Long-term community noise exposure in relation to dementia, cognition, and cognitive decline in older adults

Unraveling the Threads: Sleep Difficulties, Neighborhood Physical Disorder, and Subjective Cognitive Decline in Older Americans

Background

Research suggests that the neighborhood in which people live can be a risk or protective factor for various health outcomes, including cognitive decline to Alzheimer's disease. Similar to the impact of neighborhood on health outcomes, sleep difficulties have been linked to cognitive function in older adults. However, few studies have examined how neighborhood physical disorders moderate the effects of sleep on subjective cognitive decline (SCD).

Objective

The study examined the moderating effect of neighborhood factors on the relationship between sleep difficulties and SCD.

Methods

Data were obtained from 2,494 respondents (1,065 males and 1,429 females) from Wave 11 of the National Health and Aging Trends (NHATS) data. Sleep difficulties were operationalized as the presence of difficulties in falling and staying asleep. Neighborhood physical disorder (e.g., vandalism, graffiti) was based on interviewer observations of respondents' neighborhoods. SCD was operationalized as subjective reports of increasing or worse memory loss in the past 12 months and present memory rating. We utilized Linear regression to test neighborhood physical disorder as a moderator of the relationship between sleep difficulties and SCD.

Results

We found a significant interaction between sleep difficulties and neighborhood physical disorder on SCD (β=0.03, SE = 0.01, 95% CI[0.00,0.51], p < 0.001). Participants who reported higher average sleep difficulties and higher levels of neighborhood physical disorder were more likely to report SCD.

Conclusions

Our findings add to inform future health interventions and policy recommendations that address modifiable sources of cognitive decline and risk of Alzheimer's disease.

Overlooked cases of mild cognitive impairment: Implications to early Alzheimer's disease

Mild cognitive impairment (MCI) marks the initial phase of memory decline or other cognitive functions like language or spatial perception, while individuals typically retain the capacity to carry out everyday tasks independently. Our comprehensive article investigates the intricate landscape of cognitive disorders, focusing on MCI and Alzheimer's disease (AD) and Alzheimer's disease-related dementias (ADRD). The study aims to understand the signs of MCI, early Alzheimer's disease, and healthy brain aging while assessing factors influencing disease progression, pathology development and susceptibility. A systematic literature review of over 100 articles was conducted, emphasizing MCI, AD and ADRD within the elderly populations. The synthesis of results reveals significant findings regarding ethnicity, gender, lifestyle, comorbidities, and diagnostic tools. Ethnicity was found to influence MCI prevalence, with disparities observed across diverse populations. Gender differences were evident in cognitive performance and decline, highlighting the need for personalized management strategies. Lifestyle factors and comorbidities were identified as crucial influencers of cognitive health. Regarding diagnostic tools, the Montreal Cognitive Assessment (MoCA) emerged as superior to the Mini-Mental State Examination (MMSE) in early MCI detection. Overall, our article provides insights into the multifaceted nature of cognitive disorders, emphasizing the importance of tailored interventions and comprehensive assessment strategies for effective cognitive health management.

Road traffic noise exposure and its impact on health: evidence from animal and human studies-chronic stress, inflammation, and oxidative stress as key components of the complex downstream pathway underlying noise-induced non-auditory health effects

In heavily urbanized world saturated with environmental pollutants, road traffic noise stands out as a significant factor contributing to widespread public health issues. It contributes in the development of a diverse range of non-communicable diseases, such as cardiovascular diseases, metabolic dysregulation, cognitive impairment, and neurodegenerative disorders. Although the exact mechanisms behind these non-auditory health effects remain unclear, the noise reaction model centres on the stress response to noise. When exposed to noise, the body activates the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, leading to the secretion of stress hormones like catecholamines and cortisol. Prolonged exposure to noise-induced stress results in chronic inflammation and oxidative stress. This review underscores the role of inflammation and oxidative stress in the progression of noise-induced vascular dysfunction, disruption of the circadian rhythm, accelerated aging, neuroinflammation, and changes in microbiome. Additionally, our focus is on understanding the interconnected nature of these health outcomes: These interconnected factors create a cascade effect, contributing to the accumulation of multiple risk factors that ultimately lead to severe adverse health effects.

Neural Mechanisms of Nonauditory Effects of Noise Exposure on Special Populations

Due to the abnormal structure and function of brain neural networks in special populations, such as children, elderly individuals, and individuals with mental disorders, noise exposure is more likely to have negative psychological and cognitive nonauditory effects on these individuals. There are unique and complex neural mechanisms underlying this phenomenon. For individuals with mental disorders, there are anomalies such as structural atrophy and decreased functional activation in brain regions involved in emotion and cognitive processing, such as the prefrontal cortex (PFC). Noise exposure can worsen these abnormalities in relevant brain regions, further damaging neural plasticity and disrupting normal connections and the transmission of information between the PFC and other brain areas by causing neurotransmitter imbalances. In the case of children, in a noisy environment, brain regions such as the left inferior frontal gyrus and PFC, which are involved in growth and development, are more susceptible to structural and functional changes, leading to neurodegenerative alterations. Furthermore, noise exposure can interrupt auditory processing neural pathways or impair inhibitory functions, thus hindering children's ability to map sound to meaning in neural processes. For elderly people, age-related shrinkage of brain regions such as the PFC, as well as deficiencies in hormone, neurotransmitter, and nutrient levels, weakens their ability to cope with noise. Currently, it is feasible to propose and apply coping strategies to improve the nonauditory effects of noise exposure on special populations based on the plasticity of the human brain.

Systematic Review of Longitudinal Evidence and Methodologies for Research on Neighborhood Characteristics and Brain Health

Objective: Synthesize longitudinal research evaluating neighborhood environments and cognition to identify methodological approaches, findings, and gaps. Methods: Included studies evaluated associations between neighborhood and cognition longitudinally among adults >45 years (or mean age of 65 years) living in developed nations. We extracted data on sample characteristics, exposures, outcomes, methods, overall findings, and assessment of disparities. Results: Forty studies met our inclusion criteria. Most (65%) measured exposure only once and a majority focused on green space and/or blue space (water), neighborhood socioeconomic status, and recreation/physical activity facilities. Similarly, over half studied incident impairment, cognitive function or decline (70%), with one examining MRI (2.5%) or Alzheimer's disease (7.5%). While most studies used repeated measures analysis to evaluate changes in the brain health outcome (51%), many studies did not account for any type of correlation within neighborhoods (35%). Less than half evaluated effect modification by race/ethnicity, socioeconomic status, and/or sex/gender. Evidence was mixed and dependent on exposure or outcome assessed. Conclusion: Although longitudinal research evaluating neighborhood and cognitive decline has expanded, gaps remain in types of exposures, outcomes, analytic approaches, and sample diversity.

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.

Relationship Between Work-Related Noise Exposure and Cognitive Impairment: A Cross-Sectional Study in China

Background

Noise exposure and the risk of cognitive impairment are currently major public health issues.

Objective

This study aimed to analyze the relationship between noise exposure and early impairment of cognitive function from the perspective of occupational epidemiology and to provide evidence for the long-term prevention and treatment of dementia in the context of aging.

Methods

This study was conducted in China between May and August 2021. The independent variables were the type of hazardous factors, duration of noise exposure, perceived noise intensity, and cumulative noise exposure (CNE). The dependent variable was cognitive function, which was measured using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Multiple linear and logistic regression were used to analyze the relationship between noise exposure and cognitive function and to establish an effect curve.

Results

The detection rates of cognitive dysfunction using the MMSE and MoCA were 1.1% and 36.2%, respectively. The predicted MMSE and MoCA scores showed a downward trend within the CNE value ranging from 90-140 dB.time. Each unit increase in CNE decreased cognitive function scores by 0.025 (0.037, 0.013) and 0.020 (0.037, 0.003) points,respectively.

Conclusions

From the perspective of occupational epidemiology, these findings reveal a potential link between long-term noise exposure and early cognitive impairment.

Thirty Risk Factors for Alzheimer's Disease Unified by a Common Neuroimmune-Neuroinflammation Mechanism

One of the major obstacles confronting the formulation of a mechanistic understanding for Alzheimer's disease (AD) is its immense complexity-a complexity that traverses the full structural and phenomenological spectrum, including molecular, macromolecular, cellular, neurological and behavioural processes. This complexity is reflected by the equally complex diversity of risk factors associated with AD. However, more than merely mirroring disease complexity, risk factors also provide fundamental insights into the aetiology and pathogenesis of AD as a neurodegenerative disorder since they are central to disease initiation and subsequent propagation. Based on a systematic literature assessment, this review identified 30 risk factors for AD and then extended the analysis to further identify neuroinflammation as a unifying mechanism present in all 30 risk factors. Although other mechanisms (e.g., vasculopathy, proteopathy) were present in multiple risk factors, dysfunction of the neuroimmune-neuroinflammation axis was uniquely central to all 30 identified risk factors. Though the nature of the neuroinflammatory involvement varied, the activation of microglia and the release of pro-inflammatory cytokines were a common pathway shared by all risk factors. This observation provides further evidence for the importance of immunopathic mechanisms in the aetiopathogenesis of AD.

Association between Noise and Cardiovascular Disease in a Nationwide U.S. Prospective Cohort Study of Women Followed from 1988 to 2018

BACKGROUND

Long-term noise exposure is associated with cardiovascular disease (CVD), including acute cardiovascular events such as myocardial infarction and stroke. However, longitudinal cohort studies in the U.S. of long-term noise and CVD are almost exclusively from Europe and few modeled nighttime noise, when an individual is likely at home or asleep, separately from daytime noise. We aimed to examine the prospective association of outdoor long-term nighttime and daytime noise from anthropogenic sources with incident CVD using a U.S.-based, nationwide cohort of women.

METHODS

We linked L 50 nighttime and L 50 daytime anthropogenic modeled noise estimates from a U.S. National Parks Service model (L 50 : sound pressure levels exceeded 50 percent of the time) to geocoded residential addresses of 114,116 participants in the Nurses' Health Study. We used time-varying Cox proportional hazards models to estimate risk of incident CVD, coronary heart disease (CHD), and stroke associated with long-term average (14-y measurement period) noise exposure, adjusted for potential individual- and area-level confounders and CVD risk factors (1988-2018; biennial residential address updates; monthly CVD updates). We assessed effect modification by population density, region, air pollution, vegetation cover, and neighborhood socioeconomic status, and explored mediation by self-reported average nightly sleep duration.

RESULTS

Over 2,548,927 person-years, there were 10,331 incident CVD events. In fully adjusted models, the hazard ratios for each interquartile range increase in L 50 nighttime noise (3.67 dBA) and L 50 daytime noise (4.35 dBA), respectively, were 1.04 (95% CI: 1.02, 1.06) and 1.04 (95% CI: 1.02, 1.07). Associations for total energy-equivalent noise level (L eq ) measures were stronger than for the anthropogenic statistical L 50 noise measures. Similar associations were observed for CHD and stroke. Interaction analyses suggested that associations of L 50 nighttime and L 50 daytime noise with CVD did not differ by prespecified effect modifiers. We found no evidence that inadequate sleep (< 5 h/night) mediated associations of L 50 nighttime noise and CVD.

DISCUSSION

Outdoor L 50 anthropogenic nighttime and daytime noise at the residential address was associated with a small increase in CVD risk in a cohort of adult female nurses. https://doi.org/10.1289/EHP12906.

Neighborhood Built Environments and Health in Later Life: A Literature Review

Objectives: This literature review aims to assess the current state of the field linking neighborhood environments to later-life health and wellbeing. Methods: We used electronic databases (e.g., PubMed, Google Scholar, and ProQuest) to search for studies published between 2010 and 2022 examining associations between neighborhood built environmental variables and later-life physical, cognitive, mental, and social health outcomes. Results: Among 168 studies reviewed, the majority were quantitative (n = 144) and cross-sectional (n = 122). Neighborhood environmental variables significantly associated with later-life health outcomes included population density/rurality, walkability/street connectivity, access to services and amenities, neighborhood quality and disorder, and parks/green/blue/open space. Neighborhoods operated through behavioral and biological pathways including hazardous exposures, affective states (e.g., stress and restoration), and lifestyle (e.g., exercise, socialization, and diet). Discussion: Neighborhoods and healthy aging research is a burgeoning interdisciplinary and international area of scholarship. Findings can inform upstream community interventions and strengthen clinical care.

Exposure to sounds during sleep impairs hippocampal sharp wave ripples and memory consolidation

Sleep is critical for the consolidation of recent experiences into long-term memories. As a key underlying neuronal mechanism, hippocampal sharp-wave ripples (SWRs) occurring during sleep define periods of hippocampal reactivation of recent experiences and have been causally linked with memory consolidation. Hippocampal SWR-dependent memory consolidation during sleep is often referred to as occurring during an "offline" state, dedicated to processing internally generated neural activity patterns rather than external stimuli. However, the brain is not fully disconnected from the environment during sleep. In particular, sounds heard during sleep are processed by a highly active auditory system which projects to brain regions in the medial temporal lobe, reflecting an anatomical pathway for sound modulation of hippocampal activity. While neural processing of salient sounds during sleep, such as those of a predator or an offspring, is evolutionarily adaptive, whether ongoing processing of environmental sounds during sleep interferes with SWR-dependent memory consolidation remains unknown. To address this question, we used a closed-loop system to deliver non-waking sound stimuli during or following SWRs in sleeping rats. We found that exposure to sounds during sleep suppressed the ripple power and reduced the rate of SWRs. Furthermore, sounds delivered during SWRs (On-SWR) suppressed ripple power significantly more than sounds delivered 2 seconds after SWRs (Off-SWR). Next, we tested the influence of sound presentation during sleep on memory consolidation. To this end, SWR-triggered sounds were applied during sleep sessions following learning of a conditioned place preference paradigm, in which rats learned a place-reward association. We found that On-SWR sound pairing during post-learning sleep induced a complete abolishment of memory retention 24 h following learning, while leaving memory retention immediately following sleep intact. In contrast, Off-SWR pairing weakened memory 24 h following learning as well as immediately following learning. Notably, On-SWR pairing induced a significantly larger impairment in memory 24 h after learning as compared to Off-SWR pairing. Together, these findings suggest that sounds heard during sleep suppress SWRs and memory consolidation, and that the magnitude of these effects are dependent on sound-SWR timing. These results suggest that exposure to environmental sounds during sleep may pose a risk for memory consolidation processes.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents

Noise affects people of all ages. Noise-induced hearing loss, a major problem for adults, is also a problem for young people. Sensorineural hearing loss is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, sleep, and quality of life. Children and adolescents have unique vulnerabilities. Infants and young children must rely on adults to remove them from noisy situations; children may not recognize hazardous noise exposures; teenagers often do not understand consequences of high exposure to music from personal listening devices or attending concerts and dances. Personal listening devices are increasingly used, even by small children. Environmental noise has disproportionate effects on underserved communities. This statement and its accompanying technical report review common sources and effects of noise as well as specific pediatric exposures. Because noise exposure often starts in infancy and effects are cumulative, more attention to noise in everyday activities is needed starting early in life. Pediatricians can potentially lessen harms by raising awareness of children's specific vulnerabilities to noise. Safer listening is possible. Noise exposure is underrecognized as a serious public health issue in the United States. Greater awareness of noise hazards is needed at a societal level.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents

Noise exposure is a major cause of hearing loss in adults. Yet, noise affects people of all ages, and noise-induced hearing loss is also a problem for young people. Sensorineural hearing loss caused by noise and other toxic exposures is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, and quality of life. Children and adolescents have unique vulnerabilities to noise. Children may be exposed beginning in NICUs and well-baby nurseries, at home, at school, in their neighborhoods, and in recreational settings. Personal listening devices are increasingly used, even by small children. Infants and young children cannot remove themselves from noisy situations and must rely on adults to do so, children may not recognize hazardous noise exposures, and teenagers generally do not understand the consequences of high exposure to music from personal listening devices or attending concerts and dances. Environmental noise exposure has disproportionate effects on underserved communities. In this report and the accompanying policy statement, common sources of noise and effects on hearing at different life stages are reviewed. Noise-abatement interventions in various settings are discussed. Because noise exposure often starts in infancy and its effects result mainly from cumulative exposure to loud noise over long periods of time, more attention is needed to its presence in everyday activities starting early in life. Listening to music and attending dances, concerts, and celebratory and other events are sources of joy, pleasure, and relaxation for many people. These situations, however, often result in potentially harmful noise exposures. Pediatricians can potentially lessen exposures, including promotion of safer listening, by raising awareness in parents, children, and teenagers. Noise exposure is underrecognized as a serious public health issue in the United States, with exposure limits enforceable only in workplaces and not for the general public, including children and adolescents. Greater awareness of noise hazards is needed at a societal level.

Relationships of Residential Distance to Major Traffic Roads with Dementia Incidence and Brain Structure Measures: Mediation Role of Air Pollution

Background: Uncertainty exists regarding the operating pathways between near-roadway exposure and dementia incidence. We intend to examine relationships between proximity to major roadways with dementia incidence and brain MRI structure measures, and potential mediation roles of air and noise pollution. Methods: The cohort study was based on the UK Biobank. Baseline survey was conducted from 2006 to 2010, with linkage to electronic health records conducted for follow-up. Residential distance to major roadways was ascertained residential address postcode. A land use regression model was applied for estimating traffic-related air pollution at residence. Dementia incidence was ascertained using national administrative databases. Brain MRI measures were derived as image-derived phenotypes, including total brain, white matter, gray matter, and peripheral cortical gray matter. Results: We included 460,901 participants [mean (SD) age: 57.1 (8.1) years; men: 45.7%]. Compared with individuals living >1,000 m from major traffic roads, living ≤1,000 m was associated with a 13% to 14% higher dementia risk, accounting for 10% of dementia cases. Observed association between residential distance and dementia was substantially mediated by traffic-related air pollution, mainly nitrogen dioxide (proportion mediated: 63.6%; 95% CI, 27.0 to 89.2%) and PM2.5 (60.9%, 26.8 to 87.0%). The shorter residential distance was associated with smaller volumes of brain structures, which was also mediated by traffic-related air pollutants. No significant mediation role was observed of noise pollution. Conclusions: The shorter residential distance to major roads was associated with elevated dementia incidence and smaller brain structure volumes, which was mainly mediated by traffic-related air pollution.

Association of long-term air pollution and ambient noise with cognitive decline in the heinz nixdorf recall study

Little is known about the impact of long-term ambient air pollution (AP) and noise exposure on change in cognitive function over years in the elderly. In this study, we wanted to examine the association between long-term exposure to AP and noise with the rate of cognitive decline in a population aged 50 and older and susceptible groups with mild cognitive impairment or at a genetically higher risk of Alzheimer's disease (Apolipoprotein E ε4 positive). Participants in the German population-based Heinz Nixdorf Recall study carried out five neuropsychological tests. Individual tests scores at the first (T₁ = 2006-2008) and second (T₂ = 2011-2015) follow-up for each test were used as outcomes after standardization using predicted means adjusted for age and education. Global cognitive score (GCS) was defined as sum of five standardized scores of individual tests. Long-term exposures to particulate matter (PM_2.5, PM₁₀, PM_2.5 absorbance), accumulation mode particle number (PN_acc), a proxy of ultrafine particles, and nitrogen dioxide were estimated by the land-use regression and chemistry transport models. Noise exposures were assessed as outdoor weighted nighttime road traffic noise (L_night) means. We performed linear regression analyses adjusted for sex, age, individual and neighborhood socio-economic status, and lifestyle variables. Effect modification in vulnerable groups was estimated using multiplicative interaction terms between exposure and a modifier. Overall, 2554 participants (49.5% men, median age is 63 (IQR = 12)) were included. We found weak associations between higher exposure to PM₁₀ and PM_2.5 with faster decline in the immediate verbal memory test. Adjustment for potential confounders and for co-exposures did not change the results. We saw no effects on GCS, and no effect of noise exposure. In susceptible groups, higher AP and noise exposure were tended to be associated with faster decline in GCS. Our results suggest that AP exposure may accelerate cognitive decline in older ages, particularly in susceptible groups.

Why might urban tree canopy reduce dementia risk? A causal mediation analysis of 109,688 adults with 11 years of hospital and mortality records

Urban tree canopy is associated with lower dementia risk, but no mediation analysis has been attempted to reveal potential mechanisms. We examined 3,639 dementia diagnoses in 109,688 participants of the Sax Institute's 45 and Up Study. Adjusted models indicated ≥20% tree canopy lowered the odds of developing dementia by 14% over 11 years (Odds Ratio = 0.86, 95%CI = 0.79-0.93). Association between tree canopy and dementia was partially mediated by physical activity (4.5%) and absences of psychological distress (5.7%), social support (2.9%), sleep duration (2.3%) and diabetes (1.8%). Social loneliness and absence of heart disease or hypertension did not mediate the tree canopy-dementia association.

Association Between Neighborhood Socioeconomic Status and 30-Day Mortality and Readmission for Patients With Common Neurologic Conditions

BACKGROUND AND OBJECTIVES

Patients of low individual socioeconomic status (SES) are at a greater risk of unfavorable health outcomes. However, the association between neighborhood socioeconomic deprivation and health outcomes for patients with neurologic disorders has not been studied at the population level. Our objective was to determine the association between neighborhood socioeconomic deprivation and 30-day mortality and readmission after hospitalization for various neurologic conditions.

METHODS

This was a retrospective study of nationwide Medicare claims from 2017 to 2019. We included patients older than 65 years hospitalized for the following broad categories based on diagnosis-related groups (DRGs): multiple sclerosis and cerebellar ataxia (DRG 058-060); stroke (061-072); degenerative nervous system disorders (056-057); epilepsy (100-101); traumatic coma (082-087), and nontraumatic coma (080-081). The exposure of interest was neighborhood SES, measured by the area deprivation index (ADI), which uses socioeconomic indicators, such as educational attainment, unemployment, infrastructure access, and income, to estimate area-level socioeconomic deprivation at the level of census block groups. Patients were grouped into high, middle, and low neighborhood-level SES based on ADI percentiles. Adjustment covariates included age, comorbidity burden, race/ethnicity, individual SES, and sex.

RESULTS

After exclusions, 905,784 patients were included in the mortality analysis and 915,993 were included in the readmission analysis. After adjustment for age, sex, race/ethnicity, comorbidity burden, and individual SES, patients from low SES neighborhoods had higher 30-day mortality rates compared with patients from high SES neighborhoods for all disease categories except for multiple sclerosis: magnitudes of the effect ranged from an adjusted odds ratio of 2.46 (95% CI 1.60-3.78) for the nontraumatic coma group to 1.23 (95% CI 1.19-1.28) for the stroke group. After adjustment, no significant differences in readmission rates were observed for any of the groups.

DISCUSSION

Neighborhood SES is strongly associated with 30-day mortality for many common neurologic conditions even after accounting for baseline comorbidity burden and individual SES. Strategies to improve health equity should explicitly consider the effect of neighborhood environments on health outcomes.

Noise-induced auditory damage affects hippocampus causing memory deficits in a model of early age-related hearing loss

Several studies identified noise-induced hearing loss (NIHL) as a risk factor for sensory aging and cognitive decline processes, including neurodegenerative diseases, such as dementia and age-related hearing loss (ARHL). Although the association between noise- and age-induced hearing impairment has been widely documented by epidemiological and experimental studies, the molecular mechanisms underlying this association are not fully understood as it is not known how these risk factors (aging and noise) can interact, affecting memory processes. We recently found that early noise exposure in an established animal model of ARHL (C57BL/6 mice) accelerates the onset of age-related cochlear dysfunctions. Here, we extended our previous data by investigating what happens in central brain structures (auditory cortex and hippocampus), to assess the relationship between hearing and memory impairment and the possible combined effect of noise and sensory aging on the cognitive domain. To this aim, we exposed juvenile C57BL/6 mice of 2 months of age to repeated noise sessions (60 min/day, pure tone of 100 dB SPL, 10 kHz, 10 consecutive days) and we monitored auditory threshold by measuring auditory brainstem responses (ABR), spatial working memory, by using the Y-maze test, and basal synaptic transmission by using ex vivo electrophysiological recordings, at different time points (1, 4 and 7 months after the onset of noise exposure, corresponding to 3, 6 and 9 months of age). We found that hearing loss, along with accelerated presbycusis onset, can induce persistent synaptic alterations in the auditory cortex. This was associated with decreased memory performance and oxidative-inflammatory injury in the hippocampus, the extra-auditory structure involved in memory processes. Collectively, our data confirm the critical relationship between auditory and memory circuits, suggesting that the combined detrimental effect of noise and sensory aging on hearing function can be considered a high-risk factor for both sensory and cognitive degenerative processes, given that early noise exposure accelerates presbycusis phenotype and induces hippocampal-dependent memory dysfunctions.

All-Natural Moss-Based Microstructural Composites in Deformable Form for Use as Graffiti and Artificial-Porous-Material Replacement

Although artificial porous materials are useful for dissipating acoustic waves, they pose a major environmental threat as most are non-recyclable. Developing sustainable structural materials with the mechanical and energy-absorption properties required to replace artificial porous materials is currently a key challenge. Here, we report, for the first time, a novel microstructure using all-natural moss with a compressive strength of up to 2.35 GPa and a sound-absorption performance of up to 90%, depending on the additives, such as yogurt, starch, and beer. In addition, the moss-based microstructure was applied as graffiti to a three-dimensionally printed house model to demonstrate improved performance against the effects of sound. By incorporating energy-absorbing materials without harmful substances, the desired structure can be decorated with the graffiti method. This work could pave the way for attenuating sound-wave and impact noise by using graffiti work on structural composite materials.

Environmental Factors in the Rehabilitation Framework: Role of the One Health Approach to Improve the Complex Management of Disability

Environment factors play a crucial implication in human health, with strong evidence suggesting that several biological, chemical, physical and social factors could be possible targets to implement effective strategies for human health promotion. On the other hand, a large gap of knowledge still exists about the implications of environmental factors in terms of functional impairment and disability, while the integration of an environmental-based approach in the therapeutic care of patients affected by disabilities remains still challenging. In this scenario, the One Health approach has been recently introduced in clinical care and aims to optimize health outcomes by recognizing the interconnection between people and the environment. Concurrently, the "Rehabilitation 2030 Initiative" proposed in 2017 by the WHO emphasized the need to integrate environmental-based strategies to promote rehabilitation across different health systems and different nations. However, no previous study underlined the potential implications of the One Health approach in the rehabilitation setting, nor the role of a comprehensive rehabilitation approach focused on environmental factors. Therefore, the aim of this narrative review was to present a comprehensive overview of the data currently available assessing the close relationship between rehabilitation and the environment to provide a different perspective on the comprehensive care of patients affected by disability.

Environmental noise-induced cardiovascular, metabolic and mental health disorders: a brief review

BACKGROUND

Environmental noise is a pervasive pollutant that is one of the greatest environmental threats to mental, physiological and psychological well-being and has a significant global health burden associated with it. Many epidemiological studies indicate long-term relationship of noise pollution with wide range of metabolic, cardio-vascular and respiratory disorders and diseases.

OBJECTIVE

The goal of this study was to thoroughly analyse available literature on public health implications and various underlying biological mechanisms associated with ambient noise exposure, taking into account both objective and subjective measures of noise exposure.

METHODS

A search of literature for review on environmental noise and associated cardiovascular, mental health and metabolic implications on human health was done using Web of Science, Google Scholar and PubMed databases.

DISCUSSION

Experimental studies indicate that noise exposure leads to endocrine effects, increased incidence of diabetes, impairment of cognitive performance, sleep disturbance and annoyance. Epidemiological evidence indicates that high levels of noise, particularly at night, may cause arterial hypertension and endothelial dysfunction due to higher level of stress hormones and oxidative stress. An increased incidence of cardio-vascular diseases like myocardial infarction, heart rate, ischemic heart disease, stroke and heart failure is associated with noise-induced mental stress. Furthermore, psychological and mental health issues like anxiety and depression are also related with exposure to noise pollution.

CONCLUSION

This article summarises a comprehensive and systematic knowledge established in recent noise research with the spotlight on cardiovascular, metabolic and mental health disorders of environmental noise, providing unique understanding into underlying mechanisms.

Cerebral consequences of environmental noise exposure

The importance of noise exposure as a major environmental determinant of public health is being increasingly recognized. While in recent years a large body evidence has emerged linking environmental noise exposure mainly to cardiovascular disease, much less is known concerning the adverse health effects of noise on the brain and associated neuropsychiatric outcomes. Despite being a relatively new area of investigation, indeed, mounting research and conclusive evidence demonstrate that exposure to noise, primarily from traffic sources, may affect the central nervous system and brain, thereby contributing to an increased risk of neuropsychiatric disorders such as stroke, dementia and cognitive decline, neurodevelopmental disorders, depression, and anxiety disorder. On a mechanistic level, a significant number of studies suggest the involvement of reactive oxygen species/oxidative stress and inflammatory pathways, among others, to fundamentally drive the adverse brain health effects of noise exposure. This in-depth review on the cerebral consequences of environmental noise exposure aims to contribute to the associated research needs by evaluating current findings from human and animal studies. From a public health perspective, these findings may also help to reinforce efforts promoting adequate mitigation strategies and preventive measures to lower the societal consequences of unhealthy environments.

Chronic Noise Exposure and Risk of Dementia: A Systematic Review and Dose-Response Meta-Analysis

Objective

Evidence is scarce about the effect of noise exposure on the risk of dementia. We conducted a systematic review and dose-response meta-analysis, aiming to explore the association between noise exposure and the risk of dementia.

Methods

We searched PubMed, EMBASE and the Cochrane Library to collect studies on chronic noise exposure and the risk of dementia from database inception to September 18, 2021 without language limitations. Two authors independently screened the literature, extracted data and assessed the risk of bias of the included studies. A dose-response meta-analysis and subgroup analysis were then conducted to detect the association between noise exposure and the risk of dementia by using Stata 14.0 software. This study is registered on PROSPERO (CRD42021249243).

Results

A total of 11 studies were eligible for qualitative synthesis, and nine were eligible for quantitative data synthesis. All of them showed moderate to high quality scores in the assessment of risk of bias. We found a positive linear association between the noise increment and dementia risk (R2 = 0.58). When noise exposure increased 57 dB, the RR of dementia was 1.47 (95% CI: 1.21–1.78). From the outcome subgroup of AD, AD and dementia, VaD and NAD, we also found a positive association (R2 = 0.68, 0.68, 0.58, respectively). When noise exposure increased by 25 dB, the RRs were 1.18 (95% CI: 1.14–1.23), 1.19 (95% CI: 1.14–1.23) and 1.17 (95% CI: 1.06–1.30), respectively. We found a nonlinear association between the noise increment and dementia risk when only cohort studies were included (R2 = 0.58). When noise exposure increased by 25 dB, the RR of dementia was 1.16 (95% CI: 1.12–1.20). From the subgroup of AD, AD and dementia, VaD and NAD of cohort studies, the regression curve showed a nonlinear positive association (R2 = 0.74, 0.71, 0.43, respectively). When noise exposure increased by 25 dB, the RRs were 1.17 (95% CI: 1.12–1.21), 1.17 (95% CI: 1.12–1.22) and 1.13 (95% CI: 0.99–1.28), respectively.

Conclusion

Based on the current evidence, exposure to noise may be a specific risk factor for dementia. To better prevent dementia, more rigorously designed studies are needed to explore the etiological mechanism of noise and dementia.

Noise as a cause of neurodegenerative disorders: molecular and cellular mechanisms

Noise as an environmental stressor becomes of increasing importance in our industrialized world, and especially traffic noise from the environment represents a potential novel neurodegenerative risk factor, as well as for hearing loss. A significant number of studies have been suggested that the overproduction of reactive oxygen species (ROS) has a complex role in stimulation of pathologic events. Experimental studies upon molecular pathways of traffic noise exposure proposed that it increased the level of stress hormones and mediated the inflammatory and oxidative stress (OS) pathways resulting in endothelial and neuronal dysfunction. Studies have shown that neurons are especially sensitive to OS due to high polyunsaturated fatty acids content in membranes, high oxygen uptake, and weak antioxidant defense. However, OS induces the necrotic and apoptotic cell deaths in the cochlea. Chronic noise is one of the many overall reasons of obtained sensorineural hearing loss which destroys cognitive functions in human and animals, as well as suppresses neurogenesis in the hippocampus. Nevertheless, behavioral disorders caused by noise are mainly accompanied with oxidative stress, but the clear molecular mechanism of neurodegeneration due to disruption of the pro- and antioxidant systems is still not fully understood. This paper aims to highlight the down-stream pathophysiology of noise-induced mental disorders, including hearing loss, annoyance, anxiety, depression, memory loss, and Alzheimer's disease, describing the underlying mechanisms of induction of inflammation and oxidative stress.

Residential Green Space and Cognitive Function in a Large Cohort of Middle-Aged Women

Importance

Green space can decelerate cognitive decline by supporting physical activity, psychological restoration, or reducing exposure to air pollution. However, existing studies on the association of green space with cognitive decline are limited.

Objective

To examine whether residential green space was associated with cognitive function in middle-aged women.

Design, Setting, and Participants

Starting in 1989, the Nurses' Health Study II enrolled 116 429 female nurses aged 25 to 42 years residing in the US. In 2014 to 2016, 40 082 women were invited to complete an online cognitive battery. This cohort study analyzed women who had data on both green space exposure and cognitive measures. Data analysis was conducted from June to October 2021.

Exposures

Residential exposure to green space was assessed using the Normalized Difference Vegetation Index, a satellite-derived indicator of the quantity of ground vegetation. Landsat satellite data at 270-m and 1230-m buffers around each participants' residential addresses in 2013 were used.

Main Outcomes and Measures

In 2014 to 2016, cognitive function was measured using a self-administered online battery, the Cogstate Brief Battery, consisting of 4 tasks measuring psychomotor speed, attention, learning, and working memory; 3 composite scores, averaging together all tasks, psychomotor speed/attention, and learning/working memory, were created. In addition, the study evaluated potential mediators, including air pollution, depression, and physical activity.

Results

The analytical sample included 13 594 women, of whom 13 293 (98%) were White. Mean (SD) age was 61.2 (4.6) years. In models adjusted for age at assessment, race, childhood, adulthood, and neighborhood socioeconomic status, green space was associated with higher scores on the global Cogstate composite (mean difference per IQR in green space, 0.05; 95% CI, 0.02 to 0.07), and psychomotor speed/attention (mean difference in score, 0.05 standard units; 95% CI, 0.02 to 0.08). This difference in scores is similar to the difference observed in women 1 year apart in age in the data. By contrast, there was no association between green space and learning/working memory (mean difference, 0.0300; 95% CI, -0.0003 to 0.0500).

Conclusions and Relevance

These findings suggest that increasing residential green space may be associated with modest benefits in cognition in middle-aged women.

Effects of Lifestyle Factors on Cognition in Minority Population of Older Adults: A Review

The onset of dementia and Alzheimer's disease (AD) is projected to expand over the next several decades in the United States as the population ages. However, the cognitive health burden is not equally distributed among the population, as Hispanics and African Americans are at higher risk of AD when compared with Non-Hispanic Whites. There is some evidence to indicate that cognitive decline may be associated with lifestyle factors and that interventions in these domains may prevent or delay this decline. These lifestyle factors include social engagement, physical activity, both aerobic and strength training, dietary intake, sleep and stress. This review summarizes, in general, what is known about the relationship between risk factors and cognition and, in particular what is known about this relationship in minority populations. The results show that the relationship between these risk factors and cognitive decline is stronger for some of the factors such as physical activity and dietary intake and weaker for the other factors depending on what is measured and in what populations. It does appear, however, that the studies in minority populations is limited and warrants more targeted research and interventions.

Noise pollution and human cognition: An updated systematic review and meta-analysis of recent evidence

BACKGROUND

This systematic review provides a comprehensive synthesis of recent epidemiological evidence that environmental noise negatively impacts human cognition.

METHODS

We update a prior review with recent publications (PROSPERO CRD42019151923). The strength of evidence for associations was assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) framework. We also conducted random-effects meta-analyses where suitable.

RESULTS

16 studies were identified and reviewed in tandem with 32 studies previously reviewed by Clark & Paunovic (2018). A meta-analysis from 3 studies found that reading comprehension scores in quiet classrooms were 0.80 (95% confidence interval: 0.40; 1.20) points higher than children in noisier classrooms. Meta-analysis of the impact of 1 dB (dB) increase in environmental noise on reading and language abilities gave a pooled beta coefficient of -0.11(95% confidence interval: -0.32; 0.10). A meta-analysis of Odds Ratios (OR) from 3 studies found higher odds of cognitive impairment in people aged 45 + with higher residential noise exposure (OR 1.40, 95% CI: 1.18;1.61). After qualitative synthesis of remaining studies, there was high quality evidence for an association between environmental noise and cognitive impairment in middle-to-older adults, moderate quality evidence for an association between aircraft noise and reading and language in children, and moderate quality evidence against an association between aircraft noise and executive functioning in children. Generally the literature was supportive for other cognitive outcomes, but with low or very low-quality evidence.

DISCUSSION

The evidence so far suggests that noise exposure is associated with cognition, but more good quality research using standardised methodology is required to corroborate these results and to allow for precise risk estimation by larger meta-analyses. There is also a need for more research with older teenagers and young-to-middle aged adults, on the synergistic effects of noise and air pollution, and in Africa, Central and South America, South Asia and Australasia.

Long-Term Exposures to Urban Noise and Blood Pressure Levels and Control Among Older Adults

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Relationship Between Chronic Noise Exposure, Cognitive Impairment, and Degenerative Dementia: Update on the Experimental and Epidemiological Evidence and Prospects for Further Research

Degenerative dementia, of which Alzheimer's disease is the most common form, is characterized by the gradual deterioration of cognitive function. The events that trigger and promote degenerative dementia are not clear, and treatment options are limited. Experimental and epidemiological studies have revealed chronic noise exposure (CNE) as a potential risk factor for cognitive impairment and degenerative dementia. Experimental studies have indicated that long-term exposure to noise might accelerate cognitive dysfunction, amyloid-β deposition, and tau hyperphosphorylation in different brain regions such as the hippocampus and cortex. Epidemiological studies are increasingly examining the possible association between external noise exposure and dementia. In this review, we sought to construct a comprehensive summary of the relationship between CNE, cognitive dysfunction, and degenerative dementia. We also present the limitations of existing evidence as a guide regarding important prospects for future research.

Perceived environmental pollution and subjective cognitive decline (SCD) or SCD-related functional difficulties among the general population

This study aimed to determine whether perceived environmental pollution is associated with subjective cognitive decline (SCD) or SCD-related functional difficulties. We conducted a cross-sectional study using data from a nationwide sample of 191,054 individuals aged ≥19 years from the 2018 Korea Community Health Survey. Perceived air, water, soil, noise, and green space pollution was assessed. To investigate the dose-response effect of the amount of perceived environmental pollution, we determined whether an increasing number of types of perceived environmental pollution also increased the odds of having SCD or SCD-related functional difficulties. Among the 191,054 individuals, the prevalence of SCD and SCD-related functional difficulties was 17.7% (N = 33,853) and 2.2% (N = 4139), respectively. Perception of air, soil, or noise pollution was significantly associated with SCD. However, the perception of any type of environmental pollution was not significantly associated with SCD-related functional difficulties. With regard to a dose-response effect, individuals perceiving a greater number of types of environmental pollution had significantly higher odds of SCD or SCD-related functional difficulties. This association was notably more evident in the younger age group.