Short-Term Exposure to Ambient Air Pollution and Mortality From Myocardial Infarction

Association of short-term exposure to PM1 with hospital admission from total and cause-specific respiratory diseases

BACKGROUND AND OBJECTIVE

Evidence of short-term exposure to particulate matter with an aerodynamic diameter ≤1 μm (PM1) on hospital admission for respiratory diseases (RDs) is limited. We aimed to estimate the associated risk of PM1 on hospital admissions for RDs.

METHODS

In this time-stratified case-crossover study, we assigned cases who had been admitted to hospital for RDs in Guangdong, China between 2016 and 2019. Exposure to PM1 was assigned on the basis of the patient's residence for each case day and its control days. Conditional logistic regression models and distributed lag nonlinear models were used to quantify the association of PM1 exposure with hospital admission for RDs at lag 0-1 days.

RESULTS

A total of 408, 658 hospital admissions for total RDs were recorded in the study period. Each 10 μg/m3 increase in PM1 was significantly associated with a 1.39% (95% confidence interval [CI]: 0.87%-1.91%), 1.97% (95% CI: 1.06%-2.87%) and 1.69% (95% CI: 0.67%-2.71%) increase in odds of hospital admissions for total RDs, chronic obstructive pulmonary disease (COPD) and pneumonia. The excess fraction of hospital admission for total RDs attributable to PM1 exposure was 6.03%, while 6.59% for COPD and 7.48% for pneumonia. Besides, higher excess fractions were more pronounced for hospital admission of total RDs in older patients (>75 years).

CONCLUSION

Our results support that PM1 is associated with increased risks of hospital admissions for RDs. It emphasizes the needs to pay attention to the effects of PM1 on respiratory health, especially among elderly patients.

Associations between main ambient air pollutants and ischaemic heart disease risk in the UK biobank: A prospective cohort study

OBJECTIVES

Air pollutants have been associated with multiple cardiovascular diseases, but evidence on the long-term and combined effects of air pollutants on the incidence of ischaemic heart disease (IHD) remains limited.

STUDY DESIGN

Prospective cohort study.

METHODS

A total of 398,547 participants from the UK Biobank were included in this prospective cohort study. Concentrations of air pollutants were calculated using the Land Use Regression (LUR) model, including particulate matter (PM) [PM2.5, PM10-2.5, PM10] and nitrogen oxides (NOx and NO2). Cox proportional hazards models and restricted cubic spline models were utilised to detect associations between air pollutants and IHD incidence. A novel air pollution score was proposed to indicate the synergistic effect of five air pollutants by combining variance contribution and eigenvalue of each pollutant in principal components analysis (PCA).

RESULTS

In a median follow-up of 12.5 years, 23,721 of 398,547 participants were diagnosed with IHD. For every 1-μg/m3 increase, the risk of IHD was 1.026 (95 % confidence interval [CI]: 1.012-1.040) and 1.002 (95 % CI: 1.001-1.003) for PM2.5 and NOx, respectively. This study found that for every increase in quartile of PM2.5 level, the hazard ratios (HRs) for IHD were 1.035 (95 % CI: 0.998-1.073), 1.043 (95 % CI: 1.005-1.082) and 1. 063 (95 % CI: 1.022-1.106) compared with the lowest quartile. Long-term estimated exposure to multiple air pollutants showed a significant association with elevated risk of IHD (HRs = 1.029, 95 % CI: 1.007-1.051) and the exposure-response curve was linear.

CONCLUSIONS

Among UK adults, long-term and synchronous exposure to multiple air contaminants was associated with an increased risk of IHD.

Low ambient temperature and incident myocardial infarction with or without obstructive coronary arteries: a Chinese nationwide study

BACKGROUND AND AIMS

Although non-optimum ambient temperature is a major non-traditional risk factor for acute myocardial infarction, there is no prior knowledge on whether non-optimum ambient temperature could differentially affect myocardial infarction with obstructive coronary artery disease (MI-CAD) and myocardial infarction with non-obstructive coronary arteries (MINOCA).

METHODS

Using the Chinese Cardiovascular Association database-Chest Pain Center Registry, a nationwide, time-stratified, case-crossover investigation was conducted from 2015 to 2021. Meteorological data were obtained from an established satellite-based model, and daily exposures were assigned according to the onset of myocardial infarction in each patient. A conditional logistic regression model combined with distributed lag non-linear models (10 days) was used to estimate the exposure-response relationships.

RESULTS

A total of 83 784 MINOCA patients and 918 730 MI-CAD patients were included. The risk of MINOCA and MI-CAD associated with low temperature occurred at lag 2 day and lasted to 1 week. Extremely low temperature was associated with a substantially greater odds ratio (OR) of MINOCA [OR 1.58, 95% confidence interval (CI) 1.31-1.90] than MI-CAD (unmatched: OR 1.32, 95% CI 1.23-1.43; equally matched by age and sex: OR 1.25, 95% CI 1.04-1.50), compared with the corresponding reference temperatures (30°C, 35°C, and 30°C). Stronger associations were observed for patients who were aged ≥65 years, female, or resided in the south. There was no significant difference for the impacts of high temperature on MINOCA and MI-CAD.

CONCLUSIONS

This nationwide study highlights the particular susceptibility of MINOCA patients to ambient low temperature compared with that of MI-CAD patients.

The impact of air pollution on influenza incidence in high-altitude regions: a time-stratified case-crossover study based on Qinghai Province

BACKGROUND

The unique characteristics of air pollution in high-altitude regions may significantly influence the transmission and incidence of influenza. However, current research on this phenomenon is limited, and further investigation is urgently needed.

METHODS

This study collected influenza outpatient data from Qinghai Province between January 1, 2016, and December 31, 2021. We employed a time-stratified case-crossover design combined with conditional Poisson regression models to quantitatively analyze the relationship between air pollutants (PM2.5, SO2, NO2) and influenza incidence and explored the moderating role of temperature in this relationship. Additionally, stratified analyses were conducted to identify potential vulnerable populations.

RESULTS

The study results indicated that exposure to PM2.5, SO2, and NO2 was positively associated with the risk of influenza incidence. For every 10 µg/m³ increase in the concentration of PM2.5, SO2, and NO2, the percentage change in relative risk (RR) of influenza incidence was 0.35% (95% CI: 0.02%, 0.68%), 2.24% (95% CI: 1.42%, 3.06%), and 1.91% (95% CI: 1.16%, 2.67%), respectively. Under low-temperature conditions, the impact of pollutants other than O3 on influenza incidence was particularly pronounced. Children, the elderly, and individuals living at altitudes of 3000-3500 m were more sensitive to these pollutants.

CONCLUSION

This study revealed a close link between air pollution and influenza in high-altitude regions, with greater health risks under low-temperature conditions. The findings underscore the necessity of strengthening air quality monitoring and raising public awareness of environmental health.

Associations of Ozone Exposure with Serum Biomarkers in Acute Myocardial Infarction Patients in Taiyuan, China: The Mediating Role of Metabolites

Abundant epidemiological studies have conclusively demonstrated the effects of short-term ozone (O3) exposure on the incidence and mortality of cardiovascular diseases. However, the mechanism of its influence remains unverified. This study aimed to assess the impact of O3 on metabolomic-based biomarkers in acute myocardial infarction (AMI) patients. Accurate biomarkers for AMI were identified by combining serum biomarkers with metabolomics. A total of 137 volunteers were recruited, including 79 AMI patients and 58 healthy participants, from March to April 2023 in Taiyuan, China. Linear regression models were applied to analyze the associations of serum biomarkers and metabolites with O3. Mediation analyses were also conducted to assess the impact of metabolites, acting as mediators, on the associations between O3 and biomarkers. We found that O3 at lag2 captured the most remarkable effects. Metabolomic analysis revealed a substantial association between O3 (lag2) and 43 metabolites. Pathway analysis revealed that these metabolites primarily participate in the tricarboxylic acid cycle, arginine biosynthesis, and histidine metabolism. These findings suggest that O3 is an important factor in examining the metabolic mechanisms of cardiovascular disease, highlighting the importance of mitigating O3 to further protect AMI patients.

Bidirectional effect modifications of temperature and PM2.5 on myocardial infarction morbidity and mortality in Beijing, China from 2007 to 2021

BACKGROUND

Ambient temperatures and PM2.5 can trigger myocardial infarction (MI), while little is known about the complex interplay between these two factors on MI, especially morbidity.

OBJECTIVES

To investigate bidirectional effect modifications of temperature and PM2.5 on MI morbidity and mortality.

METHODS

A time-stratified case-crossover study was conducted utilizing high-resolution data of temperature and PM2.5, along with 498,077 MI cases from the citywide registry in Beijing, China from 2007 to 2021. A conditional logistic regression model combined with a distributed lag non-linear model was used to examine linear and categorical effect modifications of temperature and PM2.5 on MI morbidity and mortality.

RESULTS

The PM2.5 effect on MI morbidity, modified by temperature, showed a progressive increase of odds ratio from 1.013 (95 % CI: 1.001, 1.025) to 1.027 (95 % CI: 1.012, 1.042) with rising temperatures. Stratified analysis revealed a greater PM2.5 effect in high temperature strata (1.049, 95 % CI: 1.029, 1.069) compared with low strata (1.007, 95 % CI: 0.993, 1.021) on MI morbidity (PZ test<0.001). The temperature effect on MI morbidity was also modified by PM2.5, with a gradual upward risk trend observed with increasing PM2.5 concentration. Specifically, the heat wave effect was greater at high PM2.5 concentration strata (1.097, 95 % CI: 1.042, 1.155) than at low strata (0.954, 95 % CI: 0.890, 1.023) (PZ test=0.002). The cold spell effect was greater at high PM2.5 concentration strata (1.181, 95 % CI: 1.117, 1.249) than at low strata (0.883, 95 % CI: 0.740, 1.053) (PZ test=0.002). A similar bidirectional effect modification of temperature and PM2.5 was also found in MI mortality.

CONCLUSIONS

Temperature and PM2.5 bidirectionally modify their effect on MI morbidity and mortality. Elevated temperatures exacerbate PM2.5 effect, while increased concentrations of PM2.5 amplify temperature effect. The combined effect of temperatures and PM2.5 should be stressed, encompassing not only extreme conditions but also the entire range of exposures.

Air pollution and coronary atherosclerosis

The recently introduced concept of 'exposome' emphasizes the impact of non-traditional threats onto cardiovascular health. Among these, air pollutants - particularly fine particulate matter < 2.5 μm (PM2.5) - have emerged as significant environmental risk factors for cardiovascular disease and mortality. PM2.5 exposure has been shown to induce endothelial dysfunction, chronic low-grade inflammation, and cardiometabolic impairment, contributing to the development and destabilization of atherosclerotic plaques. Both short- and long-term exposure to air pollution considerably increase the incidence of ischemic heart disease (IHD)-related events, with clinical evidence linking pollution to higher mortality and adverse prognosis, especially in vulnerable populations. In this review, we explore the mechanistic pathways through which air pollutants exacerbate atherosclerotic cardiovascular disease (ASCVD) and discuss their clinical impact.Furthermore, special attention will be directed to the outcomes and prognosis of patients with pollution-aggravated coronary atherosclerosis, as well as the potential role of targeted public health interventions.

Differential effects of fine particulate matter constituents on acute coronary syndrome onset

Fine particulate matter has been linked with acute coronary syndrome. Nevertheless, the key constituents remain unclear. Here, we conduct a nationwide case-crossover study in China during 2015-2021 to quantify the associations between fine particulate matter constituents (organic matter, black carbon, nitrate, sulfate, and ammonium) and acute coronary syndrome, and to identify the critical contributors. Our findings reveal all five constituents are significantly associated with acute coronary syndrome onset. The magnitude of associations peaks on the concurrent day, attenuates thereafter, and becomes null at lag 2 day. The largest effects are observed for organic matter and black carbon, with each interquartile range increase in their concentrations corresponding to 2.15% and 2.03% increases in acute coronary syndrome onset, respectively. These two components also contribute most to the joint effects, accounting for 31% and 22%, respectively. Our findings highlight tailored clinical management and targeted control of carbonaceous components to protect cardiovascular health.

Short-term effects of air pollutants on hospitalization for childhood respiratory diseases in Suzhou City: a time-stratified case-crossover study

BACKGROUND

Short-term exposure to air pollution has been demonstrated in previous studies to correlate with respiratory disease (RD) in children. Due to regional heterogeneity, our objective was to explore the correlation between short-term exposure to ambient air pollution and hospital admissions for respiratory ailments in children in Suzhou City from January 1, 2017, to December 31, 2022, alongside assessing the influence of the COVID-19 pandemic on this relationship.

METHODS

We collected data on air pollutant levels and hospital admissions for childhood respiratory disease (RD) in Suzhou, China, from 2017 to 2022. We utilized a time-stratified case-crossover design along with a conditional logistic regression model to assess the short-term impacts of air pollutants on RD in children through stratified analysis and sensitivity analysis.

RESULTS

A total of 13,408 children with respiratory diseases were included in the study. The findings revealed significant associations between hospitalization for respiratory diseases in children and exposure to PM2.5, PM10, SO2, NO2, and CO. The maximum effect values (95%CI, best lag days) for each 10 µg/m3 increase in the concentrations of PM2.5, PM10, SO2, and NO2 were as follows: 1.017 (1.003-1.031, lag0-2), 1.015 (1.004-1.026, lag0-2), 1.117 (1.001-1.247, lag0-1), and 1.036 (1.009-1.064, lag0-7). Additionally, the maximum effect value (95%CI, best lag days) for each 1 mg/m3 increase in CO concentration was found to be 1.267 1.017-1.579, lag0-7). Stratified analysis indicated that sex, season of admission, and stage of admission did not modify these correlations significantly; however, differential effects on various age groups and sexes were primarily observed among school-age and older children as well as boys.

CONCLUSIONS

The short-term exposure to PM2.5, PM10, SO2, NO2, and CO in Suzhou, China, exhibited a positive correlation with RD hospitalization. Prior to the COVID-19 pandemic, the adverse impacts of air pollutants on hospitalizations for childhood respiratory disease were mitigated compared to the period following the pandemic. Local governments should continue promoting decisions and measures for air pollution prevention and control to reduce further pollutant concentration, which is crucial for public health in reducing the burden of childhood respiratory diseases.

Air Pollution and Myocardial Infarction-A New Smoker's Paradox?

Background/Objectives: Ambient air pollution is a significant public health concern, known to affect cardiovascular health adversely. Research has identified both long-term and short-term cardiovascular risks associated with various air pollutants, including those linked to acute coronary syndromes. However, the observed effects are rather small, with most data sourced from highly polluted regions. Methods: This study utilized a prospective registry database, documenting 12,581 myocardial infarction (MI) events in Styria, Austria from January 2007 to December 2015. Pollutants analyzed included particulate matter (PM2.5, PM10) and gases, such as NO2, CO, SO2, O3 and NOx. We employed generalized linear models to examine the interaction of each of these pollutants on the daily incidence of MI. Additionally, we conducted separate analyses for patients with specific comorbidities: diabetes mellitus (DM), arterial hypertension (HTN), heart failure with reduced ejection fraction (HFrEF), chronic obstructive pulmonary disease (COPD) and current smokers. Results: No significant associations were identified between any of the pollutants and MI incidence, both in the overall cohort and in patient subgroups with DM, HTN, HFrEF or COPD. However, among active smokers, we observed a decreased relative risk of MI associated with elevated levels of NO2, CO, SO2 and NOx on the day of MI (p < 0.01 for all pollutants). Conversely, an increased MI risk was associated with rising ozone levels (p = 0.0027). This counterintuitive finding aligns with previously published data and may suggest a new dimension to the "smoker's paradox". Conclusions: In regions with low pollution levels, air pollutants pose only minor or insignificant short-term risks for myocardial infarction. Active smokers exhibit an altered response to ambient air pollution.

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.

Impact of air pollution and noise exposure on cardiovascular disease incidence and mortality: A systematic review

Background

The relationship between environmental pollutants, specifically air pollution and noise, and cardiovascular disease is well-recognized. However, their combined effects on cardiovascular health are not fully explored.

Objectives

To review evidence on the correlation between air pollution and noise exposure and cardiovascular disease incidence and mortality.

Methods

Following the PRISMA 2020 guidelines, we identified relevant studies through multiple databases and snowballing. We focused on studies published between 2003 and 2024. Studies were selected based on a PEOS framework, with a focus on exposure to air pollution or noise and clinical cardiovascular outcomes and evaluated for bias using the ROBINS-E tool.

Results

A total of 140 studies met our inclusion criteria. Most studies suggested a consistent association between long-term exposure to air pollutants and an increased risk of cardiovascular diseases, notably ischemic heart disease and stroke. While air pollution was often studied in isolation, the interaction effects between air pollution and noise exposure were less commonly investigated, showing mixed results. The majority of these studies were conducted in Western countries, which may limit the generalizability of the findings to global populations. No studies were found to use time-updated confounders, despite the long durations over which participants were followed, which could influence the accuracy of the results. Moreover, none of the studies incorporated both residential and occupational addresses in exposure assessments, suggesting a need for future studies to include these multiple exposure points to improve measurement precision and accuracy.

Conclusion

Air pollution exposure is increasingly linked to cardiovascular disease risks. Although individual air pollution and noise exposures are recognized as significant risk factors, the combined interaction between these exposures needs further exploration.

Registration

PROSPERO (CRD42023460443).

Causal effects of noise and air pollution on multiple diseases highlight the dual role of inflammatory factors in ambient exposures

BACKGROUND

Noise and air pollution are significant environmental threats with proven adverse health effects. However, the causality between these ambient exposures and disease is still largely unknown. This study aims to provide genetic evidence for this gap and investigates the dual role of inflammatory factors, emphasizing the need for integrated public health strategies.

METHODS

We included noise and air pollution as exposures, 91 inflammatory factors as mediators, and 26 diseases as outcomes. We explored causal relationships using Mendelian randomization. To ensure the reliability, we screened single nucleotide polymorphisms (SNPs) closely associated with exposure as instrumental variables (IVs), and assessed the pleiotropy and heterogeneity of these IVs.

RESULTS

Our results suggest that "Hearing difficulty/problems with background noise" increases the risk of hypertension, bronchitis, and menopause; loud music exposure frequency increases the risk of bronchitis; noisy workplace raises the risk of hypertension, coronary heart disease, narcolepsy, and irritable bowel syndrome; NO2 increases the risk of myocardial infarction and chronic heart failure; NOx increases the risk of pneumonia and inflammatory diseases of female pelvic organs; and PM10 increases the risk of myocardial infarction, narcolepsy, and type 2 diabetes; PM2.5-10 increases the risk of developing pneumonia and type 2 diabetes. Furthermore, we found that nine inflammatory factors play a mediating role, of which four play a mediating role in increasing the risk of morbidity and eight play a mediating role in protection against ambient exposures. Finally, we selected SNPs significantly associated with exposure and outcome for enrichment analysis.

CONCLUSIONS

This study provides the first genetic evidence linking noise and air pollution to various diseases, highlighting the dual mediating role of inflammatory factors. Our findings align with the "One Health" framework, emphasizing the interconnectedness of environmental and human health. Integrated public health strategies considering these complex biological responses are essential for promoting overall well-being.

Developing and validating intracity spatiotemporal air quality health index in eastern China

BACKGROUND

Recently pilot published city-level air quality health index (AQHI) provides a useful tool for communicating short-term health risks of ambient air pollution, but fails to account for intracity spatial heterogeneity in exposure and associated population health impacts. This study aims to develop the intracity spatiotemporal AQHI (ST-AQHI) via refined air pollution-related health risk assessments.

METHODS

A three-stage analysis was conducted through integrating province-wide death surveillance data and high-resolution gridded estimates of air pollution and climate factors spanning 2016-2019 in Jiangsu Province, eastern China. First, an individual-level case-crossover design was employed to quantify the short-term risk of nonaccidental mortality associated with residential exposure to individual pollutant (i.e., PM2.5, NO2, O3, and SO2). Second, we accumulated and scaled the excess risks arising from multiple pollutants to formulate daily gridded ST-AQHI estimates at 0.1° × 0.1°, dividing exposure-related risks into low (0-3), moderate (4-6), high (7-9), and extreme high (10+) levels. Finally, the effectiveness of ST-AQHI as composite risk communication was validated through checking the dose-response associations of individual ST-AQHI exposure with deaths from nonaccidental and major cardiopulmonary causes via repeating case-crossover analyses.

RESULTS

We analyzed a total of 1,905,209 nonaccidental death cases, comprising 785,567 from circulatory diseases and 247,336 from respiratory diseases. In the first-stage analysis, for each 10-μg/m3 rise in PM2.5, NO2, O3, and SO2 exposure at lag-01 day, population risk of nonaccidental death was increased by 0.8% (95% confidence interval: 0.7%, 0.9%), 1.9% (1.7%, 2.0%), 0.4% (0.3%, 0.5%), and 4.1% (3.7%, 4.5%), respectively. Spatiotemporal distribution of ST-AQHI exhibited a consistent declining trend throughout the study period (2016-2019), with annual average ST-AQHI decreasing from 5.2 ± 1.3 to 4.0 ± 1.0 and high-risk days dropping from 15.8% (58 days) to 1.6% (6 days). Exposure associated health risks showed great intracity- and between-city heterogeneities. In the validation analysis, ST-AQHI demonstrated approximately linear, threshold-free associations with multiple death events from nonaccidental and major cardiopulmonary causes, suggesting excellent performance in predicting exposure-related health risks. Specifically, each 1-unit rise in ST-AQHI was significantly associated with an excess risk of 2.0% (1.8%, 2.1%) for nonaccidental mortality, 2.3% (2.1%, 2.6%) for overall circulatory mortality, and 2.7% (2.3%, 3.1%) for overall respiratory mortality, as well as 1.7%-3.0% for major cardiopulmonary sub-causes.

CONCLUSIONS

ST-AQHI developed in this study performed well in predicting intracity spatiotemporal heterogeneity of death risks related to multiple air pollutants, and may hold significant practical importance in communicating air pollution-related health risks to the public at the community scales.

Big Data, Big Insights: Leveraging Data Analytics to Unravel Cardiovascular Exposome Complexities

The exposome encompasses the full range of environmental exposures throughout a person's lifetime and plays an important role in cardiovascular health. Interactions with the social, natural, and built components of the exposome significantly impact cardiovascular disease prevalence and mortality. Robust data analytics, including machine learning and geospatial analysis, have advanced our understanding of how these factors converge to influence cardiovascular disease risk. The integration of multiomics platforms and advanced computational approaches enhances our ability to characterize the exposome, leading to targeted public health interventions and innovative risk reduction strategies aimed at improving cardiovascular health globally. These multiomics platforms that integrate factors such as genomics, epigenomics, clinical data, social factors, environmental factors, and wearable technology will characterize the exposome in greater detail concerning cardiovascular health. In this review, we aimed to elucidate the components of the exposome and discuss recent literature regarding their relationship to cardiovascular health.

How air pollution influences the difference between overweight and obesity: a comprehensive analysis of direct and indirect correlations

Background

Obesity, characterized by excessive or abnormal fat accumulation, is a major public health concern. Air pollution is a significant potential obesogenic factor, but the clear direct and indirect correlations between air pollution and obesity remain unclear. This study aims to provide a comprehensive understanding of the relationship between air pollution and obesity by identifying both direct and indirect causal correlations.

Methods

We used nationally representative data from the China Family Panel Survey. Air pollution concentrations were quantified as the mass (μg) of air pollutants per cubic meter (m3) based on nationally representative statistical data. To minimize statistical bias inherent in traditional methods, the direct relationship between air pollution and obesity was estimated using a regression discontinuity model, while the potential underlying mechanisms were explored through structural equation modeling.

Results

Air pollution was generally positively associated with overweight/obesity ( O R O W A Q I = 1.109, [95%CI = 1.027:1.305], O R O B A Q I = 1.032, [95%CI = 1.006:1.217], O R SO A Q I = 1.069, [95%CI = 1.014:1.208], PM2.5 and PM10 positively affected overweight/obesity ( O R O W PM 2.5 = 1.173, [95%CI = 1.094:1.252], O R O B PM 2.5 = 1.022, [95%CI = 1.016:1.028], O R SO PM 2.5 = 1.035 [95%CI = 1.015:1.055], O R O W PM 10 = 1.053, [95%CI = 1.030:1.076], O R O B PM 10 = 1.008 [95%CI = 1.006:1.010], O R SO PM 10 = 1.013 [95%CI = 1.007:1.019]), and SO2 and CO posed negative impacts on overweight/obesity ( O R O W SO 2 = 0.972, [95%CI = 0.965:0.979], O R O B SO 2 = 0.997, [95%CI = 0.996:0.998], O R SO SO 2 = 0.994, [95%CI = 0.991:0.997], O R O W C O = 0.986, [95%CI = 0.980:0.992], O R O B C O = 0.998, [95%CI = 0.997:0.999], O R SO C O = 0.999, [95%CI = 0.998:0.999]). The impact of air pollution on overweight/obesity was more significant among men, older individuals, and rural populations compared to women, younger individuals, and urban populations. Furthermore, the relationship between air pollution and overweight/obesity was mediated by social behavior determinants, including physical activity (β = 0.18, [95%CI = 0.04:0.29]), sedentary behavior (β = 0.12, [95%CI = 0.04:0.16]), sleep (β = 0.06, [95%CI = 0.02:0.13], smoking (β = 0.07, [95%CI = 0.02:0.15]), alcohol consumption (β = 0.08, [95%CI = 0.04:0.11]), and mental health (β = 0.06, [95%CI = 0.01:0.09]).

Conclusion

Air pollution was generally associated with an increased risk of overweight and obesity, with PM2.5 and PM10 having a positive influence, while SO2 and CO had a negative impact. The effect of air pollution was more pronounced among men, older individuals, and rural populations compared to women, younger individuals, and urban populations. Additionally, social behavior factors, such as physical activity, sedentary behavior, sleep, smoking, alcohol consumption, and mental health, predominantly mediated the relationship between air pollution and obesity.

High altitude air pollution and respiratory disease: Evaluating compounded exposure events and interactions

Today, air pollution remains a significant issue, particularly in high-altitude areas where its impact on respiratory disease remains incompletely explored. This study aims to investigate the association between various air pollutants and outpatient visits for respiratory disease in such regions, specifically focussing on Xining from 2016 to 2021. By analysing over 570,000 outpatient visits using a time-stratified case-crossover design and conditional logistic regression, we assessed the independent effects of pollutants like PM2.5, PM10, SO2, NO2, and CO, as well as their interactions. The evaluation of interactions employed measures such as relative excess odds due to interaction (REOI), attributable proportion due to interaction (AP), and synergy index (S). We also conducted a stratified analysis to identify potentially vulnerable populations. Our findings indicated that exposure to PM2.5, PM10, SO2, NO2, and CO significantly increased outpatient visits for respiratory disease, with odds ratios (ORs) of 2.40 % (95 % CI: 2.05 %, 2.74 %), 1.07 % (0.98 %, 1.16 %), 3.86 % (3.23 %, 4.49 %), 4.45 % (4.14 %, 4.77 %), and 6.37 % (5.70 %, 7.04 %), respectively. However, exposure to O3 did not show a significant association. We found significant interactions among PM2.5, SO2, NO2, and CO, where combined exposure further exacerbated the risk of respiratory diseases. For example, in the combination of PM2.5 and SO2, the REOI, AP, and S were 0.07 (95 % CI: 0.06, 0.09), 0.07 (0.06, 0.07), and 1.07 (1.05, 1.09), respectively. Additionally, elderly individuals and females were more sensitive to these pollutants, but no statistically significant interaction effects were observed between different age and gender groups. In conclusion, our study highlights the strong link between air pollution and respiratory disease in high-altitude areas, with combined pollutant exposure posing an even greater risk. It underscores the need for enhanced air quality monitoring and public awareness campaigns, particularly to protect vulnerable populations like the elderly and females.

Daily diurnal temperature range associated with emergency ambulance calls: a nine-year time-series study

Background

Diurnal temperature range (DTR) is associated with the increased risk of morbidity and mortality. However, the relationship between DTR and emergency ambulance calls (EACs), which more accurately and immediately reflect the health impacts of temperature changes, remains underexplored in China.

Methods

We collected daily data on EACs and meteorological factors from 2009 to 2017 in Guangzhou, China. DTR, representing the temperature range within a day, was calculated by subtracting the minimum temperature from the maximum temperature for each day. Generalized additive models were used to estimate the association between DTR and EACs for all-cause, cardiovascular diseases, and respiratory diseases. Additionally, subgroup and sensitivity analyses were conducted in our study.

Results

We found significant associations between daily DTR and EACs. The excess risks (ERs) were 0.47% (95% CI: 0.14, 0.81%) for all-cause EACs, 0.94% (95% CI: 0.46, 1.43%) for cardiovascular-related EACs, and 1.31% (95% CI: 0.76, 1.86%) for respiratory -related EACs at lag01, respectively. Subgroup analyses indicated that these associations were notably stronger among the older, males, and during the warm season. Specifically, there was an increase of 1.16% (95% CI: 0.59, 1.74%) in cardiovascular-related EACs among the older adult, compared to 0.45% (95% CI: -0.21, 1.12%) among those younger than 65 years. Among males, the increase was 1.39% (95% CI: 0.79, 1.99%), compared to 0.13% (95% CI: -0.53, 0.79%) among females. During the warm season, the increase was 1.53% (95% CI: 0.74, 2.34%), compared to 0.75% (95% CI: 0.14, 1.37%) during the cold season.

Conclusion

DTR might increase the risk of daily all-cause, cardiovascular-related, and respiratory-related EACs in Guangzhou, China. The associations were particularly strong among older adults, males, and during the warm season. Implementing public health policies is essential to mitigate the adverse health effects of DTR.

Long-term effects of air quality on hospital readmission for heart failure in patients with acute myocardial infarction

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death worldwide, with air pollution posing significant risks to cardiovascular health. The effect of air quality on heart failure (HF) readmission in acute myocardial infarction (AMI) patients is unclear.The aim of this study was to evaluate the role of a single measure of air pollution exposure collected on the day of first hospitalization.

METHODS

We retrospectively analyzed data from 12,857 acute coronary syndrome (ACS) patients (January 2015-March 2023). After multiple screenings, 4023 AMI patients were included. The air pollution data is updated by the automatic monitoring data of the national urban air quality monitoring stations in real time and synchronized to the China Environmental Monitoring Station. Cox proportional hazards regression assessed the impact of air quality indicators on admission and outcomes in 4013 AMI patients. A decision tree model identified the most susceptible groups.

RESULTS

After adjusting for confounders, NO2 (HR 1.009, 95% CI 1.004-1.015, P = 0.00066) and PM10 (HR 1.006, 95% CI 1.002-1.011, P = 0.00751) increased the risk of HF readmission in ST-segment elevation myocardial infarction (STEMI) patients. No significant effect was observed in non-STEMI (NSTEMI) patients (P > 0.05). STEMI patients had a 2.8-fold higher risk of HF readmission with NO2 > 13 μg/m3 (HR 2.857, 95% CI 1.439-5.670, P = 0.00269) and a 1.65-fold higher risk with PM10 > 55 μg/m3 (HR 1.654, 95% CI 1.124-2.434, P = 0.01064).

CONCLUSION

NO2 and PM10 are linked to increased HF readmission risk in STEMI patients, particularly when NO2 exceeds 13 μg/m3 and PM10 exceeds 55 μg/m3. Younger, less symptomatic male STEMI patients with fewer underlying conditions are more vulnerable to these pollutants.

PM2.5 chemical components are associated with in-hospital case fatality among acute myocardial infarction patients in China

Recent studies have linked the cardiovascular events with the exposure to ambient fine particulate matter (PM2.5); however, the impact of PM2.5 chemical components on acute myocardial infarction (AMI) case fatality remains poorly understood. To address this gap, we included 178,340 hospitalised patients with AMI utilising the inpatient discharge database from Sichuan, Shanxi, Guangxi, and Guangdong, China spanning 2014-2019. We evaluated exposure to PM2.5 and its components (black carbon (BC), organic matter (OM), sulphate (SO42-), nitrate (NO3-), and ammonium (NH4+)) using bilinear interpolation based on the patient's residential address. We used mixed-effects logistic regression models to investigate the associations of PM2.5 and its five components with in-hospital AMI case fatality. Per interquartile range (IQR) increment in short-term exposure (7-day average) to overall PM2.5 (odds ratio (OR): 1.086, 95 % confidence interval (CI): 1.045-1.128), SO42-(1.063, 1.024-1.104), BC (1.055, 1.023-1.089), OM (1.052, 1.019-1.086, and NO3- (1.045, 1.003-1.089) were significantly associated with high risk of in-hospital AMI case fatality. The ORs per IQR increment in long-term exposure (annual average) were 1.323 (95 % CI: 1.255-1.394) for PM2.5, followed by BC (1.271, 1.210-1.335), OM (1.243, 1.188-1.300), SO42- (1.212, 1.157-1.270), NO3- (1.116, 1.075-1.159), and NH4+ (1.068, 1.031-1.106). Our study suggests that PM2.5 chemical components might be important risk factors for in-hospital AMI case fatality, highlighting the importance of targeted reduction of PM2.5 emissions, particularly BC, OM, and SO42-.

Impact of Indoor Air Pollutants on the Cardiovascular Health Outcomes of Older Adults: Systematic Review

Indoor air pollution accounts for approximately 3.8 million inopportune deaths annually at global level. Due to spending more time indoors, children and older adults are especially susceptible to the health risks of indoor air pollution. This review seeks to summarise existing knowledge on the cardiovascular health effects of three common indoor air pollutants, namely carbon monoxide (CO), particulate matter (PM2.5 and PM10), and Nitrogen dioxide (NO2), focusing on older adults. We systematically reviewed the literature (PROSPERO CRD42024479220) on PubMed, Google Scholar, Scopus, Web of Science and Embase. The search yielded 20,914 records. Two independent reviewers screened the articles using titles, abstracts, and full-length articles written in English. Upon a detailed assessment of all the records, the review considered 38 full-length articles. Several studies reported mortality, myocardial infarction, stroke, increased hospitalisation and increased emergency room visits due to exposure to indoor air pollution. A few studies reported arrhythmias, hypertension and Ischaemic heart disease due to exposure to indoor air pollutants. The increased mortality, morbidity, hospitalization, and emergency rooms visits resulting from indoor air pollution associated CVDs makes indoor air pollution a health risk for older adults. There is, therefore, a need to synthesize information on studies relate d to how the selected indoor air pollutants affected the cardiovascular health of older adults.

Assessment of short-term effects of ambient air pollution exposure on osteoarthritis outpatient visits

The association of short-term ambient air pollution exposure with osteoarthritis (OA) outpatient visits has been unclear and no study has assessed the modifying roles of district-level characteristics in the association between ambient air pollution exposure and OA outpatient visits. We investigated the cumulative associations of ambient air pollution exposure with daily OA outpatient visits and vulnerable factors influencing the associations using data from 16 districts of Beijing, China during 2013-2019. A total of 18,351,795 OA outpatient visits were included in the analyses. An increase of 10 μg/m3 in fine particulate matter (PM2.5), inhalable particulate matter (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), maximum 8-hour moving-average ozone (8 h-O3), and 0.1 mg/m3 in carbon monoxide (CO) at representative lag days were associated with significant increases of 0.31 %, 0.06 %, 0.77 %, 0.87 %, 0.30 %, and 0.48 % in daily OA outpatient visits, respectively. Considerable OA outpatient visits were attributable to short-term ambient air pollution exposure. In addition, low temperature and high humidity aggravated ambient air pollution associated OA outpatient visits. District-level characteristics, such as population density, green coverage rate, and urbanization rate modified the risk of OA outpatient visits associated with air pollution exposure. These findings highlight the significance of controlling ambient air pollution during the urbanization process, which is useful in policy formation and implementation.

Exposure to Air Pollutants and Myocardial Infarction Incidence: A UK Biobank Study Exploring Gene-Environment Interaction

BACKGROUND

Unraveling gene-environment interaction can provide a novel insight into early disease prevention. Nevertheless, current understanding of the interplay between genetic predisposition and air pollution in relation to myocardial infarction (MI) risk remains limited. Furthermore, the potential long-term influence of air pollutants on MI incidence risk warrants more conclusive evidence in a community population.

OBJECTIVE

We investigated interactions between genetic predisposition and exposure to air pollutants on MI incidence.

METHODS

This study incorporated a sample of 456,354 UK Biobank participants and annual mean air pollution (PM 2.5 , PM 10 , NO 2 , and NO x ) from the UK Department for Environment, Food and Rural Affairs (2006-2021). The Cox proportional hazards model was employed to explore MI incidence after chronic air pollutants exposure. By quantifying genetic risk through the calculation of polygenic risk score (PRS), this study further examined the interactions between genetic risk and exposure to air pollutants in the development of MI on both additive and multiplicative scales.

RESULTS

Among 456,354 participants, 9,114 incident MI events were observed during a median follow-up of 12.08 y. Chronic exposure to air pollutants was linked with an increased risk of MI occurrence. Specifically, the hazard ratios (per interquartile range) were 1.12 (95% CI: 1.10, 1.13) for PM 2.5 , 1.20 (95% CI: 1.19, 1.22) for PM 10 , 1.13 (95% CI: 1.12, 1.15) for NO 2 , and 1.12 (95% CI: 1.11, 1.13) for NO x . In terms of the joint effects, participants with high PRS and high level of air pollution exposure exhibited the greatest risk of MI among all study participants (∼ 255 % to 324%). Remarkably, both multiplicative and additive interactions were detected in the ambient air pollutants exposure and genetic risk on the incidence of MI.

DISCUSSION

There were interactions between exposure to ambient air pollutants and genetic susceptibility on the risk of MI onset. Moreover, the joint effects of these two exposures were greater than the effect of each factor alone. https://doi.org/10.1289/EHP14291.

Long-term impact of air pollution on heart failure readmission in unstable angina patients

Cardiovascular disease remains the leading cause of death worldwide, with air pollution's impact on cardiovascular health being closely monitored. However, the specific effects of air pollution on the risk of hospital readmission for heart failure (HF) in patients with unstable angina (UA) have not been fully explored. We conducted a retrospective study involving 12,857 consecutive patients diagnosed with acute coronary syndrome (ACS) between January 2015 and March 2023. After rigorous screening, we included 8,737 patients with UA in the analysis. Furthermore, we used a Cox proportional hazards regression model to examine the relationship between air quality indicators and hospital readmission for HF in patients with UA. Additionally, a decision tree model identified air quality indicators levels that had the most significant impact on readmission for HF risk. After adjusting for confounding factors, we found that elevated levels of PM10 [hazard ratio (HR) = 1.003, 95% confidence interval (CI): 1.000-1.005, p = 0.04453] and CO (HR = 1.013, 95% CI: 1.005-1.021, p = 0.00216) were associated with an increased risk of hospital readmission for HF in UA patients. Specifically, patients exposed to PM10 levels above 112.5 µ g/m3 had a 1.61-fold higher risk of readmission for HF in UA patients. (HR = 1.609, 95% CI: 1.190-2.176, p = 0.00201), and those exposed to CO levels above 37.5 mg/m3 had a 2.70-fold higher risk of readmission for HF in UA patients. (HR = 2.681, 95% CI: 1.731-4.152, p < 0.00001). Higher concentrations of PM10 and CO significantly increased the risk of HF (HF) readmission in patients with UA after discharge, particularly when PM10 levels exceeded 112.5 ug/m3 and CO levels surpassed 37.5 ug/m3. Besides, female patients with UA, with fewer underlying diseases, were more susceptible to the adverse effects of PM10 and CO.

Acute effects of ambient nitrogen dioxide pollution on outpatient visits for neurological diseases in Xinxiang, China

BACKGROUND

Accumulating evidence suggests that exposure to air pollution acts as a potential trigger for neurological diseases (NDs), yet the current knowledge regarding the impact of ambient nitrogen dioxide (NO2) on the patients with NDs remains limited. In this study, we conducted a time-series study to evaluate the association between short-term exposure to NO2 and hospital visits for NDs in Xinxiang, China.

METHODS

An over-dispersed Poisson generalized additive model was used to analyze the association between ambient NO2 concentrations and daily outpatient visits for NDs from January 1, 2015 to December 31, 2017. The model adjusted for meteorological factors, temporal trends, day of the week, and public holidays. The concentrations of air pollutants were collected from four air quality stations in Xinxiang.

RESULTS

A total of 38, 865 outpatient visits for NDs were retrieved during the study period. 86.5% of the patients were below the age of 65 years. It was revealed that a 10 µg/m3 increase in NO2 at lag 0 was associated with a significant rise of 1.50% (95% CI: 0.45-2.56%) in outpatient visits for NDs, which was stronger during the cold season. However, the overall results from stratified analyses did not reach statistical significance.

CONCLUSIONS

Short-term exposure to NO2 is associated with increased outpatient visits for NDs. These findings underscore the need for implementing mitigating measures to reduce the neurological health effects of air pollutants.

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.

Long-term PM2.5 exposure associated with severity of angina pectoris and related health status in patients admitted with acute coronary syndrome: Modification effect of genetic susceptibility and disease history

Long-term particulate matter with aerodynamic diameters ≤2.5 μm (PM2.5) exposure has been associated with the occurrence of acute coronary syndrome (ACS). However, the impact of PM2.5 exposure and its components on the severity of angina pectoris and disease-related health status in patients hospitalized for ACS is understudied. To assess the association between long-term exposure to PM2.5 components and the angina pectoris severity in ACS patients, as well as the modification effects of genetic factors and disease history in north China. During 2017-2019, 6729 ACS patients were collected in Shandong Province and Beijing, with their angina pectoris severity evaluated using Seattle Angina Questionnaire (SAQ). The 0-3 years' average concentrations of PM2.5 and its five major components were assigned to each patient's residential address. Linear mixed-effects model, weighted quantile regression, and quantile g-computation were used to estimate the effects of both single and joint associations between PM2.5 components and SAQ scores. The interactive effect was estimated by polygenic risk scores and disease history. For each interquartile range increase in PM2.5, the overall SAQ score changed by -3.71% (95%CI: -4.54% to -2.88%), with score of angina stability more affected than angina frequency and other dimensions of angina pectoris severity. Sulfate and ammonium were major contributors to the effect of PM2.5 exposure. Significant modification effect was only observed for disease history, especially for the dimension of physical limitation. Among a series of pre-existing diseases, patients with a family history of coronary artery disease, previous percutaneous coronary intervention or coronary artery bypass grafting, and stroke were more susceptible to PM2.5 exposure than others. Greater exposure to PM2.5 is associated with more serious angina pectoris and worse disease-related health status in ACS patients. Public health and clinical priority should be given to cutting down key effective components and protecting highly vulnerable individuals.

Effects of combined exposure to fine particulate matter and cold waves and on IHD hospitalizations at low and high altitudes

Climate change and air pollution are major challenges facing the world today. Cold waves and air pollution significantly impact ischemic heart disease (IHD), but the extent of these effects at different altitudes remains unclear, especially their interactions. We collected daily meteorological, pollutant, and IHD hospitalization data from Xining and Xinxiang from 2016 to 2021. Using a time-stratified case-crossover approach, we fitted conditional Poisson regression models to assess the association between cold waves, PM2.5, and IHD hospitalizations and quantified their interactions. Additionally, we calculated the attributable fraction (AF) and attributable number (AN) of hospitalizations due to exposure to cold waves and medium to high-level PM2.5. We also performed stratified analyses by altitude, gender, and age. Both cold waves and PM2.5 were positively associated with IHD hospitalization rates in Xining and Xinxiang, but the differences between the two regions were not significant. The relative risk of cold waves was 1.15 (1.07, 1.24) in Xining and 1.16 (1.11, 1.21) in Xinxiang. In Xining, there was an interaction between cold waves and different levels of PM2.5. We estimated the attributable fraction due to the joint exposure of cold waves and PM2.5 to be 0.14-0.49 in Xining and 0.26-0.36 in Xinxiang. Older adults and males faced higher risks. This study highlights the importance of reducing PM2.5 exposure and optimizing extreme weather warning systems and suggests further exploration of the impacts of individual behaviors and regional characteristics on IHD.

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.

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.

Leisure-time physical activity and the incidence of atrial fibrillation in senior adults: a prospective cohort study

OBJECTIVE

Whether physical activity could reduce the risk of atrial fibrillation (AF) remains unclear. This study was to investigate the relationship of leisure-time physical activity (LTPA) with AF incidence among Chinese older adults.

METHODS

A total of 3253 participants aged ≥60 years from the Guangzhou Heart Study were successfully followed between March 2018 and September 2019. LTPA was assessed using a modified Global Physical Activity Questionnaire. AF was ascertained by 12-lead electrocardiograms, 24-hour single-lead Holter and clinical examination. The Cox proportional hazards model was used to the estimate hazard ratio (HR) and 95% confidence interval (CI) after adjustment for confounders, and the population-attributable fraction (PAF) was estimated.

RESULTS

A total of 76 (2.34%) new-onset cases of AF were identified during a median of 31.13 months of follow-up. After adjustment for confounders, subjects who had LTPA at least 10.0 metabolic equivalent (MET)-hours/week had a 55% lower risk of developing AF (HR: 0.45, 95%CI: 0.25-0.81), and at least 20 MET-hours/week reduced the risk by 45% (HR: 0.55, 95%CI: 0.34-0.92). At least 11% (PAF: 11%, 95%CI: 0%-20%) or 14% (PAF: 14%, 95%CI: 0%-26%) of AF cases could be avoided, respectively, if the subjects do LTPA at least 10 MET-hours/week or 20 MET-hours/week. A significant exposure-response trend was also observed between LTPA and AF risk (Plinear-trend = 0.002). For a specific LTPA, doing housework was associated with a 43% reduced risk, while engaging in ball games was associated with an increased risk.

CONCLUSION

This prospective cohort study indicated that a higher LTPA volume was associated with a lower AF risk in Chinese older adults.

Enhancing the health benefits of air quality improvement: a comparative study across diverse scenarios

In many studies, linear methods were used to calculate health benefits of air quality improvement, but the relationship between air pollutants and diseases may be complex and nonlinear. In addition, previous studies using reference number as average number of diseases may overestimate the health benefits. Therefore, the nonlinear model estimation and resetting of the reference number were very important. Hospital admission data for coronary heart disease (CHD), meteorological data, and air pollutant data of Zibo City from 2015 to 2019 were collected. The generalized additive model (GAM) was used to explore the association between air pollutants and hospital admission for CHD, and to evaluate the effects on health benefits under different reference number settings. A total of 21,105 hospitalized cases for CHD were reported in Zibo during the study period. The results of the GAM showed there was a log-linear exposure-response relationship between O3 and hospital admissions for CHD, with RR (relative risk) of 1.0143 (95% CI: 1.0047 ~ 1.0239). There were log-nonlinear exposure-response relationships between PM10, PM2.5, SO2, and hospital admissions for CHD. With the increase of pollutants concentrations, the risk for hospital admission showed a trend of increasing first and then decreasing. Compared with the average hospital admissions as the reference number, health benefits calculated by hospital admissions predicted by the GAM model yielded lower. Using the World Health Organization air quality guidelines as reference, attributable fractions of O3, PM10, and PM2.5 were 1.97% (95% CI: 0.63 ~ 3.40%), 11.82% (95% CI: 8.60 ~ 15.24%), and 11.82% (95% CI: 8.79 ~ 15.04%), respectively. When quantifying health benefits brought by improving air quality, corresponding calculation methods should first be determined according to the exposure-response relationships between air pollutants and outcomes. Then, applying the average hospital admissions as reference number may overestimate health benefits resulting from improved air quality.

Differential associations of fine and coarse particulate air pollution with cause-specific pneumonia mortality: A nationwide, individual-level, case-crossover study

BACKGROUND

The connections between fine particulate matter (PM2.5) and coarse particulate matter (PM2.5-10) and daily mortality of viral pneumonia and bacterial pneumonia were unclear.

OBJECTIVES

To distinguish the connections between PM2.5 and PM2.5-10 and daily mortality due to viral pneumonia and bacterial pneumonia.

METHODS

Using a comprehensive national death registry encompassing all areas of mainland China, we conducted a case-crossover investigation from 2013 to 2019 at an individual level. Residential daily particle concentrations were evaluated using satellite-based models with a spatial resolution of 1 km. To analyze the data, we employed the conditional logistic regression model in conjunction with polynomial distributed lag models.

RESULTS

We included 221,507 pneumonia deaths in China. Every interquartile range (IQR) elevation in concentrations of PM2.5 (lag 0-2 d, 37.6 μg/m3) was associated with higher magnitude of mortality for viral pneumonia (3.03%) than bacterial pneumonia (2.14%), whereas the difference was not significant (p-value for difference = 0.38). An IQR increase in concentrations of PM2.5-10 (lag 0-2 d, 28.4 μg/m3) was also linked to higher magnitude of mortality from viral pneumonia (3.06%) compared to bacterial pneumonia (2.31%), whereas the difference was not significant (p-value for difference = 0.52). After controlling for gaseous pollutants, their effects were all stable; however, with mutual adjustment, the associations of PM2.5 remained, and those of PM2.5-10 were no longer statistically significant. Greater magnitude of associations was noted in individuals aged 75 years and above, as well as during the cold season.

CONCLUSION

This nationwide study presents compelling evidence that both PM2.5 and PM2.5-10 exposures could increase pneumonia mortality of viral and bacterial causes, highlighting the more robust effects of PM2.5 and somewhat higher sensitivity of viral pneumonia.

Palliative effects of carnosol on lung-deposited pollutant particles-induced thrombogenicity and vascular injury in mice

The toxicity of inhaled particulate air pollution perseveres even at lower concentrations than those of the existing air quality limit. Therefore, the identification of safe and effective measures against pollutant particles-induced vascular toxicity is warranted. Carnosol is a bioactive phenolic diterpene found in rosemary herb, with anti-inflammatory and antioxidant actions. However, its possible protective effect on the thrombotic and vascular injury induced by diesel exhaust particles (DEP) has not been studied before. We assessed here the potential alleviating effect of carnosol (20 mg/kg) administered intraperitoneally 1 h before intratracheal (i.t.) instillation of DEP (20 μg/mouse). Twenty-four hours after the administration of DEP, various parameters were assessed. Carnosol administration prevented the increase in the plasma concentrations of C-reactive protein, fibrinogen, and tissue factor induced by DEP exposure. Carnosol inhibited DEP-induced prothrombotic effects in pial microvessels in vivo and platelet aggregation in vitro. The shortening of activated partial thromboplastin time and prothrombin time induced by DEP was abated by carnosol administration. Carnosol inhibited the increase in pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor α) and adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin) in aortic tissue. Moreover, it averted the effects of DEP-induced increase of thiobarbituric acid reactive substances, depletion of antioxidants and DNA damage in the aortic tissue. Likewise, carnosol prevented the decrease in the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) caused by DEP. We conclude that carnosol alleviates DEP-induced thrombogenicity and vascular inflammation, oxidative damage, and DNA injury through Nrf2 and HO-1 activation.

Short-term effects of nitrogen dioxide on inpatient acute myocardial infarction in Lanzhou, China

Nitrogen dioxide (NO2) represents a deleterious effect on acute myocardial infarction (AMI), but few relevant studies have been conducted in China. We aim to evaluate the acute effects of NO2 exposure on hospitalization for AMI in Lanzhou, China. In this study, we applied a distributional lag nonlinear model (DLNM) to assess the association between NO2 exposure and AMI hospitalization. We explored the sensitivity of various groups through stratified analysis by gender, age, and season. The daily average concentration of NO2 is 47.50 ± 17.38 µg/m3. We observed a significant exposure-response relationship between NO2 concentration and AMI hospitalization. The single pollutant model analysis shows that NO2 is positively correlated with AMI hospitalization at lag1, lag01, lag02, and lag03. The greatest lag effect estimate occurs at lag01, where a 10 µg/m3 increase in NO2 concentrations is significantly associated with a relative risk (RR) of hospitalization due to AMI of 1.027 [95% confidence interval (CI): 1.013, 1.042]. The results of the stratified analysis by gender, age, and season indicate that males, those aged ≥65 years, and the cold season are more sensitive to the deleterious effects caused by NO2 exposure. Short-term exposure to NO2 can enhance the risk of AMI hospitalization in urban Lanzhou.Implications: Exposure to particulate matter can lead to an increased incidence of AMI. Our study once again shows that NO2 exposure increases the risk of AMI hospital admission. AMI is a common and expensive fatal condition. Reducing NO2 exposure will benefit cardiovascular health and save on healthcare costs.

AMPA receptor inhibition alleviates inflammatory response and myocardial apoptosis after myocardial infarction by inhibiting TLR4/NF-κB signaling pathway

Myocardial infarction leads to myocardial inflammation and apoptosis, which are crucial factors leading to heart failure and cardiovascular dysfunction, eventually resulting in death. While the inhibition of AMPA receptors mitigates inflammation and tissue apoptosis, the effectiveness of this inhibition in the pathophysiological processes of myocardial infarction remains unclear. This study investigated the role of AMPA receptor inhibition in myocardial infarction and elucidated the underlying mechanisms. This study established a myocardial infarction model by ligating the left anterior descending branch of the coronary artery in Sprague-Dawley rats. The findings suggested that injecting the AMPA receptor antagonist NBQX into myocardial infarction rats effectively alleviated cardiac inflammation, myocardial necrosis, and apoptosis and improved their cardiac contractile function. Conversely, injecting the AMPA receptor agonist CX546 into infarcted rats exacerbated the symptoms and tissue damage, as reflected by histopathology. This agonist also stimulated the TLR4/NF-κB pathway, further deteriorating cardiac function. Furthermore, the investigations revealed that AMPA receptor inhibition hindered the nuclear translocation of P65, blocking its downstream signaling pathway and attenuating tissue inflammation. In summary, this study affirmed the potential of AMPA receptor inhibition in countering inflammation and tissue apoptosis after myocardial infarction, making it a promising therapeutic target for mitigating myocardial infarction.

Differentiating the impact of fine and coarse particulate matter on cause-specific cerebrovascular mortality: An individual-level, case-crossover study

BACKGROUND AND OBJECTIVES

Many studies suggested that short-term exposure to fine particulate matter (PM2.5) and coarse particulate matter (PM2.5-10) was linked to elevated risk of cerebrovascular disease. However, little is known about the potentially differential effects of PM2.5 and PM2.5-10 on various types of cerebrovascular disease.

METHODS

We collected individual cerebrovascular death records for all residents in Shanghai, China from 2005 to 2021. Residential daily air pollution data were predicted from a satellite model. The associations between particulate matters (PM) and cerebrovascular mortality were investigated by an individual-level, time-stratified, case-crossover design. The data was analyzed by the conditional logistic regression combined with the distributed lag model with a maximum lag of 7 days. Furthermore, we explored the effect modifications by sex, age and season.

RESULTS

A total of 388,823 cerebrovascular deaths were included. Monotonous increases were observed for mortality of all cerebrovascular diseases except for hemorrhagic stroke. A 10 μg/m3 rise in PM2.5 was related to rises of 1.35% [95% confidence interval (CI): 1.04%, 1.66%] in mortality of all cerebrovascular diseases, 1.84% (95% CI: 1.25%, 2.44%) in ischemic stroke, 1.53% (95% CI: 1.07%, 1.99%) in cerebrovascular sequelae and 1.56% (95% CI: 1.08%, 2.05%) in ischemic stroke sequelae. The excess risk estimates per each 10 μg/m3 rise in PM2.5-10 were 1.47% (95% CI: 1.10%, 1.84%), 1.53% (95% CI: 0.83%, 2.24%), 1.93% (95% CI: 1.38%, 2.49%) and 2.22% (95% CI: 1.64%, 2.81%), respectively. The associations of both pollutants with all cerebrovascular outcomes were robust after controlling for co-pollutants. The associations were greater in females, individuals > 80 years, and during the warm season.

CONCLUSIONS

Short-term exposures to both PM2.5 and PM2.5-10 may independently increase the mortality risk of cerebrovascular diseases, particularly of ischemic stroke and stroke sequelae.

Short-Term Exposure to Air Pollution and the Incidence and Mortality of Stroke: A Meta-Analysis

BACKGROUND

The relationship between short-term exposure to various air pollutants [particulate matter <10 μm (PM 10 ), particulate matter <2.5 μm (PM 2.5 ), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), carbon monoxide, and ozone (O 3 )] and the incidence and mortality of stroke remain unclear.

REVIEW SUMMARY

We conducted a comprehensive search across databases, including PubMed, Web of Science, and others. A random-effects model was employed to estimate the odds ratios (OR) and their 95% CIs. Short-term exposure to PM 10 , PM 2.5 , NO 2 , SO 2 , and O 3 was associated with increased stroke incidence [per 10 μg/m 3 increase in PM 2.5 : OR = 1.005 (95% CI: 1.004-1.007), per 10 μg/m 3 increase in PM 10 : OR = 1.006 (95% CI: 1.004-1.009), per 10 μg/m 3 increase in SO 2 : OR = 1.034 (95% CI: 1.020-1.048), per 10 μg/m 3 increase in NO 2 : OR = 1.029 (95% CI: 1.015-1.043), and O 3 for per 10 μg/m 3 increase: OR: 1.006 (95% CI: 1.004-1.007)]. In addition, short-term exposure to PM 2.5 , PM 10 , SO 2, and NO 2 was correlated with increased mortality from stroke [per 10 μg/m 3 increase in PM 2.5 : OR = 1.010 (95% CI: 1.006-1.013), per 10 μg/m 3 increase in PM 10 : OR = 1.004 (95% CI: 1.003-1.006), per 10 μg/m 3 increase in SO 2 : OR = 1.013 (95% CI: 1.007-1.019) and per 10 μg/m 3 increase in NO 2 : OR = 1.012 (95% CI: 1.008-1.015)].

CONCLUSION

Reducing outdoor air pollutant levels may yield a favorable outcome in reducing the incidence and mortality associated with strokes.

Personal Strategies to Reduce the Cardiovascular Impacts of Environmental Exposures

Ubiquitous environmental exposures increase cardiovascular disease risk via diverse mechanisms. This review examines personal strategies to minimize this risk. With regard to fine particulate air pollution exposure, evidence exists to recommend the use of portable air cleaners and avoidance of outdoor activity during periods of poor air quality. Other evidence may support physical activity, dietary modification, omega-3 fatty acid supplementation, and indoor and in-vehicle air conditioning as viable strategies to minimize adverse health effects. There is currently insufficient data to recommend specific personal approaches to reduce the adverse cardiovascular effects of noise pollution. Public health advisories for periods of extreme heat or cold should be observed, with limited evidence supporting a warm ambient home temperature and physical activity as strategies to limit the cardiovascular harms of temperature extremes. Perfluoroalkyl and polyfluoroalkyl substance exposure can be reduced by avoiding contact with perfluoroalkyl and polyfluoroalkyl substance-containing materials; blood or plasma donation and cholestyramine may reduce total body stores of perfluoroalkyl and polyfluoroalkyl substances. However, the cardiovascular impact of these interventions has not been examined. Limited utilization of pesticides and safe handling during use should be encouraged. Finally, vasculotoxic metal exposure can be decreased by using portable air cleaners, home water filtration, and awareness of potential contaminants in ground spices. Chelation therapy reduces physiological stores of vasculotoxic metals and may be effective for the secondary prevention of cardiovascular disease.

Green and blue space exposure and non-communicable disease related hospitalizations: A systematic review

The global increase in non-communicable diseases (NCDs) presents a critical public health concern. Emerging evidence suggests that exposure to natural environments may reduce the risk of developing NCDs through multiple pathways. The present systematic review aims to synthesize and evaluate the observational evidence regarding associations between exposure to green and blue spaces and hospital admissions related to NCDs. A comprehensive literature search strategy was conducted in Embase (Ovid), PubMed, and Web of Science. The risk of bias and quality of the evidence were assessed using The Navigation Guide methodology, an approach specifically designed for environmental health research. Of 3060 search results, 17 articles were included. Notably, the majority of the studies (n = 14; 82.4%) were published from 2020 onwards. Most studies were conducted in the United States (n = 6; 35.3%) and China (n = 4; 23.5%). Exposure to green spaces was assessed through all studies, while only three included blue spaces. In terms of study design, cohort design was employed in nearly half of the studies (n = 8; 47.1%), followed by case-crossover design (n = 3, 17.6%). Over 75% of the included studies (n = 13) had a high or probably high rating in the risk of bias assessment. The studies encompassed diverse NCD outcome domains; cardiovascular diseases (CVDs) (n = 10), respiratory diseases (RSDs) (n = 2), heat-related diseases (n = 1), metabolic diseases (n = 2), cancer (n = 1), neurodegenerative diseases (NDDs) (n = 2), and mental health disorders (n = 2). The present review suggests that a clear link between blue space exposure and NCD hospital admissions is not evident. However, exposure to green spaces appears to predominantly have a protective effect, although the direction of the association varies across different outcome domains. The heterogeneity among the outcome domains together with the limited number of studies, emphasizes the need for more robust evidence.

Exploring the Modifying Role of GDP and Greenness on the Short Effect of Air Pollutants on Respiratory Hospitalization in Beijing

It is unclear whether Gross Domestic Product (GDP) and greenness have additional modifying effects on the association between air pollution and respiratory system disease. Utilizing a time-stratified case-crossover design with a distributed lag linear model, we analyzed the association between six pollutants (PM2.5, PM10, NO2, SO2, O3, and CO) and 555,498 respiratory hospital admissions in Beijing from 1st January 2016 to 31st December 2019. We employed conditional logistic regression, adjusting for meteorological conditions, holidays and influenza, to calculate percent change of hospitalization risk. Subsequently, we performed subgroup analysis to investigate potential effect modifications using a two-sample z test. Every 10 μg/m3 increase in PM2.5, PM10, NO2, SO2, and O3 led to increases of 0.26% (95%CI: 0.17%, 0.35%), 0.15% (95%CI: 0.09%, 0.22%), 0.61% (95%CI: 0.44%, 0.77%), 1.72% (95%CI: 1.24%, 2.21%), and 0.32% (95%CI: 0.20%, 0.43%) in admissions, respectively. Also, a 1 mg/m3 increase in CO levels resulted in a 2.50% (95%CI: 1.96%, 3.04%) rise in admissions. The links with NO2 (p < 0.001), SO2 (p < 0.001), O3 (during the warm season, p < 0.001), and CO (p < 0.001) were significantly weaker among patients residing in areas with higher levels of greenness. No significant modifying role of GDP was observed. Greenness can help mitigate the effects of air pollutants, while the role of GDP needs further investigation.

Short-term air pollution exposure and mechanisms of plaque instability in acute coronary syndromes: An optical coherence tomography study

BACKGROUND AND AIMS

Air pollution is emerging as an important risk factor for acute coronary syndrome (ACS). In this study, we investigated the association between short-term air pollution exposure and mechanisms of coronary plaque instability evaluated by optical coherence tomography (OCT) imaging in ACS patients.

METHODS

Patients with ACS undergoing OCT imaging were retrospectively selected. Mechanism of culprit lesion instability was classified as plaque rupture (PR) or intact fibrous cap (IFC) by OCT. Based on each case's home address, the mean daily exposures to several pollutants, including particulate matter 2.5 (PM2.5), on the same day of ACS and in the immediate days (up to 6 days) prior to the index ACS, were collected.

RESULTS

139 ACS patients were included [69 (49.6%) had PR and 70 (50.4%) IFC]. Patients with PR, compared to those with IFC, had higher PM2.5 exposure levels on the same day of ACS, without differences in the immediate 6 days before index ACS. At multivariate analysis, PM2.5 exposure on the same day of ACS was the only independent predictor of PR [OR = 1.912 per SD (8.6 μg/m3), CI95 % (1.087-3.364), p = 0.025]. Patients with PR presented a steady increase in PM2.5 daily exposure levels in the days preceding the occurrence of ACS, with a peak the day of ACS (p for trend = 0.042) CONCLUSIONS: This study demonstrates for the first time that a higher short-term PM2.5 exposure, on the same day of ACS, is associated with an increased risk of PR as a pathobiological mechanism of coronary plaque instability.

Hourly Heat Exposure and Acute Ischemic Stroke

Importance

Previous studies have demonstrated the associations of daily high temperature with hospitalizations and mortality from ischemic stroke, but the hourly association of ambient heat and acute ischemic stroke (AIS) onset has been rarely examined.

Objectives

To evaluate the association between hourly high ambient temperature and the onset of AIS.

Design, Setting, and Participants

This time-stratified case-crossover study was conducted using a nationwide registry that collects data from more than 200 stroke centers in China. Participants were adult patients with AIS who were hospitalized in the warm seasons between January 1, 2019, and December 31, 2021.

Exposures

Hourly temperature and single-hour temperature exposure lag up to 24 hours before the AIS onset (lag 0 hours to lag 24 hours).

Main Outcomes and Measures

The main outcome was onset of AIS. Associations between hourly mean temperatures and AIS onset were analyzed using conditional logistic regression integrated with the distributed lag nonlinear model. Stratification analyses were applied to examine potential association modifiers. Several sensitivity analyses were conducted to examine the robustness of the results.

Results

A total of 82 455 patients with AIS (mean [SD] age, 65.8 [11.9] years; 52 267 males [63.4%]) were included in the final analysis. A monotonically increasing risk of AIS onset was associated with higher temperatures. The excess AIS risk occurred immediately at lag 0 hours and persisted for 10 hours. Compared with the reference temperature (12.1 °C), the cumulative odds ratio (OR) over lag 0 to 10 hours of AIS onset associated with extremely high temperature (33.3 °C) was 1.88 (95% CI, 1.65-2.13) nationwide. The exposure-response curve was steeper in the north than in the south (OR, 1.80 [95% CI, 1.53-2.11] vs 1.57 [95% CI, 1.31-1.87]). The ORs were greater for males and patients with a history of dyslipidemia or atrial fibrillation, but the differences were not significant.

Conclusions and Relevance

Results of this study suggest that hourly heat exposure is associated with increased risk of AIS onset. This finding may benefit the formulation of public health strategies to reduce cerebrovascular risk associated with high ambient temperature under global warming.

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.

Long-term effects of air pollutants on deaths in a semi-urban city in Northwestern Turkey: a time series analysis

To examine the associations between daily variations of coarse Particulate Matter(PM10) and/or sulfur dioxide(SO2) and mortality. The Poisson Generalized Linear Model(GLM) was employed to analyze the relationship between ambient air pollutants such as PM10 and SO2 and mortality. For each 10 μg/m3 increase in PM10, the overall mortality risk was found to be 1.022-fold high on the previous-eighth-day(lag 7) (RR, 95%CI:1.002-1.042) in the unadjusted model; 1.031-fold high in men (RR, 95%CI:1.005-1.058); 1.024-fold high in those aged 65 and over (RR, 95%CI:1.001-1.048). Also, the risk of death in men was 1.028-fold high in the model adjusted on the previous- eighth-day(lag 7) (RR, 95%CI:1.002-1.055). Mortality risk was found to be 1.088-fold high in 10 μg/m3 increase in SO2 under 65 years in males in the previous-third-day(lag 2) in the unadjusted model, and the risk of death was found to be 1.086-fold (RR, 95%CI:1.007-1.164) high in males in the adjusted model.   .

Ambient PM2.5 and cardiopulmonary mortality in the oldest-old people in China: A national time-stratified case-crossover study

BACKGROUND

Evidence on the associations of fine particulate matter (PM2.5) with cardiopulmonary mortality in the oldest-old (aged 80+ years) people remains limited.

METHODS

We conducted a time-stratified case-crossover study of 1,475,459 deaths from cardiopulmonary diseases in China to estimate the associations between short-term exposure to ambient PM2.5 and cardiopulmonary mortality among the oldest-old people.

FINDINGS

Each 10 μg/m3 increase in PM2.5 concentration (6-day moving average [lag05]) was associated with higher mortality from cardiopulmonary diseases (excess risks [ERs] = 1.69%, 95% confidence interval [CI]: 1.54%, 1.84%), cardiovascular diseases (ER = 1.72%, 95% CI: 1.54%, 1.90%), and respiratory diseases (ER = 1.62%, 95% CI: 1.33%, 1.91%). Compared to the other groups, females (ER = 1.94%, 95% CI: 1.73%, 2.15%) (p for difference test = 0.043) and those aged 95-99 years (ER = 2.31%, 95% CI: 1.61%, 3.02%) (aged 80-85 years old was the reference, p for difference test = 0.770) presented greater mortality risks. We found 14 specific cardiopulmonary causes associated with PM2.5, out of which emphysema (ER = 3.20%, 95% CI: 1.57%, 4.86%) had the largest association. Out of the total deaths, 6.27% (attributable fraction [AF], 95% CI: 5.72%, 6.82%) were ascribed to short-term PM2.5 exposure.

CONCLUSIONS

This study provides evidence of PM2.5-induced cardiopulmonary mortality and calls for targeted prevention actions for the oldest-old people.

FUNDING

This work was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, the Foreign Expert Program of the Ministry of Science and Technology, the Natural Science Foundation of Guangdong, China, and the Science and Technology Program of Guangzhou.

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.

Associations between ultrafine particle pollution and daily outpatient visits for respiratory diseases in Shanghai, China: a time-series analysis

Previous epidemiological studies have linked short-term exposure to particulate matter with outpatient visits for respiratory diseases. However, evidence on ultrafine particle (UFP) is still scarce in China. To investigate the association between short-term UFP exposure and outpatient visits for respiratory diseases as well as the corresponding lag patterns, information on outpatient visits for main respiratory diseases during January 1, 2017, to December 31, 2019 was collected from electronic medical records of two large tertiary hospitals in Shanghai, China. Generalized additive models employing a Quasi-Poisson distribution were employed to investigate the relationships between UFP and respiratory diseases. We computed the percentage change and its corresponding 95% confidence interval (CI) for outpatient visits related to respiratory diseases per interquartile range (IQR) increase in UFP concentrations. Based on a total of 1,034,394 hospital visits for respiratory diseases in Shanghai, China, we found that the strongest associations of total UFP with acute upper respiratory tract infection (AURTI), bronchitis, chronic obstructive pulmonary disease (COPD), and pneumonia occurred at lag 03, 03, 0, and 03 days, respectively. Each IQR increase in the total UFP concentrations was associated with increments of 9.02% (95% CI: 8.64-9.40%), 3.94% (95% CI: 2.84-5.06%), 4.10% (95% CI: 3.01-5.20%), and 10.15% (95% CI: 9.32-10.99%) for AURTI, bronchitis, COPD, and pneumonia, respectively. Almost linear concentration-response relationship curves without apparent thresholds were observed between total UFP and outpatient-department visits for four respiratory diseases. Stratified analyses illustrated significantly stronger associations of total UFP with AURTI, bronchitis, and pneumonia among female patients, while that with COPD was stronger among male patients. After adjustment of criteria air pollutants, these associations all remained robust. This time-series study indicates that short-term exposure to UFP was associated with increased risk of hospital visits for respiratory diseases, underscoring the importance of reducing ambient UFP concentrations for respiratory diseases control and prevention.

Assessing the short-term effects of PM2.5 and O3 on cardiovascular mortality using high-resolution exposure: a time-stratified case cross-over study in Southwestern China

Air pollution is a major risk factor of cardiovascular disease (CVD). To date, limited studies have estimated the effects of ambient air pollution on CVD mortality using high-resolution exposure assessment, which might fail to capture the spatial variation in exposure and introduce bias in results. Besides, the three-year action plan (TYAP, 2018-2020) was released; thus, the constitution and health effect of air pollutants may have changed. In this study, we estimated the short-term effect exposed to particulate matters with parameter less than 2.5 µm (PM2.5) and ozone (O3) with 0.05° × 0.05° resolution on CVD mortality and measured the influence of TYAP in the associations. We used random forest models with spatial weight matrices to attain high-resolution pollutant concentrations and conditional Poisson regression to assess the relationship between air pollution and cardiovascular mortality. With an increase of 10 µg/m3 in PM2.5 and O3 during 2018-2021 in the Sichuan Basin (SCB), CVD mortality increased 1.0134 (95% CI 1.0102, 1.0166) and 1.0083 (95% CI 1.0060, 1.0107), respectively, using high-resolution air pollutant concentration, comparing to 1.0070 (95% CI 1.0052, 1.0087) and 1.0057 (95% CI 1.0037, 1.0078) using data from air quality monitoring stations (AQMs). After TYAP, the relative risk (RR) due to PM2.5 rose up to 1.0149 (95% CI 1.0054, 1.0243), and the RR due to O3 rose up to 1.0089 (95% CI 1.0030, 1.0148) in Sichuan Province. We found significantly positive association of cardiovascular mortality and air pollution in Sichuan Province. And using high-resolution exposure would be more accurate to estimate the effect of air pollution on CVD. After TYAP, the cardiovascular mortality risk estimation due to PM2.5 decreased in elderly in SCB, and the risk due to O3 increased in Sichuan Province.