Short-Term Exposure to Ambient Air Pollution and Asthma Mortality

Visual colorimetric label for real-time monitoring of SO2 concentration change in grape and mango during storage

Sulfur dioxide (SO2) is widely utilized as a preservative in food transportation and storage, but excessive consumption poses health risks. This study presents a novel and efficient method for the real-time detection of SO2 using a sensor named TK, synthesized from triphenylamine and 2-cyanomethyl-1-methyl-quinolinium. The core mechanism involves the Michael addition reaction of the CC bond in TK with SO2, which disrupts the intramolecular charge transfer process, resulting in a significant color change and a blue shift in fluorescence emission. Methodologically, the sensor's response was quantified by the change in fluorescence intensity ratio (I425/I647) within a SO2 concentration range of 0-180 μM. The sensor exhibited high sensitivity and selectivity. For practical application, TK was incorporated into hydrophilic polyvinyl alcohol to create a smart label capable of visual colorimetry and fluorescence analysis. SO2 concentration changes were monitored by using this label, demonstrated by the color transition from burgundy red to colorless, yielding a maximum color difference (ΔE) of 73.6. The smart label was successfully used to monitor the quality of various grapes and mangoes during long-term storage, providing a reliable, equipment-independent method suitable for household use. The study offers a new tool for enhancing food safety and mitigating health risks associated with SO2 exposure.

Interactive effects of atmospheric oxidising pollutants and heat waves on the risk of residential mortality

BACKGROUND

The impact of heat waves and atmospheric oxidising pollutants on residential mortality within the framework of global climate change has become increasingly important.

OBJECTIVE

In this research, the interactive effects of heat waves and oxidising pollutants on the risk of residential mortality in Fuzhou were examined. Methods We collected environmental, meteorological, and residential mortality data in Fuzhou from 1 January 2016, to 31 December 2021. We then applied a generalised additive model, distributed lagged nonlinear model, and bivariate three-dimensional model to investigate the effects and interactions of various atmospheric oxidising pollutants and heat waves on the risk of residential mortality.

RESULTS

Atmospheric oxidising pollutants increased the risk of residential mortality at lower concentrations, and O3 and Ox were positively associated with a maximum risk of 2.19% (95% CI: 0.74-3.66) and 1.29% (95% CI: 0.51-2.08). The risk of residential mortality increased with increasing temperature, with a strong and long-lasting effect and a maximum cumulative lagged effect of 1.11% (95% CI: 1.01, 1.23). Furthermore, an interaction between atmospheric oxidising pollutants and heat waves may have occurred: the larger effects in the longest cumulative lag time on residential mortality per 10 µg/m3 increase in O3, NO2 and Ox during heat waves compared to non-heat waves were [-3.81% (95% CI: -14.82, 8.63)]; [-0.45% (95% CI: -2.67, 1.81)]; [67.90% (95% CI: 11.55, 152.71)]; 16.37% (95% CI: 2.43, 32.20)]; [-3.00% (95% CI: -20.80, 18.79)]; [-0.30% (95% CI: -3.53, 3.04)]. The risk on heat wave days was significantly higher than that on non-heat wave days and higher than the separate effects of oxidising pollutants and heat waves.

CONCLUSIONS

Overall, we found some evidence suggesting that heat waves increase the impact of oxidising atmospheric pollutants on residential mortality to some extent.

Short-term exposure to PM2.5 constituents, extreme temperature events and stroke mortality

BACKGROUND

Fine particulate matter (PM2.5) pollution and extreme temperature events (ETEs) are main environmental threats to human health. Elevated stroke mortality has been growingly linked to PM2.5 mass exposure, while its relationship with PM2.5 constituents was extensively unstudied across the globe. Additionally, no prior assessments have investigated the interactive effects of PM2.5 constituents and ETEs on stroke mortality.

METHODS

Province-wide records of 320,372 stroke deaths collected in eastern China during 2016-2019 were analyzed using an individual-level time-stratified case-crossover design. Daily gridded estimates of PM2.5 mass and its major constituents (i.e., black carbon [BC], organic matter [OM], ammonium [NH4+], sulfate [SO42-], and nitrate [NO3-]) were assigned to stroke cases on case days and control days at the residential address. We assessed 12 ETEs defined by multiple combinations of air temperature thresholds (2.5-10th percentiles for cold spell, 90-97.5th percentiles for heat wave) and durations (2-4 days). Conditional logistic regression model was applied to investigate associations of short-term exposure to PM2.5 constituents and ETEs with stroke mortality. Odds ratio and its 95% confidence interval (CI) were assessed for an interquartile range (IQR) increase in each PM2.5 constituent and on ETEs days compared with non-ETEs days. Additive interactive effects were quantitatively evaluated via relative excess odds due to interaction (REOI), attributable proportion due to interaction (AP), and synergy index (SI).

RESULTS

Elevated overall stroke mortality was significantly related to PM2.5 constituents, with the largest odds observed for NO3- (1.04, 95% CI: 1.03-1.04, IQR = 11.25 μg/m3), followed by OM (1.03, 1.03-1.04, IQR = 7.97 μg/m3), NH4+ (1.03, 1.02-1.04, IQR = 6.66 μg/m3), BC (1.03, 1.02-1.03, IQR = 1.41 μg/m3), and SO42- (1.03, 1.02-1.03, IQR = 6.67 μg/m3). Overall, higher risks of stroke mortality were identified in analyses using more rigorous thresholds and lengthened durations of ETEs definitions, ranging from 1.19 (1.17-1.21) to 1.55 (1.51-1.60) for heat wave, and 1.03 (1.02-1.05) to 1.11 (1.08-1.15) for cold spell, respectively. We observed consistent evidence for the synergistic effects of heat wave and PM2.5 constituents on both ischemic and hemorrhagic stroke mortality, where compound exposures to heat wave and secondary inorganic aerosols (i.e., NO3-, SO42-, and NH4+) posed greater increases in risk (0.23< REOI <0.81, 0.16< AP <0.39, and 2.63< SI <8.19).

CONCLUSIONS

Short-term exposure to both PM2.5 constituents and ETEs were associated with heightened stroke mortality, and heat wave may interact synergistically with PM2.5 constituents to trigger stroke deaths.

Key factors in epidemiological exposure and insights for environmental management: Evidence from meta-analysis

In recent years, the precision of exposure assessment methods has been rapidly improved and more widely adopted in epidemiological studies. However, such methodological advancement has introduced additional heterogeneity among studies. The precision of exposure assessment has become a potential confounding factors in meta-analyses, whose impacts on effect calculation remain unclear. To explore, we conducted a meta-analysis to integrate the long- and short-term exposure effects of PM2.5, NO2, and O3 on all-cause, cardiovascular, and respiratory mortality in the Chinese population. Literature was identified through Web of Science, PubMed, Scopus, and China National Knowledge Infrastructure before August 28, 2023. Sub-group analyses were performed to quantify the impact of exposure assessment precisions and pollution levels on the estimated risk. Studies achieving merely city-level resolution and population exposure are classified as using traditional assessment methods, while those achieving sub-kilometer simulations and individual exposure are considered finer assessment methods. Using finer assessment methods, the RR (under 10 μg/m3 increment, with 95% confidence intervals) for long-term NO2 exposure to all-cause mortality was 1.13 (1.05-1.23), significantly higher (p-value = 0.01) than the traditional assessment result of 1.02 (1.00-1.03). Similar trends were observed for long-term PM2.5 and short-term NO2 exposure. A decrease in short-term PM2.5 levels led to an increase in the RR for all-cause and cardiovascular mortality, from 1.0035 (1.0016-1.0053) and 1.0051 (1.0021-1.0081) to 1.0055 (1.0035-1.0075) and 1.0086 (1.0061-1.0111), with weak between-group significance (p-value = 0.13 and 0.09), respectively. Based on the quantitative analysis and literature information, we summarized four key factors influencing exposure assessment precision under a conceptualized framework: pollution simulation resolution, subject granularity, micro-environment classification, and pollution levels. Our meta-analysis highlighted the urgency to improve pollution simulation resolution, and we provide insights for researchers, policy-makers and the public. By integrating the most up-to-date epidemiological research, our study has the potential to provide systematic evidence and motivation for environmental management.

Ambient air pollution and hospital admission for interstitial lung diseases: A multicenter hospital-based case-crossover study

Interstitial lung diseases (ILDs) lead to increased morbidity and premature deaths, imposing a significant burden on public health worldwide. Recently, several studies have linked ambient air pollution with the acute exacerbation of certain ILDs, but the evidence remains limited and inconclusive. With a multicenter hospital-based case-crossover design, we investigated 9128 patients who resided in Jiangsu province, China, and were admitted for ILDs between 2019 and 2022. Residential exposure to particulate matter with an aerodynamic diameter ≤ 2.5 µm (PM2.5), PM10, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) was assessed using our validated grid datasets. We fitted conditional logistic regression models to examine associations of exposure to air pollutants with ILD admission. A 10 µg/m3 increment of exposure to SO2 and NO2 was positively associated with a 16.18 % (95 % confidence interval [CI]: 3.79 %, 30.03 %) and 4.06 % (0.75 %, 7.49 %) increase in odds of ILD admission, respectively. All these associations appeared to be linear and the association of SO2 exposure was significantly stronger among older adults. We estimated that over 10 % of ILD admissions could be attributable to exposure to SO2 and NO2. This study provides compelling evidence on the association of exposure to ambient air pollutants (including SO2 and NO2) with an increased odds of ILD hospitalizations. Our findings indicate that SO2 and NO2 exposures can lead to the exacerbation of ILDs, especially in elderly, and that the disease burden is considerable.

Influence and distinctions of particulate matter exposure across varying etiotypes in chronic obstructive pulmonary disease (COPD) mouse model

BACKGROUND

Air pollution, notably particulate matter (PM), significantly impacts chronic respiratory disease such chronic obstructive pulmonary disease (COPD). Although asthma-COPD overlap (ACO), considered one of the COPD etiotype, is associated with greater severity in both symptoms and outcomes, effects of PM exposure remain unclear. Thus, this study aimed to evaluate impact of PM on chronic airway disease animal models.

METHODS

We established two distinct COPD etiotypes, cigarette smoking-related COPD (COPD-C) and COPD with asthma (COPD-A), using porcine pancreatic elastase (PPE) for COPD-C and a combination of PPE with ovalbumin for COPD-A. To reflect smoking influence, cigarette smoking extract was administered to both disease models. To assess impact of PM exposure, bronchoalveolar lavage fluid (BALF), proinflammatory cytokines, lung histology, and cellular damage mechanisms were analyzed.

RESULTS

In the COPD-A model, cell counts and type 2 cytokines were elevated in BALF independent of PM exposure. All models exhibited increased lung inflammation and emphysema due to PM exposure. Expression levels of apoptosis-related protein B-cell lymphoma protein 2 (Bcl-2) associated X (Bax) showed an inclination to increase with PM exposure. In the COPD-A model, decreased expression of basal nuclear factor erythroid-derived 2-like 2 (Nrf-2) and increased production of reactive oxygen species (ROS) due to PM exposure were noted.

CONCLUSION

We developed two distinct models for the etiotypes of COPD and found increased vulnerability to cell damage in COPD-A after PM exposure. Moreover, the control group displayed escalated airway inflammation and emphysema due to PM exposure, substantiating the risk of respiratory diseases.

Fritillaria steroidal alkaloids and their multi-target therapeutic mechanisms: insights from network pharmacology

Medicinal Fritillaria herbs, known for their rich content of steroidal alkaloids, have emerged as promising candidates in the treatment of chronic diseases due to their diverse pharmacological properties. Leveraging advancements in network pharmacology and molecular docking, this study explores the multi-target mechanisms through which these alkaloids exert therapeutic effects. The integration of bioinformatics, systems biology, and pharmacology in drug discovery has provided insights into the molecular interactions and pathways influenced by Fritillaria steroidal alkaloids. This review synthesizes comprehensive literature from 1985 to 2024, revealing the potential of these compounds in addressing respiratory diseases, inflammation, and cancer. The integration of traditional Chinese medicine (TCM) with modern pharmacological techniques underscores the relevance of these compounds in next-generation drug discovery. While initial findings are promising, further empirical validation is necessary to fully harness the therapeutic potential of Fritillaria steroidal alkaloids.

Exposure to mixtures of PM2.5 components and term premature rupture of membranes: a case-crossover study in Shijiazhuang, China

This study aims to explore the acute effects of short-term exposure to PM2.5 components and their mixture on PROM. Counts of hospital admissions due to PROM were collected at the Fourth Hospital of Shijiazhuang. The associations between the PROM and PM2.5 components was examined using a time-stratified case-crossover approach. The overall effects of components on TPROM were examined using the BKMR. During the study period 30,709 cases of PROMwere identified. The relative risks and the 95% CI of TPROM were 1.013 (1.002, 1.028) and 1.015 (1.003, 1.028) associated with per interquartile range increase in nitrate and ammonium ion on the current day and they were 1.007 (1.001, 1.013) and 1.003 (1.000, 1.005) on the previous day. The results from the BKMR models showed a higher risk of TPROM was associated with exposure to mixtures, in which, nitrate and organic matter were the main contributors to the overall effect.

The frequency of asthma and its related factors: results of the enrolment phase of Tabari cohort study

INTRODUCTION

A large portion of the world's population has asthma. This study aimed to ascertain asthma prevalence and related factors in the Tabari cohort study (TCS).

METHODS

The TCS included 10,255 35-70-year-olds from urban and mountainous Sari (northern Iran) between June 2015 and November 2017. Education, occupation, domicile, socioeconomic position, history of psychiatric disorders, smoking (including hookah smoking), opium usage, and daily physical activity level were determined.

RESULTS

The final analysis included 9939 individuals. The asthma rate was 7.4%. Multiple factors increased asthma risk, according to statistical analysis. These factors included being female (OR, 1.337; 95% CI, 1.142-1.565), retired (OR, 1.553; 95% CI, 1.205-2.002), living in the city (OR, 1.268; 95% CI, 1.083-1.484), using opioids (OR, 1.689; 95% CI, 1.299-2.197), having lower socioeconomic status (SES) (OR, 0.723; 95% CI, 0.579-0.903), history of psychiatric disorders (OR, 2.313; 95% CI, 1.826-2.930), and aged 60-70 (OR, 2.325; 95% CI, 1.765-3.064), and BMI above 30 kg/m2 (OR, 1.499; 95% CI, 1.220-1.841). Several factors increased asthma probability in multivariate regression analysis. These factors include being female (OR = 1.389, p = 0.015), ages between 60 and 70 (OR = 2.034, p < 0.001), using opioids (OR = 1.940, p < 0.001), lower SES (OR = 0.738, p = 0.012), history of psychiatric disorders (OR = 2.035, p < 0.001), BMI above 30 kg/m2 (OR = 1.518, p < 0.001), and being a smoker (OR = 1.337, p = 0.056).

CONCLUSION

This study has identified that the prevalence of asthma in the Tabari cohort group is high. In addition, it was demonstrated that various factors are related to asthma.

Controlled human exposures to diesel exhaust or particle-depleted diesel exhaust with allergen modulates transcriptomic responses in the lung

The evidence associating traffic-related air pollution (TRAP) with allergic asthma is growing, but the underlying mechanisms for this association remain unclear. The airway epithelium is the primary tissue exposed to TRAP, hence understanding its interactions with TRAP and allergen is important. Diesel exhaust (DE), a paradigm of TRAP, consists of particulate matter (PM) and gases. Modern diesel engines often have catalytic diesel particulate filters to reduce PM output, but these may increase gaseous concentrations, and their benefits on human health cannot be assumed. We conducted a randomized, double-blinded, crossover study using our unique in vivo human exposure system to investigate the effects of DE and allergen co-exposure, with or without particle depletion as a proxy for catalytic diesel particulate filters, on the airway epithelial transcriptome. Participants were exposed for 2 h before an allergen inhalation challenge, with each receiving filtered air and saline (FA-S), filtered air and allergen (FA-A), DE and allergen (DE-A), or particle-depleted DE and allergen (PDDE-A), over four different occasions, each separated by a 4-week washout period. Endobronchial brushings were collected 48 h after each exposure, and total RNA was sequenced. Differentially expressed genes (DEGs) were identified using DESeq2, followed by GO enrichment and pathway analysis. FA-A, DE-A, and PDDE-A exposures significantly modulated genes relative to FA-S, with 462 unique DEGs identified. FA-A uniquely modulated the highest number (↑178, ↓155), followed by DE-A (↑44, ↓23), and then PDDE-A exposure (↑15, ↓2); 6 DEGs (↑4, ↓2) were modulated by all three conditions. Exposure to PDDE-A resulted in modulation of 285 DEGs compared to DE-A exposure, further revealing 26 biological process GO terms, including "cellular response to chemokine" and "inflammatory response". The transcriptional epithelial response to diesel exhaust and allergen co-exposure is enriched in inflammatory mediators, the pattern of which is altered upon particle depletion.

Intermittent ozone inhalation during house dust mite-induced sensitization primes for adverse asthma phenotype

The ability of air pollution to induce acute exacerbation of asthma is well documented. However, the ability of ozone (O3), the most reactive gaseous component of air pollution, to function as a modulator during sensitization is not well established. C57BL/6 J male mice were intranasally sensitized to house dust mite (HDM) (40 μg/kg) for 3 weeks on alternate days in parallel with once-a-week O3 exposure (1 ppm). Mice were euthanized 24 h following the last HDM challenge. Lung lavage, histology, lung function (both forced oscillation and forced expiration-based), immune cell profiling, inflammation (pulmonary and systemic), and immunoglobulin production were assessed. Compared to HDM alone, HDM + O3 leads to a significant increase in peribronchial inflammation (p < 0.01), perivascular inflammation (p < 0.001) and methacholine-provoked large airway hyperreactivity (p < 0.05). Serum total IgG and IgE and HDM-specific IgG1 were 3-5 times greater in HDM + O3 co-exposure compared to PBS and O3-exposed groups. An increase in activated/mature lung total and monocyte-derived dendritic cells (p < 0.05) as well as T-activated, and T memory lymphocyte subset numbers (p < 0.05) were noted in the HDM + O3 group compared to HDM alone group. Concurrent O3 inhalation and HDM sensitization also caused significantly greater (p < 0.05) lung tissue interleukin-17 pathway gene expression and mediator levels in the serum. Redox imbalance was manifested by impaired lung antioxidant defense and increased oxidants. O3 inhalation during allergic sensitization coalesces in generating a significantly worse TH17 asthmatic phenotype.

Air pollution, dysbiosis and diseases: pneumonia, asthma, COPD, lung cancer and irritable bowel syndrome

With substantial effects on human health, air pollution has become a major global concern. Air pollution has been linked to numerous gastrointestinal and respiratory diseases with increasing mortalities. The gut and respiratory dysbiosis brought about by air pollution has recently received much attention. This review attempts to provide an overview of the types of air pollutants, their sources, their impact on the respiratory and gut dysbiotic patterns and their correlation with five major diseases including pneumonia, asthma, COPD, lung cancer and irritable bowel syndrome. Deeper insights into the links between pollutants, dysbiosis and disease may pave the way for novel diagnostic biomarkers for prognosis and early detection of these diseases, as well as ways to ease the disease burden.

Association of short-term exposure to ambient fine particulate matter and ozone with outpatient visits for anxiety disorders: A hospital-based case-crossover study in South China

BACKGROUND

The short-term adverse effects of ambient fine particulate matter (PM2.5) and ozone (O3) on anxiety disorders (ADs) remained inconclusive.

METHODS

We applied an individual-level time-stratified case-crossover study, which including 126,112 outpatient visits for ADs during 2019-2021 in Guangdong province, China, to investigate the association of short-term exposure to PM2.5 and O3 with outpatient visits for ADs, and estimate excess outpatient visits in South China. Daily residential air pollutant exposure assessments were performed by extracting grid data (spatial resolution: 1 km × 1 km) from validated datasets. We employed the conditional logistic regression model to quantify the associations and excess outpatient visits.

RESULTS

The results of the single-pollutant models showed that each 10 μg/m3 increase of PM2.5 and O3 exposures was significantly associated with a 3.14 % (95 % confidence interval: 2.47 %, 3.81 %) and 0.88 % (0.49 %, 1.26 %) increase in odds of outpatient visits for ADs, respectively. These associations remained robust in 2-pollutant models. The proportion of outpatient visits attributable to PM2.5 and O3 exposures was up to 7.20 % and 8.93 %, respectively. Older adults appeared to be more susceptible to PM2.5 exposure, especially in cool season, and subjects with recurrent outpatient visits were more susceptible to O3 exposure.

LIMITATION

As our study subjects were from one single hospital in China, it should be cautious when generalizing our findings to other regions.

CONCLUSION

Short-term exposure to ambient PM2.5 and O3 was significantly associated with a higher odds of outpatient visits for ADs, which can contribute to considerable excess outpatient visits.

Associations of personal PM2.5-bound heavy metals and heavy metal mixture with lung function: Results from a panel study in Chinese urban residents

BACKGROUND

There are a few reports on the associations between fine particulate matter (PM2.5)-bound heavy metals and lung function.

OBJECTIVES

To evaluate the associations of single and mixed PM2.5-bound heavy metals with lung function.

METHODS

This study included 316 observations of 224 Chinese adults from the Wuhan-Zhuhai cohort over two study periods, and measured participants' personal PM2.5-bound heavy metals and lung function. Three linear mixed models, including the single constituent model, the PM2.5-adjusted constituent model, and the constituent residual model were used to evaluate the association between single metal and lung function. Mixed exposure models including Bayesian kernel machine regression (BKMR) model, weighted quantile sum (WQS) model, and Explainable Machine Learning model were used to assess the relationship between PM2.5-bound heavy metal mixtures and lung function.

RESULTS

In the single exposure analyses, significant negative associations of PM2.5-bound lead, antimony, and cadmium with peak expiratory flow (PEF) were observed. In the mixed exposure analyses, significant decreases in forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC), maximal mid-expiratory flow (MMF), and forced expiratory flow at 75% of the pulmonary volume (FEF75) were associated with the increased PM2.5-bound heavy metal mixture. The BKMR models suggested negative associations of PM2.5-bound lead and antimony with lung function. In addition, PM2.5-bound copper was positively associated with FEV1/FVC, MMF, and FEF75. The Explainable Machine Learning models suggested that FEV1/FVC, MMF, and FEF75 decreased with the elevated PM2.5-bound lead, manganese, and vanadium, and increased with the elevated PM2.5-bound copper.

CONCLUSIONS

The negative relationships were detected between PM2.5-bound heavy metal mixture and FEV1/FVC, MMF, as well as FEF75. Among the PM2.5-bound heavy metal mixture, PM2.5-bound lead, antimony, manganese, and vanadium were negatively associated with FEV1/FVC, MMF, and FEF75, while PM2.5-bound copper was positively associated with FEV1/FVC, MMF, and FEF75.

Short-term exposure to ambient fine particulate matter constituents and myocardial infarction mortality

Short-term ambient fine particulate matter (PM2.5) exposure has been related to an increased risk of myocardial infarction (MI) death, but which PM2.5 constituents are associated with MI death and to what extent remain unclear. We aimed to explore the associations of short-term exposure to PM2.5 constituents with MI death and evaluate excess mortality. We conducted a time-stratified case-crossover study on 237,492 MI decedents in Jiangsu province, China during 2015-2021. Utilizing a validated PM2.5 constituents grid dataset at 1 km spatial resolution, we estimated black carbon (BC), organic carbon (OC), sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), and chloride (Cl-) exposure by extracting daily concentrations grounding on the home address of each subject. We employed conditional logistic regression models to evaluate the exposure-response relationship between PM2.5 constituents and MI death. Overall, per interquartile range (IQR) increase of BC (lag 06-day; IQR: 1.75 μg/m3) and SO42- (lag 04-day; IQR: 5.06 μg/m3) exposures were significantly associated with a 3.91% and 2.94% increase in odds of MI death, respectively, and no significant departure from linearity was identified in the exposure-response curves for BC and SO42-. If BC and SO42- exposures were reduced to theoretical minimal risk exposure concentration (0.89 μg/m3 and 1.51 μg/m3), an estimate of 4.55% and 4.80% MI deaths would be avoided, respectively. We did not find robust associations of OC, NO3-, NH4+, and Cl- exposures with MI death. Individuals aged ≥80 years were more vulnerable to PM2.5 constituent exposures in MI death (p for difference <0.05). In conclusion, short-term exposure to PM2.5-bound BC and SO42- was significantly associated with increased odds of MI death and resulted in extensive excess mortality, notably in older adults. Our findings emphasized the necessity of reducing toxic PM2.5 constituent exposures to prevent deaths from MI and warranted further studies on the relative contribution of specific constituents.

Differing associations of PM2.5 exposure with systolic and diastolic blood pressures across exposure durations in a predominantly non-Hispanic Black cohort

Environmental health research has suggested that fine particulate matter (PM2.5) exposure can lead to high blood pressures, but it is unclear whether the impacts remain the same for systolic and diastolic blood pressures (SBP and DBP). This study aimed to examine whether the effects of PM2.5 exposure on SBP and DBP differ using data from a predominantly non-Hispanic Black cohort collected between 2013 and 2019 in the US. PM2.5 exposure was assessed based on a satellite-derived model across exposure durations from 1 to 36 months. The average PM2.5 exposure level was between 9.5 and 9.8 μg/m3 from 1 through 36 months. Mixed effects models were used to estimate the association of PM2.5 with SBP, DBP, and related hypertension types, adjusted for potential confounders. A total of 6381 participants were included. PM2.5 exposure was positively associated with both SBP and DBP. The association magnitudes depended on exposure durations. The association with SBP was null at the 1-month duration (β = 0.05, 95% CI: - 0.23, 0.33), strengthened as duration increased, and plateaued at the 24-month duration (β = 1.14, 95% CI: 0.54, 1.73). The association with DBP started with β = 0.29 (95% CI: 0.11, 0.47) at the 1-month duration, and plateaued at the 12-month duration (β = 1.61, 95% CI: 1.23, 1.99). PM2.5 was associated with isolated diastolic hypertension (12-month duration: odds ratio = 1.20, 95% CI: 1.07, 1.34) and systolic-diastolic hypertension (12-month duration: odds ratio = 1.18, 95% CI: 1.10, 1.26), but not with isolated systolic hypertension. The findings suggest DBP is more sensitive to PM2.5 exposure and support differing effects of PM2.5 exposure on SBP and DBP. As elevation of SBP and DBP differentially predict CVD outcomes, this finding is relevant for prevention and treatment.

Increased mortality risk from airborne exposure to polycyclic aromatic hydrocarbons

BACKGROUND

The potential health effects of airborne polycyclic aromatic hydrocarbons (PAHs) among general population remained extensively unstudied. This study sought to investigate the association of short-term exposure to low-level total and 7 carcinogenic PAHs with mortality risk.

METHODS

We conducted an individual-level time-stratified case-crossover study in Jiangsu province of eastern China, by investigating over 2 million death cases during 2016-2019. Daily concentrations of total PAH and its 7 carcinogenic species including benzo[a]anthracene (BaA), benzo[a]pyrene (BaP), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), chrysene (Chr), dibenz[a,h]anthracene (DahA), and indeno[1,2,3-cd]pyrene (IcdP), predicted by well-validated spatiotemporal models, were assigned to death cases according to their residential addresses. We estimated mortality risk associated with short-term exposure to increase of an interquartile range (IQR) for aforementioned PAHs using conditional logistic regression.

RESULTS

An IQR increase (16.9 ng/m3) in 2-day (the current and prior day) moving average of total PAH concentration was associated with risk increases of 1.90% (95% confidence interval [CI]: 1.71-2.09) in all-cause mortality, 1.90% (95% CI: 1.70-2.10) in nonaccidental mortality, 2.01% (95% CI: 1.72-2.29) in circulatory mortality, and 2.53% (95% CI: 2.03-3.02) in respiratory mortality. Risk increases of cause-specific mortality ranged between 1.42-1.90% for BaA (IQR: 1.6 ng/m3), 1.94-2.53% for BaP (IQR: 1.6 ng/m3), 2.45-3.16% for BbF (IQR: 2.8 ng/m3), 2.80-3.65% for BkF (IQR: 1.0 ng/m3), 1.36-1.77% for Chr (IQR: 1.8 ng/m3), 0.77-1.24% for DahA (IQR: 0.8 ng/m3), and 2.96-3.85% for IcdP (IQR: 1.7 ng/m3).

CONCLUSIONS

This study provided suggested evidence for heightened mortality risk in relation to short-term exposure to airborne PAHs in general population. Our findings suggest that airborne PAHs may pose a potential threat to public health, emphasizing the need of more population-based evidence to enhance the understanding of health risk under the low-dose exposure scenario.

Cancer mortality risk from short-term PM2.5 exposure and temporal variations in Brazil

Although some studies have found that short-term PM2.5 exposure is associated with lung cancer deaths, its impact on other cancer sites is unclear. To answer this research question, this time-stratified case-crossover study used individual cancer death data between January 1, 2000, and December 31, 2019, extracted from the Brazilian mortality information system to quantify the associations between short-term PM2.5 exposure and cancer mortality from 25 common cancer sites. Daily PM2.5 concentration was aggregated at the municipality level as the key exposure. The study included a total of 34,516,120 individual death records, with the national daily mean PM2.5 exposure 15.3 (SD 4.3) μg/m3. For every 10-μg/m3 increase in three-day average PM2.5 exposure, the odds ratio (OR) for all-cancer mortality was 1.04 (95% CI 1.03-1.04). Apart from all-cancer deaths, PM2.5 exposure may impact cancers of oesophagus (1.04, 1.00-1.08), stomach (1.05, 1.02-1.08), colon-rectum (1.04, 1.01-1.06), lung (1.04, 1.02-1.06), breast (1.03, 1.00-1.06), prostate (1.07, 1.04-1.10), and leukaemia (1.05, 1.01-1.09). During the study period, acute PM2.5 exposure contributed to an estimated 1,917,994 cancer deaths, ranging from 0 to 6,054 cases in each municipality. Though there has been a consistent downward trend in PM2.5-related all-cancer mortality risks from 2000 to 2019, the impact remains significant, indicating the continued importance of cancer patients avoiding PM2.5 exposure. This nationwide study revealed a notable association between acute PM2.5 exposure and heightened overall and site-specific cancer mortality for the first time to our best knowledge. The findings suggest the importance of considering strategies to minimize such exposure in cancer care guidelines. ENVIRONMENTAL IMPLICATION: The 20-year analysis of nationwide death records in Brazil revealed that heightened short-term exposure to PM2.5 is associated with increased cancer mortality at various sites, although this association has gradually decreased over time. Despite the declining impact, the research highlights the persistent adverse effects of PM2.5 on cancer mortality, emphasizing the importance of continued research and preventive measures to address the ongoing public health challenges posed by air pollution.

Formaldehyde exacerbates inflammation and biases T helper cell lineage commitment through IFN-γ/STAT1/T-bet pathway in asthma

The correlation between formaldehyde (FA) exposure and prevalence of asthma has been widely reported. However, the underlying mechanism is still not fully understood. FA exposure at 2.0 mg/m3 was found to exacerbate asthma in OVA-induced murine models. IFN-γ, the cytokine produced by T helper 1 (Th1) cells, was significantly induced by FA in serum and bronchoalveolar lavage fluid (BALF) of asthmatic mice, which was different from cytokines secreted by other Th cells. The observation was also confirmed by mRNA levels of Th marker genes in CD4+ T cells isolated from BALF. In addition, increased production of IFN-γ and expression of T-bet in Jurkat T cells primed with phorbol ester and phytohaemagglutinin were also observed with 100 μM FA treatment in vitro. Upregulated STAT1 phosphorylation, T-bet expression and IFN-γ production induced by FA was found to be restrained by STAT1 inhibitor fludarabine, indicating that FA promoted Th1 commitment through the autocrine IFN-γ/STAT1/T-bet pathway in asthma. This work not only revealed that FA could bias Th lineage commitment to exacerbate allergic asthma, but also identified the signaling mechanism of FA-induced Th1 differentiation, which may be utilized as the target for development of interfering strategies against FA-induced immune disorders.

Short-term ozone exposure and cancer mortality in Brazil: A nationwide case-crossover study

Exposure to ambient ozone (O3) is linked to increased mortality risks from various diseases, but epidemiological investigations delving into its potential implications for cancer mortality are limited. We aimed to examine the association between short-term O3 exposure and site-specific cancer mortality and investigate vulnerable subgroups in Brazil. In total 3,459,826 cancer death records from 5570 Brazilian municipalities between 2000 and 2019, were included. Municipal average daily O3 concentration was calculated from a global estimation at 0.25°×0.25° spatial resolution. The time-stratified case-crossover design was applied to assess the O3-cancer mortality association. Subgroup analyses by age, sex, season, time-period, region, urban hierarchy, climate classification, quantiles of GDP per capita and illiteracy rates were performed. A linear and non-threshold exposure-response relationship was observed for short-term exposure to O3 with cancer mortality, with a 1.00% (95% CI: 0.79%-1.20%) increase in all-cancer mortality risks for each 10-μg/m3 increment of three-day average O3. Kidney cancer was most strongly with O3 exposure, followed by cancers of the prostate, stomach, breast, lymphoma, brain and lung. The associated cancer risks were relatively higher in the warm season and in southern Brazil, with a decreasing trend over time. When restricting O3 concentration to the national minimum value during 2000-2019, a total of 147,074 (116,690-177,451) cancer deaths could be avoided in Brazil, which included 17,836 (7014-28,653) lung cancer deaths. Notably, these associations persisted despite observed adaptation within the Brazilian population, highlighting the need for a focus on incorporating specific measures to mitigate O3 exposure into cancer care recommendations.

Assessing the Impact of Non-Exhaust Emissions on the Asthmatic Airway (IONA) Protocol for a Randomised Three-Exposure Crossover Study

BACKGROUND

People living with asthma are disproportionately affected by air pollution, with increased symptoms, medication usage, hospital admissions, and the risk of death. To date, there has been a focus on exhaust emissions, but traffic-related air pollution (TRAP) can also arise from the mechanical abrasion of tyres, brakes, and road surfaces. We therefore created a study with the aim of investigating the acute impacts of non-exhaust emissions (NEEs) on the lung function and airway immune status of asthmatic adults.

METHODS

A randomised three-condition crossover panel design will expose adults with asthma using a 2.5 h intermittent cycling protocol in a random order at three locations in London, selected to provide the greatest contrast in the NEE components within TRAP. Lung function will be monitored using oscillometry, fractional exhaled nitric oxide, and spirometry (the primary outcome is the forced expiratory volume in one second). Biomarkers of inflammation and airborne metal exposure will be measured in the upper airway using nasal lavage. Symptom responses will be monitored using questionnaires. Sources of exhaust and non-exhaust concentrations will be established using source apportionment via the positive matrix factorisation of high-time resolution chemical measures conducted at the exposure sites.

DISCUSSION

Collectively, this study will provide us with valuable information on the health effects of NEE components within ambient PM2.5 and PM10, whilst establishing a biological mechanism to help contextualise current epidemiological observations.

The impact of outdoor pollution and extreme temperatures on asthma-related outcomes: A systematic review for the EAACI guidelines on environmental science for allergic diseases and asthma

Air pollution is one of the biggest environmental threats for asthma. Its impact is augmented by climate change. To inform the recommendations of the EAACI Guidelines on the environmental science for allergic diseases and asthma, a systematic review (SR) evaluated the impact on asthma-related outcomes of short-term exposure to outdoor air pollutants (PM2.5, PM10, NO2, SO2, O3, and CO), heavy traffic, outdoor pesticides, and extreme temperatures. Additionally, the SR evaluated the impact of the efficacy of interventions reducing outdoor pollutants. The risk of bias was assessed using ROBINS-E tools and the certainty of the evidence by using GRADE. Short-term exposure to PM2.5, PM10, and NO2 probably increases the risk of asthma-related hospital admissions (HA) and emergency department (ED) visits (moderate certainty evidence). Exposure to heavy traffic may increase HA and deteriorate asthma control (low certainty evidence). Interventions reducing outdoor pollutants may reduce asthma exacerbations (low to very low certainty evidence). Exposure to fumigants may increase the risk of new-onset asthma in agricultural workers, while exposure to 1,3-dichloropropene may increase the risk of asthma-related ED visits (low certainty evidence). Heatwaves and cold spells may increase the risk of asthma-related ED visits and HA and asthma mortality (low certainty evidence).

Short-term exposure to air pollution on peripheral white blood cells and inflammation biomarkers: a cross-sectional study on rural residents

Effects of short-term exposure to ambient air pollution on systemic immunological and inflammatory biomarkers in rural population have not been adequately characterized. From May to July 2021, 5816 participants in rural villages of northern Henan Province, China, participated in this cross-sectional study. Blood biomarkers of systemic inflammation were determined including peripheral white blood cells (WBC), eosinophils (EOS), basophils (BAS), monocytes (MON), lymphocytes (LYM), neutrophils (NEU), neutrophil-lymphocyte ratio (NLR), and serum high-sensitivity C-reactive protein (hs-CRP). The concentrations of ambient fine particulate matter (PM2.5), PM10, nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) were assessed up to 7 days prior to the blood draw. A generalized linear model was used to analyze the associations between air pollution exposure and the above-mentioned blood biomarkers. Significantly positive associations were revealed between PM2.5, CO and WBC; CO, O3 and LYM; PM2.5, PM10, SO2, CO and NEU; PM2.5, PM10, SO2, CO and NLR; PM2.5, PM10, SO2, NO2, CO, O3 and hs-CRP. Meanwhile, negative associations were found between SO2 and WBC; PM2.5, PM10, NO2, CO, or O3 and EOS; PM2.5, SO2, or CO and BAS; SO2, NO2 or O3 and MON; PM2.5, PM10, SO2, or NO2 and LYM. Moreover, men, individuals with normal body mass index (BMI), current smokers, and those older than 60 years were found vulnerable to air pollution effects. Taken together, short-term exposure to air pollution was associated with systemic inflammatory responses, providing insight into the potential mechanisms for air pollution-induced detrimental systemic effects in rural residents.

Health-related quality of life 1 year after a large-scale industrial fire among exposed inhabitants of Rouen, France: 'The Post Fire 76 Health' study

BACKGROUND

A large-scale industrial fire occurred in Rouen, France, in 2019. This study assessed the health-related quality of life of people exposed to its consequences 1 year later.

METHODS

The study population comprised inhabitants of the exposed area and a non-exposed area. A representative sample was randomly selected using a stratified design. Data were collected using a standardized questionnaire to describe fire exposure and to calculate three health-related quality of life scores according to the SF12-v2 scale. After adjustment, descriptive and multivariate analyses were conducted.

RESULTS

The sample comprised 4773 participants (response rate 47.7%). In the exposed area, the average mental, physical and overall health scores were 47.5, 52.0 and 73.8 out of 100, respectively. Mean mental and overall health scores were higher in the non-exposed area (49.0 and 76.0, respectively). After adjustment, a lower mental health score was associated with a higher number of perceived types of exposure, reaching -3.72 points [-5.41; -2.04] for five or more different types of perceived exposure. A lower mental health score was associated with soot deposits (-1.04 [-1.70; -0.39]), perceiving odours [(-2.04 [-3.22; -0.86]) up to the day of data collection], and having seen, heard or been awakened by the fire (-1.21 [-1.90; -0.52]). A slightly lower physical health score was associated with soot deposits (-0.57 [-1.07; -0.08]).

CONCLUSION

This study highlighted associations between exposure to the consequences of the industrial fire in Rouen and a deterioration of perceived health-related quality of life 1 year later, particularly the mental health dimension.

A Roadmap for Using Causal Inference and Machine Learning to Personalize Asthma Medication Selection

Inhaled corticosteroid (ICS) is a mainstay treatment for controlling asthma and preventing exacerbations in patients with persistent asthma. Many types of ICS drugs are used, either alone or in combination with other controller medications. Despite the widespread use of ICSs, asthma control remains suboptimal in many people with asthma. Suboptimal control leads to recurrent exacerbations, causes frequent ER visits and inpatient stays, and is due to multiple factors. One such factor is the inappropriate ICS choice for the patient. While many interventions targeting other factors exist, less attention is given to inappropriate ICS choice. Asthma is a heterogeneous disease with variable underlying inflammations and biomarkers. Up to 50% of people with asthma exhibit some degree of resistance or insensitivity to certain ICSs due to genetic variations in ICS metabolizing enzymes, leading to variable responses to ICSs. Yet, ICS choice, especially in the primary care setting, is often not tailored to the patient's characteristics. Instead, ICS choice is largely by trial and error and often dictated by insurance reimbursement, organizational prescribing policies, or cost, leading to a one-size-fits-all approach with many patients not achieving optimal control. There is a pressing need for a decision support tool that can predict an effective ICS at the point of care and guide providers to select the ICS that will most likely and quickly ease patient symptoms and improve asthma control. To date, no such tool exists. Predicting which patient will respond well to which ICS is the first step toward developing such a tool. However, no study has predicted ICS response, forming a gap. While the biologic heterogeneity of asthma is vast, few, if any, biomarkers and genotypes can be used to systematically profile all patients with asthma and predict ICS response. As endotyping or genotyping all patients is infeasible, readily available electronic health record data collected during clinical care offer a low-cost, reliable, and more holistic way to profile all patients. In this paper, we point out the need for developing a decision support tool to guide ICS selection and the gap in fulfilling the need. Then we outline an approach to close this gap via creating a machine learning model and applying causal inference to predict a patient's ICS response in the next year based on the patient's characteristics. The model uses electronic health record data to characterize all patients and extract patterns that could mirror endotype or genotype. This paper supplies a roadmap for future research, with the eventual goal of shifting asthma care from one-size-fits-all to personalized care, improve outcomes, and save health care resources.

Inconsequential role for chemerin-like receptor 1 in the manifestation of ozone-induced lung pathophysiology in male mice

We executed this study to determine if chemerin-like receptor 1 (CMKLR1), a Gi/o protein-coupled receptor expressed by leukocytes and non-leukocytes, contributes to the development of phenotypic features of non-atopic asthma, including airway hyperresponsiveness (AHR) to acetyl-β-methylcholine chloride, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Accordingly, we quantified sequelae of non-atopic asthma in wild-type mice and mice incapable of expressing CMKLR1 (CMKLR1-deficient mice) following cessation of acute inhalation exposure to either filtered room air (air) or ozone (O3), a criteria pollutant and non-atopic asthma stimulus. Following exposure to air, lung elastic recoil and airway responsiveness were greater while the quantity of adiponectin, a multi-functional adipocytokine, in bronchoalveolar lavage (BAL) fluid was lower in CMKLR1-deficient as compared to wild-type mice. Regardless of genotype, exposure to O3 caused AHR, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Nevertheless, except for minimal genotype-related effects on lung hyperpermeability and BAL adiponectin, we observed no other genotype-related differences following O3 exposure. In summary, we demonstrate that CMKLR1 limits the severity of innate airway responsiveness and lung elastic recoil but has a nominal effect on lung pathophysiology induced by acute exposure to O3.

Mixed Metal Components in PM2.5 Contribute to Chemokine Receptor CCR5-Mediated Neuroinflammation and Neuropathological Changes in the Mouse Olfactory Bulb

Particulate matter, especially PM2.5, can invade the central nervous system (CNS) via the olfactory pathway to induce neurotoxicity. The olfactory bulb (OB) is the key component integrating immunoprotection and olfaction processing and is necessarily involved in the relevant CNS health outcomes. Here we show that a microglial chemokine receptor, CCR5, is the target of environmentally relevant PM2.5 in the OB to trigger neuroinflammation and then neuropathological injuries. Mechanistically, PM2.5-induced CCR5 upregulation results in the pro-inflammatory paradigm of microglial activation, which subsequently activates TLR4-NF-κB neuroinflammation signaling and induces neuropathological changes that are closely related to neurodegenerative disorders (e.g., Aβ deposition and disruption of the blood-brain barrier). We specifically highlight that manganese and lead in PM2.5 are the main contributors to CCR5-mediated microglial activation and neuroinflammation in synergy with aluminum. Our results uncover a possible pathway of PM2.5-induced neuroinflammation and identify the principal neurotoxic components, which can provide new insight into efficiently diminishing the adverse health effects of PM2.5.

Association of Long-Term Exposure to Ambient Air Pollution With the Risk of Acute Primary Angle Closure

Purpose

The purpose of this study was to investigate the association between long-term exposure to ambient air pollutants and the risk of acute primary angle closure (APAC).

Methods

Two hundred eighty-one (281) patients with APAC and 730 age- and sex-matched controls hospitalized between January 2017 and December 2019 were enrolled in this retrospective case-control study. Residential exposure to ambient air pollutants, including fine particulate matter (PM2.5), inhalable particulate (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone were estimated by satellite-models or ground measurement. Multivariate regression analyses explored the association between annual air pollutants exposure and the risk of APAC.

Results

Of the 1011 participants (31.1% were male subjects), the average age was 64.0 years. Long-term exposure to PM2.5, PM10, and SO2 were significantly associated with an increased risk of APAC. The adjusted odds ratios (aORs) for each interquartile range (IQR) increment of PM2.5, PM10, and SO2 were 1.28 (95% confidence interval [CI] = 1.06-1.57), 1.26 (95% CI = 1.06-1.50), and 1.30 (95% CI = 1.04-1.62) separately, after controlling for confounders. Robust associations were observed for a longer lag 2-year exposure.

Conclusions

Long-term exposure to PM2.5, PM10, and SO2 was associated with an increased risk of APAC in a Chinese population. Our findings provide epidemiological implications on the adverse effects of air pollution on ocular diseases.

Translational Relevance

Long-term exposure to ambient air pollutants increased the risk of APAC.

PM10 increases mortality risk in rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

The effect of air pollution on the prognosis of rheumatoid arthritis-associated interstitial lung disease (RA-ILD) remains poorly understood. We aimed to evaluate the effect of long-term exposure to particulate matter with an aerodynamic diameter of ≤10 µm (PM10) and nitrogen dioxide (NO2) on mortality in patients with RA-ILD.

METHODS

We included 309 patients (mean age, 61.7 years; male, 44.3%) with RA-ILD. Individual-level long-term exposures to PM10 and NO2 at their residential addresses were estimated using a national-scale exposure prediction model. The effect of the two air pollutants on mortality was estimated using a Cox-proportional hazards model adjusted for individual-level and area-level characteristics.

RESULTS

The median follow-up period was 4.8 years, and 40.8% of patients died or underwent lung transplantation. The annual average concentrations of PM10 and NO2 were 56.3 μg/m3 and 22.4 ppb, respectively. When air pollutant levels were stratified by quartiles, no association was observed between air pollutant concentration and mortality in patients with RA-ILD. However, when stratified by two groups (high exposure (top 25th percentile) vs low exposure (bottom 75th percentile)), we observed a significant association between high PM10 exposure and mortality (HR 1.68; 95% CI 1.11 to 2.52; p=0.013) but no association between NO2 exposure and mortality. In the subgroup analyses, the effect of high PM10 exposure on mortality was significant in patients aged <65 years (HR 1.98; 95% CI 1.02 to 3.85; p=0.045).

CONCLUSIONS

Our results indicated that high PM10 exposure may be associated with mortality in patients with RA-ILD.

Association Between Nitrogen Dioxide Pollution and Cause-Specific Mortality in China: Cross-Sectional Time Series Study

BACKGROUND

Nitrogen dioxide (NO2) has been frequently linked to a range of diseases and associated with high rates of mortality and morbidity worldwide. However, there is limited evidence regarding the risk of NO2 on a spectrum of causes of mortality. Moreover, adjustment for potential confounders in NO2 analysis has been insufficient, and the spatial resolution of exposure assessment has been limited.

OBJECTIVE

This study aimed to quantitatively assess the relationship between short-term NO2 exposure and death from a range of causes by adjusting for potential confounders in Guangzhou, China, and determine the modifying effect of gender and age.

METHODS

A time series study was conducted on 413,703 deaths that occurred in Guangzhou during the period of 2010 to 2018. The causes of death were classified into 10 categories and 26 subcategories. We utilized a generalized additive model with quasi-Poisson regression analysis using a natural cubic splines function with lag structure of 0 to 4 days to estimate the potential lag effect of NO2 on cause-specific mortality. We estimated the percentage change in cause-specific mortality rates per 10 μg/m3 increase in NO2 levels. We stratified meteorological factors such as temperature, humidity, wind speed, and air pressure into high and low levels with the median as the critical value and analyzed the effects of NO2 on various death-causing diseases at those high and low levels. To further identify potentially vulnerable subpopulations, we analyzed groups stratified by gender and age.

RESULTS

A significant association existed between NO2 exposure and deaths from multiple causes. Each 10 μg/m3 increment in NO2 density at a lag of 0 to 4 days increased the risks of all-cause mortality by 1.73% (95% CI 1.36%-2.09%) and mortality due to nonaccidental causes, cardiovascular disease, respiratory disease, endocrine disease, and neoplasms by 1.75% (95% CI 1.38%-2.12%), 2.06% (95% CI 1.54%-2.59%), 2.32% (95% CI 1.51%-3.13%), 2.40% (95% CI 0.84%-3.98%), and 1.18% (95% CI 0.59%-1.78%), respectively. Among the 26 subcategories, mortality risk was associated with 16, including intentional self-harm, hypertensive disease, and ischemic stroke disease. Relatively higher effect estimates of NO2 on mortality existed for low levels of temperature, relative humidity, wind speed, and air pressure than with high levels, except a relatively higher effect estimate was present for endocrine disease at a high air pressure level. Most of the differences between subgroups were not statistically significant. The effect estimates for NO2 were similar by gender. There were significant differences between the age groups for mortality due to all causes, nonaccidental causes, and cardiovascular disease.

CONCLUSIONS

Short-term NO2 exposure may increase the risk of mortality due to a spectrum of causes, especially in potentially vulnerable populations. These findings may be important for predicting and modifying guidelines for NO2 exposure in China.

Extreme temperature events and dementia mortality in Chinese adults: a population-based, case-crossover study

BACKGROUND

The effect of exposure to extreme temperature events (ETEs) on dementia mortality remains largely unknown. We aimed to quantify the association of ETE exposure with dementia mortality.

METHODS

We conducted a population-based, case-crossover study among 57 791 dementia deaths in Jiangsu province, China, during 2015-20. Daily mean temperatures were extracted from a validated grid dataset at each subject's residential address, and grid-specific exposures to heat wave and cold spell were assessed with a combination of their intensity and duration. We applied conditional logistic regression models to investigate cumulative and lag effects for ETE exposures.

RESULTS

Exposure to ETE with each of all 24 definitions was associated with an increased odds of dementia mortality, which was higher when exposed to heat wave. Exposure to heat wave (daily mean temperature ≥95th percentile, duration ≥3 days (d); P95_3d) and cold spell (≤5th percentile, duration ≥3 d; P5_3d) was associated with a 75% (95% CI: 61%, 90%) and 30% (19%, 43%) increase in odds of dementia mortality, respectively. Definitions with higher intensity were generally associated with a higher odds of dementia mortality. We estimated that 6.14% of dementia deaths were attributable to exposure to heat wave (P90_2d) and cold spell (P10_2d). No effect modifications were observed by sex or age, except that the association for heat wave was stronger among women.

CONCLUSIONS

Exposure to both heat wave and cold spell was associated with an increased odds of dementia mortality. Our findings highlight that reducing individual ETE exposures may be helpful in preventing deaths from dementia, especially among women in summer.

Short-term effects of air pollutants on hospital admissions for asthma among older adults: a multi-city time series study in Southwest, China

Background

This study aimed to explore the relationship between air pollution and hospital admissions for asthma in older adults, and to further assess the health and economic burden of asthma admissions attributable to air pollution.

Methods

We collected information on asthma cases in people over 65 years of age from nine cities in Sichuan province, as well as air pollution and meteorological data. The relationship between short-term air pollutant exposure and daily asthma hospitalizations was analyzed using the generalized additive model (GAM), and stratified by gender, age, and season. In addition, we assessed the economic burden of hospitalization for air pollution-related asthma in older adults using the cost of disease approach.

Results

The single pollutant model showed that every 1 mg/m3 increase in CO was linked with an increase in daily hospitalizations for older adults with asthma, with relative risk values of 1.327 (95% CI: 1.116-1.577) at lag7. Each 10 μg/m3 increase in NO2, O3, PM10, PM2.5 and SO2, on asthma hospitalization, with relative risk values of 1.044 (95% CI: 1.011-1.078), 1.018 (95% CI: 1.002-1.034), 1.013 (95% CI: 1.004-1.022), 1.015 (95% CI: 1.003-1.028) and 1.13 (95% CI: 1.041-1.227), respectively. Stratified analysis shows that stronger associations between air pollution and asthma HAs among older adult in females, those aged 65-69 years, and in the warm season, although all of the differences between subgroups did not reach statistical significance. During the study period, the number of asthma hospitalizations attributable to PM2.5, PM10, and NO2 pollution was 764, 581 and 95, respectively, which resulted in a total economic cost of 6.222 million CNY, 4.73 million CNY and 0.776 million CNY, respectively.

Conclusion

This study suggests that short-term exposure to air pollutants is positively associated with an increase in numbers of asthma of people over 65 years of age in Sichuan province, and short-term exposure to excessive PM and NO2 brings health and economic burden to individuals and society.

Effect of ambient air pollution on hospital admission for respiratory diseases in Hanoi children during 2007-2019

Air pollution poses a threat to children's respiratory health. This study aims to quantify the association between short-term air pollution exposure and respiratory hospital admissions among children in Hanoi, Vietnam, and estimate the population-attributable burden using local data. A case-crossover analysis was conducted based on the individual records where each case is their own control. The health data was obtained from 13 hospitals in Hanoi and air pollution data was collected from four monitoring stations from 2007 to 2019. We used conditional logistic regression to estimate Percentage Change (PC) and 95% Confidence Interval (CI) in odd of hospital admissions per 10 μg/m3 increase in daily average particulate matter (e.g. PM1, PM2.5, PM10), Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), 8-h maximum Ozone and per 1000 μg/m3 increase in daily mean of Carbon Monoxide (CO). We also calculated the number and fraction of admissions attributed to air pollution in Hanoi by using the coefficient at lag 0. A 10 μg/m3 increase in the concentration of PM10, PM2.5, PM1, SO2, NO2, O3 8-h maximum and 1000 μg/m3 increase in CO concentration was associated with 0.6%, 1.2%, 1.4%, 0.8%, 1.6%, 0.3%, and 1.7% increase in odd of admission for all respiratory diseases among children under 16 years at lag 0-2. All PM metrics and NO2 are associated with childhood admission for pneumonia and bronchitis. Admissions due to asthma and upper respiratory diseases are related to increments in NO2 and CO. For attributable cases, PM2.5 concentrations in Hanoi exceeding the World Health Organization Air Quality Guidelines accounted for 1619 respiratory hospital admissions in Hanoi children in 2019. Our findings show that air pollution has a detrimental impact on the respiratory health of Hanoi children and there will be important health benefits from improved air quality management planning to reduce air pollution in Vietnam.

Ozone, Heat Wave, and Cardiovascular Disease Mortality: A Population-Based Case-Crossover Study

A case-crossover study among 511,767 cardiovascular disease (CVD) deaths in Jiangsu province, China, during 2015-2021 was conducted to assess the association of exposure to ambient ozone (O3) and heat wave with CVD mortality and explore their possible interactions. Heat wave was defined as extreme high temperature for at least two consecutive days. Grid-level heat waves were defined by multiple combinations of apparent temperature thresholds and durations. Residential O3 and heat wave exposures were assessed using grid data sets (spatial resolution: 1 km × 1 km for O3; 0.0625° × 0.0625° for heat wave). Conditional logistic regression models were applied for exposure-response analyses and evaluation of additive interactions. Under different heat wave definitions, the odds ratios (ORs) of CVD mortality associated with medium-level and high-level O3 exposures ranged from 1.029 to 1.107 compared with low-level O3, while the ORs for heat wave exposure ranged from 1.14 to 1.65. Significant synergistic effects on CVD mortality were observed for the O3 and heat wave exposures, which were generally greater with higher levels of the O3 exposure, higher temperature thresholds, and longer durations of heat wave exposure. Up to 5.8% of the CVD deaths were attributable to O3 and heat wave. Women and older adults were more vulnerable to the exposure to O3 and heat wave exposure. Exposure to both O3 and heat wave was significantly associated with an increased odds of CVD mortality, and O3 and heat wave can interact synergistically to trigger CVD deaths.

The impact of air pollution on asthma: clinical outcomes, current epidemiology, and health disparities

INTRODUCTION

Air pollution has been shown to have a significant impact on morbidity and mortality of respiratory illnesses including asthma.

AREAS COVERED

Outdoor air pollution consists of a mixture of individual pollutants including vehicle traffic and industrial pollution. Studies have implicated an array of individual components of air pollution, with PM2.5, NO2, SO2, and ozone being the most classically described, and newer literature implicating other pollutants such as black carbon and volatile organic compounds. Epidemiological and cohort studies have described incidence and prevalence of pollution-related asthma and investigated both acute and chronic air pollution exposure as they relate to asthma outcomes. There is an increasing body of literature tying disparities in pollution exposure to clinical outcomes. In this narrative review, we assessed the published research investigating the association of pollution with asthma outcomes, focusing on the adult population and health care disparities.

EXPERT OPINION

Pollution has multiple deleterious effects on respiratory health but there is a lack of data on individualized pollution monitoring, making it difficult to establish a temporal relationship between exposure and symptoms, thereby limiting our understanding of safe exposure levels. Future research should focus on more personalized monitoring and treatment plans for mitigating exposure.

Role of antenatal anxiety in the relationship between maternal exposure to nitrogen dioxide and small for gestational age: A birth cohort study

BACKGROUND

Both Nitrogen dioxide (NO2) exposure and antenatal anxiety have individually been associated with small for gestational age (SGA). Little is known, however, about whether there is effect modification of antenatal anxiety on NO2-related SGA.

METHODS

The prospective birth cohort study included 1823 mother-newborn pairs in Guangzhou, China, from January 2017 to April 2020. Exposure to NO2 during the pre-conceptional and prenatal periods was estimated using an inverse distance weighted method. Antenatal anxiety was assessed by Trait Anxiety Inventory. SGA was determined by the Chinese gestational age- and sex-specific birthweight standards. Cox proportional hazards regression models was used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for SGA as per 10 μg/m3 increase in NO2. Modifying effects of trait anxiety on NO2-related SGA were identified by stratified analyses, and three-dimensional response surface plots and two-dimensional heat maps.

RESULTS

Each 10 μg/m3 increase in NO2 exposure during the third trimester was significantly associated with SGA risk among overall participants (HR = 1.221, 95 % CI: 1.014-1.471) and primipara (HR = 1.271, 95 % CI: 1.023-1.579). We found significant effect modification of anxiety level for NO2-related SGA in the third trimester (Pinteraction < 0.05). Pregnant women with higher levels of trait anxiety were more likely to deliver SGA newborns, particularly for those with high trait anxiety (HR = 1.781, 95 % CI: 1.007-2.945). Primiparous women were more susceptible.

CONCLUSIONS

This study provides evidence that antenatal trait anxiety may modify the effects of maternal NO2 exposure on SGA risk. The third trimester could be a critical window of susceptibility.

Short-term ambient ozone exposure increases the risk of hospitalization with depression: a multi-city time-stratified case-crossover study

BACKGROUND

Depression, the most common mental illness worldwide, has been studied and air pollution has been found to increase the risk of depression hospitalization, but research results on ozone (O3) remain limited. In this context, we investigated the relationship between short-term O3 exposure and depression-related hospital admissions (HAs).

METHODS

The 10,459 records of HAs for depression from medical institutions across in 9 cities, China, were collected between 1 January 2017, and 31 December 2018. Air pollutants and meteorological data was obtained from provincial ecological environment monitoring stations in the study area. Conditional Poisson regression was employed to estimate the association between O3 and hospitalizations for depression, with data stratification by sex, age, weather, and economic level.

RESULTS

Short-term O3 exposure was positively associated with the number of depression-related hospitalizations (Relative risk: 1.04 [95% CI: 1.02, 1.05]). O3 had a significant effect on the risk of depression-related hospitalizations on warm days (P = 0.021, Relative risk: 1.05 [1.03, 1.08]). The high gross domestic product group was more likely to be affected by O3 exposure-associated depression-related hospitalizations (P = 0.005, Relative risk: 1.03 [1.01, 1.05]).

CONCLUSIONS

Short-term changes to O3 exposure may increase the risk of depression related hospitalizations, especially on warm days.

Integrative proteomics and metabolomics analysis of non-observable acute effect level PM2.5 induced accumulative effects in AC16 cells

Chronic exposure to very low ambient PM2.5 has been linked to cardiovascular risks in epidemiological observation, which also brought doubts on its safety threshold. In this study, we approached this question by chronic exposure of AC16 to the non-observable acute effect level (NOAEL) PM2.5 5 μg/mL and its positive reference 50 μg/mL, respectively. The doses were respectively defined on the cell viabilities >95% (p = 0.354) and >90% (p = 0.004) when treated acutely (24 h). To mimic the long-term exposure, AC16 was cultured from the 1st to 30th generations and treated with PM2.5 24 h in every three generations. The integration of proteomic and metabolomic analysis was applied, and 212 proteins and 172 metabolites were significantly altered during the experiments. The NOAEL PM2.5 induced both dose- and time-dependent disruption, which showed the dynamic cellular proteomic response and oxidation accumulation, the main metabolomics changes were ribonucleotide, amino acid, and lipid metabolism that have involved in stressed gene expression, and starving for energy metabolism and lipid oxidation. In summary, these pathways interacted with the monotonically increasing oxidative stress and led to the accumulated damage in AC16 and implied that the safe threshold of PM2.5 may be non-existent when a long-term exposure occurred.

Age at menarche and asthma onset among US girls and women: findings from NHANES, 2001-2018

PURPOSE

To quantitatively estimate the association of age at menarche with the risk of childhood- and adult-onset asthma separately.

METHODS

A retrospective cohort study of 24,282 US girls and women was conducted using continuous National Health and Nutrition Examination Survey (NHANES) data from 2001 to 2018, and Cox proportional hazards regression models with censoring ages of 19 and 79 years were employed to separately estimate hazard ratios of childhood- and adult-onset asthma associated with age at menarche.

RESULTS

Each one-year increase in age at menarche was significantly associated with a 16% (hazard ratio [HR] = 0.84; 95% confidence interval [CI]: 0.77-0.91) decrease in the risk of childhood-onset asthma. Compared with age at menarche of 12-14 years, we observed a 56% (HR = 1.56; 95% CI: 1.19-2.04) increased risk of childhood-onset asthma for early menarche (age at menarche < 12 years) and a 40% (HR = 0.60; 95% CI: 0.32-1.10) decreased risk for late menarche (age at menarche ≥ 15 years). No significant association was noted between age at menarche and adult-onset asthma.

CONCLUSIONS

Early menarche may represent a risk factor for childhood-onset asthma, which indicates the need for timely and effective management of individuals with early menarche to prevent asthma.

Cumulative and lagged effects of varying-sized particulate matter exposure associates with toddlers' gut microbiota

Particulate matter (PM) is an important component of air pollutants and is associated with various health risks. However, the impact of PM on toddlers' gut microbiota is rarely investigated. This study aimed to assess the cumulative and lagged effects of varying-sized PMs on toddlers' gut microbiota. We collected demographic information, stool samples, and exposure to PM from 36 toddlers aged 2-3 years. The toddlers were divided into warm season group and cooler season group according to the collection time of stool samples. The gut microbiota was processed and analyzed using 16S rRNA V3-V4 gene regions. The concentration of PM was calculated using China High Air Pollutants (CHAP) database. To assess the mixed effects of varying-sized PM, multiple-PM models were utilized. There were significant differences between the community composition, α- and β-diversity between two groups. In multiple-PM models, there was a significant effect of weight quantile sum (PM1, PM2.5, and PM10) on α-diversity indices. In weight quantile sum models, after adjusting for a priori confounders, we found a negative effect of weight quantile sum on Enterococcus (β = -0.134, 95% CI -0.263 to -0.006), positive effects of weight quantile sum on unclassified_f__Ruminococcaceae (β = 0.247, 95% CI 0.102 to 0.393), Ruminococcus_1 (β = 0.444, 95% CI 0.238 to 0.650), unclassified_f__Lachnospiraceae (β = 0.278, 95% CI 0.099 to 0.458), and Family_XIII_AD_3011_group (β = 0.254, 95% CI 0.086 to 0.422) in WSG and CSG. In lagged weight quantile sum models, the correlation between lag time PM levels and the gut microbiota showed seasonal trends, and weights of PM changed with lag periods. This is the first study to highlight that cumulative and lagged effects of PMs synergistically affect the diversities (α- and β-diversity) and abundance of the gut microbiota in toddlers. Further research is needed to explore the mediating mechanism of varying-sized PMs exposure on the gut microbiota in toddlers.

Effect of altered human exposome on the skin and mucosal epithelial barrier integrity

Pollution in the world and exposure of humans and nature to toxic substances is continuously worsening at a rapid pace. In the last 60 years, human and domestic animal health has been challenged by continuous exposure to toxic substances and pollutants because of uncontrolled growth, modernization, and industrialization. More than 350,000 new chemicals have been introduced to our lives, mostly without any reasonable control of their health effects and toxicity. A plethora of studies show exposure to these harmful substances during this period with their implications on the skin and mucosal epithelial barrier and increasing prevalence of allergic and autoimmune diseases in the context of the "epithelial barrier hypothesis". Exposure to these substances causes an epithelial injury with peri-epithelial inflammation, microbial dysbiosis and bacterial translocation to sub-epithelial areas, and immune response to dysbiotic bacteria. Here, we provide scientific evidence on the altered human exposome and its impact on epithelial barriers.

Fine and coarse particulate air pollution and out-of-hospital cardiac arrest onset: a nationwide case-crossover study in China

Out-of-hospital cardiac arrest (OHCA) is a global public health concern. Nationwide studies on the effects of short-term exposure to particulate matter (PM) on OHCA risk are rare in regions with high PM levels, and evidence for coarse PM (PM_2.5-10) is limited and inconsistent. To evaluate the associations between fine PM (PM_2.5) and PM_2.5-10 and OHCA onset, a time-stratified case-crossover study was conducted on 77,261 patients with cardiac OHCA in 26 cities across China in 2020. Daily PM_2.5 and PM_2.5-10 concentrations were assessed with high-resolution and full-coverage PM estimations. Conditional logistic regression models were applied in analyses. Each interquartile range of PM increase in 3-day moving average was associated with an increased risk of cardiac OHCA onset of 2.37% (95% CI, 1.20-3.56%) for PM_2.5 and 2.12% (95% CI, 0.70-3.56%) for PM_2.5-10. Stratified analyses showed higher susceptibility in patients over 75 years for PM_2.5 exposure and with diabetes for PM_2.5-10. This first nationwide study in region with high PM levels and great PM variability found not only PM_2.5 but also PM_2.5-10 were associated with a higher risk of OHCA onset, which could add powerful epidemiological evidence to this field and provide new evidence for the formulation of air quality guidelines.

Short-term effects of ambient ozone exposure on daily hospitalizations for circulatory diseases in Ganzhou, China: A time-series study

Adverse health effects of ambient ozone are getting widespread attention, but the evidence on the relationship between ozone levels and circulatory system diseases are limited and inconsistent. Daily data for ambient ozone levels and hospitalizations for total circulatory diseases and five subtypes in Ganzhou, China from January 1, 2016 to December 31, 2020 were collected. We constructed a generalized additive model with quasi-Poisson regression accounting for lag effects to estimate the associations between ambient ozone levels and the number of hospitalized cases of total circulatory diseases and five subtypes. The differences among gender, age, and season subgroups were furtherly assessed through stratified analysis. A total of 201,799 hospitalized cases of total circulatory diseases were included in the present study, including 94,844 hypertension (HBP), 28,597 coronary heart disease (CHD), 42,120 cerebrovascular disease (CEVD), 21,636 heart failure (HF), and 14,602 arrhythmia. Significantly positive associations were observed between ambient ozone levels and daily hospitalizations for total circulatory diseases and all subtypes except arrhythmia. Each 10 μg/m³ increase in ozone concentration, the risk of hospitalizations for total circulatory diseases, HBP, CHD, CEVD, and HF increased by 0.718% (95% confidence interval, 0.156%-1.284%), 0.956% (0.346%-1.570%), 0.499% (0.057%-0.943%), 0.386% (0.025%-0.748%), and 0.907% (0.118%-1.702%), respectively. The above associations remained significant after adjusting for other air pollutants. The risk of hospitalization for circulatory diseases was higher in warm season (May to October) and varied in gender and age subgroups. This study suggested that short-term exposure to ambient ozone may increase the risk of hospitalizations for circulatory diseases. Our findings reinforce the importance of reducing ambient ozone pollution levels for protecting public health.

Influence of different concentrations of ozone on the alteration of mitochondrial DNA copy numbers in human peripheral blood

By now, O₃ pollution has become a main environmental problem. O₃ is a prevalent risk factor for many diseases, but the regulatory factors linking O₃ and diseases remain ambiguous. Mitochondrial DNA (mtDNA) is the genetic material in mitochondria, which plays a key role in the production of respiratory ATP. Due to a lack of histone protection, mtDNA is easily damaged by ROS, and O₃ is an important source to stimulate the production of endogenous ROS in vivo. Therefore, we logically speculate that O₃ exposure can alter mtDNA copy number by the induction of ROS. In the present study, we performed a panel study of 65 MSc students at the Chinese research academy of environmental sciences (CRAES) with 3 rounds of follow-up visits from August 2021 to January 2022. We examined the mtDNA copy numbers in the peripheral blood of subjects using quantitative polymerase chain reaction. Linear mixed-effect (LME) model and stratified analysis were used to investigate the association between O₃ exposure and mtDNA copy numbers. We found a dynamic process of the association between the concentration of O₃ exposure and the mtDNA copy number in the peripheral blood. The lower concentration of O₃ exposure did not affect the mtDNA copy number. As the concentration of O₃ exposure increased, the mtDNA copy number also increased. While, when O₃ exposure reached a certain concentration, a decrease in mtDNA copy number was found. This correlation between the concentration of O₃ and the mtDNA copy number could be ascribed to the severity of cellular damage induced by O₃ exposure. Our results provide a new perspective for the discovery of a biomarker of O₃ exposure and health response, as well as for the prevention and treatment of adverse health effects caused by different concentrations of O₃.

Ambient ozone exposure and depression among middle-aged and older adults: Nationwide longitudinal evidence in China

BACKGROUND

Epidemiological studies have linked long-term ozone (O₃) exposure with depression in developed countries. However, available literature is sparse and exists great heterogeneities. We aimed to investigate the association of long-term O₃ exposure with depression among Chinese middle-aged and older adults.

METHODS

We designed a repeated measurement study based on longitudinal data from four waves (2011, 2013, 2015, and 2018) of the China Health and Retirement Longitudinal Study (CHARLS). Annual mean O₃ concentrations assessed through machine learning-based spatiotemporal models were assigned to each participant at city level. Depression score was measured using the 10-item Center for Epidemiologic Studies Depression scale (CES-D-10), with scores above the cut-off point of ten defined as depressive symptom. Mixed-effects models were used to evaluate the impact of O₃ on depression score and depressive symptom, and quantify the concentration-response (C-R) relationships. Subgroup analyses were performed to examine the potential effect modifications.

RESULTS

A total of 19,582 participants with 60,125 visits were included in our analysis, with mean depression score of 8.1 (standard deviation: 6.3). Multivariable-adjusted mixed-effects model estimated a 6.34% (95% confidence interval [CI]: 3.34%, 9.43%) increase in depression score and an odds ratio (OR) of 1.29 (95% CI: 1.16, 1.45) for depressive symptom associated with per 10-μg/m³ rise in annual mean O₃ exposure. Significantly elevated risks were identified only at high concentrations (approximately ≥90 μg/m³). Participants who suffered from chronic diseases had a significant increased risk of depression (% Change in depression score: 8.42% [95% CI: 4.79%, 12.17%], and OR: 1.42 [95% CI: 1.24, 1.62]), and an evident effect modification was identified for depressive symptom (P = 0.01).

FINDINGS

Our study provided novel evidence that long-term O₃ exposure could be a risk factor for depression among Chinese middle-aged and older adults. Our findings may have significant implications for formulating policies in reducing disease burden of depression by controlling air pollution.

Formaldehyde exacerbates asthma in mice through the potentiation of HIF-1α-mediated pro-inflammatory responses in pulmonary macrophages

Exposure to formaldehyde (FA) has been indicated to be positively correlated with increased incidence of allergic asthma in many epidemiological and experimental studies. However, few studies have ever addressed the molecular basis of the correlation. In the present study, it was found that inhaling 2.0 mg/m³ FA for 2 weeks could exacerbate the pulmonary inflammation and mucus over-accumulation in OVA-induced murine asthmatic model. The pro-inflammatory cytokines, such as IL-1β, TNF-α, IL-6 and IL-8, were increased in lung and serum of FA-exposed asthmatic mice. The contribution of HIF-1α signaling in FA-exacerbated allergic asthma was confirmed by bioinformatic analysis. HIF-1α and its downstream proteins, which are known as mediators of glycolysis, were found to be upregulated by 50 μM FA, and the FA-enhanced of glycolysis was reversed by inhibition of HIF-1α with PX-478 in vitro and YC-1 in vivo. Furthermore, it was confirmed that inhibition of HIF-1α signaling could restrain the macrophagic inflammatory responses and asthma exacerbation induced by FA. Collectively, these results revealed that FA could exacerbate asthma through the potentiation of HIF-1α-mediated inflammatory responses in macrophages, which also indicated the universal roles of FA-triggered macrophage metabolic and functional alterations in inflammatory or allergic diseases.

Air pollution and stroke hospitalization in the Beibu Gulf Region of China: A case-crossover analysis

BACKGROUND

The relationship between air pollution and stroke has been extensively studied, however, the evidence regarding the association between air pollution and hospitalization due to stroke and its subtypes in coastal areas of China is limited.

OBJECTIVE

To estimate the associations between air pollution and hospitalizations of stroke and its subtypes in the Beibu Gulf Region of China.

METHODS

We conducted a time-stratified case-crossover study in 15 cities in Beibu Gulf Region in China from 2013 to 2016. Exposures to PM₁, PM_2.5, PM₁₀, SO₂, NO₂, O₃, and CO on the case and control days were assessed at residential addresses using bilinear interpolation. Conditional logistic regressions were constructed to estimate city-specific associations adjusting for meteorological factors and public holidays. Meta-analysis was further conducted to pool all city-level estimates.

RESULTS

There were 271,394 case days and 922,305 control days. The odds ratios (ORs) for stroke hospitalizations associated with each interquartile range (IQR) increase in 2-day averages of SO₂ (IQR: 10.8 µg/m³), NO₂ (IQR: 11.2 µg/m³), and PM₁₀ (IQR: 37 µg/m³) were 1.047 (95 % CI [confidence interval]: 1.015-1.080), 1.040 (95 % CI: 1.027-1.053), and 1.018 (95 % CI: 1.004-1.033), respectively. The associations with hospitalizations of ischemic stroke were significant for all seven pollutants, while the association with hemorrhagic stroke was significant only for CO. The associations of SO₂, NO₂, and O₃ with stroke hospitalization were significantly stronger in the cool season.

CONCLUSIONS

Short-term increase in SO₂, NO₂, and PM₁₀ might be important triggers of stroke hospitalization. All seven air pollutants were associated with ischemic stroke hospitalization, while only CO was associated with hemorrhagic stroke hospitalization. These results should be considered in public health policy.

Long-term exposure to PM2.5 and O3 with cardiometabolic multimorbidity: Evidence among Chinese elderly population from 462 cities

Cardiometabolic multimorbidity (CMM) refers to the presence of multiple cardiovascular and metabolic diseases (CMDs), such as hypertension, diabetes, and cardio-cerebrovascular diseases (CCVD), in the same individual, and has emerge as a significant global health concern due to population aging. Although previous research has demonstrated the association between cardiovascular and metabolic diseases and air pollutants, evidence on the link between CMM and air pollution exposure among Chinese older adults is limited. To address this research gap, we conducted a national representative survey of 222,179 adults aged 60 and older to investigate the epidemiology of CMM and its association with long-term exposure to PM_2.5 and O₃ in China's elderly population. We found that the prevalence of CMM among Chinese older adults was 16.9%, and hypertension and CCVD were the most common CMM cluster (10.8%). After adjusting for confounding variables, we observed a significant positive association between PM_2.5 exposure and the prevalence of hypertension, diabetes, and CCVD, with a respective excess risk increase of 3.2%, 3.6%, and 5.5% for every 10-unit increase. Moreover, every 10-unit increase in PM_2.5 was linked to a higher risk of hypertension and diabetes (2.2%), hypertension and CCVD (5.4%), diabetes and CCVD (5.6%), and hypertension, diabetes, and CCVD combined (7.6%). We also found a U-shaped curve relationship between O₃ exposure and the occurrence of hypertension, diabetes, and CCVD, as well as different subtypes of CMM, with the lowest risk of O₃ exposure was observed near 75-80 μg/m³. Furthermore, we identified that female and rural residents are more vulnerable to the health risks of air pollution than male and urban residents. Given the increasing aging of the population and rising prevalence of multimorbidity, policymakers should focus more attention on the female and rural elderly population to prevent and control CMM. This study provides compelling evidence that reducing air pollution levels can be an effective strategy to prevent and manage CMM among older adults.

Cold spells linked with respiratory disease hospitalization, length of hospital stay, and hospital expenses: Exploring cumulative and harvesting effects

BACKGROUND

Previous studies have revealed the relationship between cold spells and morbidity and mortality due to respiratory diseases, while the detrimental effects of cold spells on the length of hospital stay and hospitalization expenses remain largely unknown.

METHODS

We collected hospitalization data for respiratory diseases in 11 cities of Shanxi, China during 2017-2019. In each case, exposure to meteorological variables and air pollution was estimated by the bilinear interpolation approach and inverse distance weighting method, respectively, and then averaged at the city level. Cold spells were defined as the daily mean temperature below the 10^th, 7.5^th, or 5^th percentiles for at least 2 to 5 consecutive days. We applied distributed lag non-linear models combined with generalized additive models to assess cumulative effects and harvesting effects.

RESULTS

There were significant associations between cold spells and hospital admissions, length of hospital stay, and hospital expenses for respiratory diseases. Compared with the non-cold spell period, the overall (lag 0-21) cumulative risk of hospitalization for total respiratory diseases was 1.232 (95 % CI: 1.090, 1.394) on cold spell days, and the increased length of hospital stay and hospitalization expenses were 112.793 (95 % CI: 10.755, 214.830) days and 127.568 (95 % CI: 40.513, 214.624) thousand Chinese yuan. The overall cumulative risks of cold spells on total respiratory diseases and pneumonia were statistically significant. We further observed harvesting effects in the associations between cold spells and hospital admission, length of hospital stay, and hospitalization expenses for respiratory diseases.

CONCLUSIONS

Cumulative cold-spell exposure for up to three weeks is associated with hospitalization, length of hospital stay, and hospital expenses for respiratory diseases. The observed harmful effects of cold spells on respiratory diseases can be partly attributable to harvesting effects.

Association of ambient carbon monoxide exposure with hospitalization risk for respiratory diseases: A time series study in Ganzhou, China

Background

Ambient carbon monoxide (CO) exposure is associated with increased mortality and hospitalization risk for total respiratory diseases. However, evidence on the risk of hospitalization for specific respiratory diseases from ambient CO exposure is limited.

Methods

Data on daily hospitalizations for respiratory diseases, air pollutants, and meteorological factors from January 2016 to December 2020 were collected in Ganzhou, China. A generalized additive model with the quasi-Poisson link and lag structures was used to estimate the associations between ambient CO concentration and hospitalizations of total respiratory diseases, asthma, chronic obstructive pulmonary disease (COPD), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), and influenza-pneumonia. Possible confounding co-pollutants and effect modification by gender, age, and season were considered.

Results

A total of 72,430 hospitalized cases of respiratory diseases were recorded. Significant positive exposure-response relationships were observed between ambient CO exposure and hospitalization risk from respiratory diseases. For each 1 mg/m³ increase in CO concentration (lag0-2), hospitalizations for total respiratory diseases, asthma, COPD, LRTI, and influenza-pneumonia increased by 13.56 (95% CI: 6.76%, 20.79%), 17.74 (95% CI: 1.34%, 36.8%), 12.45 (95% CI: 2.91%, 22.87%), 41.25 (95% CI: 18.19%, 68.81%), and 13.5% (95% CI: 3.41%, 24.56%), respectively. In addition, the associations of ambient CO with hospitalizations for total respiratory diseases and influenza-pneumonia were stronger during the warm season, while women were more susceptible to ambient CO exposure-associated hospitalizations for asthma and LRTI (all P < 0.05).

Conclusion

In brief, significant positive exposure-response relationships were found between ambient CO exposure and hospitalization risk for total respiratory diseases, asthma, COPD, LRTI, and influenza-pneumonia. Effect modification by season and gender was found in ambient CO exposure-associated respiratory hospitalizations.