Air Pollution, Disease Burden, and Health Economic Loss in China

Costs of Air Pollution in California's San Joaquin Valley: A Societal Perspective of the Burden of Asthma on Emergency Departments and Inpatient Care

Introduction

The San Joaquin Valley (SJV) is often recognized as one of the most polluted regions in the US. Periods of pollution exposure are associated with increased health burden related to respiratory inflammation and undermined lung function, which aggravates respiratory diseases such as asthma and leads to symptoms such as coughing, wheezing, or difficulty breathing. Asthma costs US$ 82 billion annually in healthcare costs, missed work and school in the US.

Methods

Employing a societal perspective, a cost of illness design was combined with environmental epidemiological methods to analyze the economic impact of O3, NO2, and PM2.5-related adverse respiratory health outcomes amongst SJV residents who attended the emergency department (ED) or were hospitalized in 2016.

Results

Asthma exacerbations monetized value ranged from US$ 3353 to US$ 5003 per ED visit and for hospital admissions US$ 2584 per inpatient day for adults 65 years and older to US$ 3023 per child. The estimated value to society in healthcare costs, productivity losses, school absences, and opportunity costs from air pollution adverse health outcomes totaled US$ 498,014,124 in ED visits and US$ 223,552,720 in hospital admissions for the SJV population in 2016. The marginal reduction in the background concentrations of pollutants would avert 21,786 ED adverse events and 19,328 hospitalizations from the health burden on the SJV population or US$ 8,024,505 cost savings due to O3, US$ 82,482,683 from NO2 reductions, and US$ 46,214,702 from decreased concentration of PM2.5.

Conclusion

This study provides evidence that air pollution is a negative externality that imposes substantial social, environmental, and healthcare costs on the SJV. Furthermore, the region would avert significant adverse health outcomes realizing economic savings by reducing air pollution and exposures.

Public perceptions of air pollution and its impacts on fertility desire: a nationwide study in China

Over the past few years, there has been a significant focus on air pollution due to its various detrimental effects on human health. However, its influence on people's tendency to have children remains uncertain, as only a few studies have examined the correlation between public perception of air pollution and the desire to start a family. This article introduces a theoretical framework utilizing a two-stage interval iteration model to explore the connection between children's relative utility and the perception of air pollution. Data for this study were gathered from the "Chinese General Social Survey" (CGSS 2013). The CGSS 2013 project employed a four-stage stratified random sampling technique and conducted household interviews using questionnaires. The sample covered 28 provincial-level cities across China. The hypothesis was tested using a Probit regression model. The findings indicate that individuals considering air pollution a significant issue are 8.62% less likely to have more than one child. The variation in fertility desire sensitivity to air pollution points to heterogeneity among residents, such as registered residents and those living in various residential areas, as well as individuals with different characteristics like education levels. The study concludes that air quality significantly influences human fertility desire, highlighting the urgent necessity to raise awareness of environmental protection issues among both the public and authorities. In particular, there are two key steps to address this issue. Firstly, the government should establish clear air pollution control objectives and refine policies to enhance governance efficiency. Secondly, there is a need to encourage environmentally friendly behaviours among the public, promote more significant involvement in public environmental matters, and ensure effective oversight of the government's responsibilities in managing air pollution.

Abrupt exacerbation in air quality over Europe after the outbreak of Russia-Ukraine war

Much attention has been paid to the world economy and social situations in response to the outbreak of war between Russia and Ukraine in the context of COVID-19. However, much less attention has been paid to the detrimental effect of war on the atmospheric environment. Here, we used an extended deweathered-detrended technique to quantitatively evaluate changes in ambient NO2, O3, and PM2.5 AQI levels arising from emission changes (due to pandemic-driven lockdowns and war-related activities) in European cities. Results show pandemic-induced lockdowns mitigated regional air pollution in Europe, but the war activities led to an average increase of approximately 9.78% in PM2.5 and 10.07% in NO2, along with an average decrease of about 7.93% in O3 levels in cities near the war zones. Moreover, the regional air pollution exacerbated by the war activities has offset the improvements in air quality observed during the COVID-19 pandemic. The potential mechanism analysis show that the increase in atmospheric pollutant emissions driven by the war activities led to the complexity of chemical reactions in the mixed atmospheric system, which posed a huge challenge to the alleviation of air pollution in the region. This study highlights the urgent need for a ceasefire from an environmental perspective.

Identifying the causal effects of long-term exposure to PM2.5 and ground surface ozone on individual medical costs in China-evidence from a representative longitudinal nationwide cohort

BACKGROUND

There is little evidence on whether PM_2.5 and ground surface ozone have consistent effects on increased individual medical costs, and there is a lack of evidence on causality in developing countries.

METHODS

This study utilized balanced panel data from 2014, 2016, and 2018 waves of the Chinese Family Panel Study. The Tobit model was developed within a counterfactual causal inference framework, combined with a correlated random effects and control function approach (Tobit-CRE-CF), to explore the causal relationship between long-term exposure to air pollution and medical costs. We also explored whether different air pollutants exhibit comparable effects.

RESULTS

This study encompassed 8928 participants and assessed various benchmark models, highlighting the potential biases from failing to account for air pollution endogeneity or overlooking respondents without medical costs. Using the Tobit-CRE-CF model, significant effects of air pollutants on increased individual medical costs were identified. Specifically, margin effects for PM_2.5 and ground-level ozone signifying that a unit increase in PM_2.5 and ground-level ozone results in increased total medical costs of 199.144 and 75.145 RMB for individuals who incurred fees in the previous year, respectively.

CONCLUSIONS

The results imply that long-term exposure to air pollutants contributes to increased medical costs for individuals, offering valuable insights for policymakers aiming to mitigate air pollution's consequences.

A nomogram for predicting the 4-year risk of chronic kidney disease among Chinese elderly adults

BACKGROUND

Chronic kidney disease (CKD) has become a major public health problem across the globe, leading to various complications. This study aimed to construct a nomogram to predict the 4-year risk of CKD among Chinese adults.

METHODS

The study was based on the China Health and Retirement Longitudinal Study (CHARLS). A total of 3562 participants with complete information in CHARLS2011 and CHARLS2015 were included, and further divided into the training cohort and the validation cohort by a ratio of 7:3. Univariate and multivariate logistic regression analyses were used to select variables of the nomogram. The nomogram was evaluated by receiver-operating characteristic curve, calibration plots, and decision curve analysis (DCA).

RESULTS

In all, 2494 and 1068 participants were included in the training cohort and the validation cohort, respectively. A total of 413 participants developed CKD in the following 4 years. Five variables selected by multivariate logistic regression were incorporated in the nomogram, consisting of gender, hypertension, the estimated glomerular filtration rate (eGFR), hemoglobin, and Cystatin C. The area under curve was 0.809 and 0.837 in the training cohort and the validation cohort, respectively. The calibration plots showed agreement between the nomogram-predicted probability and the observed probability. DCA indicated that the nomogram had potential clinical use.

CONCLUSIONS

A predictive nomogram was established and internally validated in aid of identifying individuals at increased risk of CKD.

Short-term effects of ambient particulate matter (PM1, PM2.5 and PM10) on influenza-like illness in Guangzhou, China

BACKGROUND

Particulate matter (PM) has been linked to respiratory infections in a growing body of evidence. Studies on the relationship between ILI (influenza-like illness) and PM₁ (particulate matter with aerodynamic diameter ≤1 μm) are, however, scarce. The purpose of this study was to investigate the effects of PM on ILI in Guangzhou, China.

METHODS

Daily ILI cases, air pollution records (PM₁, PM_2.5, PM₁₀ and gaseous pollutants), and metrological data between 2014 and 2019 were gathered from Guangzhou, China. To estimate the risk of ILI linked with exposure to PM pollutants, a quasi-Poisson regression was used. Additionally, subgroup analyses stratified by gender, age and season were carried out.

RESULTS

For each 10 μg/m³ increase of PM₁ and PM_2.5 over the past two days (lag01), and PM₁₀ over the past three days (lag02), the relative risks (RR) of ILI were 1.079 (95% confidence interval [CI]: 1.050, 1.109), 1.044 (95% CI: 1.027, 1.062) and 1.046 (95% CI: 1.032, 1.059), respectively. The estimated risks for men and women were substantially similar. The effects of PM pollutants between male and female were basically equivalent. People aged 15-24 years old were more susceptive to PM pollutants.

CONCLUSIONS

It implies that PM₁, PM_2.5 and PM₁₀ are all risk factors for ILI, the health impacts of PM pollutants vary by particle size. Reducing the concentration of PM₁ needs to be considered when generating a strategy to prevent ILI.

Analysis of air pollution in Fenwei Plain in China based on functional spatial autoregressive combined model

The Fenwei Plain is listed as one of the most serious air pollution regions in China, along with Beijing-Tianjin-Hebei and Yangtze River Delta regions. This paper proposed a functional data analysis method to study the environmental pollution problem in the Fenwei Plain of China. Functional spatial autoregressive combined (FSAC) model with spatial autocorrelation of both the response variable and error term is developed. The model takes the SO2 concentration of Fenwei Plain as the dependent variable and the dew point temperature as the independent variable and realizes the maximum likelihood estimation using functional principal component analysis to obtain the asymptotic properties of parameter estimation and the confidence interval of the slope function. According to the findings of the empirical analysis of the Fenwei Plain, the SO2 concentration has significant seasonal characteristics and has decreased year over year for three years in a row. Winter is the season with the highest concentration on the Fenwei Plain, followed by spring and autumn, while summer is the season with the lowest concentration. Winter also has a high spatial autocorrelation. The FSAC model is more effective at fitting the concentration and dew point temperature of the Fenwei Plain in China because its mean square error (MSE) is significantly lower than that of the other models. As a result, this paper can more thoroughly study the pollution problem on the Fenwei Plain and offer guidance for prevention and control.

Effects of Ambient Particulate Matter (PM2.5) Exposure on Calorie Intake and Appetite of Outdoor Workers

Malaysia has been experiencing smoke-haze episodes almost annually for the past few decades. PM2.5 is the main component in haze and causes harmful impacts on health due to its small aerodynamic size. This study aimed to explore the implications of PM2.5 exposure on the dietary intake of working individuals. Two phased 13-weeks follow-up study was conducted involving 440 participants, consisting of two cohorts of outdoor and indoor workers. Ambient PM2.5 concentrations were monitored using DustTrakTM DRX Aerosol Monitor. Data on Simplified Nutritional Appetite Questionnaire (SNAQ) and 24 h diet recall were collected weekly. The highest PM2.5 concentration of 122.90 ± 2.07 µg/m3 was recorded in August, and it vastly exceeded the standard value stipulated by US EPA and WHO. SNAQ scores and calorie intake were found to be significantly (p < 0.05) associated with changes in PM2.5 exposure of outdoor workers. Several moderate and positive correlations (R-value ranged from 0.4 to 0.6) were established between SNAQ scores, calorie intake and PM2.5 exposure. Overall findings suggested that long hours of PM2.5 exposure affect personal dietary intake, potentially increasing the risk of metabolic syndromes and other undesired health conditions. The current policy should be strengthened to safeguard the well-being of outdoor workers.

Deaths Attributable to Indoor PM2.5 in Urban China When Outdoor Air Meets 2021 WHO Air Quality Guidelines

The World Health Organization reduced the recommended level of annual mean PM_2.5 concentrations to 5 μg/m³ in 2021. Previously, the guideline was geared toward ambient air pollution, and now it explicitly applies to indoor air pollution. However, the disease burden attributed to different indoor emission sources has been overlooked, particularly in urban areas. Our objective was to estimate the mortality attributable to indoor PM_2.5 in urban areas in China. Our model estimated 711 thousand (584-823) deaths and 2.75 trillion (2.26-3.19) CNY economic losses attributable to PM_2.5 in urban China in 2019, in which indoor sources contributed 394 thousand (323-457) deaths and 1.53 trillion (1.25-1.77) CNY losses. There would still be 536 thousand (427-638) PM_2.5-attributable deaths and 2.07 trillion (1.65-2.47) CNY losses each year when the outdoor PM_2.5 is 5 μg/m³, of which 485 thousand (386-578) deaths and 1.87 trillion (1.49-2.23) CNY are attributable to indoor sources. Despite cleaner outdoor air and no solid fuels being used, considerable health hazards and economic losses are attributable to indoor PM_2.5. Measures to reduce PM_2.5 exposure in humans from both indoor and outdoor sources are required to achieve a substantial reduction in deaths.

Epidemiological characteristics of fractures of spine, hip, proximal humerus and forearm during the haze epidemic period

BACKGROUND

Air pollutants have an impact on the occurrence of spine fractures, hip fractures, proximal humerus fractures and forearm fractures. This study aimed at evaluating the short-term impact of particulate matter with aerodynamic diameters of less than 2.5 µm (PM_2.5) on the occurrence of those fractures in Shijiazhuang, Hebei, China.

METHODS

The daily meteorological, pollution, and fracture data of Shijiazhuang from 2014 to 2019 were collected. Distribution characteristics of fractures were described using descriptive epidemiological methods. The distributed lag nonlinear model (DLNM) was used to reveal the description of those fractures in the exposed and lag dimensions at the same time. Based on gender and age (<18 years old, 18-69 years old and >69 years old), stratified analysis was performed. Sensitivity analysis was performed to ascertain the robustness of the results.

RESULTS

Between 2014 and 2019, fracture incidences in Shijiazhuang exhibited an overall increasing trend, with an obvious seasonality. PM_2.5 was positively related to daily fracture cases and the effects were more obvious in women, adolescents and people of working age. When PM_2.5 concentrations increased by one interquartile range (IQR) (70 μg/m³), RR exhibited a unimodal distribution. Its peak appeared on the 16th day of lag (RR=1.005987, 95% CI:1.002472,1.009652), and the RRs were also statistically significant from the 10th to 22nd day of lag. Similarly, cumulative effects of each increase in the concentration of PM_2.5 IQR also showed a unimodal distribution. The largest cumulative effect occurred on the 28th day of lag (RR=1.084457, 95% CI:1.012207,1.161864), and the cumulative RRs were also statistically significant from the 19th day to 30nd days. In the dose-response relationship, as PM_2.5 concentrations increased, RR increased.

CONCLUSION

Year by year, fractures in Shijiazhuang City exhibited an increasing trend. PM_2.5 can affect the occurrence of those fractures. The impact on women, adolescents and people of working age is even greater. The supervision of PM_2.5 should be strengthened while large-scale emissions should be limited.

Impacts of particulate matter (PM2.5) on the health status of outdoor workers: observational evidence from Malaysia

Ambient air pollution is a significant contributor to disease burden, leading to an estimated 4.2 million premature deaths and 103.1 million disability-adjusted life years (DALYs) annually worldwide. As industrialization and urbanization surge in Asia, air pollution and its corresponding health issues follow suit. Findings on disease burden in developing countries are extremely scanty. This study aimed to determine the concentration of PM_2.5 and its impact on respiratory health of outdoor workers in Malaysia. A 2-cycled 3-month cohort study involving 440 participants was conducted. Workers' health status was assessed via (1) Total Ocular Symptom Score (TOSS), (2) Total Nasal Symptom Score (TNSS), (3) St. George's Respiratory Questionnaire (SGPQ), and (4) Asthma Control Test (ACT). The maximum PM_2.5 concentration was measured at 122.90 ± 2.07 µg/m³ during third week of August 2016. Meanwhile, the minimum concentration was measured at 57.47 ± 3.80 µg/m³ and 57.47 ± 1.64 µg/m³ during fourth week of July 2016 and first week of August 2017 respectively. Findings revealed that TOSS, TNSS, and SGPQ changes were significantly (p < 0.05) associated with the concentration of PM_2.5. Outdoor workers were more significantly (p < 0.05) affected by changes in PM_2.5 compared to indoor workers with a moderate correlation (r value ranged from 0.4 to 0.7). Ironically, no significant association was found between ACT assessment and PM_2.5. Collectively, our findings suggested that changes in the concentration of PM_2.5 threatened the respiratory health of outdoor workers. The existing policy should be strengthened and preventive measures to be enforced safeguarding health status of outdoor workers.

Environmental factors and risk of gout

Gout is a chronic disease with inflammatory arthritis caused by monosodium urate (MSU) crystals deposition, an elevated serum urate level (hyperuricaemia) is the critical factor leading to MSU crystals deposition and promoting the progression of gout. The onset and development of gout is generally the result of multiple factors, such as diet, heredity and environmental factors. Although genetics and diet are thought to play as major factors, a growing body of research evidence has highlighted that environmental factors also play a significant role in the onset and exacerbation of gout. Recent studies have shown that air pollutants such as particulate matter, sulfur dioxide (SO₂) and carbon monoxide (CO) may increase the risk of hospitalizations for gout, and that the changes in temperature and humidity may affect uric acid (UA) levels. There is also seasonal trend in gout. It has been demonstrated that environmental factors may induce or accelerate the production and release of pro-inflammatory mediators, causing an unbalance oxidative stress and systemic inflammation, and then participating in the overall process or a certain link of gout. Moreover, several environmental factors have shown the ability to induce the production urate and regulate the innate immune pathways, involving in the pathogenesis of gout. Nevertheless, the role of environmental factors in the etiology of gout remains unclear. In this review, we summarized the recent literatures and aimed to discuss the relationship between environmental factors (such as microclimate, season, ambient/indoor air pollution and extreme weather) and gout. We further discussed the inflammatory mechanisms of environmental factors and gout and the comprehensive effects of environmental factors on gout. We also made a prospect of the management and treatment of gout, with special consideration to environmental factors associated with gout.

Biomarkers for the adverse effects on respiratory system health associated with atmospheric particulate matter exposure

Large amounts of epidemiological evidence have confirmed the atmospheric particulate matter (PM_2.5) exposure was positively correlated with the morbidity and mortality of respiratory diseases. Nevertheless, its pathogenesis remains incompletely understood, probably resulting from the activation of oxidative stress, inflammation, altered genetic and epigenetic modifications in the lung upon PM_2.5 exposure. Currently, biomarker investigations have been widely used in epidemiological and toxicological studies, which may help in understanding the biologic mechanisms underlying PM_2.5-elicited adverse health outcomes. Here, the emerging biomarkers to indicate PM_2.5-respiratory system interactions were summarized, primarily related to oxidative stress (ROS, MDA, GSH, etc.), inflammation (Interleukins, FE_NO, CC16, etc.), DNA damage (8-OHdG, γH2AX, OGG1) and also epigenetic modulation (DNA methylation, histone modification, microRNAs). The identified biomarkers shed light on PM_2.5-elicited inflammation, fibrogenesis and carcinogenesis, thus may favor more precise interventions in public health. It is worth noting that some inconsistent findings may possibly relate to the inter-study differentials in the airborne PM_2.5 sample, exposure mode and targeted subjects, as well as methodological issues. Further research, particularly by -omics technique to identify novel, specific biomarkers, is warranted to illuminate the causal relationship between PM_2.5 pollution and deleterious lung outcomes.

Climate and air pollution exposure are associated with thyroid function parameters: a retrospective cross-sectional study

OBJECTIVES

There are still controversies about the impact of climatic and environmental factors on thyroid function parameters in healthy populations. We investigated the relationships between climate, air pollution exposure, and thyroid function fluctuations.

METHODS

We retrospectively reviewed 327,913 individuals attending routine health checks from December 2013 to December 2018. We analyzed the associations between thyroid function and climatic factors using Spearman's correlation analysis. We explored the relationships between thyroid function and air pollution exposure using multiple linear regression analysis, after adjusting for age, sex, season, and outdoor temperature. We also performed subgroup analyses by age and sex and sensitivity analyses of different anti-thyroid peroxidase antibody status.

RESULTS

Thyroid-stimulating hormone (TSH) and free triiodothyronine (FT3) were negatively associated with outdoor temperature (r = - 0.66, P < 0.001; r = - 0.55, P < 0.001), while free thyroxine (FT4) and FT4/FT3 were positively associated with temperature (r = 0.35, P < 0.001; r = 0.79, P < 0.001). An increase of 10 μg/m³ in fine particulate matter ≤ 2.5 μm (PM2.5) was associated with a decrease of 0.12 pmol/L in FT4 and an increase of 0.07 pmol/L in FT3 (both P < 0.01). FT4/FT3 was significantly negatively associated with PM2.5 (coefficient: - 0.06, P < 0.01). These results remained robust in hierarchical analyses and sensitivity analyses.

CONCLUSIONS

Thyroid function parameters are associated with climate and air pollution exposure. These factors may influence variations in thyroid function. Our results also highlight the importance of public health interventions to reduce air pollution.

Short-term effect of particular matter and sulfur dioxide exposure on asthma and/or chronic obstructive pulmonary disease hospital admissions in Center of Anatolia

We investigated the associations between the daily variations of coarse particulate matter (PM₁₀) and/or sulfur dioxide (SO₂) and hospital admissions for asthma and/or chronic obstructive pulmonary disease (COPD) diseases in Kirsehir, Center of Anatolia of Turkey. We analyzed the poison generalized linear model (GLM) to analyze the association between ambient air pollutants such as PM₁₀ and SO₂ and asthma and/or COPD admissions. We investigated single-lag days and multi-lag days for the risk increase in asthma, COPD, asthma, and/or COPD hospital admissions PM₁₀, SO₂, and PM₁₀ with SO₂ per 10 μg/m³. In single-lag day model a 10 μg/m³ increase in the current day (lag 0) concentrations of PM₁₀ and SO₂ corresponded to increase of 1.027 (95% CI:1.022-1.033) and 1.069 (95% CI:1.062, 1.077) for asthma. A 10 μg/m³ increase in the current day (lag 0) concentrations of PM₁₀ and SO₂ corresponded to increase of 1.029 (95% CI:1.022-1.035) and 1.065 (95% CI:1.056, 1.075) for COPD. A 10 μg/m³ increase in the current day (lag 0) concentrations of PM₁₀ and SO₂ corresponded to increase of 1.028 (95% CI:1.024-1.032) and 1.068 (95% CI:1.062, 1.074) for asthma and/or COPD. It was found that some lag structures were related with PM₁₀ and SO₂. Significant lags were detected in some lag structures from the previous first day until the previous eighth day (lag 1 to lag 7) in the asthma, COPD, and asthma and/or COPD hospital admissions in the model created with PM₁₀ with SO₂ both in the single-lag day model and in the multi-lag day model. Our study that used GLM in time series analysis showed that PM₁₀ and/or SO₂ short-term exposure in single-lag day and multi-lag day models was related with increased asthma, COPD, and asthma and/or COPD hospital admissions in the city between 2016 and 2019 until the previous-eighth day.

Physical activity attenuated association of air pollution with estimated 10-year atherosclerotic cardiovascular disease risk in a large rural Chinese adult population: A cross-sectional study

BACKGROUND

Although long-term exposure to air pollution and physical inactivity are linked to increased risk for atherosclerotic cardiovascular diseases (ASCVD), however, the interactive effect of air pollution and physical activity (PA) on high 10-year ASCVD risk is largely unknown.

METHODS

A total of 31,162 individuals aged 35-74 years were derived from the Henan Rural Cohort Study, after individuals with personal histories of ASCVD or missing data on predictors of high 10-year ASCVD risk were excluded. Concentrations of air pollutants (nitrogen dioxide (NO₂), particulate matter with an aerodynamics diameters ≤ 1.0 µm (PM₁), ≤2.5 µm (PM_2.5) or ≤10 µm (PM₁₀)) of individuals were estimated using a spatiotemporal model based on satellites data. The metabolic equivalent (MET) of PA of each individual was evaluated using the formula: duration (hour/time) × frequency/week × MET coefficient of each type of activity. Logistic regression models were used to analyze associations between air pollutants, PA and high 10-year ASCVD risk. Interaction plots were used to describe interactive effects of air pollutants and PA on high 10-year ASCVD risk.

RESULTS

Each 1 µg/m³ increase in PM₁, PM_2.5, PM₁₀ and NO₂ were related to a 4.4% (odds ratio (OR): 1.044, 95% confidence interval (CI): 1.034, 1.056), 9.1% (OR: 1.091, 95% CI: 1.079, 1.104), 4.6% (OR: 1.046, 95% CI: 1.040, 1.051) or 6.4% (OR: 1.064, 95% CI: 1.055, 1.072) increase in high 10-year ASCVD risk (all p < 0.001), respectively; each one unit-increase in PA MET (hour/day) value was related to a 1.8% (OR: 0.982, 95% CI: 0.980, 0.985) decrease in high 10-year ASCVD risk. Negative interactive effects of PA and PM₁, PM_2.5, PM₁₀ and NO₂ on high 10-year ASCVD risk were observed (all p < 0.001).

CONCLUSION

Exposure to high levels of air pollutants were related to increase high 10-year ASCVD risk and these associations were attenuated by PA, implying that PA may be an effective method to the prevention of high 10-year ASCVD risk in highly polluted rural regions.

Association between ambient air pollution and hospital admission for epilepsy in Eastern China

BACKGROUND

We aimed to study the short-term association between air pollutants and hospitalization for epilepsy in 47 hospitals from 10 cities in eastern China.

METHOD

We identified hospital epilepsy admissions in 2014 and 2015. A conditional Poisson regression model was used to examine the association between air pollutants and hospital admission, with temperature and relative humidity adjusted using the natural spline (ns) function. Pollutants included sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and particulate matter (PM). The association was stratified by sex, age, and geographic region in single-pollutant and two-pollutant models.

RESULTS

An interquartile (IQR) increase of NO₂ and CO on the concurrent day is correlated with an increased admission of 2.0% (0.5%, 3.6%) and 1.1% (0.1%, 2.1%), respectively. The association is stronger in children (≤18 years) and in northern China, but did not vary with sex. A positive association was also observed on the previous day for CO [1.5%, 95% confidence interval (CI): 0.3%, 2.6%], NO₂ (2.5%, 95% CI: 0.6%, 4.3%), and PM_2.5 (1.32%, 95% CI: 0.16%, 2.48%). Moving average concentration of 7 days for all pollutants was associated with decreased admission (CO: -1.29%, NO₂: -0.4.69%, SO₂:-2.12%, PM_2.5:-0.98%, PM₁₀:-1.70%).

CONCLUSION

Exposures to NO₂ and CO on concurrent days, and PM_2.5 on the previous day, are associated with increased epilepsy hospitalization, whereas cumulative exposure appeared protective.