Air pollutants and asthma patient visits: Indication of source influence

Causal relationship between outdoor atmospheric quality and pediatric asthma visits in hangzhou

Many air pollutants and climate variables have proven to be significantly associated with pediatric asthma and have worsened asthma symptoms. However, their exact causal effects remain unclear. We explored the causality between air pollutants, climate, and daily pediatric asthma patient visits with a short-term lag effect. Based on eight years of daily environmental data and daily pediatric asthma patient visits, Spearman correlation analysis was used to select the air pollutants and climate variables that correlated with daily pediatric asthma patient visits at any time (with a lag of 1-6 days). We regarded these environmental variables as treatments and built multiple- and single-treatment causal inference models using the Dowhy library (a Python library for causal inference by graphing the model, quantitatively evaluating causal effects, and validating the causal assumptions) to estimate the quantitative causal effect between these correlated variables and daily pediatric asthma patient visits in lag time. The multiple-treatment causal inference model was a model with 8 treatments (Visibility, Precipitation, PM₁₀, PM_2.5, SO₂, NO₂, AQI and CO), 1 outcome (daily pediatric asthma patients visits), and 5 confounders (Humidity, Temperature, Sea level pressure, wind speed and unobserved confounders "U"). Single-treatment causal inference models were 8 models, and each model has 1 treatment, 1 outcome and 12 confounders. Spearman correlation analysis showed that precipitation, wind speed, visibility, air quality index, PM_2.5, PM₁₀, SO₂, NO₂, and CO were significantly associated variables at all times (p < 0.05). The multiple-treatment model showed that pooled treatments had significant causality for the short-term lag (lag1-lag6; p < 0.05). Causality was mainly due to SO₂. In the single-treatment models, visibility, SO₂, NO₂, and CO exhibited significant causal effects at any one time (p < 0.05). SO₂ and CO exhibited stronger positive causal effects. The causal effect of SO₂ reached its maxima (causal effect = 11.41, p < 0.05) at lag5. The greatest causal effect of CO appeared at lag3 (causal effect = 10.67, p < 0.05). During the eight year-period, the improvements in SO₂, CO, and NO₂ in Hangzhou were estimated to reduce asthma visits by 8478.03, 3131.08, and 1341.39 per year, respectively. SO₂, NO₂, CO, and visibility exhibited causal effects on daily pediatric asthma patient visits; SO₂ was the most crucial causative variable with a relatively higher causal effect, followed by CO. Improvements in atmospheric quality in the Hangzhou area have effectively reduced the incidence of asthma.

Characteristics, health risks, and premature mortality attributable to ambient air pollutants in four functional areas in Jining, China

Air pollution is one of the leading causes for global deaths and understanding pollutant emission sources is key to successful mitigation policies. Air quality data in the urban, suburban, industrial, and rural areas (UA, SA, IA, and RA) of Jining, Shandong Province in China, were collected to compare the characteristics and associated health risks. The average concentrations of PM_2.5, PM₁₀, SO₂, NO₂, and CO show differences of -3.87, -16.67, -19.24, -15.74, and -8.37% between 2017 and 2018. On the contrary, O₃ concentrations increased by 4.50%. The four functional areas exhibited the same seasonal variations and diurnal patterns in air pollutants, with the highest exposure excess risks (ERs) resulting from O₃. More frequent ER days occurred within the 25-30°C, but much larger ERs are found within the 0-5°C temperature range, attributed to higher O₃ pollution in summer and more severe PM pollution in winter. The premature deaths attributable to six air pollutants can be calculated in 2017 and 2018, respectively. Investigations on the potential source show that the ER of O₃ (r of 0.86) had the tightest association with the total ER. The bivariate polar plots indicated that the highest health-based air quality index (HAQI) in IA influences the HAQI in UA and SA by pollution transport, and thus can be regarded as the major pollutant emission source in Jining. The above results indicate that urgent measures should be taken to reduce O₃ pollution taking into account the characteristics of the prevalent ozone formation regime, especially in IA in Jining.

Role of ambient air pollution in asthma spread among various population groups of Lahore City: a case study

Air pollution levels rise as a result of industrial and vehicular emissions, epidemiological issues such as asthma become more prevalent in Lahore, Punjab, Pakistan and cause adverse public health effects. Many studies explored the association between air pollutants and frequency of asthma hospital visits, although their effects are unclear. This study examined the link between air pollution, asthma, and socioeconomic and demographic factors. A questionnaire survey was administered among four age groups (15-25, 25-45, 45-60, and over 60 years old) in public and private hospitals of Lahore city. Daily average concentrations of five air pollutants including carbon monoxide (CO), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone (O₃), and particulate matter (PM_2.5 and PM₁₀) were recorded at ten fixed air monitoring sites in Lahore city. There were favorable connections between outpatient department (OPD) asthma visits (64%) and levels of outdoor air quality during winter season throughout the study period. The correlation between 1, 29, and 370 asthma patients and average daily air pollution levels found that the condition was more prevalent in females (53%) than males (47%). There was a significant correlation between PM₁₀ exposure and asthma OPD visits in the city (p 0.001), as well as the elevated PM₁₀ levels were substantially linked with OPD asthma visits over the winter season in the city. The hazard index (HI) for all adult population was estimated 0.001132. The study's findings indicate that exposure to ambient air pollution is a significant predictor of asthma hospital visits, particularly among the elderly. Strategies can be developed by policymakers in response to the worrying situation of allergic disease asthma in industrial cities due to air pollution.

Characteristics of industrial hazardous waste generation in South Korea from 2008 to 2018 based on decoupling and decomposition analysis

The industrial hazardous waste (IHW) generation to meet consumption is steadily increasing, resulting in environmental, health, and social problems around the world. To address IHW at the source, it is critical to understand the generation characteristics and key drivers on industrial hazardous waste generation (IHWG). This study analysed the generation characteristics of IHW of South Korea from 2008 to 2018 by decoupling and index decomposition analysis using Log Mean Divisia Index (LMDI) model. South Korea presented unstable decoupling of IHWG from economic growth, so more effective waste management regulations are needed to support a stable decoupling. One most critical finding was that the factors of industrial output and industrial characteristic of IHWG-to-energy were major driving factors influencing the increase of IHWG, whereas those of industrial structure and energy efficiency affect to the decrease of IHWG in most industries. In addition, the result clearly confirmed that the contribution of driving factors affecting the IHWG differs by industry. These results provide significant policy insights that the South Korean government needs institutional improvement and refinement of customised IHW management according to the characteristics of IHWG.

A Mobile App for Children With Asthma to Monitor Indoor Air Quality (AirBuddy): Development and Usability Study

Background

Indoor air quality is an important environmental factor that triggers and exacerbates asthma, the most common chronic disease in children. A mobile app to monitor indoor air quality could help occupants keep their indoor air quality clean. However, no app is available that allows children to monitor and improve their indoor air quality.

Objective

Previously, we conducted a series of user-centered design studies to identify user needs and design requirements toward creating a mobile app that helps children with asthma to engage in monitoring and improving indoor air quality as part of their asthma management. Based on the findings from these studies, we created AirBuddy, a child-friendly app that visualizes air quality indoors and outdoors.

Methods

This paper reports on the findings from a field deployment with 7 pediatric asthma patients, where we evaluated AirBuddy’s usability and usefulness in real-world settings by conducting weekly semistructured interviews for 8 weeks.

Results

All participants positively responded to the usefulness and usability of AirBuddy, which we believe is thanks to the iterative, user-centered design approach that allowed us to identify and address potential usability issues early on and throughout the design process.

Conclusions

This project contributes to the field of mHealth app design for children by demonstrating how a user-centered design process can lead to the development of digital devices that are more acceptable and relevant to target users’ needs.

Designing an Indoor Air Quality Monitoring App for Asthma Management in Children: User-Centered Design Approach

BACKGROUND

Indoor air pollution is a well-known risk factor that triggers and exacerbates asthma, the most common pediatric chronic disease. Using a mobile app to monitor indoor air quality could be promising in engaging children in keeping their indoor air quality clean and healthy as secondary environmental prevention for asthma management. However, no app is available to allow children to monitor, assess, and improve their indoor air quality.

OBJECTIVE

This study aims to design a mobile app that encourages children to monitor indoor air quality and track their asthma conditions through a user-centered, iterative design approach.

METHODS

We reviewed existing apps for indoor air quality monitoring or asthma management for children and conducted two sets of semistructured interviews with 12 children with asthma. We then iteratively created prototypes and evaluated and revised them.

RESULTS

Participants raised a series of outstanding questions on the prototype features and content that described their needs and perspectives, which informed the final designs. Following the identified requirements and recommendations, we developed two versions of the app: AirBuddy for presenting concrete information for indoor air quality and AirPet for gamifying the practice of monitoring indoor air quality.

CONCLUSIONS

By following an iterative, user-centered design process, we developed two versions of an app to encourage children with asthma to monitor indoor air quality and track their asthma condition. The user-centered design approach revealed two crucial aspects that require deeper consideration when creating a child-friendly app, including balancing brevity and expressivity and considering the longitudinal effects of gamification. As a next step, we plan to conduct a longitudinal deployment study to evaluate the real-world effects of our apps.

Effects of Air Pollutants on Airway Diseases

Air pollutants include toxic particles and gases emitted in large quantities from many different combustible materials. They also include particulate matter (PM) and ozone, and biological contaminants, such as viruses and bacteria, which can penetrate the human airway and reach the bloodstream, triggering airway inflammation, dysfunction, and fibrosis. Pollutants that accumulate in the lungs exacerbate symptoms of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Asthma, a heterogeneous disease with complex pathological mechanisms, is characterized by particular symptoms such as shortness of breath, a tight chest, coughing, and wheezing. Patients with COPD often experience exacerbations and worsening of symptoms, which may result in hospitalization and disease progression. PM varies in terms of composition, and can include solid and liquid particles of various sizes. PM concentrations are higher in urban areas. Ozone is one of the most toxic photochemical air pollutants. In general, air pollution decreases quality of life and life expectancy. It exacerbates acute and chronic respiratory symptoms in patients with chronic airway diseases, and increases the morbidity and risk of hospitalization associated with respiratory diseases. However, the mechanisms underlying these effects remain unclear. Therefore, we reviewed the impact of air pollutants on airway diseases such as asthma and COPD, focusing on their underlying mechanisms.

Impact of atmospheric pollution on asthma and bronchitis based on lichen biomonitoring using IAP, IHI and GIS in Algiers Bay (Algeria)

We investigated the association between air pollution and asthma and bronchitis hospital admissions in Algiers city (Algeria). In addition, we used geographic information systems (GIS) and statistical methods to evaluate their correlation with the atmospheric pollution estimated by the lichen biomonitoring method of the index of atmospheric purity (IAP), the index of human impact (IHI) and environmental parameters. Thus, we georeferenced 976 local patients (including 771 patients with asthma and 205 patients with bronchitis). Then, we compared the patients to the spatial distribution of IAP in thirty-five areas (communities). The results revealed a significant difference in the mean spatial variation in the diseases among those areas. In fact, maps and generalized linear models (GLMs) revealed a significant negative correlation between IAP and diseases. Therefore, redundancy analysis (RDA) and Monte Carlo tests described a significant effect of IAP, urbanization and the number of roads on the distribution of diseases. We hope our findings contribute to enriching the literature on health research with a low-cost method of monitoring outdoor air pollution.

Acute Effects of Air Pollution on Hospital Admissions for Asthma, COPD, and Bronchiectasis in Ahvaz, Iran

Background and Aim

Although air pollution is a serious problem in Ahvaz, the association between air pollution and respiratory diseases has not been studied enough in this area. The aim of this study was to determine the relation between short-term exposure to air pollutants and the risk of hospital admissions due to asthma, COPD, and bronchiectasis in Ahvaz.

Methods

Hospital admissions data and air pollutants including O3, NO, NO2, SO2, CO, PM10, and PM2.5 were obtained from 2008 to 2018. Adjusted Quasi-Poisson regression with a distributed lag model, controlled for trend, seasonality, weather, weekdays, and holidays was used for data analysis.

Results

The results showed a significant increase in hospital admissions for asthma (RR=1.004, 95% CI: 1.002-1.007) and COPD (RR=1.003, 95% CI: 1.001-1.005) associated with PM2.5. PM10 was associated with increased hospital admissions due to bronchiectasis in both genders (Men: RR=1.003, 95% CI: 1.001-1.006) (Female: RR=1.003, 95% CI: 1.000-1.006). NO2 was also associated with an increased risk of hospital admissions for asthma (RR=1.040, 95% CI: 1.008-1.074) and COPD (RR=1.049, 95% CI: 1.010-1.090). SO2 was associated with the risk of hospital admissions of asthma (RR=1.069, 95% CI: 1.017-1.124) and bronchiectasis (RR=1.030, 95% CI: 1.005-1.056). Finally, CO was associated with COPD (RR=1.643, 95% CI: 1.233-2.191) and bronchiectasis (RR=1.542, 95% CI: 1.035-2.298) hospital admissions.

Conclusion

Short-term exposure to air pollutants significantly increases the risk of hospital admissions for asthma, COPD, and bronchiectasis in the adult and elderly population.

Study on the association between ambient air pollution and daily cardiovascular death in Hefei, China

Cardiovascular disease has always been the most serious public health problem in China. Although many studies have found that the risk of death caused by cardiovascular disease is related to air pollutants, the existing results are still inconsistent. The aim of this study was to investigate the effects of air pollutants on the risk of daily cardiovascular deaths in Hefei, China. Daily data on cardiovascular deaths, daily air pollutants, and meteorological factors from 2007 to 2016 were collected in this study. A time-series study design using a distributed lag nonlinear model was employed to evaluate the association between air pollutants and cardiovascular deaths. First, a single air pollutant model was established based on the minimum value of Akaike information criterion (AIC), and the single day lag effects and multi-day lag effects were discussed separately. Then, two-pollutant models were fitted. Subgroup analyses were conducted by gender (male and female), age (< 65 age and ≥ 65 age), and disease type (ischemic heart disease and cerebral vascular disease). There were 34,500 cases of cardiovascular deaths during the period 2007-2016, and the average concentrations of air pollutants (PM₁₀, SO₂, NO₂, PM_2.5, CO, O₃) were 106.11, 20.34, 30.49, 72.59, 958.7, and 67.88 μg/m³, respectively. An increase of interquartile range (IQR) in PM₁₀, SO₂, NO₂, PM_2.5, CO, and O₃ were associated with an increase of 4.34% (95%CI 1.54~7.23%) at lag 0-6, 5.79% (95%CI 2.43~9.27%) at lag 0-5, 4.47% (95%CI 1.64~7.37%) at lag 0-5, 3.14% (95%CI 0.03~6.36%) at lag 0-4, 3.11% (95%CI 0.21~6.10%) at lag 0-3, and 8.17% (95%CI 1.89~14.84%) at lag 0-5 in cardiovascular deaths, respectively. Females, older group (≥ 65 years) and deaths from cerebral vascular disease were more vulnerable to air pollution than males, younger individuals (< 65 years) and deaths from ischemic heart disease. Our results suggest that air pollution increased the risk of cardiovascular deaths in Hefei. These findings can provide evidence for effective air quality interventions in Hefei.

The impact of ambient particulate matter on hospital outpatient visits for respiratory and circulatory system disease in an urban Chinese population

There are limited evidence on the association between short-term exposure to ambient particulate matter (PM) and overall hospital outpatient visits for respiratory system disease (RESD) and cardio-cerebrovascular system disease (CCD) in high-polluted countries like China. Though previous epidemiological studies of RESD and CCD generally applied a linear relationship of the acute PM effects, it is unclear whether this linear exposure-response relationship holds in high pollution area. In this study, a time-series study during 2013 through 2016 was conducted to investigate 245,442 and 430,486 hospital visits for RESD and CCD respectively from Nanjing city, China. A combination of logistic generalized additive model (GAM) was used to evaluate the exposure-response associations. The results disclosed that a 10 μg/m³ increase in PM_2.5 and PM₁₀ concentration on the current day of exposure (lag 0) was associated with 0.36% (95% CI: -0.02%-0.73%) and 0.33% (0.07%-0.60%) increase in RESD; and 0.42% (0.00%-0.85%) and 0.37% (0.08%-0.67%) increase in CCD. The exposure-response association was approximately linear within 0-150 μg/m³ of PM concentration and non-linear across the full range of exposures. The effects of PM on RESD and CCD were sensitive to additional adjustment for co-pollutants, indicating the health effects of air pollution mixture in Nanjing city. There was no evidence of potential effect modification of RESD and CCD by season (cold and warm), age (5-64, 65-74, ≧75 years) and sex (male and female) groups. Though not statistically significant, the estimated risks in warm season were higher than those in cold season, suggesting potential synergistic effects of ambient PM pollution and temperature on triggering RESD and CCD.

Longitudinal trends in asthma emergency department visits, pollutant and pollen levels, and weather variables in the Bronx from 2001-2008

Objective: To evaluate how asthma-related emergency department visits (AREDV), air pollutant levels, pollen counts, and weather variables changed from 2001 to 2008 in the Bronx, NY. Methods: 42,065 daily AREDV values (1 January 2001 to 31 December 2008) were collected using our institution's Clinical Looking Glass software. Daily values of sulfur dioxide (SO₂), carbon monoxide (CO), ozone (O₃), nitrogen dioxide (NO₂), temperature, and humidity were obtained from the National Climatic Data Center's Bronx station. Daily tree pollen counts were obtained from the Armonk counting station near the Bronx. Median values for each variable were analyzed using the Mann-Whitney test to compare 2001-2004 and 2005-2008 values. Simple linear regression examined associations between AREDV and individual pollutants. Due to seasonal variations of the variables, each season was considered separately. Results: There were significant decreases for AREDV, SO₂, CO, and humidity for all seasons, and for NO₂ in the spring and winter. Significant increases occurred for O₃ in the spring, fall, and winter; for temperature in the summer and winter; and for tree pollen in the spring. Significant positive associations were found between AREDV and SO₂, CO, NO₂, and humidity, respectively, while significant negative associations were found between AREDV and O₃ and temperature, respectively. Conclusions: From 2001 to 2008, significant: a) decreases in AREDV, SO₂, CO, and humidity for all seasons, and decreases in NO₂ for the spring and winter; and b) increases in O₃, temperature, and spring tree pollen were observed. By tracking and anticipating environmental and pollutant changes, efforts can be made to minimize AREDV.

Indoor air pollution aggravates asthma in Chinese children and induces the changes in serum level of miR-155

Indoor air pollution is associated with childhood asthma but the molecular mechanism remains unclear. We aimed to explore the relationship between indoor air pollution and pediatric asthma, and the potential molecular mechanism. The serum level of miR-155 was measured by real-time qPCR in 180 Chinese children with asthma caused by air pollution (an asthma group). Meanwhile, 180 healthy subjects were selected as a control group. HCHO, NO₂, and particles (PM₁₀, PM_2.5, and PM₁) were measured. Univariate and multivariate logistic regression were analyzed to assess the relationship between air pollutants and asthma risk. A rank correlation test was used to explore the relationship between serum level of miR-155 and the level of PM_2.5 or HCHO. Serum level of miR-155 was higher in the asthma group than the control group (p < 0.001). The history of childhood allergy, breastfeeding, environmental tobacco smoke, PM_2.5, and HCHO were significantly different between two groups (p < 0.05). Serum level of miR-155 was closely associated with the levels of indoor PM_2.5 and HCHO in the asthma group (p < 0.05) but not in the control group (p > 0.05). Indoor air pollution aggravates the asthma in Chinese children and induces the changes in the serum level of miR-155. Abbreviation: DEP: Diesel exhaust particles; PAHs: Polycyclic aromatic hydrocarbons; THBS1: thrombospondin 1; ISAAC: International Study of Asthma and Allergies in Childhood; PFTs: Pulmonary Function Tests; FEV1: The first second of forced expiration; EDTA, ethylenediaminetetraacetic acid; RT-qPCR, Reverse transcription quantitative real-time PCR; ETS: environmental tobacco smoke; PAEs: phthalate esters.

Comparisons of combined oxidant capacity and redox-weighted oxidant capacity in their association with increasing levels of FeNO

BACKGROUND

Some ozone (O₃) and nitrogen dioxides (NO₂) health effects studies use O_x (sum value) as a surrogate. However, little is known about how this related to O_x^wt (weighted value).

OBJECTIVE

We investigated the effects of redox-weighted oxidant capacity (O_x^wt) on fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation, in a set of chronic obstructive pulmonary disease (COPD) patients. We also compare combined oxidant capacity (O_x) and O_x^wt in their associations with increasing levels of FeNO.

METHODS

We measured FeNO values in 600 participants who have COPD at Shanghai Pulmonary Hospital. O_x was calculated directly by the sum of O₃ and NO₂. The redox-weighted oxidant capacity was calculated by denoting O_x^wt as the weighted average of redox potentials. We applied generalized additive models (GAM) to investigate the impacts of O_x and O_x^wt on FeNO levels, respectively. We fitted the same models for the influence of O₃ and NO₂ individually and jointly on FeNO levels to compare the result of O_x and O_x^wt.

RESULTS

O_x^wt were significantly linked with FeNO levels. The impact was robustest in current day after exposure, and were closely linked with the adjustment of PM_2.5. A 10 μg m^-3 increase in average O_x^wt concentrations was linked to 0.88 (95% CI: -1.46, 3.28) increase, whereas a 10 μg m^-3 increase in average O_x concentration was linked to 0.62 (95% CI: -0.79, 2.07) increase in FeNO. In two-pollutant models, an increase of 10 μg m^-3 in average O₃ concentrations with adjustment of NO₂ was associated with 0.57 (95% CI: -1.26, 2.01) increase in FeNO. The impact estimates of O_x and O_x^wt were statistically significant among males, non-smoking and elders who age above 65 years old.

CONCLUSIONS

This analysis demonstrated that O_x^wt is used as a better indicator of atmospheric oxidative capacity as a proxy of O₃ and NO₂ in further epidemiological studies.