during the period from delivery to PPD diagnosis date. A time-to-event approach with a discrete-time logistic regression was applied to estimate the association between temperature exposure and time to PPD. Effect modification by maternal characteristics and other environmental factors was examined.

RESULTS

There were 46,114 (10.73%) PPD cases among 429,839 pregnancies (mean ± standard deviation age = 30.22 ± 5.75 y). Increased PPD risks were positively associated with exposure to higher mean temperature [adjusted odds ratio (aOR) per interquartile range increment: 1.07; 95% confidence interval (CI): 1.05, 1.09] and diurnal temperature range (aOR = 1.08 ; 95% CI: 1.06, 1.10); the associations were stronger for maximum temperature compared with minimum temperature. The temperature-related PPD risks were greater among African American, Asian, and Hispanic mothers and among mothers ≥ 25 years of age compared with their counterparts. We also observed higher effects of temperature on PPD among mothers exposed to higher air pollution or lower green space levels and among mothers with lower air conditioning penetration rates.

CONCLUSION

Maternal exposure to higher temperature and diurnal temperature variability during the postpartum period was associated with an increased risk of PPD. Effect modification by maternal age, race/ethnicity, air pollution, green space, and air conditioning penetration was identified. https://doi.org/10.1289/EHP14783.

Generalizability of Heat-related Health Risk Associations Observed in a Large Healthcare Claims Database of Patients with Commercial Health Insurance

BACKGROUND

Extreme ambient heat is unambiguously associated with a higher risk of illness and death. The Optum Labs Data Warehouse (OLDW), a database of medical claims from US-based patients with commercial or Medicare Advantage health insurance, has been used to quantify heat-related health impacts. Whether results for the insured subpopulation are generalizable to the broader population has, to our knowledge, not been documented. We sought to address this question, for the US population in California from 2012 to 2019.

METHODS

We examined changes in daily rates of emergency department encounters and in-patient hospitalization encounters for all-causes, heat-related outcomes, renal disease, mental/behavioral disorders, cardiovascular disease, and respiratory disease. OLDW was the source of health data for insured individuals in California, and health data for the broader population were gathered from the California Department of Health Care Access and Information. We defined extreme heat exposure as any day in a group of 2 or more days with maximum temperatures exceeding the county-specific 97.5th percentile and used a space-time-stratified case-crossover design to assess and compare the impacts of heat on health.

RESULTS

Average incidence rates of medical encounters differed by dataset. However, rate ratios for emergency department encounters were similar across datasets for all causes [ratio of incidence rate ratios (rIRR) = 0.989; 95% confidence interval (CI) = 0.969, 1.009], heat-related causes (rIRR = 1.080; 95% CI = 0.999, 1.168), renal disease (rIRR = 0.963; 95% CI = 0.718, 1.292), and mental health disorders (rIRR = 1.098; 95% CI = 1.004, 1.201). Rate ratios for inpatient encounters were also similar.

CONCLUSIONS

This work presents evidence that OLDW can continue to be a resource for estimating the health impacts of extreme heat.

Heat Waves and Adverse Health Events Among Dually Eligible Individuals 65 Years and Older

Importance

Extensive research has found the detrimental health effects of heat waves. However, a critical gap exists in understanding their association with adverse health events among older dually eligible individuals, who may be particularly susceptible to heat waves.

Objective

To assess the association between heat waves and adverse health events among dually eligible individuals 65 years and older.

Design, Setting, and Participants

This retrospective time-series study assessed the association between heat waves in warm months from 2016 to 2019 and zip code tabulation area (ZCTA)-day level adverse health events. Dually eligible individuals 65 years and older who were continuously enrolled in either a Medicare fee-for-service plan or a Medicare Advantage plan with full Medicaid benefits from May to September in any given year were identified. All ZCTAs in the US with at least 1 dually eligible individual in each study year were included. Data were analyzed from September 2023 to August 2024.

Exposure

Heat waves, defined as 3 or more consecutive extreme heat days (ie, days with a maximum temperature of at least 90 °F [32.2 °C] and in the 97th percentile of daily maximum temperatures for each ZCTA during the study period).

Main Outcomes and Measures

Daily counts of heat-related emergency department visits and heat-related hospitalizations for each ZCTA.

Results

The study sample included 5 448 499 beneficiaries 65 years and older in 28 404 ZCTAs across 50 states and Washington, DC; the mean (SD) proportion of female beneficiaries and beneficiaries 85 years and older in each ZCTA was 66% (7%) and 20% (8%), respectively. The incidence rate for heat-related emergency department visits was 10% higher during heat wave days compared to non-heat wave days (incidence rate ratio [IRR], 1.10; 95% CI, 1.08-1.12), and the incidence rate of heat-related hospitalizations was 7% higher during heat wave days (IRR, 1.07; 95% CI, 1.04-1.09). There were similar patterns in other adverse health events, including a 4% higher incidence rate of death during heat wave days (IRR, 1.04; 95% CI, 1.01-1.07). The magnitude of these associations varied across some subgroups. For example, the association between heat waves and heat-related emergency department visits was statistically significant only for individuals in 3 of 9 US climate regions: the Northwest, Ohio Valley, and the West.

Conclusions and Relevance

In this time-series study, heat waves were associated with increased adverse health events among dually eligible individuals 65 years and older. Without adaptation strategies to address the health-related impacts of heat, dually eligible individuals are increasingly likely to face adverse outcomes.

Association Between Extreme Heat and Outpatient Visits for Mental Disorders: A Time-Series Analysis in Guangzhou, China

Previous evidence on heatwaves' impact on mental health outpatient visits is limited, especially uncertainty on how different heatwave definitions affect this relationship. In this time-series study, we assessed the association between heatwaves and outpatient visits for mental disorders in Guangzhou, China. Daily outpatient visits for mental disorders and its specific categories (schizophrenia, mood, and neurotic disorders) were sourced from the Urban Resident-based Basic Medical Insurance (URBMI) and the Urban Employee-based Basic Medical Insurance (UEBMI) claims databases in Guangzhou from 2010 to 2014. The study employed nine heatwave definitions, based on combinations of three daily mean temperature thresholds (90th, 92.5th, and 95th percentiles) and durations (2, 3, and 4 days). Using quasi-Poisson generalized linear models (GLMs), we estimated the risks (at lag 0 day) and cumulative effects (lag 0-10 days) of heatwaves on mental disorder outpatient visits. Age, gender, types of medical insurance were considered as potential effect modifiers. We observed a positive association between heatwaves and increased total outpatient visits for mental disorders, both at lag 0 day and during lag 0-10 days. The impact of heatwave was significant at lag 0 day for schizophrenia, mood and neurotic disorders visits, it remained significant for neurotic and mood disorders visits during lag 0-10 days. Heatwave durations lasting more than 4 days were associated with higher relative risks of mental disorders at lag 0 day. Older adults had relatively higher effect estimations than younger individuals. This research highlights the effects of extreme heat on mental health.

["Is there a Link Between Heat Waves and Mental Health Emergencies in the Emergency Department?"]

OBJECTIVE

There is evidence suggesting that climate change, coupled with an increase in the frequency and severity of heatwaves, affects mental health. The aim of this study was to investigate potential associations between high temperature and the utilization of an emergency department (ED) by individuals with psychiatric disorders.

METHODS

A retrospective analysis of all psychiatric emergency patients from 2015 to 2022 (N=15478) was conducted and compared with local temperature data.

RESULTS

Particularly during heatwaves, more psychiatric emergency patients presented to the ED.

CONCLUSION

Beyond the results identified during heatwaves, our extensive analysis of the examined ED revealed no additional significant effects of heat on psychiatric emergencies. This contradicts findings from other studies. Other systemic influences, such as the utilization of the ED during the Covid-19 pandemic, could have modified the results.

Variable and dynamic associations between hot weather, thermal comfort, and individuals' emotional states during summertime

The effects of heat exposure on negative affect are thought to be central to the observed relationships between hot summer days and deleterious outcomes, such as violent crime or mental health crises. As these relationships are likely to be magnified by the effects of climate change, a better understanding of how consistent or variable the effects of hot weather on affective states is required. The current work combines data gathered from an ecological momentary assessment (EMA) study on individuals' thermal perceptions, comfort, and affective states in outdoor environments during their daily lives with high spatiotemporal resolution climate-modeled weather variables. Using these data, associations between objective weather variables (temperature, humidity, etc.), perceived heat (thermal perception and comfort), and affective states are examined. Overall, objective weather data reasonably predicted perception and comfort, but only comfort predicted negative affective states. The variance explained across individuals was generally very low in predicting negative affect or comfort, but within-person variance explained was high. In other words, while there may be a relatively consistent relationship between temperature and psychological experience for any given person, there are significant individual differences across people. Age and gender were examined as moderators of these relationships, and while gender had no impact, participant age showed several significant interactions. Specifically, while older adults tended to experience more thermal discomfort and perceived higher temperatures as hotter, the relationship between discomfort and negative affect was lower in older adults. Taken together, these results emphasize the importance of thermal discomfort specifically in predicting negative affect, as well as the high inter-individual variability in thermal perceptions and comfort for the same ambient temperatures.

Daily temperature variability and mental health-related hospital visits in New York State

BACKGROUND

Despite plausible behavioral and physiological pathways, limited evidence exists on how daily temperature variability is associated with acute mental health-related episodes.

OBJECTIVES

We aimed to explore associations between daily temperature range (DTR) and mental health-related hospital visits using data of all hospital records in New York State during 1995-2014. We further examined factors that may modify these associations, including age, sex, hospital visit type and season.

METHODS

Using a case-crossover design with distributed lag non-linear DTR terms (0-6 days), we estimated associations between ZIP Code-level DTR and hospital visits for mood (4.6 million hospital visits), anxiety (2.4 million), adjustment (∼368,000), and schizophrenia disorders (∼211,000), controlling for daily mean temperature, via conditional logistic regression models. We assessed potential heterogeneity by age, sex, hospital visit type (in-patient vs. out-patient), and season (summer, winter, and transition seasons).

RESULTS

For all included outcomes, we observed positive associations from period minimum DTR (0.1 °C) until 25th percentile (5.2 °C) and between mean DTR (7.7 °C) and 90th percentile (12.2 °C), beyond which we observed negative associations. For mood disorders, an increase in DTR from 0.1 °C to 12.2 °C was associated with a cumulative 16.0% increase (95% confidence interval [CI]: 12.8, 19.2%) in hospital visit rates. This increase was highest during transition seasons (32.5%; 95%CI: 26.4, 39.0%) compared with summer (10.7%; 95%CI: 4.8, 16.8%) and winter (-1.6%; 95%CI: -7.6, 4.7%). For adjustment and schizophrenia disorders, the strongest associations were seen among the youngest group (0-24 years) with almost no association in the oldest group (65+ years). We observed no evidence for modification by sex and hospital visit type.

DISCUSSION

Daily temperature variability was positively associated with mental health-related hospital visits within specific DTR ranges in New York State, after controlling for daily mean temperature. Given uncertainty on how climate change modifies temperature variability, additional research is crucial to comprehend the implications of these findings, particularly under different scenarios of future temperature variability.

What do Climate Change, Nutrition, and the Environment Have to do With Mental Health?

Climate change is becoming the most significant global challenge and must be addressed on a global scale. At the time that this article is being written, the planetary heat in 2023 was the hottest on record. Similarly, the World Health Organization reports that 99% of the world's population lives in regions of unhealthy air pollution. Similarly, depression has become one of the leading causes of global mental and physical disabilities, and the impact of depression is predicted to only worsen over the next 25 years. It is interesting to note that climate experts often overlook the adoption of nutrition via a whole plant-based diet as a solution to both mental illness and climate change. In this review, we will touch upon the role of nutrition in gut microbiota and mental health, the impact diet has on greenhouse gases, the role of ultra-processed food, and environmental factors such as air pollution and increasing planetary heat and their growing impacts on mental health. In the end, the promotion of plant-based foods has the potential to improve personal mental and physical health while improving planetary health.

NPCC4: Climate change and New York City's health risk

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report considers climate health risks, vulnerabilities, and resilience strategies in New York City's unique urban context. It updates evidence since the last health assessment in 2015 as part of NPCC2 and addresses climate health risks and vulnerabilities that have emerged as especially salient to NYC since 2015. Climate health risks from heat and flooding are emphasized. In addition, other climate-sensitive exposures harmful to human health are considered, including outdoor and indoor air pollution, including aeroallergens; insect vectors of human illness; waterborne infectious and chemical contaminants; and compounding of climate health risks with other public health emergencies, such as the COVID-19 pandemic. Evidence-informed strategies for reducing future climate risks to health are considered.

Upper- vs. Whole-Body Cooling During Exercise with Thermal Protective Clothing in the Heat

INTRODUCTION: Firefighters operating in hot environments face challenges from protective garments that restrict heat dissipation, resulting in increased core temperature, thermal discomfort, and performance decline. Cooling vests represent a viable solution. The study aim was to compare effectiveness of the same amount of cooling power to the upper body (UB) or whole body (WB) in alleviating thermoregulatory and physiological stress, enhancing cognitive function, and reducing ratings of thermal discomfort and exertion, during 60 min of exercise in a hot environment (40°C, 40% relative humidity) while wearing firefighter turnout gear.METHODS: Eight healthy individuals (27.5 ± 3 y) participated in three conditions with either no cooling (Control) or active cooling with a liquid perfused shirt (UB cooling), or with a liquid perfused shirt and pants (WB cooling). In each trial, subjects performed three sets of 15 min of stepping (20 steps ⋅ min-1) and 5 min of rest.RESULTS: Both cooling strategies were beneficial compared to having no cooling at all. Subjects could only complete two exercise bouts during Control, but they completed all three bouts with active cooling. WB cooling provided an advantage over UB cooling for core and skin temperature, and thermal comfort and sensation. The advantage in minimizing the increase in core temperature was only evident during the third exercise bout.DISCUSSION: Active cooling is advantageous under these conditions. WB cooling provided some benefits vs UB cooling during heavy intensity exercise; however, it is uncertain whether these benefits would be observed during light-to-moderate exercise, which more likely reflects an actual firefighting scenario.Mansouri F, Talebian Nia M, Villar R, Cornish SM, Giesbrecht GG. Upper- vs. whole-body cooling during exercise with thermal protective clothing in the heat. Aerosp Med Hum Perform. 2024; 95(9):659-666.

Examining the non-linear association between ambient temperature and mental health of elderly adults in the community: evidence from Guangzhou, China

The association between ambient temperature and mental health has been explored previously. However, research on the psychological effect of temperature in vulnerable groups and neighborhood scales have been scarce. Based on the survey and temperature data collected from 20 neighborhoods in Guangzhou, China, this study estimated the association between ambient temperature and community mental health among the elderly, adopting a fixed-effects methodology. According to this empirical analysis, compared to a comfortable temperature range of 20℃-25℃, measures of worse mental health among elderly were significant in high and low temperatures with increases in negative outcomes observable at both ends of the temperature range, leading to the U-shaped relationship. Second, the association between ambient temperature and worse mental health was found in the subcategories of gender, income, and symptom events. Specifically, from the hot temperature aspect, elderly males were more sensitive than elderly females. The effect on the low was far more than on the middle-high income group, and the probability of each symptom of the elderly's mental health significantly increased. From the cool temperature aspect, the temperature in the range of 5ºC-10ºC was significantly associated with the probability of some symptoms (feeling down, not calm, downheartedness, and unhappiness) and the middle-high income group. Our research enriches the empirical research on ambient temperature and mental health from a multidisciplinary perspective and suggests the need for healthy aging and age-friendly planning in Chinese settings.

Urban heatwave, green spaces, and mental health: A review based on environmental health risk assessment framework

Utilizing the framework of environmental health risk assessment and healing, the article reviews the effectiveness and potential of green space systems in mitigating the impact of high temperatures, promoting mental health, and improving the risk characteristics of high-temperature heat waves. We utilized CiteSpace software to conduct a time-zone analysis of the relationship between heatwaves, green spaces, and health using clustered data from 2001 to 2023. This study evaluates the role of green space systems in mitigating high temperatures and enhancing mental health within the environmental health risk assessment framework. Using CiteSpace software, we analyzed literature from 2001 to 2023, focusing on the interactions among heatwaves, green spaces, and health. Our results indicate that most existing research concentrates on hazard identification, with insufficient exploration of the dose-response relationships between green spaces and temperature reduction. Quantitative studies on green space design and spatial optimization are scarce, and guidance on effective configurations remains limited. Additionally, the health impacts of heatwaves vary by region, with a noticeable imbalance in research focus; Asia and Africa, in particular, are underrepresented in studies addressing heatwave effects. We conclude that effective mitigation strategies require: (1) a comprehensive environmental health risk assessment framework that integrates advanced methods like big data analysis and geospatial simulations to improve green space planning and design; (2) further theoretical exploration into the mechanisms by which green spaces regulate temperature and mental health, including detailed analysis of spatiotemporal patterns and the functional optimization of green space structures; and (3) the development of robust parameterized design guidance based on specific therapeutic dosages (green space stimulus) to optimize configurations and enhance the effectiveness of green spaces in mitigating adverse mental health impacts from deteriorating thermal environments. Future research should prioritize underrepresented regions, focusing on exposure levels, dose-response relationships, and high-temperature warning systems while fostering multidisciplinary collaboration to develop effective urban planning and climate adaptation strategies.

Global climate change: Effects of future temperatures on emergency department visits for mental disorders in Beijing, China

Rising temperatures can increase the risk of mental disorders. As climate change intensifies, the future disease burden due to mental disorders may be underestimated. Using data on the number of daily emergency department visits for mental disorders at 30 hospitals in Beijing, China during 2016-2018, the relationship between daily mean temperature and such visits was assessed using a quasi-Poisson model integrated with a distributed lag nonlinear model. Emergency department visits for mental disorders attributed to temperature changes were projected using 26 general circulation models under four climate change scenarios. Stratification analyses were then conducted by disease subtype, sex, and age. The results indicate that the temperature-related health burden from mental disorders was projected to increase consistently throughout the 21st century, mainly driven by high temperatures. The future temperature-related health burden was higher for patients with mental disorders due to the use of psychoactive substances and schizophrenia as well as for women and those aged <65 years. These findings enhance our knowledge of how climate change could affect mental well-being and can be used to advance and refine targeted approaches to mitigating and adapting to climate change with a view on addressing mental disorders.

Closing the loop between environment, brain and mental health: how far we might go in real-life assessments?

PURPOSE OF REVIEW

Environmental factors such as climate, urbanicity, and exposure to nature are becoming increasingly important influencers of mental health. Incorporating data gathered from real-life contexts holds promise to substantially enhance laboratory experiments by providing a more comprehensive understanding of everyday behaviors in natural environments. We provide an up-to-date review of current technological and methodological developments in mental health assessments, neuroimaging and environmental sensing.

RECENT FINDINGS

Mental health research progressed in recent years towards integrating tools, such as smartphone based mental health assessments or mobile neuroimaging, allowing just-in-time daily assessments. Moreover, they are increasingly enriched by dynamic measurements of the environment, which are already being integrated with mental health assessments. To ensure ecological validity and accuracy it is crucial to capture environmental data with a high spatio-temporal granularity. Simultaneously, as a supplement to experimentally controlled conditions, there is a need for a better understanding of cognition in daily life, particularly regarding our brain's responses in natural settings.

SUMMARY

The presented overview on the developments and feasibility of "real-life" approaches for mental health and brain research and their potential to identify relationships along the mental health-environment-brain axis informs strategies for real-life individual and dynamic assessments.

Association of Psychiatric Emergency Visits and Warm Ambient Temperature during Pregnancy: A Time-Stratified Case-Crossover Study

BACKGROUND

Acute exposure to high ambient temperature and heat waves during the warm season has been linked with psychiatric disorders. Emerging research has shown that pregnant people, due to physiological and psychological changes, may be more sensitive to extreme heat, and acute exposure has been linked to increased risk of pregnancy complications; however, few studies have examined psychiatric complications.

OBJECTIVE

Our objective was to examine the association between acute exposure to warm ambient temperatures and emergency department (ED) visits for mental disorders during pregnancy.

METHODS

A time-stratified case-crossover design with conditional logistic regression was performed on ∼ 206,000 psychiatric ED visits for pregnant patients in North Carolina, from May to September 2016 to 2019. Daily average ambient temperature was the main exposure and was linked to daily visits by maternal zip code of residence for prenatal mood and anxiety disorders (PMAD), severe mental illness (SMI), mental disorder of pregnancy (MDP), suicidal thoughts (SUIC), and any psychiatric disorder (Any). Effect modification by trimester, residential segregation, economic segregation, urbanicity, and availability of greenspace was also investigated.

RESULTS

Each 5 ° C increase in same-day exposure to warm ambient temperature on case days was associated with an increase in incidence rate ratio (IRR) for any psychiatric disorder [IRR = 1.07; 95% confidence interval (CI): 1.01, 1.14] including anxiety (IRR = 1.14; 95% CI: 1.00, 1.30), bipolar disorder (IRR = 1.28; 95% CI: 0.98, 1.67), and suicidal thoughts (IRR = 1.28; 95% CI: 1.00, 1.65) compared to control days. In general, the associations were strongest for warm season temperatures on the same day of exposure or for temperatures averaged over the 3 or 6 d preceding the ED visit. The greatest risk of an incident ED admission for PMAD (RR = 1.20; 95% CI: 1.04, 1.39), particularly for anxiety (RR = 1.30; 95% CI: 1.07, 1.59), and any psychiatric disorder (RR = 1.17; 95% CI: 1.07, 1.28) occurred following cumulative exposure to hot temperatures the week before admission. Higher psychiatric burden from temperature was observed in urban areas and on extreme heat days.

CONCLUSIONS

For this pregnant population in the southeastern United States, short-term exposure to high ambient temperatures during the warm season was associated with a greater risk of ED visits for an array of psychiatric disorders. Findings show that climate-related increases in ambient temperature may contribute to psychiatric morbidity in pregnant people. https://doi.org/10.1289/EHP13293.

Climate change and disorders of the nervous system

Anthropogenic climate change is affecting people's health, including those with neurological and psychiatric diseases. Currently, making inferences about the effect of climate change on neurological and psychiatric diseases is challenging because of an overall sparsity of data, differing study methods, paucity of detail regarding disease subtypes, little consideration of the effect of individual and population genetics, and widely differing geographical locations with the potential for regional influences. However, evidence suggests that the incidence, prevalence, and severity of many nervous system conditions (eg, stroke, neurological infections, and some mental health disorders) can be affected by climate change. The data show broad and complex adverse effects, especially of temperature extremes to which people are unaccustomed and wide diurnal temperature fluctuations. Protective measures might be possible through local forecasting. Few studies project the future effects of climate change on brain health, hindering policy developments. Robust studies on the threats from changing climate for people who have, or are at risk of developing, disorders of the nervous system are urgently needed.

The Impact of COVID-19 Vaccination on Symptoms of Anxiety and Depression before and after COVID-19 Vaccines Were Universally Available for Adults in the United States

Our objective was to examine the influence of COVID-19 vaccination on recent (i.e., past month) moderate or severe symptoms of anxiety (GAD-7 ≥ 10) or depression (PHQ-8 ≥ 10) before and after the COVID-19 vaccine became universally available for adults in the U.S. Participants belonged to the Communities, Households, and SARS-CoV-2 Epidemiology Cohort (CHASING COVID), a national longitudinal study. Our analytic population included 4,832 participants who reported vaccination status from December 2020 to December 2021 with follow-up outcomes assessed through March 2022. We emulated a hypothetical randomized experiment, a target trial, to estimate the effect of COVID-19 vaccination on symptoms of anxiety or depression. Before vaccines were universally available, participants who were vaccinated versus not had significantly lower adjusted odds of symptoms of moderate or severe anxiety (aOR: 0.79; 95% CI: 0.70-0.89). In the universal vaccine era, vaccination was associated with marginally higher adjusted odds of symptoms of moderate or severe anxiety (aOR: 1.23; 95% CI: 1.00-1.50). Vaccination did not influence subsequent moderate or severe depressive symptoms in the preuniversal vaccine era (aOR: 0.92; 95% CI: 0.82-1.03) or universal vaccine era (aOR: 1.11; 95% CI: 0.91-1.36). Research into the longitudinal relationship between COVID-19 vaccination and symptoms of depression and anxiety is warranted, with a focus on advancing understanding of potential mediators on the pathway between vaccination and mental health as well as modifiable factors, such as vaccine hesitancy or vaccine beliefs, that may help identify populations for whom vaccination may be particularly beneficial to their mental health.

Low-Level Visual Features of Window Views Contribute to Perceived Naturalness and Mental Health Outcomes

Previous studies have shown that natural window views are beneficial for mental health, but it is still unclear which specific features constitute a 'natural' window view. On the other hand, studies on image analysis found that low-level visual features (LLVFs) are associated with perceived naturalness, but mainly conducted experiments with brief stimulus presentations. In this study, research on the effects of window views on mental health was combined with the detailed analysis of LLVFs. Healthy adults rated window views from their home and sent in photographs of those views for analysis. Content validity of the 'ecological' view assessment was evaluated by checking correlations of LLVFs with window view ratings. Afterwards, it was explored which of the LLVFs best explained variance in perceived percentage of nature and man-made elements, and in ratings of view quality. Criterion validity was tested by investigating which variables were associated with negative affect and impulsive decision-making. The objective and subjective assessments of nature/sky in the view were aligned but objective brightness was unreliable. The perceived percentage of nature was significantly explained by green pixel ratio, while view quality was associated with fractals, saturation, sky pixel ratio and straight edge density. The higher subjective brightness of rooms was associated with a lower negative affect, whereas results for impulsive decision-making were inconsistent. The research highlights the validity to apply LLVFs analysis to ecological window views. For affect, subjective brightness seemed to be more relevant than LLVFs. For impulsive decision-making, performance context needs to be controlled in future studies.

Heat and hospital admission via the emergency department for people with intellectual disability, autism, and mental disorders in South Korea: a nationwide, time-stratified, case-crossover study

BACKGROUND

Given the anticipated increase in ambient temperature due to climate change, the hazardous effects of heat on health have been extensively studied; however, its impact on people with intellectual disability, autism, and mental illness is largely unknown. We aimed to estimate the association between heat and hospitalisation through the emergency department (ED) among people with these mental disorders.

METHODS

In this nationwide study, we used data from the National Health Insurance Database (NHID) of the National Health Insurance Service, the single universal insurer in South Korea, the claims data for which is based on the ICD-10. We included individuals with identified intellectual disability, autism, and mental disorders (including schizophrenia, bipolar disorder, recurrent depressive disorder, schizoaffective disorder and persistent obsessive-compulsive disorder, Tourette's disorder, and narcolepsy) and we established two control groups of people without these disorders: one including 1 million systematically sampled individuals, and one matched to the cohort based on sex, age, and income group. Data on hospital admission via the ED were obtained from the NHID, including the primary cause of admission and corresponding medical costs, for the warm season (June-September) of the period 2006-2021. We used the Google Earth Engine with the ERA5-Land dataset to collect data on the daily mean temperature. We applied a time-stratified case-crossover design using a distributed lag non-linear model and performed a conditional logistic regression. The risk ratio was estimated as the odds ratio (OR) with calculated odds at the 99th percentile temperature compared with that at the local 75th percentile temperature. We did not include people with lived experience of mental illness in this study.

FINDINGS

Of the 456 946 people with intellectual disability, autism, or mental disorder in the NHID records, 99 845 were admitted to the ED, including 59 821 (59·9%) males and 40 024 (40·1%) females, and including 29 192 people with intellectual disability, 1428 people with autism, and 69 225 people with mental disorders. We were not able to collect data on ethnicity. The mean age at ED admission was 42·1 years (SD 17·9, range 0-102) for people with intellectual disability, 18·6 years (SD 10·4, range 1-72) for people with autism, and 50·8 years (SD 11·9, range 2-94) for people with mental disorders. The heat OR (odds at the 99th percentile vs 75th percentile of temperature) of ED admission was 1·23 (95% CI 1·11-1·36) for intellectual disability, 1·06 (0·68-1·63) for autism, and 1·20 (1·12-1·29) for mental disorders. People with intellectual disability, female individuals, people living in rural areas, or those with a low-income status were at increased risk of ED admission due to heat. The risk of ED admission due to genitourinary diseases was higher than that from other causes. Annual increase in medical costs attributable to heat among people with intellectual disability, autism, and mental disorders was US$ 224 970 per 100 000 person-years (95% empirical CI 139 784-305 770).

INTERPRETATION

People with intellectual disability, autism, and mental disorders should be included in groups considered at a high-risk for heat exposure, and heat adaptation policies should be implemented with consideration of these groups and their needs.

FUNDING

The National Research Foundation of Korea, Korean Ministry of Environment, and Korean Ministry of Education.

TRANSLATION

For the Korean translation of the abstract see Supplementary Materials section.

Higher Risk of Psychiatric Disorders in Children With Febrile Seizures: A Nationwide Cohort Study in Taiwan

BACKGROUND

Febrile seizures occur commonly in children aged between six months and six years. A previous Danish study found a positive correlation between febrile seizures and the overall incidence of psychiatric disorders. This population-based nationwide observational study was conducted to investigate the association between febrile seizures and different psychiatric disorders in Taiwan and the associated risk factors.

METHODS

This cohort study used data from the National Health Insurance Research Database in Taiwan-a nationwide claims database covering >99% of the Taiwanese population. The study period was from January 2000 to December 2015; the overall median follow-up time was 11.04 ± 10.95 years. Overall, 2464 children with febrile seizures diagnosed between 2000 and 2015 met the inclusion criteria, and 7392 children without febrile seizures matched by index year, age, and sex were included in the control cohorts. Febrile seizures and psychiatric disorders were measured as the exposure and main outcomes, respectively.

RESULTS

Children with febrile seizures (n = 2463) were at a high risk of psychiatric disorders (adjusted hazard ratio, 4.70; 95% confidence interval [CI], 2.44 to 7.30; P < 0.001). The risk for anxiety was the highest (adjusted hazard ratio, 21.92; 95% CI, 11.40 to 34.05; P < 0.001).

CONCLUSIONS

When treating children with febrile seizures, particular attention should be paid to the symptoms of psychiatric disorders, as early referral may be beneficial for these children.

Immediate and delayed effects of environmental temperature on schizophrenia admissions in Liuzhou, China, 2013-2020: a time series analysis

This study aimed to investigate the associations between environmental temperature and schizophrenia admissions in Liuzhou, China. A Poisson generalized linear model combined with a distributed lag nonlinear model was used to analyze the effects of daily mean temperature on schizophrenia admissions from 2013 to 2020 in Liuzhou. Additionally, subgroup analyses were conducted to investigate possible modifications stratified by gender, marital status, and age. In this study, 10,420 schizophrenia admissions were included. The relative risks of schizophrenia admissions increased as the temperature rose, and the lag effects of high temperature on schizophrenia admissions were observed when the daily mean temperature reached 21.65°C. The largest single effect was observed at lag0, while the largest cumulative effect was observed at lag6. The single effects of high temperatures on schizophrenia admissions were statistically significant in both males and females, but the cumulative effects were statistically significant only in males, with the greatest effect at lag0-7. The single effect of high temperatures on admissions for unmarried schizophrenics was greatest at lag5, while the maximum cumulative effect for unmarried schizophrenia was observed at lag0-7. The single effects of high temperatures on schizophrenia admissions were observed in those aged 0-20, 21-40, and 41-60. The cumulative effects for schizophrenics aged 21-40 were observed from lag0-3 to lag0-7, with the maximum effect at lag0-7. In conclusion, the risk of schizophrenia admissions increased as the environmental temperature increased. The schizophrenics who were unmarried appeared to be more vulnerable to the single and cumulative effects of high temperature.

The relationship between hot temperatures and hospital admissions for psychosis in adults diagnosed with schizophrenia: A case-crossover study in Quebec, Canada

INTRODUCTION

Some studies have found hot temperatures to be associated with exacerbations of schizophrenia, namely psychoses. As climate changes faster in Northern countries, our understanding of the association between temperature and hospital admissions (HA) for psychosis needs to be deepened.

OBJECTIVES

1) Among adults diagnosed with schizophrenia, measure the relationship between mean temperatures and HAs for psychosis during summer. 2) Determine the influence of individual and ecological characteristics on this relationship.

METHODS

A cohort of adults diagnosed with schizophrenia (n = 30,649) was assembled using Quebec's Integrated Chronic Disease Surveillance System (QICDSS). The follow-up spanned summers from 2001 to 2019, using hospital data from the QICDSS and meteorological data from the National Aeronautics and Space Administration's (NASA) Daymet database. In four geographic regions of the province of Quebec, a conditional logistic regression was used for the case-crossover analysis of the relationship between mean temperatures (at lags up to 6 days) and HAs for psychosis using a distributed lag non-linear model (DLNM). The analyses were adjusted for relative humidity, stratified according to individual (age, sex, and comorbidities) and ecological (material and social deprivation index and exposure to green space) factors, and then pooled through a meta-regression.

RESULTS

The statistical analyses revealed a statistically significant increase in HAs three days (lag 3) after elevated mean temperatures corresponding to the 90th percentile relative to a minimum morbidity temperature (MMT) (OR 1.040; 95% CI 1.008-1.074), while the cumulative effect over six days was not statistically significant (OR 1.052; 95% IC 0.993-1.114). Stratified analyses revealed non statistically significant gradients of increasing HAs relative to increasing material deprivation and decreasing green space levels.

CONCLUSIONS

The statistical analyses conducted in this project showed the pattern of admissions for psychosis after hot days. This finding could be useful to better plan health services in a rapidly changing climate.

Association between heat and hospital admissions in people with disabilities in South Korea: a nationwide, case-crossover study

BACKGROUND

Despite extensive findings on the hazardous impacts of environmental heat exposure, little is known about the effect on people with disabilities. This study aimed to estimate the association between environmental heat exposure and emergency department admissions for people with disabilities compared with people without disabilities.

METHODS

In this nationwide, case-crossover study, we linked data on emergency department admissions (cases) for any cause in the warm season in South Korea from the Korean National Health Insurance Service (NHIS)-National Sample Cohort database (a nationally representative database of 1 million systematically sampled beneficiaries covering all ages) from Jan 1, 2002, to Dec 31, 2019, and short-term daily mean temperature exposure (measured via Google Earth Engine at a 9 km spatial grid, aggregated to district). We defined beneficiaries with disabilities as those who were registered as disabled in the NHIS; disabilities included in our study were physical disability, brain lesion disorders, blindness or vision loss, and deafness or hearing loss. Other types of disability were not included for confidentiality reasons. A time-stratified case-crossover design, in which participants served as their own control, was used with conditional logistic regression to estimate the association between heat and emergency department admissions in people with and without disabilities.

FINDINGS

23 792 emergency department admissions were recorded for 59 527 people with disabilities. Of these 23 792 admissions, 10 234 (43·0%) individuals were female and 13 558 (57·0%) were male. The odds ratio (OR) of emergency department admissions associated with heat (99th temperature percentile vs 75th percentile) was 1·15 (95% CI 1·07-1·24) in people with disabilities and 1·06 (1·04-1·09) in people without disabilities. The annual excess number of emergency department admissions attributable to heat per 100 000 persons-years was 27·81 admissions (95% CI 9·20-45·69) and excess medical costs were US$638 739·47 (95% CI 201 900·12-1 059 641·87) in people with disabilities; these values were more than four times that of the non-disabled population. People with brain lesion disorders, people with severe physical disabilities, female individuals, and those aged 65 years or older showed higher heat risks. The risks of emergency department admissions due to mental disorder (1·89, 95% CI 1·18-3·00) and respiratory diseases (1·34, 1·06-1·70) also showed higher heat risks than for the other two analysed causes of admission (cardiovascular and genitourinary diseases).

INTERPRETATION

Heat was associated with increased risk of emergency department admissions for people with and without disabilities, but the risk appeared to be higher for those with disabilities. These results can inform policy makers when establishing action plans for people with disabilities.

FUNDING

National Research Foundation of Korea, the South Korean Ministry of Environment, and the South Korean Ministry of Education.

Climate change and health: rethinking public health messaging for wildfire smoke and extreme heat co-exposures

With the growing climate change crisis, public health agencies and practitioners must increasingly develop guidance documents addressing the public health risks and protective measures associated with multi-hazard events. Our Policy and Practice Review aims to assess current public health guidance and related messaging about co-exposure to wildfire smoke and extreme heat and recommend strengthened messaging to better protect people from these climate-sensitive hazards. We reviewed public health messaging published by governmental agencies between January 2013 and May 2023 in Canada and the United States. Publicly available resources were eligible if they discussed the co-occurrence of wildfire smoke and extreme heat and mentioned personal interventions (protective measures) to prevent exposure to either hazard. We reviewed local, regional, and national governmental agency messaging resources, such as online fact sheets and guidance documents. We assessed these resources according to four public health messaging themes, including (1) discussions around vulnerable groups and risk factors, (2) symptoms associated with these exposures, (3) health risks of each exposure individually, and (4) health risks from combined exposure. Additionally, we conducted a detailed assessment of current messaging about measures to mitigate exposure. We found 15 online public-facing resources that provided health messaging about co-exposure; however, only one discussed all four themes. We identified 21 distinct protective measures mentioned across the 15 resources. There is considerable variability and inconsistency regarding the types and level of detail across described protective measures. Of the identified 21 protective measures, nine may protect against both hazards simultaneously, suggesting opportunities to emphasize these particular messages to address both hazards together. More precise, complete, and coordinated public health messaging would protect against climate-sensitive health outcomes attributable to wildfire smoke and extreme heat co-exposures.

Health risks from extreme heat in China: Evidence from health insurance

Global warming has accentuated the effects of extreme heat on health. Health insurance, functioning as a risk management tool, has the potential to alleviate these impacts. Consequently, this paper investigates the correlation between extreme heat events and the demand for health insurance in China. Using data from the China Health and Nutrition Survey, we have observed a substantial increase in the likelihood of residents purchasing health insurance during extreme heat events. To be specific, for every extra day of extreme heat events annually, there is a 0.3% increase in the probability of purchasing health insurance. This effect is not uniform across different demographic groups. It is particularly pronounced among middle-aged and elderly individuals, rural residents, those with lower educational levels, higher income brackets, and individuals residing in underprivileged areas with limited access to green spaces and healthcare facilities. Furthermore, our study indicates that the increased frequency of extreme heat events not only impacts individuals' physical health but also triggers negative emotions, which in turn drive risk-averse behavior related to health insurance purchases. These findings carry substantial policy implications for mitigating the economic consequences of climate change.

Residential greenspace and major depression among older adults living in urban and suburban areas with different climates across the United States

BACKGROUND AND AIM

Residential greenspace could alleviate depression - a leading cause of disability. Fewer studies of depression and greenspace have considered major depression, and, to our knowledge, none have considered how climate, which determines vegetation abundance and type, may change the impacts of greenspace. Our aim was to investigate whether residential greenspace is associated with major depression among older adults and explore effect modification by climate.

METHODS

We used biennial interviews between 2008 and 2016 from the Health and Retirement Study. We calculated greenness within walking distance of home addresses as the maximum NDVI for the year of each participant interview averaged within a 1 km buffer. Reflecting clinical criteria, a score of ≥5 on the CIDI-SF indicated major depression in the preceding 12-months. We characterized climate using Köppen-Geiger classifications. To estimate prevalence ratios, we used Poisson regression. Our models adjusted for sociodemographic characteristics, geography, annual sunshine, and bluespace.

RESULTS

The 21,611 eligible participants were 65 ± 10 years old on average, 55% female, 81% White, 12% Black, 10% Hispanic/Latino, and 31% had at least a 4-year college degree. The 12-month prevalence of a major depression was 8%. In adjusted models, more residential greenspace was associated with a lower prevalence of major depression (prevalence ratio per IQR, 0.91; 95% CI, 0.84 to 0.98). There was evidence of effect modification by climate (P forinteraction, 0.062). We observed stronger associations in tropical (prevalence ratio per IQR 0.69; 95% CI, 0.47 to 1.01) and cold (prevalence ratio per IQR, 0.83; 95% CI, 0.74 to 0.93) climates compared to arid (prevalence ratio per IQR 0.99; 95% CI, 0.90 to 1.09) and temperate (prevalence ratio per IQR 0.98; 95% CI, 0.86 to 1.11) climates.

CONCLUSIONS

Residential greenspace may help reduce major depression. However, climate may influence how people benefit from greenspace.

Self-harm and interpersonal violence due to high temperature from the global burden of disease study 2019: A 30-year assessment

BACKGROUND

The impact of global warming on health due to climate change is increasingly studied, but the global burden of self-harm and interpersonal violence attributable to high temperature is still limited. This study aimed to systematically assess the burden of self-harm and interpersonal violence attributable to high temperature globally or by region and climate zone from 1990 to 2019.

METHODS

We obtained the global, regional, and national deaths, disability-adjusted life years (DALYs), age-standardized mortality rates (ASMR), and age-standardized disability-adjusted life year rates (ASDR) of self-harm and interpersonal violence due to high temperature from 1990 to 2019 through the Global Burden of Disease Study (GBD) 2019. The burden of self-harm and interpersonal violence due to high temperature was estimated by age, sex, climate zone, the socio-demographic index (SDI), and the healthcare access and quality index (HAQ). Average annual percentage changes (AAPCs) in ASMR and ASDR were calculated for 1990-2019 using the Joinpoint model.

RESULTS

From 1990 to 2019, the global deaths and DALYs related to self-harm and interpersonal violence due to high temperature increased from 20,002 (95% UI, 9243 to 41,928) and 1,107,216 (95% UI, 512,062 to 2,319,477) to 26,459 (95% UI, 13,574 to 47,265) and 1,382,487 (95% UI, 722,060 to 2,474,441), respectively. However, the ASMR and ASDR showed varying degrees of decreasing trends, with decreases of 13.36% and 12.66%, respectively. The ASMR was high and declining in low and low-middle SDI regions, particularly in tropical and subtropical regions. In addition, SDI and HAQ index were negatively correlated with ASMR in 204 countries and regions.

CONCLUSIONS

The global burden of self-harm and interpersonal violence attributed to high temperature has decreased over the past 30 years, but the number of deaths and DALYs continues to rise. Climate change continues to make heat stress a significant risk factor for self-harm and interpersonal violence worldwide.

Climate stress and anxiety, environmental context, and civic engagement: A nationally representative study

There is increasing recognition that people are experiencing stress and anxiety around climate change, and that this climate stress/anxiety may be associated with more pro-environmental behavior. However, less is known about whether people's own environmental exposures affect climate stress/anxiety or the relationship between climate stress/anxiety and civic engagement. Using three waves of survey data (2020-2022) from the nationally representative Tufts Equity in Health, Wealth, and Civic Engagement Study of US adults (n = 1071), we assessed relationships among environmental exposures (county-level air pollution, greenness, number of toxic release inventory sites, and heatwaves), self-reported climate stress/anxiety, and civic engagement measures (canvasing behavior, collaborating to solve community problems, personal efficacy to solve community problems, group efficacy to solve community problems, voting behavior). Most participants reported experiencing climate stress/anxiety (61%). In general, the environmental exposures we assessed were not significantly associated with climate stress/anxiety or civic engagement metrics, but climate stress/anxiety was positively associated with most of the civic engagement outcomes (canvassing, personal efficacy, group efficacy, voter preference). Our results support the growing literature that climate stress/anxiety may spur constructive civic action, though do not suggest a consistent relationship between adverse environmental exposures and either climate stress/anxiety or civic engagement. Future research and action addressing the climate crisis should promote climate justice by ensuring mental health support for those who experience climate stress anxiety and by promoting pro-environmental civic engagement efforts.

Long-term effect of extreme temperature on cognitive function of middle-aged and older adults in China

BACKGROUND

Several studies have explored the association between temperature and cognitive function. However, few studies have examined the effect of extreme temperature on cognitive function. In this study, we aimed to quantify the long-term effect of extreme temperature (e.g., heat waves, cold spells, and hot night excess (HNE)) on cognitive performance in middle-aged and older people in China.

METHOD

We investigated 7915 aged >45 years people from the China Health and Retirement Longitudinal Study (CHARLS), surveyed in 2011 and 2015. A structured questionnaire was utilized to assess cognitive function, including four dimensions: episodic memory, attention, orientation, and visuo-construction. Hourly ambient temperature from the ERA5-Land datasets were used to calculate variables indicating extreme temperature. We performed difference-in-difference (DID) models to assess the potential causal relationship between extreme temperature and cognitive function.

RESULTS

Non-linear analyses suggested that both sustained increases in temperature and excessive variability in temperature increased the risk of cognitive decline. Meanwhile, we observed the extra risk of global cognitive function decline was 2.3% (95% Confidence interval (95% CI): 0.2%, 4.4%) for heat waves (one unit increase) and 5.9% (95% CI: 0.6%, 11.6%) for HNE (one unit increase), while the association for cold spells was insignificant. Two cognitive dimensions, episodic memory and visuo-construction, were sensitive to these two heat-related factors.

CONCLUSION

Extreme temperature was inversely related to cognitive performance in middle-aged and older adults, which was substantial for heat waves and HNE particularly. The effect size varied by cognitive dimensions.

Climate Change and Human Health in Africa in Relation to Opportunities to Strengthen Mitigating Potential and Adaptive Capacity: Strategies to Inform an African "Brains Trust"

Background

Africa faces diverse and complex population/human health challenges due to climate change. Understanding the health impacts of climate change in Africa in all its complexity is essential for implementing effective strategies and policies to mitigate risks and protect vulnerable populations. This study aimed to outline the major climate change-related health impacts in Africa in the context of economic resilience and to seek solutions and provide strategies to prevent or reduce adverse effects of climate change on human health and well-being in Africa.

Methods

For this narrative review, a literature search was conducted in the Web of Science, Scopus, CAB Abstracts, MEDLINE and EMBASE electronic databases. We also searched the reference lists of retrieved articles for additional records as well as reports. We followed a conceptual framework to ensure all aspects of climate change and health impacts in Africa were identified.

Results

The average temperatures in all six eco-regions of Africa have risen since the early twentieth century, and heat exposure, extreme events, and sea level rise are projected to disproportionately affect Africa, resulting in a larger burden of health impacts than other continents. Given that climate change already poses substantial challenges to African health and well-being, this will necessitate significant effort, financial investment, and dedication to climate change mitigation and adaptation. This review offers African leaders and decision-makers data-driven and action-oriented strategies that will ensure a more resilient healthcare system and safe, healthy populations-in ways that contribute to economic resiliency.

Conclusions

The urgency of climate-health action integrated with sustainable development in Africa cannot be overstated, given the multiple economic gains from reducing current impacts and projected risks of climate change on the continent's population health and well-being. Climate action must be integrated into Africa's development plan to meet the Sustainable Development Goals, protect vulnerable populations from the detrimental effects of climate change, and promote economic development.

Impacts of compounding drought and heatwave events on child mental health: insights from a spatial clustering analysis

BACKGROUND

Concurrent heatwave and drought events may have larger health impacts than each event separately; however, no US-based studies have examined differential mental health impacts of compound drought and heatwave events in pediatric populations.

OBJECTIVE

To examine the spatial patterns of mood disorders and suicide-related emergency department (ED) visits in children during heatwave, drought, and compound heatwave and drought events. We tested whether the occurrence of compound heatwave and drought events have a synergistic (multiplicative) effect on the risk of mental health related outcomes in children as compared to the additive effect of each individual climate hazard. Lastly, we identified household and community-level determinants of geographic variability of high psychiatric burden.

METHODS

Daily counts of psychiatric ED visits in North Carolina from 2016 to 2019 (May to Sept) for pediatric populations were aggregated at the county scale. Bernoulli cluster analyses identified high-risk spatial clusters of psychiatric morbidity during heatwave, drought, or compound heatwave and drought periods. Multivariate adaptive regression models examined the individual importance of household and community-level determinants in predicting high-risk clustering of mood disorders or suicidality across the three climate threats.

RESULTS

Results showed significant spatial clustering of suicide and mood disorder risks in children during heatwave, drought, and compound event periods. Periods of drought were associated with the highest likelihood of spatial clustering for suicide and mood disorders, where the risk of an ED visit was 4.48 and 6.32 times higher, respectively, compared to non-drought periods. Compounding events were associated with a threefold increase in both suicide and mood disorder-related ED visits. Community and household vulnerability factors that most contributed to spatial clustering varied across climate hazards, but consistent determinants included residential segregation, green space availability, low English proficiency, overcrowding, no broadband access, no vehicle access, housing vacancy, and availability of housing units.

CONCLUSION

Findings advance understanding on the locations of vulnerable pediatric populations who are disproportionately exposed to compounding climate stressors and identify community resilience factors to target in public health adaptation strategies.

Seasonality of presentation and birth in catatonia

BACKGROUND

Catatonia is a neuropsychiatric syndrome associated with both psychiatric disorders and medical conditions. Understanding of the pathophysiology of catatonia remains limited, and the role of the environment is unclear. Although seasonal variations have been shown for many of the disorders underlying catatonia, the seasonality of this syndrome has not yet been adequately explored.

METHODS

Clinical records were screened to identify a cohort of patients suffering from catatonia and a control group of psychiatric inpatients, from 2007 to 2016 in South London. In a cohort study, the seasonality of presentation was explored fitting regression models with harmonic terms, while the effect of season of birth on subsequent development of catatonia was analyzed using regression models for count data. In a case-control study, the association between month of birth and catatonia was studied fitting logistic regression models.

RESULTS

In total, 955 patients suffering from catatonia and 23,409 controls were included. The number of catatonic episodes increased during winter, with a peak in February. Similarly, an increasing number of cases was observed during summer, with a second peak in August. However, no evidence for an association between month of birth and catatonia was found.

CONCLUSIONS

The presentation of catatonia showed seasonal variation in accordance with patterns described for many of the disorders underlying catatonia, such as mood disorders and infections. We found no evidence for an association between season of birth and risk of developing catatonia. This may imply that recent triggers may underpin catatonia, rather than distal events.