Aircraft noise exposure induces pro-inflammatory vascular conditioning and amplifies vascular dysfunction and impairment of cardiac function after myocardial infarction

Short-term aircraft noise stress induces a fundamental metabolic shift in heart proteome and metabolome that bears the hallmarks of cardiovascular disease

Environmental stressors in the modern world can fundamentally affect human physiology and health. Exposure to stressors like air pollution, heat, and traffic noise has been linked to a pronounced increase in non-communicable diseases. Specifically, aircraft noise has been identified as a risk factor for cardiovascular and metabolic diseases, such as arteriosclerosis, heart failure, stroke, and diabetes. Noise stress leads to neuronal activation with subsequent stress hormone release that ultimately activates the renin-angiotensin-aldosterone system, increases inflammation and oxidative stress thus substantially affecting the cardiovascular system. However, despite the epidemiological evidence of a link between noise stress and metabolic dysfunction, the consequences of exposure at the molecular, metabolic level of the cardiovascular system are largely unknown. Here, we use a murine model system of short-term aircraft noise exposure to show that noise stress profoundly alters heart metabolism. Within 4 days of noise exposure, the heart proteome and metabolome bear the hallmarks of reduced potential for generating ATP from fatty-acid beta-oxidation, the tricarboxylic acid cycle, and the electron transport chain. This is accompanied by the increased expression of glycolytic metabolites, including the end-product, lactate, suggesting a compensatory shift of energy production towards anaerobic glycolysis. Intriguingly, the metabolic shift is reminiscent of what is observed in failing and ischaemic hearts. Mechanistically, we further show that the metabolic rewiring is likely driven by reactive oxygen species (ROS), as we can rescue the phenotype by knocking out NOX-2/gp91phox, a ROS inducer, in mice. Our results suggest that within a short exposure time, the cardiovascular system undergoes a fundamental metabolic shift that bears the hallmarks of cardiovascular disease. These findings underscore the urgent need to comprehend the molecular consequences of environmental stressors, paving the way for targeted interventions to mitigate health risks associated with chronic noise exposure in modern, environments heavily disturbed by noise pollution.

Effects of Long-Term Airport Noise Exposure on Inflammation and Intestinal Flora and Their Metabolites in Mice

Background: The World Health Organization has indicated that airport noise is strongly associated with cardiovascular disease, with vascular inflammation identified as the primary mechanism. Therefore, long-term exposure to airport noise is considered far more harmful than other types of noise. However, there remains a lack of research into the mechanisms underlying long-term exposure to airport noise and harm to the human body. Methods: A mouse model was established and exposed to airport noise at a maximum sound pressure level of 95 dB(A) and an equivalent continuous sound pressure level of 72 dB(A) for 12 h per day over a period of 100 days. Quantitative polymerase chain reaction (qPCR) was used to detect the mRNA expression levels of pro-inflammatory and anti-inflammatory factors. Enzyme-linked immunosorbent assay (ELISA) was used to detect LPS, LTA, TMA, and TMAO levels. Intestinal flora composition was analyzed by 16S rDNA sequencing, and targeted metabolomics was employed to determine the levels of serum short-chain fatty acids. Results: Long-term airport noise exposure significantly increased systolic blood pressure, diastolic blood pressure, and mean blood pressure (p < 0.05); significantly increased the mRNA expression levels of oxidative stress parameters (nuclear matrix protein 2, 3-nitrotyrosine, and monocyte chemoattractant protein-1) (p < 0.05); significantly increased pro-inflammatory factors (interleukin 6 and tumor necrosis factor alpha) (p < 0.05); significantly decreased the mRNA expression level of anti-inflammatory factor interleukin 10 (p < 0.05); and significantly increased the content of LPS and LTA (p < 0.05). The composition of the main flora in the intestinal tract was structurally disordered, and there were significant differences between the noise-exposed and control groups at the levels of the phylum, family, and genus of bacteria. β-diversity of the principal component analysis diagrams was clearly distinguished. Compared with those of the control group, TMA-producing bacteria and levels of TMA and TMAO were significantly reduced, and the serum ethanoic acid and propanoic acid levels of the noise-exposed group were significantly decreased (p < 0.05). Conclusions: Long-term airport noise exposure causes significant elevation of blood pressure and structural disruption in the composition of the intestinal flora in mice, leading to elevated levels of oxidative stress and inflammation, resulting in metabolic disorders that lead to significant changes in the production of metabolites.

Transportation noise and the cardiometabolic risk

Transportation noise is a widespread and often underestimated environmental pollutant, posing a substantial health risk particularly in urban areas. In contrast to air pollution, the health effects of noise pollution are less extensively documented. Defined as an unwanted and/or harmful sound, noise pollution affects over 20 % of the European Union (EU) population, contributing to an estimated 12,000 premature deaths and 48,000 new cases of ischemic heart disease annually. Recent epidemiological evidence strengthens the link between transportation noise and cardiovascular disease (CVD). A 2024 Umbrella + review with subsequent meta-analyses found that road traffic noise was associated with risk of CVD, more specifically a 4.1 % higher risk for ischemic heart disease, 4.6 % for stroke, and 4.4 % for heart failure per 10 dB(A). Translational and experimental studies have investigated the biological mechanisms behind noise-induced cardiovascular damage, showing that noise impacts stress and sleep pathways. Human studies reveal that nighttime noise impairs vascular function, elevates stress hormone levels, and triggers inflammation and oxidative stress, particularly in individuals with pre-existing CVD. Animal research corroborates these findings, demonstrating that noise exposure leads to endothelial dysfunction, elevated blood pressure, and oxidative stress through mechanisms shared with traditional cardiovascular risk factors. Mitigation strategies are crucial to reducing the health impacts of environmental noise. For road traffic, transitioning to electric vehicles offers minimal noise reduction, necessitating measures such as noise-reducing asphalt, low-noise tyres, and changes in urban infrastructure, whereas for aircraft noise nighttime flight bans and optimized flight paths are important tools for reducing noise exposure. Addressing co-exposure to noise and air pollution is essential for a comprehensive approach to mitigating the environmental burden on cardiovascular health.

Exposure to aircraft noise exacerbates cardiovascular and oxidative damage in three mouse models of diabetes

AIMS

Epidemiology links noise to increased risk of metabolic diseases like diabetes and obesity. Translational studies in humans and experimental animals showed that noise causes reactive oxygen species (ROS)-mediated cardiovascular damage. The interaction between noise and diabetes, specifically potential additive adverse effects, remains to be determined.

METHODS AND RESULTS

C57BL/6 mice were treated with streptozotocin (i.p. injections, 50 mg/kg/day for 5 days) to induce type 1 diabetes mellitus, with S961 (subcutaneous osmotic mini-pumps, 0.57 mg/kg/day for 7 days) or fed a high-fat diet (HFD, 20 weeks) to induce type 2 diabetes mellitus. Control and diabetic mice were exposed to aircraft noise to an average sound pressure level of 72 dB(A) for 4 days. While body weight was unaffected, noise reduced insulin production in all diabetes models. The oral glucose tolerance test showed only an additive aggravation by noise in the HFD model. Noise increased blood pressure and aggravated diabetes-induced aortic, mesenteric, and cerebral arterioles' endothelial dysfunction. ROS formation in cerebral arterioles, the aorta, the heart, and isolated mitochondria was consistently increased by noise in all models of diabetes. Mitochondrial respiration was impaired by diabetes and noise, however without additive effects. Noise increased ROS and caused inflammation in adipose tissue in the HFD model. RNA-sequencing data and alteration of gene pathway clusters also supported additive damage by noise in the setting of diabetes.

CONCLUSION

In all three models of diabetes, aircraft noise exacerbates oxidative stress, inflammation, and endothelial dysfunction in mice with pre-existing diabetes. Thus, noise may potentiate the already increased cardiovascular risk in diabetic patients.

The Influence of Noise Exposure on Cognitive Function in Children and Adolescents: A Meta-Analysis

Environmental noise has been repeatedly linked to negative effects on cognitive functioning among children and adolescents. This research sought to systematically assess studies investigating the relationship between noise exposure and cognitive outcomes in young individuals. Through a meta-analysis of eight primary studies published between 2001 and 2023, this study examined the effects of various noise types on cognitive performance across multiple domains in young populations. The findings reveal that noise exposure significantly impairs cognitive performance in children and adolescents, with a standardized mean difference (SMD) of -0.544 (95% CI: [-0.616, -0.472]), z = -14.85, p < 0.0001. These results underscore the profound impact of environmental noise on cognitive functioning in younger populations.

CD40-TRAF6 inhibition suppresses cardiovascular inflammation, oxidative stress and functional complications in a mouse model of arterial hypertension

Cardiovascular disease is the leading cause of disease burden and death worldwide and is fueled by vascular inflammation. CD40L-CD40-TRAF signaling is involved in the progression of atherosclerosis and drives the development of coronary heart disease (CHD). The present study investigates whether the CD40L-CD40-TRAF6 signaling pathway with focus on immune cells and adipocytes could be a therapeutic target in arterial hypertension. Arterial hypertension was induced in WT (C57BL6/J) and cell-specific CD40(L) knockout mice (AdipoqCre x CD40 fl/fl, CD4Cre x CD40 fl/fl, CD19Cre x CD40 fl/fl, and GP1baCre x CD40L fl/fl) via angiotensin (AT-II) infusion (1 mg/kg/d) for seven days. Hypertensive WT mice were also treated with a CD40-TRAF6 inhibitor (2.5 mg/kg/d, for 7d). The TRAF6 inhibitor treatment normalized endothelial dysfunction and reduced blood pressure in hypertensive wild type animals. Reactive oxygen species production was decreased by TRAF6 inhibition in blood, aorta, heart, kidney, and perivascular fat tissue. Additionally, FACS analysis revealed that TRAF6 inhibition prevents immune cell migration into the aortic vessel wall observed by reduced CD45+ leukocyte, Ly6G+/Ly6C+ neutrophil, and Ly6Chigh inflammatory monocyte content. The hypertensive cell type-specific CD40(L) knockout animals showed only a minor effect on endothelial function, blood pressure, and oxidative stress. Therefore, we conclude that targeting CD40 directly on adipocytes, B-cells, T-cells, or CD40L on platelets is not a promising target to prevent hypertension complications. In summary, TRAF6 inhibition but not adipocyte, B-cell, or T-cell-specific CD40 or platelet-specific CD40L deficiency reduces pathophysiological vascular inflammation in hypertensive mice, suggesting TRAF6 inhibition as a potential therapeutic target in hypertensive patients.

Investigating the effect of occupational noise exposure in the risk of atrial fibrillation: a case study among Chinese occupational populations

PURPOSE

This study examines the link between high occupational noise exposure and atrial fibrillation (AF), given the limited existing evidence.

METHODS

We conducted a cross-sectional study among participants from a large heavy industry enterprise in China. High noise exposure was defined as an equivalent A-weighted sound level (LAeq, 8 h) of ≥ 80 dB(A) during an 8 h workday. Statistical analyses included univariate analysis to assess relationships between high noise exposure, cardiovascular risk factors, and AF. Mediation analysis identified potential mediators between high noise exposure and AF. Propensity score matching (PSM) and multivariable analysis were used to evaluate the independent association between high noise exposure and AF.

RESULTS

A total of 4530 participants were included, with 1526 experiencing high noise exposure, and 167 diagnosed with AF. Adjusted mediation analysis revealed that sleep disorders, hypertension, dyslipidemia, and dietary quality were the primary mediators for AF among those exposed to high noise, accounting for 12.4%, 9.6%, 8.9%, and 6.7% of the effect, respectively. PSM analysis showed a significantly higher proportion of AF in individuals with high noise exposure compared to those with low exposure (5.4% vs. 3.0%, P = 0.003). Multivariable analysis indicated that the risk of AF was doubled in individuals with high noise exposure (OR = 1.99, 95% CI 1.38-2.88, P < 0.001).

CONCLUSION

High occupational noise exposure increases the risk of AF in the working population, acting both as an independent risk factor and through mediation effects. Sleep disorders, hypertension, dyslipidemia, and dietary quality are the main mediators. These findings highlight the importance of integrating noise control with cardiovascular health management in workplace safety policies to prevent AF among industrial workers.

TRIAL REGISTRATION NUMBER

ChiCTR2300077951, registered on November 24, 2023, in the Chinese Clinical Trial Registry.

Network Toxicology Analysis Reveals Molecular Mechanisms Associated with Noise Exposure to Multiple Diseases

Noise pollution is recognized as an environmental stressor that affects various biological processes beyond auditory functions, mainly through stress hormones release. This work explored the biological processes, diseases attributable to noise-regulated targets, and the main targets involved in each disease, employing a network toxicology approach. Through various databases and bioinformatics analysis, a total of 577 targets were identified as potential candidates implicated in diseases related to noise exposure, 10 from the GEO database and the rest from other databases. Noise pollution was found to regulate processes such as hormone response, cellular response to cytokines, and circulatory system functions, contributing to the development of the pathological manifestations related to the diseases like hypertension, ischemia, atherosclerosis, and cirrhosis. Hub targets for ischemia included IL-6, CASP3, AKT1, and TNF-α, while NOS3 was related to hypertension, and NOS3, TNF-α, AGT, and IL-1B to atherosclerosis. The targets were found to be linked to vascular regulation and inflammation in cardio- and cerebrovascular diseases. Molecular docking studies indicated stress hormones released by noise exposure regulates these diseases through signaling pathways, without implicating its direct binding to hub targets. The results indicate that individuals with vascular diseases are more vulnerable to the effects of prolonged noise exposure.

Community impacts of aviation noise: a pilot survey

BACKGROUND

Aviation noise policy in the United States is decades old and has not kept up with the science on the adverse effects of chronic noise exposure. New aviation noise policies are needed for the 21st century, respecting the lived experience of affected communities. Existing surveys have reported adverse impacts from aviation noise but more information is needed to understand the factors that contribute to those impacts.

OBJECTIVE

To evaluate the impacts of current aircraft noise exposure on impacted communities and their determinants.

METHODS

A 10-question online community pilot survey was distributed in May 2022 to an email list of groups and individuals in aviation-impacted communities. The survey was open for two weeks. Information on geographic location, frequency of exposure, and type of aircraft exposure were collected. Seven questions focused on the type and magnitude of health impacts, perceptions, and concerns.

RESULTS

A total of 1452 surveys were completed within the 2-week period. Respondents report experiencing loud, repetitive, low-altitude aircraft noise - day and night - causing stress and negative effects on mental and physical health. For many, "annoyance" did not adequately describe their experience. Strong, consistent exposure-response patterns for weekly flight frequency (<100 to >1000 flights) were found for most health impacts, perceptions, and concerns. The likelihood of adverse impacts and heightened perceptions and concerns was greatest in respondents exposed mainly to military aircraft.

SIGNIFICANCE

Current aviation noise policy is based on annoyance, and relies on a metric that exceeds safe levels and does not meaningfully convey community impact. Aviation-impacted communities are experiencing mental and physical health impacts that extend beyond annoyance. The magnitude of impact is influenced by flight frequency and aircraft type. Aviation noise policy should be updated to account for those factors and focus on reducing public health impacts and their human and economic costs.

IMPACT STATEMENT

Aviation noise policy in the United States is decades old and is based solely on the concept of annoyance without sufficient regard to the harms caused to health and well-being of people living in aviation-impacted communities. Efforts to amend the policy must be informed by the scientific evidence on the adverse effects of noise and health and by metrics that properly represent the lived experiences of communities. The results of this pilot survey highlight the importance of incorporating these aspects into policy for preventing and mitigating harms caused by aviation noise, especially as the industry grows.

Noise causes cardiovascular disease: it's time to act

BACKGROUND

Chronic transportation noise is an environmental stressor affecting a substantial portion of the population. The World Health Organization (WHO) and various studies have established associations between transportation noise and cardiovascular disease (CVD), such as myocardial infarction, stroke, heart failure, and arrhythmia. The WHO Environmental Noise Guidelines and recent reviews confirm a heightened risk of cardiovascular incidents with increasing transportation noise levels.

OBJECTIVE

We present a narrative review of the evidence from epidemiologic studies and translation studies on the adverse cardiovascular effects of transportation noise.

METHODS

We describe the results of a recent Umbrella+ review that combines the evidence used in the 2018 WHO Environmental Noise Guidelines with more recent (post-2015) high-quality systematic reviews of original studies. High-quality systematic reviews were included based on the quality of literature search, risk of bias assessment, and meta-analysis methodology using AMSTAR 2.

RESULTS

Epidemiologic studies show that exposure to high levels of road traffic noise for several years lead to numerous adverse health outcomes, including premature deaths, ischemic heart disease (IHD), chronic sleep disturbances, and increased annoyance. Mechanistically, noise exposure triggers oxidative stress, inflammation, endothelial dysfunction, and circadian rhythm disruptions. These processes involve the activation of NADPH oxidase, mitochondrial dysfunction, and nitric oxide synthase uncoupling, leading to vascular and cardiac damage. Studies indicate that chronic noise exposure does not result in habituation, and susceptible individuals, such as those with pre-existing CVD, are particularly vulnerable.

Upregulation of ALOX12-12-HETE pathway impairs AMPK-dependent modulation of vascular metabolism in ApoE/LDLR-/- mice

Mitochondrial dysfunction and 12-lipoxygenase (ALOX12)-derived 12(S)-HETE production have been associated with vascular inflammation and the pathogenesis of atherosclerosis. However, the role of ALOX12 in regulating vascular energy metabolism in vascular inflammation has not been studied to date. Using mitochondrial and glycolysis functional profiling with the Seahorse extracellular flux analyzer, metabolipidomics, and proteomic analysis (LC-MS/MS), we characterized alterations in vascular energy metabolism in 2- and 6-month-old ApoE/LDLR-/- vs. control C57BL/6 mice. We identified that aorta of 6-month-old ApoE/LDLR-/- mice displayed compromised mitochondrial metabolism manifested by the reduced expression of mitochondrial enzymes, impaired mitochondrial respiration, and consequently diminished respiratory reserve capacity. An increased flux through the glycolysis/lactate shuttle, the hexosamine biosynthetic pathway (HBP), and the pentose phosphate pathway (PPP) was also recognized. Interestingly, ALOX12-12-HETE was the most upregulated axis in eicosanoid metabolism and histological examinations indicated that ApoE/LDLR-/- mice showed increased aortic expression of ALOX12, particularly in early atherosclerotic plaque areas. Remarkably, the joint blocking of ALOX12 and activation of AMPK, but not AMPK activation alone, resulted in the reprogramming of vascular metabolism, with improved mitochondrial respiration and suppressed auxiliary pathways (HBP, PPP, itaconate shunt). In conclusion, excessive activation of the ALOX12-12-HETE pathway in vascular inflammation in early atherosclerosis inhibits AMPK-dependent regulation of vascular metabolism. Consequently, ALOX12 may represent a novel target to boost impaired vascular mitochondrial function in pro-atherosclerotic vascular inflammation.

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.

Immune and inflammatory mechanisms in hypertension

Hypertension is a global health problem, with >1.3 billion individuals with high blood pressure worldwide. In this Review, we present an inflammatory paradigm for hypertension, emphasizing the crucial roles of immune cells, cytokines and chemokines in disease initiation and progression. T cells, monocytes, macrophages, dendritic cells, B cells and natural killer cells are all implicated in hypertension. Neoantigens, the NLRP3 inflammasome and increased sympathetic outflow, as well as cytokines (including IL-6, IL-7, IL-15, IL-18 and IL-21) and a high-salt environment, can contribute to immune activation in hypertension. The activated immune cells migrate to target organs such as arteries (especially the perivascular fat and adventitia), kidneys, the heart and the brain, where they release effector cytokines that elevate blood pressure and cause vascular remodelling, renal damage, cardiac hypertrophy, cognitive impairment and dementia. IL-17 secreted by CD4+ T helper 17 cells and γδ T cells, and interferon-γ and tumour necrosis factor secreted by immunosenescent CD8+ T cells, exert crucial effector roles in hypertension, whereas IL-10 and regulatory T cells are protective. Effector mediators impair nitric oxide bioavailability, leading to endothelial dysfunction and increased vascular contractility. Inflammatory effector mediators also alter renal sodium and water balance and promote renal fibrosis. These mechanisms link hypertension with obesity, autoimmunity, periodontitis and COVID-19. A comprehensive understanding of the immune and inflammatory mechanisms of hypertension is crucial for safely and effectively translating the findings to clinical practice.

Transportation Noise Pollution and Cardiovascular Health

Epidemiological studies have found that transportation noise increases the risk for cardiovascular morbidity and mortality, with solid evidence for ischemic heart disease, heart failure, and stroke. According to the World Health Organization, at least 1.6 million healthy life years are lost annually from traffic-related noise in Western Europe. Traffic noise at night causes fragmentation and shortening of sleep, elevation of stress hormone levels, and increased oxidative stress in the vasculature and the brain. These factors can promote vascular (endothelial) dysfunction, inflammation, and arterial hypertension, thus elevating cardiovascular risk. The present review focusses on the indirect, nonauditory cardiovascular health effects of noise. We provide an updated overview of epidemiological research on the effects of transportation noise on cardiovascular risk factors and disease, and mechanistic insights based on the latest clinical and experimental studies and propose new risk markers to address noise-induced cardiovascular effects in the general population. We will discuss the potential effects of noise on vascular dysfunction, oxidative stress, and inflammation in humans and animals. We will elaborately explain the underlying pathomechanisms by alterations of gene networks, epigenetic pathways, circadian rhythm, signal transduction along the neuronal-cardiovascular axis, and metabolism. We will describe current and future noise mitigation strategies. Finally, we will conduct an overall evaluation of the status of the current evidence of noise as a significant cardiovascular risk factor.

[Air pollution, noise and hypertension : Partners in crime]

Air pollution and traffic noise are two important environmental risk factors that endanger health in urban societies and often act together as "partners in crime". Although air pollution and noise often co-occur in urban environments, they have typically been studied separately, with numerous studies documenting consistent effects of individual exposure on blood pressure. In the following review article, we examine the epidemiology of air pollution and noise, especially regarding the cardiovascular risk factor arterial hypertension and the underlying pathophysiology. Both environmental stressors have been shown to lead to endothelial dysfunction, oxidative stress, pronounced vascular inflammation, disruption of circadian rhythms and activation of the autonomic nervous system, all of which promote the development of hypertension and cardiovascular diseases. From a societal and political perspective, there is an urgent need to point out the potential dangers of air pollution and traffic noise in the American Heart Association (AHA)/American College of Cardiology (ACC) prevention guidelines and the European Society of Cardiology (ESC) guidelines on prevention. Therefore, an essential goal for the future is to raise awareness of environmental risk factors as important and, in particular, preventable risk factors for cardiovascular diseases.

Health position paper and redox perspectives - Disease burden by transportation noise

Transportation noise is a ubiquitous urban exposure. In 2018, the World Health Organization concluded that chronic exposure to road traffic noise is a risk factor for ischemic heart disease. In contrast, they concluded that the quality of evidence for a link to other diseases was very low to moderate. Since then, several studies on the impact of noise on various diseases have been published. Also, studies investigating the mechanistic pathways underlying noise-induced health effects are emerging. We review the current evidence regarding effects of noise on health and the related disease-mechanisms. Several high-quality cohort studies consistently found road traffic noise to be associated with a higher risk of ischemic heart disease, heart failure, diabetes, and all-cause mortality. Furthermore, recent studies have indicated that road traffic and railway noise may increase the risk of diseases not commonly investigated in an environmental noise context, including breast cancer, dementia, and tinnitus. The harmful effects of noise are related to activation of a physiological stress response and nighttime sleep disturbance. Oxidative stress and inflammation downstream of stress hormone signaling and dysregulated circadian rhythms are identified as major disease-relevant pathomechanistic drivers. We discuss the role of reactive oxygen species and present results from antioxidant interventions. Lastly, we provide an overview of oxidative stress markers and adverse redox processes reported for noise-exposed animals and humans. This position paper summarizes all available epidemiological, clinical, and preclinical evidence of transportation noise as an important environmental risk factor for public health and discusses its implications on the population level.

Systemic health effects of noise exposure

Noise, any unwanted sound, is pervasive and impacts large populations worldwide. Investigators suggested that noise exposure not only induces auditory damage but also produces various organ system dysfunctions. Although previous reviews primarily focused on noise-induced cardiovascular and cerebral dysfunctions, this narrow focus has unintentionally led the research community to disregard the importance of other vital organs. Indeed, limited studies revealed that noise exposure impacts other organs including the liver, kidneys, pancreas, lung, and gastrointestinal tract. Therefore, the aim of this review was to examine the effects of noise on both the extensively studied organs, the brain and heart, but also determine noise impact on other vital organs. The goal was to illustrate a comprehensive understanding of the systemic effects of noise. These systemic effects may guide future clinical research and epidemiological endpoints, emphasizing the importance of considering noise exposure history in diagnosing various systemic diseases.

Aircraft noise exposure and risk for recurrent cardiovascular events after acute coronary syndrome: A prospective patient cohort study

In several population based cohort studies associations between aircraft noise and various diagnoses of cardiovascular disease were observed. However, no study has yet addressed the risk of recurrences in relation to transportation noise in patients with acute coronary heart disease. We conducted a prospective patient cohort study of 737 individuals recruited from eleven cardiac centers in the Rhine-Main region in the vicinity of Frankfurt Airport. All patients had an angiographically confirmed acute coronary syndrome diagnosed between July 2013 and November 2018. Individual aircraft noise exposure at the place of residence was calculated using Soundplan software, and exposure to road traffic and railway noise was obtained from noise maps provided by the Hessian State Agency. Data was analyzed by means of Cox regression adjusted for relevant confounders. Recurrent event as non-fatal endpoint was defined as myocardial infarction, stroke, bypass surgery or percutaneous coronary intervention with stent implantation. In addition, all-cause mortality was evaluated. Follow-up data including socioeconomic and confounder information was obtained from 663 (90%) patients covering a mean follow-up period of 42 (range: 1-80) months. Mean Lden aircraft noise exposure was 48.1 dB. Adjusted hazard ratio (HR) for recurrence was 1.24 (95%-CI: 0.97-1.58) per 10 dB increase in Lden aircraft noise exposure. A combined analysis of recurrence and all-cause mortality yielded a HR of 1.31 (95%-CI: 1.03-1.66). Similar HRs were found for Lday and Lnight aircraft noise exposure. HRs for road traffic and railway noise were above unity but less pronounced and not significant. Observed exposure-response associations for aircraft noise were more pronounced than previously observed in population-based cohort studies suggesting that acute coronary heart disease patients are particularly vulnerable to effects from transportation noise. Measures to reduce environmental noise exposure may thus be helpful in improving clinical outcome of patients with coronary heart disease.

Too Loud to Handle? Transportation Noise and Cardiovascular Disease

The World Health Organization reported that more than 1.6 million healthy life-years are lost yearly from traffic-related noise in western Europe. In addition, the number of studies on health side effects in response to traffic noise is steadily growing, mainly cardiovascular disease, such as acute and chronic ischemic heart disease, heart failure, arrhythmia, and stroke. Pathophysiologically nighttime noise has been shown to cause sleep disturbances, including too short sleep periods and frequent interruption of sleep leading to an increase in the levels of circulating stress hormones and subsequently to a significant increase in the production of reactive oxygen species (oxidative stress) and inflammation in the vasculature and the brain. The consequence is arterial hypertension and vascular (endothelial) dysfunction, which might increase the risk of cardiovascular disease. With the present review, we give an overview of the "so-called" nonauditory cardiovascular health effects of noise, which have been proposed to be responsible for the future development of cardiovascular disease. We present epidemiological evidence but also evidence provided by translational human and experimental noise studies. Finally, we discuss manoeuvres to mitigate noise effectively.