Evaluation of individual and area-level factors as modifiers of the association between warm-season temperature and pediatric asthma morbidity in Atlanta, GA

Heat Metrics and Maternal-Child Health Diagnoses in Emergency Departments in the United States: A Scoping Review

OBJECTIVE

To summarize current research on associations between heat metrics and emergency department discharge diagnoses for US pregnant women and children from birth to age 18 via a scoping review.

BACKGROUND

Climate change directly contributes to extreme weather conditions and environmental changes and indirectly affects health and the health care system. Pregnant women and children are believed to be more susceptible to extreme heat, but few empirical studies have been conducted evaluating effects of heat metrics on these populations.

METHODS

Ovid MEDLINE, CIHAHL, SCOPUS, Web of Science, JSTOR, and PsycINFO databases were searched using a combination of key words.

RESULTS

Twelve studies were selected for this review. In pregnant women, positive associations were found between mean daily temperature and multiple subtypes of pregnancy complications, including threatened or spontaneous abortion, renal diseases, infectious diseases, diabetes, and hypertension. In children, positive associations were found with all-cause diagnoses; asthma; dehydration; electrolyte disorders; heat-related illness; infection; endocrine, nutritional, and metabolic diseases; injury; and otitis media and external emergency department discharge diagnoses and temperature or heatwave versus non-heatwave.

CONCLUSION

By tracking associations between maternal-child emergency department discharge diagnoses and various heat metrics, researchers can contribute to better clinical practices that promote environmental justice and climate resilience.

How climate change degrades child health: A systematic review and meta-analysis

BACKGROUND

Children are more vulnerable than adults to climate-related health threats, but reviews examining how climate change affects human health have been mainly descriptive and lack an assessment of the magnitude of health effects children face. This is the first systematic review and meta-analysis that identifies which climate-health relationships pose the greatest threats to children.

OBJECTIVES

We reviewed epidemiologic studies to analyse various child health outcomes due to climate change and identify the relationships with the largest effect size. We identify population-specific risks and provide recommendations for future research.

METHODS

We searched four large online databases for observational studies published up to 5 January 2023 following PRISMA (systematic review) guidelines. We evaluated each included study individually and aggregated relevant quantitative data. We used quantitative data in our meta-analysis, where we standardised effect sizes and compared them among different groupings of climate variables and health outcomes.

RESULTS

Of 1301 articles we identified, 163 studies were eligible for analysis. We identified many relationships between climate change and child health, the strongest of which was increasing risk (60 % on average) of preterm birth from exposure to temperature extremes. Respiratory disease, mortality, and morbidity, among others, were also influenced by climate changes. The effects of different air pollutants on health outcomes were considerably smaller compared to temperature effects, but with most (16/20 = 80 %) pollutant studies indicating at least a weak effect. Most studies occurred in high-income regions, but we found no geographical clustering according to health outcome, climate variable, or magnitude of risk. The following factors were protective of climate-related child-health threats: (i) economic stability and strength, (ii) access to quality healthcare, (iii) adequate infrastructure, and (iv) food security. Threats to these services vary by local geographical, climate, and socio-economic conditions. Children will have increased prevalence of disease due to anthropogenic climate change, and our quantification of the impact of various aspects of climate change on child health can contribute to the planning of mitigation that will improve the health of current and future generations.

Associations of pollen and cardiovascular disease morbidity in Atlanta during 1993-2018

Background

Pollen exposure is associated with substantial respiratory morbidity, but its potential impact on cardiovascular disease (CVD) remains less understood. This study aimed to investigate the associations between daily levels of 13 pollen types and emergency department (ED) visits for eight CVD outcomes over a 26-year period in Atlanta, GA.

Methods

We acquired pollen data from Atlanta Allergy & Asthma, a nationally certified pollen counting station, and ED visit data from individual hospitals and the Georgia Hospital Association. We performed time-series analyses using quasi-Poisson distributed lag models, with primary analyses assessing 3-day (lag 0-2 days) pollen levels. Models controlled for temporally varying covariates, including air pollutants.

Results

During 1993-2018, there were 1,573,968 CVD ED visits. Most pairwise models of the 13 pollen types and eight CVD outcomes showed no association, with a few exceptions potentially due to chance.

Conclusion

We found limited evidence of the impact of pollen on cardiovascular morbidity in Atlanta. Further study on pollen exposures in different climactic zones and exploration of pollen-pollution mixture effects is warranted.

The Sleep Environment, Napping, and Sleep Outcomes among Urban Children With and Without Asthma

OBJECTIVES

Children with asthma living in U.S. urban neighborhoods experience increased risk for asthma morbidity and poor sleep outcomes. In addition to asthma, environmental factors (e.g. noise, uncomfortable temperature, light exposure) related to urban poverty may disturb children's sleep. This study examined the association between environmental factors and sleep outcomes among urban children with and without asthma, and whether napping underlies the environment-sleep link. Additionally, the study tested whether these associations differed by health status (i.e. asthma) or race/ethnicity.

METHOD

Participants included urban children aged 7-9 years with (N = 251) and without (N = 130) asthma from Latino, Black, or non-Latino White (NLW) background. Caregivers reported sleep environmental factors and naps. Sleep duration, efficiency, and nightly awakenings were assessed via actigraphy.

RESULTS

Regardless of health status, frequent exposure to noise and light was associated with poorer sleep outcomes only among Latino children. In the full sample with and without asthma, noise exposure during nighttime sleep was related to more frequent daytime naps, which were linked to shorter nighttime sleep duration.

CONCLUSIONS

Exposure to noise and light may play a particularly influential role in shaping urban children's sleep outcomes. Racial/ethnic differences and the potential mediating role of napping in this environment-sleep association may inform tailored interventions.

The role of insurance status in the association between short-term temperature exposure and myocardial infarction hospitalizations in New York State

Myocardial infarction (MI) is a leading cause of morbidity and mortality in the United States and its risk increases with extreme temperatures. Climate change causes variability in weather patterns, including extreme temperature events that disproportionately affect socioeconomically disadvantaged communities. Many studies on the health effects of extreme temperatures have considered community-level socioeconomic disadvantage.

Objectives

To evaluate effect modification of the relationship between short-term ambient temperature and MI, by individual-level insurance status (insured vs. uninsured).

Methods

We identified MI hospitalizations and insurance status across New York State (NYS) hospitals from 1995 to 2015 in the New York Department of Health Statewide Planning and Research Cooperative System database, using International Classification of Diseases codes. We linked short-term ambient temperature (averaging the 6 hours preceding the event [MI hospitalization]) or nonevent control period in patient residential zip codes. We employed a time-stratified case-crossover study design for both insured and uninsured strata, and then compared the group-specific rate ratios.

Results

Over the study period, there were 1,095,051 primary MI admissions, 966,475 (88%) among insured patients. During extremely cold temperatures (<5.8 °C) insured patients experienced reduced rates of MI; this was not observed among the uninsured counterparts. At warmer temperatures starting at the 65th percentile (15.7 °C), uninsured patients had higher rates than insured patients (e.g., for a 6-hour pre-event average temperature increase from the median to the 75th percentile, the rate of MI increased was 2.0% [0.0%-4.0%] higher in uninsured group).

Conclusions

Uninsured individuals may face disproportionate rates of MI hospitalization during extreme temperatures.

Protecting Children's Health: Asthma and Climate Change

ABSTRACT

Children are particularly vulnerable to the impacts of climate change. Their lungs are developing, making children with asthma especially susceptible to temperature extremes, variations in precipitation, poor air quality, and changes in pollen and flora. Structural and social determinants of health, such as racism and poverty, that disproportionately affect children of color are linked to higher rates of asthma and negative effects of climate change. These factors lead to increased absences from school and social activities, loss of work for caregivers, and increased health care costs, thus negatively affecting children, their families, and the greater community. Nurses must support caregivers and children to link climate change to asthma care, be involved in health education; climate change mitigation and adaptation strategies and policies; and develop the evidence to address climate change and asthma strategies. We address the impacts of climate change on children with asthma and nursing adaptation responses.

Pollen and asthma morbidity in Atlanta: A 26-year time-series study

BACKGROUND

Compared to many environmental risk factors, the relationship between pollen and asthma is understudied, including how associations may differ by pollen type and between subgroups, and how associations may be changing over time.

OBJECTIVES

We evaluated the association between ambient pollen concentrations and emergency department (ED) visits for asthma and wheeze in Atlanta, Georgia during 1993-2018. We estimated overall associations for 13 individual pollen taxa, as well as associations by decade, race, age (5-17, 18-64, 65+), and insurance status (Medicaid vs non-Medicaid).

METHODS

Speciated pollen data were acquired from Atlanta Allergy & Asthma, a nationally certified pollen counting station. ED visit data were obtained from individual hospitals and from the Georgia Hospital Association. We performed time-series analyses using quasi-Poisson distributed lag models, with primary analyses assessing 3-day (lag 0-2 days) pollen levels. Models controlled for day of week, holidays, air temperature, month, year, and month-by-year interactions.

RESULTS

From 1993 to 2018, there were 686,259 ED visits for asthma and wheeze in the dataset, and the number of ED visits increased over time. We observed positive associations of asthma and wheeze ED visits with nine of the 13 pollen taxa: trees (maple, birch, pine, oak, willow, sycamore, and mulberry), two weeds (nettle and pigweed), and grasses. Rate ratios indicated 1-8% increases in asthma and wheeze ED visits per standard deviation increases in pollen. In general, we observed stronger associations in the earliest period (1993-2000), in younger people, and in Black patients; however, results varied by pollen taxa.

CONCLUSIONS

Some, but not all, types of pollen are associated with increased ED visits for asthma/wheeze. Associations are generally higher in Black and younger patients and appear to have decreased over time.

Envisioning environmental equity: climate change, health, and racial justice

Climate change has a broad range of health impacts and tackling climate change could be the greatest opportunity for improving global health this century. Yet conversations on climate change and health are often incomplete, giving little attention to structural discrimination and the need for racial justice. Racism kills, and climate change kills. Together, racism and climate change interact and have disproportionate effects on the lives of minoritised people both within countries and between the Global North and the Global South. This paper has three main aims. First, to survey the literature on the unequal health impacts of climate change due to racism, xenophobia, and discrimination through a scoping review. We found that racially minoritised groups, migrants, and Indigenous communities face a disproportionate burden of illness and mortality due to climate change in different contexts. Second, this paper aims to highlight inequalities in responsibility for climate change and the effects thereof. A geographical visualisation of responsibility for climate change and projected mortality and disease risk attributable to climate change per 100 000 people in 2050 was conducted. These maps visualise the disproportionate burden of illness and mortality due to climate change faced by the Global South. Our third aim is to highlight the pathways through which climate change, discrimination, and health interact in most affected areas. Case studies, testimony, and policy analysis drawn from multidisciplinary perspectives are presented throughout the paper to elucidate these pathways. The health community must urgently examine and repair the structural discrimination that drives the unequal impacts of climate change to achieve rapid and equitable action.

Asthma triggered by extreme temperatures: From epidemiological evidence to biological plausibility

BACKGROUND

There is rapidly growing evidence indicating that extreme temperature is a crucial trigger and potential activator of asthma; however, the effects of extreme temperature on asthma are inconsistently reported and the its potential mechanisms remain undefined.

OBJECTIVES

This review aims to estimate the impacts of extreme heat, extreme cold, and temperature variations on asthma by systematically summarizing the existing studies from epidemiological evidence to biological plausibility.

METHODS

We conducted a systematic search in PubMed, Embase, and Web of Science from inception to June 30, 2022, and we retrieved articles of epidemiology and biological studies which assessed associations between extreme temperatures and asthma. This protocol was registered with PROSPERO (CRD42021273613).

RESULTS

From 12,435 identified records, 111 eligible studies were included in the qualitative synthesis, and 37 articles were included in the meta-analysis (20 for extreme heat, 16 for extreme cold, and 15 for temperature variations). For epidemiological evidence, we found that the synergistic effects of extreme temperatures, indoor/outdoor environments, and individual vulnerabilities are important triggers for asthma attacks, especially when there is extreme heat or cold. Meta-analysis further confirmed the associations, and the pooled relative risks for asthma attacks in extreme heat and extreme cold were 1.07 (95%CI: 1.03-1.12) and 1.20 (95%CI: 1.12-1.29), respectively. Additionally, this review discussed the potential inflammatory mechanisms behind the associations between extreme temperatures and asthma exacerbation, and highlighted the regulatory role of immunological pathways and transient receptor potential ion channels in asthma triggered by extreme temperatures.

CONCLUSIONS

We concluded that both extreme heat and cold could significantly increase the risk of asthma. Additionally, we proposed a potential mechanistic framework, which is important for understanding the disease pathogenesis that uncovers the complex mechanisms of asthma triggered by extreme temperatures and protects the sensitive individuals from impacts of extreme weather events and climate change.

The association of indoor heat exposure with diabetes and respiratory 9-1-1 calls through emergency medical dispatch and services documentation

BACKGROUND

People with pre-existing medical conditions, who spend a large proportion of their time indoors, are at risk of emergent morbidities from elevated indoor heat exposures. In this study, indoor heat of structures wherein exposed people received Grady Emergency Services based care in Atlanta, GA, U.S., was measured from May to September 2016.

METHOD

ology: In this case-control study, analyses were conducted to investigate the effect of indoor heat on the odds of 9-1-1 calls for diabetic (n = 90 cases) and separately, for respiratory (n = 126 cases), conditions versus heat-insensitive emergencies (n = 698 controls). Generalized Additive Models considered both linear and non-linear indoor heat and health outcome associations using thin-plate regression splines.

RESULTS

Hotter and more humid indoor conditions were non-linearly associated with an increasing likelihood of receiving emergency care for complications of diabetes and severe respiratory distress. Higher heat indices were associated with increased odds of a diabetes (odds ratio for change from 30 to 31 °C: 1.12, 95% CI: 1.08-1.16) or respiratory 9-1-1 medical call versus control (odds ratio for change from 34 to 35 °C: 1.18, 95% CI: 1.09-1.28) call. Both diabetic and respiratory distress patients were more likely to be African-American and/or have comorbidities.

CONCLUSIONS

In this study, the statistical association of indoor heat exposure with emergency morbidities (diabetic, respiratory) was demonstrated. The study also showcased the value and utility of data gathered by emergency medical dispatch and services from inaccessible private indoor sources (i.e., domiciles) for environmental health.

Association of ambient extreme heat with pediatric morbidity: a scoping review

Global climate change is leading to higher ambient temperatures and more frequent heatwaves. To date, impacts of ambient extreme heat on childhood morbidity have been understudied, although-given children's physiologic susceptibility, with smaller body surface-to-mass ratios, and many years of increasing temperatures ahead-there is an urgent need for better information to inform public health policies and clinical approaches. In this review, we aim to (1) identify pediatric morbidity outcomes previously associated with extreme heat, (2) to identify predisposing co-morbidities which may make children more susceptible to heat-related outcomes, and (3) to map the current body of available literature. A scoping review of the current full-text literature was conducted using the Arksey and O'Malley framework Int J Soc Res Methodol 8:19-32, (2015). Search terms for (1) pediatric population, (2) heat exposures, (3) ambient conditions, and (4) adverse outcomes were combined into a comprehensive PubMed and Medline literature search. Of the 1753 publications identified, a total of 20 relevant studies were ultimately selected based on selection criteria of relevance to US urban populations. Most identified studies supported positive associations between high extreme temperature exposures and heat-related illness, dehydration/electrolyte imbalance, general symptoms, diarrhea and digestion disorders, infectious diseases/infections, asthma/wheeze, and injury. Most studies found no association with renal disease, cardiovascular diseases, or diabetes mellitus. Results were mixed for other respiratory diseases and mental health/psychological disorders. Very few of the identified studies examined susceptibility to pre-existing conditions; Cystic Fibrosis was the only co-morbidity for which we found significant evidence. Further research is needed to understand the nuances of associations between extreme heat and specific outcomes-particularly how associations may vary by child age, sex, race/ ethnicity, community characteristics, and other pre-existing conditions.

Racial Disparities in Climate Change-Related Health Effects in the United States

PURPOSE OF REVIEW

Climate change is causing warming over most parts of the USA and more extreme weather events. The health impacts of these changes are not experienced equally. We synthesize the recent evidence that climatic changes linked to global warming are having a disparate impact on the health of people of color, including children.

RECENT FINDINGS

Multiple studies of heat, extreme cold, hurricanes, flooding, and wildfires find evidence that people of color, including Black, Latinx, Native American, Pacific Islander, and Asian communities are at higher risk of climate-related health impacts than Whites, although this is not always the case. Studies of adults have found evidence of racial disparities related to climatic changes with respect to mortality, respiratory and cardiovascular disease, mental health, and heat-related illness. Children are particularly vulnerable to the health impacts of climate change, and infants and children of color have experienced adverse perinatal outcomes, occupational heat stress, and increases in emergency department visits associated with extreme weather. The evidence strongly suggests climate change is an environmental injustice that is likely to exacerbate existing racial disparities across a broad range of health outcomes.

Associations between high ambient temperatures and asthma exacerbation among children in Philadelphia, PA: a time series analysis

OBJECTIVES

High ambient temperatures may contribute to acute asthma exacerbation, a leading cause of morbidity in children. We quantified associations between hot-season ambient temperatures and asthma exacerbation in children ages 0-18 years in Philadelphia, PA.

METHODS

We created a time series of daily counts of clinical encounters for asthma exacerbation at the Children's Hospital of Philadelphia linked with daily meteorological data, June-August of 2011-2016. We estimated associations between mean daily temperature (up to a 5-day lag) and asthma exacerbation using generalised quasi-Poisson distributed models, adjusted for seasonal and long-term trends, day of the week, mean relative humidity,and US holiday. In secondary analyses, we ran models with adjustment for aeroallergens, air pollutants and respiratory virus counts. We quantified overall associations, and estimates stratified by encounter location (outpatient, emergency department, inpatient), sociodemographics and comorbidities.

RESULTS

The analysis included 7637 asthma exacerbation events. High mean daily temperatures that occurred 5 days before the index date were associated with higher rates of exacerbation (rate ratio (RR) comparing 33°C-13.1°C days: 1.37, 95% CI 1.04 to 1.82). Associations were most substantial for children ages 2 to <5 years and for Hispanic and non-Hispanic black children. Adjustment for air pollutants, aeroallergens and respiratory virus counts did not substantially change RR estimates.

CONCLUSIONS

This research contributes to evidence that ambient heat is associated with higher rates of asthma exacerbation in children. Further work is needed to explore the mechanisms underlying these associations.

The Impact of Converting a Power Plant from Coal to Natural Gas on Pediatric Acute Asthma

Background and Objectives: Air pollutants play a pivotal role in the frequency and severity of asthma symptoms. As cleaner air initiatives are increasingly being implemented, it is important to appraise how these changes relate to acute pediatric asthma. The objective of this study is to evaluate the effect of a Gas and Electric Company's transition from using coal to natural gas as their fuel source on pediatric asthma-related illnesses in Louisville, KY.Methods: Data were collected for children 2-17 years old from a large regional healthcare system, for which an asthma-related primary diagnosis was present between April 1, 2013 and April 1, 2018. Using an interrupted time series design, we analyzed monthly rates of asthma-related visits to urgent care (UC) and emergency departments (ED). Segmented Poisson regression models were used to assess whether the power company's transition was associated with changes in trends of asthma-related visits.Results: There were a total of 7,735 subjects who met inclusion criteria. Prior to the complete factory transition from coal to natural gas, the mean monthly rate for asthma-related visits was 163.9. After the transition, we observed a significant decrease to a mean monthly rate of 100.3 asthma-related visits (p < 0.001). In addition, the proportion of inpatient (23.7% vs. 30.5%, p < 0.001) visits significantly increased, while ED & UC (76.3 vs. 69.5%, p < 0.001) were significantly decreased.Conclusion: Converting an electrical power plant from coal to natural gas lead to a profound and sustained decrease in pediatric acute asthma exacerbation in Louisville, KY.

Temperature-mortality relationship in North Carolina, USA: Regional and urban-rural differences

BACKGROUND

Health disparities exist between urban and rural populations, yet research on rural-urban disparities in temperature-mortality relationships is limited. As inequality in the United States increases, understanding urban-rural and regional differences in the temperature-mortality association is crucial.

OBJECTIVE

We examined regional and urban-rural differences of the temperature-mortality association in North Carolina (NC), USA, and investigated potential effect modifiers.

METHODS

We applied time-series models allowing nonlinear temperature-mortality associations for 17 years (2000-2016) to generate heat and cold county-specific estimates. We used second-stage analysis to quantify the overall effects. We also explored potential effect modifiers (e.g. social associations, greenness) using stratified analysis. The analysis considered relative effects (comparing risks at 99th to 90th temperature percentiles based on county-specific temperature distributions for heat, and 1st to 10th percentiles for cold) and absolute effects (comparing risks at specific temperatures).

RESULTS

We found null effects for heat-related mortality (relative effect: 1.001 (95% CI: 0.995-1.007)). Overall cold-mortality risk for relative effects was 1.019 (1.015-1.023). All three regions had statistically significant cold-related mortality risks for relative and absolute effects (relative effect: 1.019 (1.010-1.027) for Coastal Plains, 1.021 (1.015-1.027) for Piedmont, 1.014 (1.006-1.023) for Mountains). The heat mortality risk was not statistically significant, whereas the cold mortality risk was statistically significant, showing higher cold-mortality risks in urban areas than rural areas (relative effect for heat: 1.006 (0.997-1.016) for urban, 1.002 (0.988-1.017) for rural areas; relative effect for cold: 1.023 (1.017-1.030) for urban, 1.012 (1.001-1.023) for rural areas). Findings are suggestive of higher relative cold risks in counties with the less social association, higher population density, less green-space, higher PM_2.5, lower education level, higher residential segregation, higher income inequality, and higher income (e.g., Ratio of Relative Risks 1.72 (0.68, 4.35) comparing low to high education).

CONCLUSION

Results indicate cold-mortality risks in NC, with potential differences by regional, urban-rural areas, and community characteristics.

Temperature changes between neighboring days and childhood asthma: a seasonal analysis in Shanghai, China

Few evidences are available about the impact of temperature variation on childhood asthma in different seasons. This study aimed to assess the influence of temperature changes between neighboring days (TCN) on the exacerbation of asthma among children. Daily outpatient visits for childhood asthma (DOVCA) were collected from 17 main hospitals in Shanghai, China, from 2016 to 2018. A quasi-Poisson regression combined with distributed lagged nonlinear models was employed to estimate the association between TCN and asthma visits in cool or warm seasons, after controlling for short- and long-term trends, day of week, holidays, daily mean temperature, daily mean relative humidity, and air pollutants. The TCN varied from - 9.6 to 6.7 °C. The relationship between TCN and DOVCA greatly varied by season. In warm seasons, positive TCN (temperature rise) was associated with higher risks of asthma outpatient visits and negative TCN (temperature drop) was associated with lower risks; the associations were present on lag 1 day and lasted for 2 weeks; the cumulative relative risk of childhood asthma over 0 to 14 days was 1.98 (95% confidence interval: 1.42, 2.76) and 0.31 (95% confidence intervals: 0.21, 0.44) comparing a TCN of 2.5 °C (5th percentile) and - 3.2 °C (95th percentile) with 0 °C, respectively. In cool seasons, neither negative nor positive TCN showed significant risks. In conclusion, temperature rise might increase the risk of childhood asthma exacerbation and temperature drop might decrease the risks in warm seasons. There were no statistically significant influences in cool seasons.

A Case-Crossover Analysis of Indoor Heat Exposure on Mortality and Hospitalizations among the Elderly in Houston, Texas

BACKGROUND

Despite the substantial role indoor exposure has played in heat wave-related mortality, few epidemiological studies have examined the health effects of exposure to indoor heat. As a result, knowledge gaps regarding indoor heat-health thresholds, vulnerability, and adaptive capacity persist.

OBJECTIVE

We evaluated the role of indoor heat exposure on mortality and morbidity among the elderly (≥65 years of age) in Houston, Texas.

METHODS

Mortality and emergency hospital admission data were obtained through the Texas Department of State Health Services. Summer indoor heat exposure was modeled at the U.S. Census block group (CBG) level using building energy models, outdoor weather data, and building characteristic data. Indoor heat-health associations were examined using time-stratified case-crossover models, controlling for temporal trends and meteorology, and matching on CBG of residence, year, month, and weekday of the adverse health event. Separate models were fitted for three indoor exposure metrics, for individual lag days 0-6, and for 3-d moving averages (lag 0-2). Effect measure modification was explored via stratification on individual- and area-level vulnerability factors.

RESULTS

We estimated positive associations between short-term changes in indoor heat exposure and cause-specific mortality and morbidity [e.g., circulatory deaths, odds ratio per 5°C increase=1.16 (95% CI: 1.03, 1.30)]. Associations were generally positive for earlier lag periods and weaker across later lag periods. Stratified analyses suggest stronger associations between indoor heat and emergency hospital admissions among African Americans compared with Whites.

DISCUSSION

Findings suggest excess mortality among certain elderly populations in Houston who are likely exposed to high indoor heat. We developed a novel methodology to estimate indoor heat exposure that can be adapted to other U.S.

LOCATIONS

In locations with high air conditioning prevalence, simplified modeling approaches may adequately account for indoor heat exposure in vulnerable neighborhoods. Accounting for indoor heat exposure may improve the estimation of the total impact of heat on health. https://doi.org/10.1289/EHP6340.

Air pollution epidemiology: A simplified Generalized Linear Model approach optimized by bio-inspired metaheuristics

Studies in air pollution epidemiology are of paramount importance in diagnosing and improve life quality. To explore new methods or modify existing ones is critical to obtain better results. Most air pollution epidemiology studies use the Generalized Linear Model, especially the default version of R, Splus, SAS, and Stata softwares, which use maximum likelihood estimators in parameter optimization. Also, a smooth time function (usually spline) is generally used as a pre-processing step to consider seasonal and long-term tendencies. This investigation introduces a new approach to GLM, proposing the estimation of the free coefficients through bio-inspired metaheuristics - Particle Swarm Optimization (PSO), Genetic Algorithms, and Differential Evolution, as well as the replacement of the spline function by a simple normalization procedure. The considered case studies comprise three important cities of São Paulo state, Brazil with distinct characteristics: São Paulo, Campinas, and Cubatão. We considered the impact of particles with an aerodynamic diameter less than 10 μm (PM₁₀), ambient temperature, and relative humidity in the number of hospital admissions for respiratory diseases (ICD-10, J00 to J99). The results showed that the new approach (especially PSO) brings performance gains compared to the default version of statistical software like R.

Extreme heat and paediatric emergency department visits in Southwestern Ontario

Objective

The risk of adverse health events is expected to increase with hotter temperatures, particularly among the most vulnerable groups such as elderly persons and children. The objective of this study was to assess the association between extreme heat and daily emergency department visits among children (0 to 17 years) in Southwestern Ontario.

Methods

We examined the average maximum temperature, relative humidity, and daily paediatric emergency department visits in June through August of 2002 to 2019. We reviewed emergency department visits from two academic hospitals. Daily meteorological data from the local weather station were obtained from Environment and Climate Change Canada.

Results

Extreme heat, defined as the 99th percentile of the maximum temperature distribution, occurred at 33.1°C and was associated with an overall 22% increase in emergency department visits, compared to the reference temperature of 21°C. This association was mostly found between the second and fifth day after the exposure, suggesting a slightly delayed effect. The results of the sub-group analysis indicate that the risk of an emergency department visit due to infectious disease increases by 35% and the most pronounced association was noted in children aged 1 to 12 years.

Conclusions

Extreme heat is associated with an increased incidence of emergency department visits in children. As temperatures continue to increase, strategies to mitigate heat-related health risks among children should be developed.

Residential green space and medication sales for childhood asthma: A longitudinal ecological study in Belgium

BACKGROUND

Living in green environments has been associated with various health benefits, but the evidence for positive effects on respiratory health in children is ambiguous.

OBJECTIVE

To investigate if residential exposure to different types of green space is associated with childhood asthma prevalence in Belgium.

METHODS

Asthma prevalence was estimated from sales data of reimbursed medication for obstructive airway disease (OAD) prescribed to children between 2010 and 2014, aggregated at census tract level (n = 1872) by sex and age group (6-12 and 13-18 years). Generalized log-linear mixed effects models with repeated measures were used to estimate effects of relative covers of forest, grassland and garden in the census tract of the residence on OAD medication sales. Models were adjusted for air pollution (PM₁₀), housing quality and administrative region.

RESULTS

Consistent associations between OAD medication sales and relative covers of grassland and garden were observed (unadjusted parameter estimates per IQR increase of relative cover, range across four strata: grassland, β = 0.15-0.17; garden, β = 0.13-0.17). The associations remained significant after adjusting for housing quality and chronic air pollution (adjusted parameter estimates per IQR increase of relative cover, range across four strata: grassland, β = 0.10-0.14; garden, β = 0.07-0.09). There was no association between OAD medication sales and forest cover.

CONCLUSIONS

Based on aggregated data, we found that living in close proximity to areas with high grass cover (grasslands, but also residential gardens) may negatively impact child respiratory health. Potential allergic and non-allergic mechanisms that underlie this association include elevated exposure to grass pollen and fungi and reduced exposure to environmental biodiversity. Reducing the dominance of grass in public and private green space might be beneficial to reduce the childhood asthma burden and may simultaneously improve the ecological value of urban green space.

Climate Change and Childhood Respiratory Health: A Call to Action for Paediatricians

Climate change (CC) is one of the main contributors to health emergencies worldwide. CC appears to be closely interrelated with air pollution, as some pollutants like carbon dioxide (CO2), nitrogen oxides (NOx) and black carbon are naturally occurring greenhouse gases. Air pollution may enhance the allergenicity of some plants and, also, has an adverse effect on respiratory health. Children are a uniquely vulnerable group that suffers disproportionately from CC burden. The increasing global warming related to CC has a big impact on plants' lifecycles, with earlier and longer pollen seasons, as well as higher pollen production, putting children affected by asthma and allergic rhinitis at risk for exacerbations. Extreme weather events may play a role too, not only in the exacerbations of allergic respiratory diseases but, also, in favouring respiratory infections. Even though paediatricians are already seeing the impacts of CC on their patients, their knowledge about CC-related health outcomes with specific regards to children's respiratory health is incomplete. This advocates for paediatricians' increased awareness and a better understanding of the CC impact on children's respiratory health. Having a special responsibility for children, paediatricians should actively be involved in policies aimed to protect the next generation from CC-related adverse health effects. Hence, there is an urgent need for them to take action and successfully educate families about CC issues. This paper aims at reviewing the evidence of CC-related environmental factors such as temperature, humidity, rainfall and extreme events on respiratory allergic diseases and respiratory infections in children and proposing specific actionable items for paediatricians to deal with CC-related health issues in their clinical practice.

Effects of variations in meteorological factors on daily hospital visits for asthma: A time-series study

Few studies have explored the relationships between meteorological factors and asthma. This study explored the associations between daily variations in meteorological factors and hospital visits for asthma among different ages, genders, and asthma subtypes in Shenyang, China. A distributed lag non-linear model with Poisson regression was used; confounding factors included day of the week, holidays, and seasonal patterns, and long-term trends and air pollutants were adjusted using natural cubic splines. The meteorological factor with the largest cumulative effect was barometric pressure, which increased the risk of hospital visits for adult asthma (relative risk [RR] = 2.414), followed by maximum wind speed, which increased hospital visits for asthma for children aged 0-5 years old (RR = 1.47), and pressure, which increased hospital visits for bronchial asthma (RR = 1.298). Meteorological factors showed stronger associations with asthma than air pollutants. Further research should focus more on the effects of meteorological factors on asthma.

Impacts of exposure to humidex on the risk of childhood asthma hospitalizations in Hefei, China: Effect modification by gender and age

BACKGROUND

With global climate change, there is growing concern about the effects of temperature changes on childhood asthma. However, current research only focuses on the effects of temperature, while ignoring the adverse effects of humidity on children.

OBJECTIVES

Our study aimed to quantify the impact of humidex on childhood asthma hospitalizations, which combined temperature and humidity, and further to assess how the effect is modified by individual-factors, such as age and gender.

METHODS

Poisson generalized linear models combined with distributed lag nonlinear models were used to estimate the association between daily childhood asthma hospitalizations and humidex from 2013 to 2016. Air pollutions (CO, O_3, and NO₂) and wind velocity were modelled simultaneously using DLNM, as well as day of week, seasonality and long-term trend.

RESULTS

Low humidex was associated with an increased risk of admissions for asthma in children. The adverse effect appeared on the 4th day, with the RR of 1.045 (95%CI: 1.007-1.084) and lasted until the 7th day (RR: 1.045, 95%CI: 1.006-1.085). Compared with the male, there was an immediate effect on female exposed to low humidex. And the female seems to be more sensitive to low humidex. Besides, the significant effects of humidex on children asthma were detected in the children with preschool and school-age, whereas not for the subgroup of infants. And the school-age children are most sensitive to low humidex.

CONCLUSIONS

Low humidex was associated with the increased risk of admissions for childhood asthma in Hefei. Children suffering from asthma should avoid exposure to the low humidex environment, especially in female and school-age children. In addition, the index of humidex was more significant for disease prevention and public health than the average temperature. These findings may provide epidemiology evidence for formulating precaution guidelines to reduce the risk of childhood asthma hospitalizations.

[Meteorological variables and air pollution and their association with hospitalizations due to respiratory diseases in children: a case study in São Paulo, Brazil]

Urban climate changes, excessive air pollution, and increasing social inequalities have become determinant factors in the high risk of hospitalizations due to respiratory diseases. The current study thus aimed to understand how meteorological factors (air temperature, relative humidity, and precipitation) and air pollution (particulate matter with aerodynamic diameter less than 10µm - PM10) are related to hospitalizations due to respiratory diseases in children in 14 districts in the city of São Paulo, Brazil. The combination of generalized linear models with a negative binomial distribution and distributed lag non-linear model (DLNM) were used as the statistical method to analyze the relationship between hospitalizations, climatic factors, and pollution from 2003 to 2013. The results show statistically significant association with high relative risk between mean air temperature (17.5ºC to 21ºC, for the total analyzed), relative humidity (84% to 98% for females), precipitation (0mm to 2.3mm for the total and both sexes and > 120mm for females), and PM10 (> 35µg/m³ for the total and for females). These results showed that environmental factors contribute to the high risk of hospitalizations.

Impact of the Global Budget Payment System on Expenditure of Cardiovascular Diseases: An Interrupted Time Series Analysis in Shanghai, China

Since few studies evaluated the impact of the global budget payment system (GBPS) over time, and by expenditure type, this paper aims to evaluate the impact of the GBPS on expenditure of inpatients, and explores how hospitals curb the expenditure in patients with cardiovascular diseases (CVDs) in Shanghai. We built a time series model with the monthly expenditure of CVDs from 2009 to 2012. We evaluated the instant impact and trends impact of the GBPS and analyzed results based on medical expenditure types (e.g., drug, examination, cure, unclassified items), discharge number, and expenditure per capita. We found GBPS instantly dropped the medical expenditure by Chinese Yuan (CNY) 55.71 million (p < 0.001), and decreased the monthly increasing trend by CNY 4.23 million (p = 0.011). The discharge number had 10.4% instant reduction and 225.55 monthly decrease (p = 0.021) while the expenditure per capita experienced fewer changes. Moreover, the expenditure of drug and cure had an instant reduction of CNY 28.31 million and 16.28 million (p < 0.001). In conclusion, we considered the GBPS is an effective solution to control the expenditure of CVDs by decreasing the discharge number, and a focus on the drug and cure expenditures lead to greater spend reduction than other types of expenditures.

Urban heat and air pollution: A framework for integrating population vulnerability and indoor exposure in health risk analyses

Urban growth and climate change will exacerbate extreme heat events and air pollution, posing considerable health challenges to urban populations. Although epidemiological studies have shown associations between health outcomes and exposures to ambient air pollution and extreme heat, the degree to which indoor exposures and social and behavioral factors may confound or modify these observed effects remains underexplored. To address this knowledge gap, we explore the linkages between vulnerability science and epidemiological conceptualizations of risk to propose a conceptual and analytical framework for characterizing current and future health risks to air pollution and extreme heat, indoors and outdoors. Our framework offers guidance for research on climatic variability, population vulnerability, the built environment, and health effects by illustrating how health data, spatially resolved ambient data, estimates of indoor conditions, and household-level vulnerability data can be integrated into an epidemiological model. We also describe an approach for characterizing population adaptive capacity and indoor exposure for use in population-based epidemiological models. Our framework and methods represent novel resources for the evaluation of health risks from extreme heat and air pollution, both indoors and outdoors.

[Climate-sensitive diseases in Brazil and the world: systematic reviewEnfermedades sensibles al clima en Brasil y el mundo: revisión sistemática]

OBJECTIVE

To survey the literature regarding climate-sensitive diseases (CSD) and the impacts of climate changes on health.

METHOD

This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The Lilacs, SciELO, Scopus, and PubMed databases were searched in July 2017 without temporal restrictions for articles published in in Portuguese, English and Spanish. The following search strategy was used in all databases: (climate) AND (disease) AND (sensitive).

RESULTS

The systematic review included 106 articles, most of which focused on dengue, malaria, and respiratory and cardiovascular diseases. The most commonly studied climate variables were temperature and precipitation. The studies revealed a relationship between the incidence of certain diseases, especially cardiovascular and respiratory diseases, dengue, malaria, and arboviral diseases, and climate conditions in different regions of the world. This relationship was analyzed considering both past data on the incidence of diseases and climate variables and projections regarding the future incidence of diseases according to expected climate variations. A greater number of studies was performed by authors originating from developed countries. The world regions most often studied were China, the United States, Australia, and Brazil.

CONCLUSIONS

Despite the increase in the number of published articles on this theme, a greater number of climate and environmental variables must be studied, with expansion of studies to additional regions in the world.

Urban expansion simulation and the spatio-temporal changes of ecosystem services, a case study in Atlanta Metropolitan area, USA

Urban expansion can lead to land use changes and, hence, threatens the ecosystems. Understanding the effects of urbanization on ecosystem services (ESs) can provide scientific guidance for land use planning and the protection of ESs. We established a framework to assess the spatial distributions of ESs based on land use changes in the Atlanta Metropolitan area (AMA) from 1985 to 2012. A new comprehensive ecosystem service (CES) index was developed to reflect the comprehensive level of ESs. Associated with the influential factors, we simulated the business as usual scenario in 2030. Four alternative scenarios, including more compact growth (MCG), riparian vegetation buffer (RVB), soil conservation (SC), and combined development (CD) scenarios were developed to explore the optimal land use strategies which can enhance the ESs. The results showed that forest and wetland had the greatest decreases, while low and high intensity built-up lands had the greatest increases. The values of CES and most of ESs decreased significantly due to the sprawling expansion of built-up land. The scenario analysis revealed that the CD scenario performs best in CES value, while it performs the worst in food supply. Compared with the RVB and SC scenarios, MCG scenario is a more optimal land use strategy to enhance the ESs without at the expense of food supply. To integrate multiple ESs into land use planning and decision making, corresponding land management policies and ecological engineering measures should be implemented to enhance: (1) the water yield and water purification in urban core counties, (2) the carbon storage, habitat quality, and recreational opportunity in counties around the core area, and (3) the soil conservation and food supply in surrounding suburban counties. The land use strategies and ecological engineering measures in this study can provide references for enhancing the ESs in the AMA and other metropolitan areas.

Associations between Ambient Fine Particulate Oxidative Potential and Cardiorespiratory Emergency Department Visits

BACKGROUND

Oxidative potential (OP) has been proposed as a measure of toxicity of ambient particulate matter (PM).

OBJECTIVES

Our goal was to address an important research gap by using daily OP measurements to conduct population-level analysis of the health effects of measured ambient OP.

METHODS

A semi-automated dithiothreitol (DTT) analytical system was used to measure daily average OP (OP^DTT) in water-soluble fine PM at a central monitor site in Atlanta, Georgia, over eight sampling periods (a total of 196 d) during June 2012-April 2013. Data on emergency department (ED) visits for selected cardiorespiratory outcomes were obtained for the five-county Atlanta metropolitan area. Poisson log-linear regression models controlling for temporal confounders were used to conduct time-series analyses of the relationship between daily counts of ED visits and either the 3-d moving average (lag 0-2) of OP^DTT or same-day OP^DTT. Bipollutant regression models were run to estimate the health associations of OP^DTT while controlling for other pollutants.

RESULTS

OP^DTT was measured for 196 d (mean=0.32 nmol/min/m³, interquartile range=0.21). Lag 0-2 OP^DTT was associated with ED visits for respiratory disease (RR=1.03, 95% confidence interval (CI): 1.00, 1.05 per interquartile range increase in OP^DTT), asthma (RR=1.12, 95% CI: 1.03, 1.22), and ischemic heart disease (RR=1.19, 95% CI: 1.03, 1.38). Same-day OP^DTT was not associated with ED visits for any outcome. Lag 0-2 OP^DTT remained a significant predictor of asthma and ischemic heart disease in most bipollutant models.

CONCLUSIONS

Lag 0-2 OP^DTT was associated with ED visits for multiple cardiorespiratory outcomes, providing support for the utility of OP^DTT as a measure of fine particle toxicity. https://doi.org/10.1289/EHP1545.