Air pollution, genetic susceptibility, and the risk of atrial fibrillation: A large prospective cohort study

Burden of Atrial Fibrillation and Atrial Flutter From 1990 to 2021 in China: Global Burden of Disease Study 2021 Update

BACKGROUND

Atrial fibrillation (AF) and atrial flutter (AFL) represent increasingly significant health burden globally. We aimed to systematically evaluate the status and trends of AF/AFL burden and attributable risk factors in China.

METHODS

We assessed the burden of AF/AFL measured as prevalence, incidence, mortality, and disability-adjusted life years (DALYs), by sex and age groups in China based on the Global Burden of Diseases Study (GBD) 2021 project.

RESULTS

In China, there were 10,775.72 thousand AF/AFL prevalent cases, 916.18 thousand AF/AFL incident cases, and 64.73 thousand AF/AFL mortality cases, contributing to 1653.12 thousand DALYs due to AF/AFL in 2021. Trend analysis indicated that the AAPC of number and crude rates of prevalence, incidence, mortality, and DALYs all escalated from 1990 to 2021. The current AF/AFL burden and temporal trend between 1990 and 2021 displayed heterogeneity based on sex and age groups. The spectrum for risk factors attributed for DALYs due to AF/AFL presented sex- and age-specific manifestation. High systolic blood pressure served as the emerging leading contributor to DALYs due to AF/AFL in China.

CONCLUSION

A significant increase in the burden of AF/AFL underscores the enduring public health burden of AF/AFL in China, marked by profound sex and age-related variations. There is a pressing imperative to adopt tailored strategies to attenuate increasing burden of AF/AFL and combat alongside high complication burden due to AF/AFL in China.

Long-Term Exposure to PM2.5 Constituents, Genetic Susceptibility, and Incident Dementia: A Prospective Cohort Study among 0.2 Million Older Adults

Fine particulate matter, known as PM2.5, is recognized as a risk factor for dementia. However, the specific linkage between PM2.5 constituents and dementia is not well understood. We conducted a cohort of 217,336 participants of the UK Biobank to explore the association of long-term exposure to PM2.5 constituents with all-cause dementia, Alzheimer's disease (AD), and vascular dementia. We estimated PM2.5 constituents based on residential addresses by an evaluation model and used time-varying Cox models and Quantile g-computation models to assess the effects of individual constituents and their mixtures. Genetic susceptibility to dementia was assessed using a polygenic risk score, and its multiplicative and additive interactions with PM2.5 constituents were analyzed. Our results showed that black carbon (BC), ammonium (NH4+), organic matter (OM), and sulfate (SO42-) were positively associated with all-cause dementia, while BC and OM were linked to AD, with BC being the most influential. The combined effect of PM2.5 constituents and genetic risk was stronger than their individual effect. This study offers new insights into the association between PM2.5 constituents and dementia, especially those from fuel combustion and automobile exhaust, and highlights the need for effective prevention strategies.

Ambient air pollution does not diminish the beneficial effects of active commuting on heart failure: a prospective study in UK Biobank

BACKGROUND

Evidence on active commuting and heart failure (HF) under levels of air pollution exposure is limited, and little is known on the potential mediation roles of inflammation. The objective of this study was to investigate the association between active commuting and HF, as well as to ascertain whether air pollution may influence this relationship.

METHODS

This prospective study included 241,786 participants without HF at baseline in UK Biobank. The commuting mode was recorded using questionnaire. We examined long-term exposure to air pollution, including particulate matter with an aerodynamic diameter smaller than 2.5 μm (PM2.5) or 10 μm (PM10), PM2.5-10, nitrogen dioxide (NO2), and nitrogen oxide (NOx). The incident HF was identified through linkages with medical records. Cox proportional hazard models were used to estimate the association of active commuting on HF under different air pollution concentrations. Furthermore, mediation analysis was performed to test the mediated role of inflammation.

RESULTS

A median follow-up period of 13.7 years yielded 4485 incident cases of HF. Compared with non-active commuting, both cycling (HR = 0.66, 95%CI: 0.57-0.76) and walking mode (HR = 0.86, 95%CI: 0.78-0.94) were found to be associated with the reduced risk of HF, following the full adjustment for covariates, including PM2.5. The beneficial effect of cycling (HR = 0.68, 95%CI: 0.56-0.81) and walking mode (HR = 0.82, 95%CI: 0.72-0.92) on HF was also observed in the context of high PM2.5 exposure. The inflammatory response was responsible for mediating 21.97% and 13.83% of the effect of the association between cycling mode and walking mode and HF.

CONCLUSIONS

For those residing in regions with relatively elevated air pollution levels, active commuting may still be a viable strategy for the prevention of HF.

Air Pollution, Genetic Susceptibility, and the Risk of Ventricular Arrhythmias: A prospective cohort study in the UK Biobank

AIMS

Both genetic and environmental factors contribute to the development of ventricular arrhythmias (VAs). However, the extent to which genetic susceptibility modifies the effects of air pollutants on the risk of VAs remains poorly understood.

METHODS

This study included 491,305 participants without VAs at baseline from UK Biobank. Exposure to ambient air pollutants, including particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2) and nitrogen oxides (NOX), was estimated through land use regression modelling. The associations between air pollutants and the incidence of VAs were then investigated using a Cox proportional hazards model adjusted for covariates. Additionally, we established a polygenic risk score (PRS) for VAs and assessed the joint effect of genetic susceptibility and air pollution on incident VAs.

RESULTS

During a median follow-up of 14.3 years, 4,333 participants were diagnosed with VAs. Increased long-term exposure to PM2.5, PM10, NO2 and NOx was significantly associated with higher risks of VAs, with hazard ratios (HR) per quintile increase of 1.07 (95% confidence interval, 95% CI: 1.03-1.11), 1.07 (1.03-1.11), 1.10 (1.06-1.14) and 1.08 (1.05-1.12) for each pollutant respectively. Notably, there were significant additive interactions between air pollutants and genetic risk. Participants with both high genetic risk and high exposure to air pollution exhibited the greatest risk of VAs, with the highest HRs observed for PM2.5 (HR, 4.51; 95% CI, 3.66-5.56), PM10 (HR, 4.28; 95% CI, 3.52-5.22), NO2 (HR, 4.90; 95% CI, 3.97-6.03), and NOx (HR, 4.56; 95% CI, 3.72-5.60), respectively.

CONCLUSIONS

Long-term exposure to air pollution is associated with an increased risk of VAs, especially in individuals with a high genetic risk.

A Breath of Trouble: Unraveling the Impact of Air Pollution on Atrial Fibrillation

Air pollution is a pervasive global challenge with profound implications for public health. This review explores the intricate relationship between air pollution and atrial fibrillation (AF), a prevalent cardiac arrhythmia associated with significant morbidity and mortality. Drawing on a comprehensive analysis of the existing literature, this review synthesizes current evidence linking various air pollutants, including particulate matter, nitrogen dioxide, ozone, and carbon monoxide, to the development and exacerbation of AF. The review delves into the role of air pollution as a global health issue alongside its specific sources, such as traffic-related emissions and industrial pollutants. It also examines the underlying mechanisms through which air pollution may contribute to the pathogenesis of AF, encompassing oxidative stress, inflammation, and autonomic nervous system dysregulation. In addition, it explores the impact of individual pollutants and the results of meta-analyses. It considers the results of vulnerable populations, including sex differences between the individuals and those with pre-existing cardiovascular conditions, who may be disproportionately affected. We also address critical research gaps in this area. Overall, air pollution has been increasingly recognized as a significant trigger for AF, with evidence linking exposure to particulate matter and gaseous pollutants to an increased incidence in short- as well as long-term exposure, highlighting the need for targeted public health interventions and further research to mitigate its cardiovascular impact.

Noise Exposure in the Workplace, Genetic Susceptibility, and Incidence of Atrial Fibrillation: A Prospective Cohort Study

BACKGROUND

No study explored the association of noise exposure in the workplace and genetic susceptibility with incidence of atrial fibrillation (AF). We aimed to assess the separate and joint relationship of noise exposure in the workplace and genetic susceptibility with the risk of AF.

METHODS AND RESULTS

We included 167 577 participants without AF at baseline in UK Biobank. Cox proportional hazards models were used to assess the separate and joint association of noise exposure in the workplace and genetic susceptibility with the risk of AF. During a median follow-up of 11.83 years, we observed 9355 AF cases. Compared with no noise exposure in the workplace, the hazard ratios (HRs) and were 1.08 (95% CI, 0.99-1.18) for noise exposure in the workplace of <1 year, 1.03 (95% CI, 0.95-1.12) for noise exposure in the workplace of around 1 to 5 years, and 1.08 (95% CI, 1.02-1.14) for noise exposure in the workplace of >5 years, respectively, after adjusting for potential confounders. Genetic risk was positively associated with AF, compared with low genetic risk (tertile 1), the HRs were 1.50 (95% CI, 1.41-1.59) for medium genetic risk (tertile 2) and 2.51 (95% CI, 2.38-2.65) for high genetic risk (tertile 3). However, no interaction between noise exposure in the workplace and genetic susceptibility was observed (P>0.05).

CONCLUSIONS

Long-term noise exposure in the workplace is positively associated with a higher incidence of AF regardless of genetic background.

Long-term exposure to fine particulate matter constituents, genetic susceptibility, and incident heart failure among 411 807 adults

AIMS

Long-term fine particulate matter (PM2.5) exposure has been linked to incident heart failure (HF), but the impacts of its constituents remain unknown. We aimed to investigate the associations of PM2.5 constituents with incident HF, and further evaluate the modification effects of genetic susceptibility.

METHODS AND RESULTS

PM2.5 and its constituents, including elemental carbon (EC), organic matter (OM), ammonium (NH4 +), nitrate (NO3 -), and sulfate (SO4 2-), were estimated using the European Monitoring and Evaluation Programme model applied to the UK (EMEP4UK) driven by Weather and Research Forecast model meteorology. A polygenic risk score (PRS) was calculated to represent genetic susceptibility to HF. We employed Cox models to evaluate the associations of PM2.5 constituents with incident HF. Quantile-based g-computation model was used to identify the main contributor of PM2.5 constituents. Among 411 807 individuals in the UK Biobank, 7554 participants developed HF during a median follow-up of 12.05 years. The adjusted hazard ratios of HF for each interquartile range increase in PM2.5, EC, OM, NH4 +, NO3 -, and SO4 2- were 1.50 (1.46-1.54), 1.31 (1.27-1.34), 1.12 (1.09-1.15), 1.42 (1.41-1.44), 1.26 (1.23-1.29), and 1.25 (1.24-1.26), respectively. EC (43%) played the most important role, followed by NH4 + and SO4 2-. Moreover, synergistic additive interactions accounted for 9-16% of the HF events in individuals exposed to both PM2.5, NH4 +, NO3 -, and SO4 2- and PRS.

CONCLUSION

Long-term exposure to PM2.5 constituents may elevate HF risk, and EC was the major contributor. Additive effects of PM2.5 constituents and PRS on HF risk were revealed.

Joint effects of air pollution and genetic susceptibility on incident primary open-angle glaucoma

BACKGROUND

Air pollutants are important exogenous stimulants to eye diseases, but knowledge of associations between long-term exposure to air pollutants and the risk of primary open-angle glaucoma (POAG) is limited. This study aimed to determine whether long-term exposure to air pollutants, genetic susceptibility, and their joint effects lead to an elevated risk of incident POAG.

METHODS

This is a population-based prospective cohort study from UK Biobank participants with complete measures of air pollution exposure and polygenetic risk scores. Cox proportional hazard models were fitted to assess the individual and joint effects of long-term exposure to air pollutants and genetics on the risk of POAG. In addition, the effect modification of genetic susceptibility was examined on an additive or multiplicative scale.

RESULTS

Among 434,290 participants with a mean (SD) age of 56.5 (8.1) years, 6651 (1.53 %) were diagnosed with POAG during a median follow-up of 13.7 years. Long-term exposure to air pollutants was associated with an increased risk of POAG. The hazard ratios associated with per interquartile range increase in PM2.5, PM2.5 absorbance, PM10, NO2, and NOX individually ranged from 1.027 (95 % CI: 1.001-1.054) to 1.067 (95 % CI: 1.035-1.099). Compared with individuals residing in low-pollution areas and having low polygenic risk scores, the risk of incident POAG increased by 105.5 % (95 % CI: 78.3 %-136.9 %), 79.7 % (95 % CI: 56.5 %-106.5 %), 103.2 % (95 % CI: 76.9 %-133.4 %), 89.4 % (95 % CI: 63.9 %-118.9 %), and 90.2 % (95 % CI: 64.8 %-119.5 %) among those simultaneously exposed to high air pollutants levels and high genetic risk, respectively. Genetic susceptibility interacted with PM2.5 absorbance and NO2 in an additive manner, while no evidence of multiplicative interaction was found in this study. Stratification analyses revealed stronger effects in Black people and the elderly.

CONCLUSION

Long-term air pollutant exposure was associated with an increased risk of POAG incidence, particularly in the population with high genetic predisposition.

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.

Air pollution, greenspace exposure and risk of Parkinson's disease: a prospective study of 441,462 participants

BACKGROUND

The current understandings of the relationship between air pollution (AP), greenspace exposure and Parkinson's Disease (PD) remain inconclusive.

METHODS

We engaged 441,462 participants from the UK Biobank who were not diagnosed with PD. Utilizing Cox proportional hazard regression model, relationships between AP [nitrogen dioxide (NO2), and nitrogen oxides (NOX), particulate matter < 2.5 μm in aerodynamic diameter(PM2.5), coarse particulate matter between 2.5 μm and 10 μm in aerodynamic diameter(PM2.5-10), particulate matter < 10 μm in aerodynamic diameter(PM10)], greenspace exposure, and PD risk were determined independently. Our analyses comprised three models, adjusted for covariates, and affirmed through six sensitivity analyses to bolster the robustness of our findings. Moreover, mediation analysis was deployed to discern the mediating effect of AP between greenspaces and PD.

RESULTS

During a median follow-up of 12.23 years (5,574,293 person-years), there were 3,293 PD events. Each interquartile (IQR) increment in NO2 and PM10 concentrations were associated with 10% and 8% increase in PD onset risk, while the increases in NOX, PM2.5 and PM2.5-10 were not associated with PD risk. Additionally, greenspace may safeguard by reducing NO2 and PM10 levels, with the effect mediated by NO2 and PM10 in greenspace-PD relationship.

CONCLUSION

Our findings indicate that an IQR increase in ambient NO2 and PM10 concentrations was associated with risk of PD development, while other pollutants (NOX, PM2.5 and PM2.5-10) were not associated with PD risk. Firstly, we find that augmented exposure to greenspace was associated with the lower PD risk by reducing NO2 and PM10 levels.

Potential Early Effect Biomarkers for Ambient Air Pollution Related Mental Disorders

Air pollution is one of the greatest environmental risks to health, with 99% of the world's population living where the World Health Organization's air quality guidelines were not met. In addition to the respiratory and cardiovascular systems, the brain is another potential target of air pollution. Population- and experiment-based studies have shown that air pollution may affect mental health through direct or indirect biological pathways. The evidence for mental hazards associated with air pollution has been well documented. However, previous reviews mainly focused on epidemiological associations of air pollution with some specific mental disorders or possible biological mechanisms. A systematic review is absent for early effect biomarkers for characterizing mental health hazards associated with ambient air pollution, which can be used for early warning of related mental disorders and identifying susceptible populations at high risk. This review summarizes possible biomarkers involved in oxidative stress, inflammation, and epigenetic changes linking air pollution and mental disorders, as well as genetic susceptibility biomarkers. These biomarkers may provide a better understanding of air pollution's adverse effects on mental disorders and provide future research direction in this arena.

Fibrinaloid Microclots and Atrial Fibrillation

Atrial fibrillation (AF) is a comorbidity of a variety of other chronic, inflammatory diseases for which fibrinaloid microclots are a known accompaniment (and in some cases, a cause, with a mechanistic basis). Clots are, of course, a well-known consequence of atrial fibrillation. We here ask the question whether the fibrinaloid microclots seen in plasma or serum may in fact also be a cause of (or contributor to) the development of AF. We consider known 'risk factors' for AF, and in particular, exogenous stimuli such as infection and air pollution by particulates, both of which are known to cause AF. The external accompaniments of both bacterial (lipopolysaccharide and lipoteichoic acids) and viral (SARS-CoV-2 spike protein) infections are known to stimulate fibrinaloid microclots when added in vitro, and fibrinaloid microclots, as with other amyloid proteins, can be cytotoxic, both by inducing hypoxia/reperfusion and by other means. Strokes and thromboembolisms are also common consequences of AF. Consequently, taking a systems approach, we review the considerable evidence in detail, which leads us to suggest that it is likely that microclots may well have an aetiological role in the development of AF. This has significant mechanistic and therapeutic implications.

Environmental Exposome and Atrial Fibrillation: Emerging Evidence and Future Directions

There has been increased awareness of the linkage between environmental exposures and cardiovascular health and disease. Atrial fibrillation is the most common sustained cardiac arrhythmia, affecting millions of people worldwide and contributing to substantial morbidity and mortality. Although numerous studies have explored the role of genetic and lifestyle factors in the development and progression of atrial fibrillation, the potential impact of environmental determinants on this prevalent condition has received comparatively less attention. This review aims to provide a comprehensive overview of the current evidence on environmental determinants of atrial fibrillation, encompassing factors such as air pollution, temperature, humidity, and other meteorologic conditions, noise pollution, greenspace, and the social environment. We discuss the existing evidence from epidemiological and mechanistic studies, critically evaluating the strengths and limitations of these investigations and the potential underlying biological mechanisms through which environmental exposures may affect atrial fibrillation risk. Furthermore, we address the potential implications of these findings for public health and clinical practice and identify knowledge gaps and future research directions in this emerging field.

Genetic susceptibility modifies the association of long-term air pollution exposure on Parkinson's disease

Inconsistent findings exist regarding the potential association between polluted air and Parkinson's disease (PD), with unclear insights into the role of inherited sensitivity. This study sought to explore the potential link between various air pollutants and PD risk, investigating whether genetic susceptibility modulates these associations. The population-based study involved 312,009 initially PD-free participants with complete genotyping data. Annual mean concentrations of PM2.5, PM10, NO2, and NOx were estimated, and a polygenic risk score (PRS) was computed to assess individual genetic risks for PD. Cox proportional risk models were employed to calculate hazard ratios (HR) and 95% confidence intervals (CI) for the associations between ambient air pollutants, genetic risk, and incident PD. Over a median 12.07-year follow-up, 2356 PD cases (0.76%) were observed. Compared to the lowest quartile of air pollution, the highest quartiles of NO2 and PM10 pollution showed HRs and 95% CIs of 1.247 (1.089-1.427) and 1.201 (1.052-1.373) for PD incidence, respectively. Each 10 μg/m3 increase in NO2 and PM10 yielded elevated HRs and 95% CIs for PD of 1.089 (1.026-1.155) and 1.363 (1.043-1.782), respectively. Individuals with significant genetic and PM10 exposure risks had the highest PD development risk (HR: 2.748, 95% CI: 2.145-3.520). Similarly, those with substantial genetic and NO2 exposure risks were over twice as likely to develop PD compared to minimal-risk counterparts (HR: 2.414, 95% CI: 1.912-3.048). Findings suggest that exposure to air contaminants heightens PD risk, particularly in individuals genetically predisposed to high susceptibility.