Association between short-term exposure to ambient fine particulate matter and myocardial injury in the CATHGEN cohort

Associations among NMR-measured inflammatory and metabolic biomarkers and accelerated aging in cardiac catheterization patients

Research into aging has grown substantially with the creation of molecular biomarkers of biological age that can be used to determine age acceleration. Concurrently, nuclear magnetic resonance (NMR) assessment of biomarkers of inflammation and metabolism provides researchers with new ways to examine intermediate risk factors for chronic disease. We used data from a cardiac catheterization cohort to examine associations between biomarkers of cardiometabolic health and accelerated aging assessed using both gene expression (Transcriptomic Age) and DNA methylation (Hannum Age, GrimAge, Horvath Age, and Phenotypic Age). Linear regression models were used to associate accelerated aging with each outcome (cardiometabolic health biomarkers) while adjusting for chronological age, sex, race, and neighborhood socioeconomic status. Our study shows a robust association between GlycA and GrimAge (5.71, 95% CI = 4.36, 7.05, P = 7.94 × 10-16), Hannum Age (1.81, 95% CI = 0.65, 2.98, P = 2.30 × 10-3), and Phenotypic Age (2.88, 95% CI = 1.91, 3.87, P = 1.21 × 10-8). We also saw inverse associations between apolipoprotein A-1 and aging biomarkers. These associations provide insight into the relationship between aging and cardiometabolic health that may be informative for vulnerable populations.

Effects of low-level air pollution exposures on hospital admission for myocardial infarction using multiple causal models

Myocardial infarctions have been associated with PM2.5, and more recently with NO2 and O3, however counterfactual designs have been lacking and argument continues over the extent of confounding control. Here we introduce a doubly robust, counterfactual-based approach that deals with nonlinearity and interactions in associations between confounders and both outcome and exposure, as well as a double negative controls approach that capture omitted confounders. We used data from over 4 million admissions for myocardial infarction in the US Medicare population between 2000 and 2016 and linked them by ZIP code of residence to high resolution predictions of annual PM2.5, NO2, and O3. We computed the counts of admissions for each ZIP code-year. In the doubly robust approach, we divided each pollutant into deciles, and for each decile, we fitted a gradient boosting machine model to estimate the effects of covariates, including the co-pollutants, on the counts. We used these models to predict, for all ZIP code-years, the expected counts had everyone be exposed in that decile. We also estimated the probability of being in that decile given all covariates, again with a gradient boosting machine, and used inverse probability weights to compute the weighted average rate of MI admission in each decile. In the negative control approach, for each pollutant, we fitted a quasi-Poisson model to estimate the exposure effect, adjusting for covariates including the co-pollutants, and negative exposure and outcome controls to control for unmeasured confounding. Each 1-μg/m3 increase in annual PM2.5 increased the admission for MI by 1.37 cases per 10,000 person-years (95% CI: 1.20, 1.54) in the doubly robust approach, and by 0.69 cases (95% CI 0.60, 0.78) using the negative control approach. Elevated risks were seen even below annual PM2.5 level of 8 μg/m3. Results for NO2 and O3 were inconsistent.

Higher mold levels found in in the deteriorated housing in the Sun Valley neighborhood of Denver, Colorado compared to other Denver housing and higher rates of health insurance claims for some diseases documented for the Sun Valley residents compared to other Denver residents

The Sun Valley Homes public housing in Denver, Colorado (CO) will be replaced because of its deteriorated condition. Our goal was to document the mold contamination and particulate matter (PM2.5) concentrations in Sun Valley homes and the circulatory and respiratory health of Sun Valley compared to all Denver residents (total 2761 and 1,049,046, respectively) based on insurance claims data for 2015 to 2019. Mold contamination in Sun Valley homes (n = 49) was quantified using the Environmental Relative Moldiness Index (ERMI) scale. Indoor PM2.5 concentrations were measured in Sun Valley homes (n = 11) using time-integrated, filter-based samples and quantified using gravimetric analysis. Outdoor PM2.5 concentrations data were obtained from a near-by United States Environmental Protection Agency monitoring station. In Sun Valley homes, the average ERMI value was 5.25 compared to -1.25 for other Denver homes. The PM2.5 median concentration inside Sun Valley homes was 7.6 μg/m3 (interquartile range - 6.4 μg/m3). The ratio of indoor to outdoor concentrations of PM2.5 was 2.3 (interquartile range - 1.5). In the last five years, ischemic heart disease was significantly more likely for Denver compared to Sun Valley residents. However, acute upper respiratory infections, chronic lower respiratory diseases and asthma were all significantly more likely for Sun Valley than Denver residents. Since the process of replacing and occupying the new housing will take several years, the next phase of the study will not occur until that process is complete.

Association of greenness exposure with coronary artery stenosis and biomarkers of myocardial injury in patients with myocardial infarction

BACKGROUND

Greenness has been linked to cardiovascular health; however, limited evidence is available regarding its association with coronary artery stenosis and biomarkers of myocardial injury. We aimed to assess these associations and examine their modification and mediation effects in patients with myocardial infarction (MI).

METHODS

This study included 2030 patients with MI. The normalized difference vegetation index (NDVI) was used to characterize greenness exposure. We used a logistic regression model to explore the relationship between coronary artery stenosis and residential greenness, and applied linear regression models to assess the association of greenness with biomarkers of myocardial injury. The bootstrap method was used to explore whether potential variables mediated the associations. To further investigate the exposure-response curve describing these relationships, we developed restricted cubic spline models.

RESULT

Compared to the lowest quartile of NDVI, the odds ratio (OR) (95 % confidence interval [CI]) for severe stenosis (≥75 % stenosis) was 0.68 (95 % CI: 0.47 to 0.98) for the third quartile. Participants in the highest greenness exposure quartile had lower levels of cardiac troponin I (cTnI), creatine kinase (CK), and creatine kinase isoenzyme (CKMB) than those in the lowest quartile (β = -0.22, 95 % CI: -0.40 to -0.05; β = -0.13, 95 % CI: -0.22 to -0.04; β = -0.07, 95 % CI: -0.14 to -0.003). The association between residential greenness and myocardial injury biomarkers was stronger in men and older participants. Mediation analyses revealed that the effects of greenness on coronary stenosis, cTnI, CK, and CKMB were mediated by systolic blood pressure (SBP) and diastolic blood pressure (DBP).

CONCLUSION

Higher greenness exposure was associated with coronary artery stenosis and reduced levels of myocardial injury biomarkers, including cTnI, CK, and CKMB. These associations may be partially mediated by SBP and DBP levels.

The association between marathon running and high-sensitivity cardiac troponin: A systematic review and meta-analysis

BACKGROUND

Marathon running is an extreme sport with a distance of about 42 kilometers. Its relationship to high-sensitivity cardiac troponin (hs-cTn) remains controversial.

OBJECTIVE

As the gold standard for detecting myocardial injury, the trends of hs-cTn before and after a marathon were investigated and analyzed.

METHODS

A literature search was conducted in PubMed, EMBASE, and Cochrane Library databases by combing the keywords marathon and troponin, and studies regarding high-sensitivity cardiac troponin I (hs-cTnI) and high-sensitivity cardiac troponin T (hs-cTnT) concentrations before and after marathon running (not for half-marathon and ultra-marathon) were included. "Quality Assessment Tool for Before-After (Pre-Post) Studies With No Control Group" were used to assess the risk of bias. Statistical analysis was performed using Review Manager, presenting data as mean values and 95% confidence intervals (CIs). Sensitivity analysis and subgroup analysis were performed if there was high heterogeneity among studies based on I2 statistic.

RESULTS

A total of 13 studies involving 824 marathoners were included in this systematic review and meta-analysis. Both hs-cTnI (MD 68.79 ng/L, [95% CI 53.22, 84.37], p< 0.001) and hs-cTnT (MD 42.91 ng/L, [95% CI 30.39, 55.43], p< 0.001) were elevated after running a marathon, but the concentration of hs-cTnT returned to baseline after 72 to 96 h post-race (MD 0.11 ng/L, [95% CI -1.30, 1.52], p= 0.88). The results of subgroup analysis demonstrated that the 99th percentile upper reference limit of hs-cTnT might be the source of heterogeneity.

CONCLUSION

The concentrations of hs-cTnI and hs-cTnT were increased after marathon running, but the change of hs-cTnT is usually not seen as irreversible myocardial injury.

The pathophysiological and molecular mechanisms of atmospheric PM2.5 affecting cardiovascular health: A review

BACKGROUND

Exposure to ambient fine particulate matter (PM2.5, with aerodynamic diameter less than 2.5 µm) is a leading environmental risk factor for global cardiovascular health concern.

OBJECTIVE

To provide a roadmap for those new to this field, we reviewed the new insights into the pathophysiological and cellular/molecular mechanisms of PM2.5 responsible for cardiovascular health.

MAIN FINDINGS

PM2.5 is able to disrupt multiple physiological barriers integrity and translocate into the systemic circulation and get access to a range of secondary target organs. An ever-growing body of epidemiological and controlled exposure studies has evidenced a causal relationship between PM2.5 exposure and cardiovascular morbidity and mortality. A variety of cellular and molecular biology mechanisms responsible for the detrimental cardiovascular outcomes attributable to PM2.5 exposure have been described, including metabolic activation, oxidative stress, genotoxicity, inflammation, dysregulation of Ca2+ signaling, disturbance of autophagy, and induction of apoptosis, by which PM2.5 exposure impacts the functions and fates of multiple target cells in cardiovascular system or related organs and further alters a series of pathophysiological processes, such as cardiac autonomic nervous system imbalance, increasing blood pressure, metabolic disorder, accelerated atherosclerosis and plaque vulnerability, platelet aggregation and thrombosis, and disruption in cardiac structure and function, ultimately leading to cardiovascular events and death. Therein, oxidative stress and inflammation were suggested to play pivotal roles in those pathophysiological processes.

CONCLUSION

Those biology mechanisms have deepen insights into the etiology, course, prevention and treatment of this public health concern, although the underlying mechanisms have not yet been entirely clarified.

The Role of Fine Particles (PM 2.5) in the Genesis of Atherosclerosis and Myocardial Damage: Emphasis on Clinical and Epidemiological Data, and Pathophysiological Mechanisms

Due to the fact that atherosclerotic cardiovascular diseases (CVDs) dominate in the structure of morbidity, disability and mortality of the population, the study of the risk factors for the development of atherosclerotic CVDs, as well as the study of the underlying pathogenetic mechanisms thereof, is the most important area of scientific research in modern medicine. Understanding these aspects will allow to improve the set of treatment and preventive measures and activities. One of the important risk factors for the development of atherosclerosis, which has been actively studied recently, is air pollution with fine particulate matter (PM 2.5). According to clinical and epidemiological data, the level of air pollution with PM 2.5 exceeds the normative indicators in most regions of the world and is associated with subclinical markers of atherosclerosis and mortality from atherosclerotic CVDs. The aim of this article is to systematize and discuss in detail the role of PM 2.5 in the development of atherosclerosis and myocardial damage.

Polycyclic Aromatic Hydrocarbons (PAHs) Exposure Triggers Inflammation and Endothelial Dysfunction in BALB/c Mice: A Pilot Study

The particulate matter present in air pollution is a complex mixture of solid and liquid particles that vary in size, origin, and composition, among which are polycyclic aromatic hydrocarbons (PAHs). Although exposure to PAHs has become an important risk factor for cardiovascular disease, the mechanisms by which these compounds contribute to increased cardiovascular risk have not been fully explored. The aim of the present study was to evaluate the effects of PAH exposure on systemic pro-inflammatory cytokines and markers of endothelial dysfunction. An intervention was designed using a murine model composed of twenty BALB/c male mice separated into controls and three groups exposed to a mixture of phenanthrene, fluoranthene, and pyrene using three different concentrations. The serum levels of the inflammatory cytokines and gene expression of adhesion molecules located on endothelial cells along with inflammatory markers related to PAH exposure in aortic tissue were determined. Furthermore, the expression of the ICAM-1 and VCAM-1 proteins was evaluated. The data showed significant differences in IL-6 and IFN-γ in the serum. In the gene expression, significant differences for ICAM-1, VCAM-1, and E-Selectin were observed. The results suggest that phenanthrene, fluoranthene, and pyrene, present in air pollution, stimulate the increase in serum inflammatory cytokines and the expression of markers of endothelial dysfunction in the murine model studied, both relevant characteristics associated with the onset of disease atherosclerosis and cardiovascular disease.

Effect of Short-Term Exposure to Fine Particulate Matter and Particulate Matter Pollutants on Triggering Acute Myocardial Infarction and Acute Heart Failure

Long-term exposure to high concentrations of air pollution is known to lead to increased cardiovascular disease, but it remains unclear whether short-term exposure increases the incidence of acute myocardial infarction (AMI) and acute heart failure (AHF). A time-stratified case-crossover design was used, including data from the 2-year period (January 1, 2017 to December 31, 2018), from the National Health Insurance Academic Research Database of Taiwan. Air pollution data were obtained from the Air Quality Monitoring Station of the Environmental Protection Agency of the Executive Yuan. A generalized linear model was used for statistical analysis. In areas with a long-term moderate severity of air pollution, a 10 μg/m3 increase in fine particulate matter (PM2.5) and particulate matter (PM10) exposure in a short period of time coincided with an increase in AMI by 6.5% to 6.7% and 0.9% to 1.1%, respectively, and AHF by 6.1% to 6.4% and 0.9% to 1.0%, respectively. A long-term high severity of air pollution (PM2.5 and PM10) coincided with an increase in AMI by 7.9% to 8.8% and 4.4% to 4.9%, respectively, and AHF by 7.6% to 8.4% and 4.3% to 4.8%, respectively. In areas with a long-term moderate or high severity of air pollution, short-term exposure to high concentrations of PM2.5 and PM10 pollution is positively correlated with AMI and AHF.

Clustering of Environmental Parameters and the Risk of Acute Myocardial Infarction

The association between days with similar environmental parameters and cardiovascular events is unknown. We investigate the association between clusters of environmental parameters and acute myocardial infarction (AMI) risk in Singapore. Using k-means clustering and conditional Poisson models, we grouped calendar days from 2010 to 2015 based on rainfall, temperature, wind speed and the Pollutant Standards Index (PSI) and compared the incidence rate ratios (IRR) of AMI across the clusters using a time-stratified case-crossover design. Three distinct clusters were formed with Cluster 1 having high wind speed, Cluster 2 high rainfall, and Cluster 3 high temperature and PSI. Compared to Cluster 1, Cluster 3 had a higher AMI incidence with IRR 1.04 (95% confidence interval 1.01–1.07), but no significant difference was found between Cluster 1 and Cluster 2. Subgroup analyses showed that increased AMI incidence was significant only among those with age ≥65, male, non-smokers, non-ST elevation AMI (NSTEMI), history of hyperlipidemia and no history of ischemic heart disease, diabetes or hypertension. In conclusion, we found that AMI incidence, especially NSTEMI, is likely to be higher on days with high temperature and PSI. These findings have public health implications for AMI prevention and emergency health services delivery during the seasonal Southeast Asian transboundary haze.

Short-term exposure to traffic-related air pollution and STEMI events: Insights into STEMI onset and related cardiac impairment

AIMS

Evidence on the impacts of traffic-related air pollution (TRAP) on ST-segment elevation myocardial infarction (STEMI) events is limited. We aimed to assess the acute effects of TRAP exposure on the clinical onset of STEMI and related cardiac impairments.

METHODS AND RESULTS

We recruited patients who were admitted for STEMI and underwent primary percutaneous coronary intervention at Peking University Third Hospital between 2014 and 2020. Indicators relevant to cardiac impairments were measured. Concomitantly, hourly concentrations of traffic pollutants were monitored throughout the study period, including fine particulate matter, black carbon (BC), particles in size ranges of 5-560 nm, oxides of nitrogen (NO_X), nitrogen dioxide, and carbon monoxide. The mean (SD) age of participants was 62.4 (12.5) years. Daily average (range) concentrations of ambient BC and NO_X were 3.9 (0.1-25.0) μg/m³ and 90.8 (16.6-371.7) μg/m³. Significant increases in STEMI risks of 5.9% (95% CI: 0.1, 12.0) to 21.9% (95% CI: 6.0, 40.2) were associated with interquartile range increases in exposure to TRAP within a few hours. These changes were accompanied by significant elevations in cardiac troponin T levels of 6.9% (95% CI: 0.2, 14.1) to 41.7% (95% CI: 21.2, 65.6), as well as reductions in left ventricular ejection fraction of 1.5% (95% CI: 0.1, 2.9) to 3.7% (95% CI: 0.8, 6.4). Furthermore, the associations were attenuated in participants living in areas with higher residential greenness levels.

CONCLUSIONS

Our findings extend current understanding that short-term exposure to higher levels of traffic pollution was associated with increased STEMI risks and exacerbated cardiac impairments, and provide evidence on traffic pollution control priority for protecting vulnerable populations who are at greater risks of cardiovascular events.

Associations between short-term exposure to PM2.5 and cardiomyocyte injury in myocardial infarction survivors in North Carolina

Objective

Short-term ambient fine particulate matter (PM_2.5) is associated with adverse cardiovascular events including myocardial infarction (MI). However, few studies have examined associations between PM_2.5 and subclinical cardiomyocyte damage outside of overt cardiovascular events. Here we evaluate the impact of daily PM_2.5 on cardiac troponin I, a cardiomyocyte specific biomarker of cellular damage.

Methods

We conducted a retrospective cohort study of 2924 patients identified using electronic health records from the University of North Carolina Healthcare System who had a recorded MI between 2004 and 2016. Troponin I measurements were available from 2014 to 2016, and were required to be at least 1 week away from a clinically diagnosed MI. Daily ambient PM_2.5 concentrations were estimated at 1 km resolution and assigned to patient residence. Associations between log-transformed troponin I and daily PM_2.5 were evaluated using distributed lag linear mixed effects models adjusted for patient demographics, socioeconomic status and meteorology.

Results

A 10 µg/m³ elevation in PM_2.5 3 days before troponin I measurement was associated with 0.06 ng/mL higher troponin I (95% CI=0.004 to 0.12). In stratified models, this association was strongest in patients that were men, white and living in less urban areas. Similar associations were observed when using 2-day rolling averages and were consistently strongest when using the average exposure over the 5 days prior to troponin I measurement.

Conclusions

Daily elevations in PM_2.5 were associated with damage to cardiomyocytes, outside of the occurrence of an MI. Poor air quality may cause persistent damage to the cardiovascular system leading to increased risk of cardiovascular disease and adverse cardiovascular events.

Extracellular vesicles enclosed-miR-421 suppresses air pollution (PM2.5 )-induced cardiac dysfunction via ACE2 signalling

Air pollution, via ambient PM_2.5, is a big threat to public health since it associates with increased hospitalisation, incidence rate and  mortality of cardiopulmonary injury. However, the potential mediators of pulmonary injury in PM_2.5‐induced cardiovascular disorder are not fully understood. To investigate a potential cross talk between lung and heart upon PM_2.5 exposure, intratracheal instillation in vivo, organ culture ex vivo and human bronchial epithelial cells (Beas‐2B) culture in vitro experiments were performed respectively. The exposed supernatants of Beas‐2B were collected to treat primary neonatal rat cardiomyocytes (NRCMs). Upon intratracheal instillation, subacute PM_2.5 exposure caused cardiac dysfunction, which was time‐dependent secondary to lung injury in mice, thereby demonstrating a cross‐talk between lungs and heart potentially mediated via small extracellular vesicles (sEV). We isolated sEV from PM_2.5‐exposed mice serum and Beas‐2B supernatants to analyse the change of sEV subpopulations in response to PM_2.5. Single particle interferometric reflectance imaging sensing analysis (SP‐IRIS) demonstrated that PM_2.5 increased CD63/CD81/CD9 positive particles. Our results indicated that respiratory system‐derived sEV containing miR‐421 contributed to cardiac dysfunction post‐PM_2.5 exposure. Inhibition of miR‐421 by AAV9‐miR421‐sponge could significantly reverse PM_2.5‐induced cardiac dysfunction in mice. We identified that cardiac angiotensin converting enzyme 2 (ACE2) was a downstream target of sEV‐miR421, and induced myocardial cell apoptosis and cardiac dysfunction. In addition, we observed that GW4869 (an inhibitor of sEV release) or diminazene aceturate (DIZE, an activator of ACE2) treatment could attenuate PM_2.5‐induced cardiac dysfunction in vivo. Taken together, our results suggest that PM_2.5 exposure promotes sEV‐linked miR421 release after lung injury and hereby contributes to PM_2.5‐induced cardiac dysfunction via suppressing ACE2.

Exposure to black carbon is associated with symptoms of depression: A retrospective cohort study in college students

BACKGROUND

Previous studies have revealed a significant association of fine particulate matter (PM_2.5) with emotional disorders. However, as a crucial component of PM_2.5, little is known about the potential effect of exposure to black carbon (BC) on the symptoms of depression and anxiety.

OBJECTIVES

To explore the associations of long-term exposure to BC during the past six years with the current symptoms of depression and anxiety in a group of incoming college students.

METHODS

This was a retrospective cohort study of incoming students in five universities of China. Symptoms of depression and anxiety during the past two weeks were measured by the Patient Health Questionnaire-2 (PHQ-2) and Generalized Anxiety Disorder Scale-2 (GAD-2), respectively. Levels of BC and other environmental factors during 2013 ∼ 2018 (six years prior to the recruitment) was obtained from public repositories and linked to individual data by home addresses. Averagely daily dose of BC exposure was estimated according to the respiratory rate. Demographic and behavioral variables were collected through a questionnaire. The associations of BC with symptoms of depression and anxiety were estimated by mixed linear models adjusting for socioeconomic and behavioral characteristics, and the principal components of multiple environmental exposures. Subgroup analysis was conducted to assess the effect modification by covariates. Overall effect of environmental mixture was evaluated by weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR).

RESULTS

A total of 20,079 participants was included in the current study. After adjustment for covariates, long-term BC exposure was significantly associated with symptoms of depression (β = 0.17, P < 0.001) but not anxiety (β = 0.07, P = 0.125). Effect modification by sex and parental educational level: BC was correlated with depressive symptoms in women (β = 0.23, P < 0.001) but not in men (β = 0.04, P = 0.581), and higher educational level was associated with decreased effect sizes of BC. Sensitivity analysis showed that the acute and short-term effects of BC on depression was consistent with its long-term exposure (β varied from 0.18 to 0.20). WQS identified BC as the primary pollutant in association with symptoms of depression but not anxiety. BKMR identified no significant interaction between BC and other exposures.

CONCLUSION

Exposure to BC is associated with symptoms of depression but not anxiety in college students, and the relationship is modified by sex and education.