Comprehensive review of the current literature on impact of ambient air pollution and sleep quality

Environmental perceptions, self-regulation, and coping with noise mediate the associations between children's physical environment and sleep and mental health problems

BACKGROUND

Children face various challenges in their home and extended neighborhood settings. In this study, we examine the impact of the built and social environments on sleep/mental health and the potential mediating role of environmental perceptions, self-regulation, and coping with noise.

METHODS

Cross-sectional data for 1251 schoolchildren (8-12 years) were sampled in the Tyrol region of Austria/Italy. Questionnaires provided information on sociodemographic and housing factors, perceived neighborhood quality, coping with noise during homework, self-regulation, sleep, and mental health problems. A built environment score was based on modeled levels of road and rail traffic noise, nitrogen dioxide, and imperviousness density. Home garden represented availability of accessible greenspace. Associations between predictors and mental health/sleep problems were examined using quantile regressions and structural equation modeling (SEM).

RESULTS

In multivariate regressions, poor neighborhood quality, poor self-regulation, low traffic safety, and higher coping efforts were associated with more mental health and sleep problems. Good family relations acted in the opposite direction. In SEM, the built environment score was associated with lower neighborhood quality and lower traffic safety, which in turn led to higher coping efforts, and then to mental health/sleep problems. Home gardens related to less sleep problems through higher perceived neighborhood quality and lower coping efforts. Good family relations were associated with better mental health/sleep directly and via better self-regulation and lower coping efforts.

CONCLUSIONS

Children forced to engage in coping activities when disturbed by noise during homework show poorer mental health. Good family relations, good neighborhood quality, and close-by greenspace may be factors to alleviate built environment stressors. The negative association of required coping with noise during homework suggests that children, in contrast to adults, may be limited in their coping abilities. Our findings call for further inquiries, as children and their environments may vary with respect to coping efficiency.

Long-term exposure to ozone and sleep disorders in children: A multicity study in China

Evidence regarding the link between long-term ambient ozone (O3) exposure and childhood sleep disorders is little. This study aims to examine the associations between long-term exposure to O3 and sleep disorders in children. We conducted a population-based cross-sectional survey, including 185,428 children aged 6-18 years in 173 schools across 14 Chinese cities during 2012 and 2018. Parents or guardians completed a checklist using Sleep Disturbance Scale for Children, and O3 exposure at residential and school addresses was estimated using a satellite-based spatiotemporal model. We used generalized linear mixed models to test the associations with adjustment for factors including socio-demographic variables, lifestyle, meteorology and multiple pollutants. Mean concentrations of O3, particulate matter with diameters ≤2.5 mm (PM2.5) and nitrogen dioxide (NO2) were 89.0 μg/m3, 42.5 μg/m3 and 34.4 μg/m3, respectively. O3 and NO2 concentrations were similar among provinces, while PM2.5 concentration varied significantly among provinces. Overall, 19.4% of children had at least one sleep disorder. Long-term exposure to O3 was positively associated with odds of sleep disorders for all subtypes. For example, each interquartile increment in home-school O3 concentrations was associated with a higher odds ratio for global sleep disorder, at 1.22 (95% confidence interval: 1.18, 1.26). Similar associations were observed for sleep disorder subtypes. The associations remained similar after adjustment for PM2.5 and NO2. Moreover, these associations were heterogeneous regionally, with more prominent associations among children residing in southeast region than in northeast and northwest regions in China. We concluded that long-term exposure to O3 is positively associated with risks of childhood sleep disorders. These associations varied by geographical region of China.

Association of long-term exposure to PM2.5 and its chemical components with the reduced quality of sleep

Poor sleep quality is a widespread concern. While the influence of particle exposure on sleep disturbances has received considerable attention, research exploring other dimensions of sleep quality and the chemical components of the particles remains limited. We employed a marginal structural model to explore the association of long-term exposure to PM2.5 and its chemical components with poor sleep quality. The odds ratio (95 % CI) for poor sleep quality was 1.335 (1.292-1.378), 1.097 (1.080-1.113), 1.137 (1.100-1.174), 1.197 (1.156-1.240), and 1.124 (1.107-1.140) per IQR increase in the concentration of PM2.5, SO42-, NO3-, NH4+, and BC, respectively. The score (and 95 % CI) of sleep latency, use of sleep medication, habitual sleep efficiency, subjective sleep quality, and daytime dysfunction were affected by PM2.5, with an increase of 0.059 (0.050-0.069), 0.054 (0.049-0.059), 0.011 (0.008-0.014), 0.011 (0.005-0.018), and 0.026 (0.018-0.034) per IQR increase in PM2.5 concentrations, respectively. This study supports the association of long-term exposure to PM2.5 and its chemical components with poor sleep quality.

Temperature exposure and sleep duration: Evidence from time use surveys

The Earth's climate is projected to warm significantly in the 21st century, and this will affect human societies in many ways. Since sleep is a basic human need and part of everyone's life, the question of how temperature affects human sleep naturally arises. This paper examines the effect of daily mean temperature on sleep duration using nationally representative Hungarian time use surveys between 1976 and 2010. Compared to a day with an average temperature of 5-10 °C, colder temperatures do not influence sleep duration. However, as daily mean temperatures rise, sleep duration starts to strongly decline. The effect of a hot (>25 °C) day is -13.3 minutes, but if preceded by a few other hot days, the effect is even stronger, -24.7 minutes. The estimated sleep loss is especially large on weekends and public holidays, for older individuals, and men. Combining the estimated effects with temperature projections of twenty-four climate models shows that the warming climate will substantially decrease sleep duration. The projected impacts are especially large when taking into account the effects of heatwave days. This study also shows that different groups in society are likely to be affected in significantly different ways by a warming climate.

Ambient particulate matter and surrounding greenness in relation to sleep quality among pregnant women: A nationwide cohort study

Background

Particulate air pollution and residential greenness are associated with sleep quality in the general population; however, their influence on maternal sleep quality during pregnancy has not been assessed.

Objective

This cross-sectional study investigated the individual and interactive effects of exposure to particulate matter (PM) air pollution and residential greenness on sleep quality in pregnant women.

Methods

Pregnant women (n = 4933) enrolled in the Korean Children's Environmental Health Study with sleep quality information and residential address were included. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). The average concentrations of PM (PM2.5 and PM10) during pregnancy were estimated through land use regression, and residential greenness in a 1000 m buffer area around participants' residences was estimated using the Normalized Difference Vegetation Index (NDVI1000-m). Modified Poisson regression models were used to estimate the associations between PM and NDVI and poor sleep quality (PSQI >5) after controlling for a range of covariates. A four-way mediation analysis was conducted to examine the mediating effects of PM.

Results

After adjusting for confounders, each 10 μg/m3 increase in PM2.5 and PM10 exposure was associated with a higher risk of poor sleep quality (relative risk [RR]: 1.06; 95% confidence interval [CI]: 1.01, 1.11; and RR: 1.09; 95% CI: 1.06, 1.13, respectively), and each 0.1-unit increase in NDVI1000-m was associated with a lower risk of poor sleep quality (RR: 0.97; 95% CI: 0.95, 0.99). Mediation analysis showed that PM mediated approximately 37%-56% of the association between residential greenness and poor sleep quality.

Conclusions

This study identified a positive association between residential greenness and sleep quality. Furthermore, these associations are mediated by a reduction in exposure to particulate air pollution and highlight the link between green areas, air pollution control, and human health.

Physical activity attenuates the association of long-term exposure to nitrogen dioxide with sleep quality and its dimensions in Chinese rural older adults

BACKGROUND

Joint impacts of air pollution and physical activity (PA) on sleep quality remain unaddressed. We aimed to investigate whether PA attenuates the association of long-term exposure to nitrogen dioxide (NO2) with sleep quality and its dimensions in older adults.

METHODS

This study included 3408 Chinese rural older adults. Annual NO2 was estimated using the Space-Time Extra-Trees model. PA was assessed by International Physical Activity Questionnaire. Sleep quality was evaluated using Pittsburgh Sleep Quality Index (PSQI) scale. Linear regression models were used to assess the associations of long-term NO2 exposure and PA with sleep quality and its dimensions, and interaction plots were used to depict the attenuating effect of PA on associations of NO2 with sleep quality and its dimensions.

RESULTS

Three-year (3-y) average NO2 (per 0.64-μg/m3 increment) was positively associated with global PSQI (β = 0.41, 95 % CI: 0.23, 0.59), sleep duration (β = 0.16, 95 % CI: 0.11, 0.21), and habitual sleep efficiency (β = 0.22, 95 % CI: 0.17, 0.27), while PA was negatively associated with global PSQI (β = -0.33, 95 % CI: -0.46, -0.20) and five domains of PSQI other than sleep duration and sleep disturbances. The associations of NO2 with global PSQI, sleep duration, and habitual sleep efficiency were attenuated with increased PA (Pinteraction were 0.037, 0.020, and 0.079, respectively).

CONCLUSIONS

PA attenuates the adverse impacts of long-term NO2 exposure on sleep quality, especially on sleep duration, and habitual sleep efficiency, in Chinese rural elderly people. Participating in PA should be encouraged in this population, and continued efforts are still needed to reduce air pollution.

Social and built neighborhood environments and sleep health: The Hispanic Community Health Study/Study of Latinos Community and Surrounding Areas and Sueño Ancillary Studies

STUDY OBJECTIVES

To test associations between neighborhood social, built, and ambient environment characteristics and multidimensional sleep health in Hispanic/Latino adults.

METHODS

Data were from San Diego-based Hispanic/Latino adults mostly of Mexican heritage enrolled in the Hispanic Community Health Study/Study of Latinos (N = 342). Home addresses were geocoded to ascertain neighborhood characteristics of greenness, walkability (density of intersections, retail spaces, and residences), socioeconomic deprivation (e.g. lower income, lower education), social disorder (e.g. vacant buildings, crime), traffic density, and air pollution (PM 2.5) in the Study of Latinos Communities and Surrounding Areas Study. Sleep dimensions of regularity, satisfaction, alertness, timing, efficiency, and duration were measured by self-report or actigraphy approximately 2 years later. Multivariable regression models accounting for study design (stratification and clustering) were used to examine associations of neighborhood variables with individual sleep dimensions and a multidimensional sleep health composite score.

RESULTS

Neighborhood characteristics were not significantly associated with the multidimensional sleep health composite, and there were few significant associations with individual sleep dimensions. Greater levels of air pollution (B = 9.03, 95% CI: 1.16, 16.91) were associated with later sleep midpoint, while greater social disorder (B = -6.90, 95% CI: -13.12, -0.67) was associated with earlier sleep midpoint. Lower walkability was associated with more wake after sleep onset (B = -3.58, 95% CI: -7.07, -0.09).

CONCLUSIONS

Living in neighborhoods with lower walkability and greater air pollution was associated with worse sleep health, but otherwise findings were largely null. Future research should test these hypotheses in settings with greater variability and investigate mechanisms of these associations.

Chlordane exposure impairs the growth and behavior of Drosophila

Chlordane, a previously extensively utilized insecticidal pesticide, has since been prohibited, however, owing to its limited degradability, it continues to persist significantly in soil and water reservoirs, subsequently accumulating within plant and animal organisms, representing a substantial threat to human health. Despite extensive research conducted over the past few decades to investigate the toxic effects of chlordane, there remains a notable dearth of studies focusing on its impact on sleep activity. Therefore, in this study, the effects of short-term and long-term exposure to chlordane on the activity and sleep of Drosophila were investigated. When exposed to chlordane at a concentration of 1 μM, Drosophila lost body weight, decreased body size and resulted in lipid metabolism disorders. In addition, chlordane exposure altered the arousal and sleep behaviors of Drosophila. Short-term exposure to chlordane resulted in an increase in night-time sleep duration, while long-term exposure to chlordane resulted in an increase in activity and a decrease in sleep, as evidenced by a decrease in the duration of each sleep session and the appearance of sleep fragmentation. Under conditions of long-term chlordane exposure, reactive oxygen species levels were significantly up-regulated in Drosophila. Our results suggest that long-term chlordane exposure triggers oxidative stress damage in Drosophila, leading to sleep disruption. This study offers novel insights into the harmful impacts of environmental pollutants on human sleep patterns and proposes that mitigating the presence of chlordane in the environment could potentially contribute to the reduction of global sleep disorder prevalence.

Association between air pollution and sudden sensorineural hearing loss (SSHL): A systematic review and meta-analysis

Recent studies have indicated that air pollution (AP) has harmful effects on hearing and ear diseases such as Sudden Sensorineural Hearing Loss (SSHL). The purpose of this study was to evaluate the impact of exposure to AP on SSHL incidence. Valid electronic databases were searched to retrieve studies published until December 1, 2022, using appropriate keywords. The result of the search was 1146 studies, and after screening according to the defined criteria, in total 8 studies were obtained. The risk of bias (ROB) in the studies and their quality were assessed. Finally, the meta-analysis with a significance level of 5% was performed. The findings revealed that the mean level of SO2, CO, NO2, and PM10 in the patient group was more than that of the control group, and p-values were 0.879, 0.144, 0.077, and 0.138, respectively. There was an indirect relation between air pollutants and SSHL, and PM2.5 showed a significant effect (p < 0.05). Given the limited research and the use of different statistical methods, more research is suggested to confirm this association and to determine the mechanisms by which AP exposure may cause SSHL.

Family income as a moderator of relations between sleep and physical health during adolescence

OBJECTIVES

Sleep duration, quality, and consistency are associated with overall physical health in adolescence, yet the effects of sleep on development may be not uniform because both sleep and physical health vary systematically along gradients of family income. To understand "for whom" sleep may be particularly beneficial, the present study tested family income as a moderator of relations between youth sleep and physical health.

METHODS

Three hundred twenty-three youth (M age=17.39years; 53% female; 41% Black, 59% White) wore wrist actigraphs for 1week at home. Four well-recognized sleep parameters were derived: minutes, efficiency, long wake episodes, and variability in minutes across the week. Parents reported family income, and mothers rated adolescents' physical health. In independent path models, physical health was regressed onto each indicator of sleep, family income, and Sleep × Family Income interactions to test potential moderation effects.

RESULTS

Associations between sleep and physical health were moderated by family income. Lower sleep efficiency, more long wake episodes, and more variability in sleep minutes were associated with poorer physical health among adolescents from lower-income families. At optimal levels of all sleep variables, income-based differences in physical health were mitigated. Youth from higher-income families tended to have better physical health regardless of their sleep.

CONCLUSIONS

Findings build evidence that sleep has relations with physical health for low-income youth in particular. Clinicians and other service providers working with youth might benefit from considering the role of sleep in prevention and interventions programs geared toward improving health.

Association between air pollutant exposure, body water distribution and sleep disorder indices in individuals with low-arousal-threshold obstructive sleep apnoea

BACKGROUND

Air pollution may alter body water distribution, it may also be linked to low-arousal-threshold obstructive sleep apnoea (low-ArTH OSA). Here, we explored the mediation effects of air pollution on body water distribution and low-ArTH OSA manifestations.

METHODS

In this retrospective study, we obtained sleep centre data from healthy participants and patients with low-ArTH OSA (N=1924) in northern Taiwan. Air pollutant exposure at different time intervals (1, 3, 6 and 12 months) was estimated using the nearest station estimation method, and government air-quality data were also obtained. Regression models were used to assess the associations of estimated exposure, sleep disorder indices and body water distribution with the risk of low-ArTH OSA. Mediation analysis was performed to explore the relationships between air pollution, body water distribution and sleep disorder indices.

RESULTS

First, exposure to particulate matter (PM) with a diameter of ≤10 µm (PM10) for 1 and 3 months and exposure to PM with a diameter of ≤2.5 µm (PM2.5) for 3 months were significantly associated with the Apnoea-Hypopnoea Index (AHI), Oxygen Desaturation Index (ODI), Arousal Index (ArI) and intracellular-to-extracellular water ratio (I-E water ratio). Significant associations were observed between the risk of low-ArTH OSA and 1- month exposure to PM10 (OR 1.42, 95% CI 1.09 to 1.84), PM2.5 (OR 1.33, 95% CI 1.02 to 1.74) and ozone (OR 1.27, 95% CI 1.01 to 1.6). I-E water ratio alternation caused by 1-month exposure to PM10 and 3-month exposure to PM2.5 and PM10 had partial mediation effects on AHI and ODI.

CONCLUSION

Air pollution can directly increase sleep disorder indices (AHI, ODI and ArI) and alter body water distribution, thus mediating the risk of low-ArTH OSA.

Air pollution, glymphatic impairment, and Alzheimer's disease

Epidemiological evidence demonstrates a link between air pollution exposure and the onset and progression of cognitive impairment and Alzheimer's disease (AD). However, current understanding of the underlying pathophysiological mechanisms is limited. This opinion article examines the hypothesis that air pollution-induced impairment of glymphatic clearance represents a crucial etiological event in the development of AD. Exposure to airborne particulate matter (PM) leads to systemic inflammation and neuroinflammation, increased metal load, respiratory and cardiovascular dysfunction, and sleep abnormalities. All these factors are known to reduce the efficiency of glymphatic clearance. Rescuing glymphatic function by restricting the impact of causative agents, and improving sleep and cardiovascular system health, may increase the efficiency of waste metabolite clearance and subsequently slow the progression of AD. In sum, we introduce air pollution-mediated glymphatic impairment as an important mechanistic factor to be considered when interpreting the etiology and progression of AD as well as its responsiveness to therapeutic interventions.

Interactions between long-term ambient particle exposures and lifestyle on the prevalence of hypertension and diabetes: insight from a large community-based survey

INTRODUCTION

Evidence on the interaction of lifestyle and long-term ambient particle (PM) exposure on the prevalence of hypertension, diabetes, particularly their combined condition is limited. We investigate the associations between PM and these outcomes and whether the associations were modified by various lifestyles.

METHODS

This was a large population-based survey during 2019-2021 in Southern China. The concentrations of PM were interpolated and assigned to participants by the residential address. Hypertension and diabetes status were from questionnaires and confirmed with the community health centres. Logistic regression was applied to examine the associations, followed by a comprehensive set of stratified analyses by the lifestyles including diet, smoking, drinking, sleeping and exercise.

RESULTS

A total of 82 345 residents were included in the final analyses. For each 1 μg/m3 increase in PM2.5, the adjusted OR for the prevalence of hypertension, diabetes and their combined condition were 1.05 (95% CI 1.05 to 1.06), 1.07 (95% CI 1.06 to 1.08) and 1.05 (95% CI 1.04 to 1.06), respectively. We observed that the association between PM2.5 and the combined condition was greatest in the group with 4-8 unhealthy lifestyles (OR=1.09, 95% CI 1.06 to 1.13) followed by the group with 2-3 and those with 0-1 unhealthy lifestyle (P interaction=0.026). Similar results and trends were observed in PM10 and/or in those with hypertension or diabetes. Individuals who consumed alcohol, had inadequate sleep duration or had poor quality sleep were more vulnerable.

CONCLUSION

Long-term PM exposure was associated with increased prevalence of hypertension, diabetes and their combined condition, and those with unhealthy lifestyles suffered greater risks of these conditions.

Associations between air pollution, intracellular-to-extracellular water distribution, and obstructive sleep apnea manifestations

Background

Exposure to air pollution may be a risk factor for obstructive sleep apnea (OSA) because air pollution may alter body water distribution and aggravate OSA manifestations.

Objectives

This study aimed to investigate the mediating effects of air pollution on the exacerbation of OSA severity through body water distribution.

Methods

This retrospective study analyzed body composition and polysomnographic data collected from a sleep center in Northern Taiwan. Air pollution exposure was estimated using an adjusted nearest method, registered residential addresses, and data from the databases of government air quality motioning stations. Next, regression models were employed to determine the associations between estimated air pollution exposure levels (exposure for 1, 3, 6, and 12 months), OSA manifestations (sleep-disordered breathing indices and respiratory event duration), and body fluid parameters (total body water and body water distribution). The association between air pollution and OSA risk was determined.

Results

Significant associations between OSA manifestations and short-term (1 month) exposure to PM_2.5 and PM₁₀ were identified. Similarly, significant associations were identified among total body water and body water distribution (intracellular-to-extracellular body water distribution), short-term (1 month) exposure to PM_2.5 and PM₁₀, and medium-term (3 months) exposure to PM₁₀. Body water distribution might be a mediator that aggravates OSA manifestations, and short-term exposure to PM_2.5 and PM₁₀ may be a risk factor for OSA.

Conclusion

Because exposure to PM_2.5 and PM₁₀ may be a risk factor for OSA that exacerbates OSA manifestations and exposure to particulate pollutants may affect OSA manifestations or alter body water distribution to affect OSA manifestations, mitigating exposure to particulate pollutants may improve OSA manifestations and reduce the risk of OSA. Furthermore, this study elucidated the potential mechanisms underlying the relationship between air pollution, body fluid parameters, and OSA severity.

Indoor coal ash and school and social competency among children aged 6-14 years

BACKGROUND

A child's ability to succeed in social interactions and in a school setting are important for their development and growth. Exposure to environmental pollutants has been associated with poorer school performance and fewer social interaction in children. Fly ash, a waste product generated when burning coal for energy, is comprised of small glass spheres with neurotoxic heavy metal(loid)s found to be risk factors for learning and social problems in school.

OBJECTIVE

The purpose of this novel study was to assess the association of fly ash in children's homes with school and social competency.

METHODS

We recruited children aged 6-14 years old from communities located within 10 miles of two coal-burning power plants. In homes of the participants, fly ash was collected on polycarbonate filters using personal modular impactors. We measured school competency and social competency using the validated Child Behavioral Checklist. Using Tobit and linear regression we investigated the relationship of indoor fly ash with school and social competency.

RESULTS

Forty-three percent of children in the study had fly ash in their homes. In covariate-adjusted Tobit models, children with fly ash in their homes scored on average 2.63 (95% CI: -4.98, -0.28) points lower on the school competency scale than peers without ash in their homes. We did not observe that fly ash in homes was related with lower social competency.

SIGNIFICANCE

Results from this study suggest that children with fly ash in their homes had poorer performance in the school setting, compared to peers without fly ash in their homes. In the US, coal-fired power plants are being closed, however health concerns about pollution from coal ash storage facilities remains. Findings from this study can provide impetus for creating of public health policy and to highlight the need future research on children's exposure to fly ash.

IMPACT

Children's growth and development are impacted by their social interactions and ability to perform in school settings. Environmental pollutants may impact these essential elements of development. Millions of children are exposed to fly ash which is a waste product generated from burning coal. Fly ash, an environmental health threat throughout the world, is comprised of small glass spheres with trace concentrations of neurotoxic metal(loid)s. Findings from this research show that children with fly ash in their homes are significantly more likely to have poorer school performance than children without fly ash in their homes.

Is the development of digital finance conducive to reducing haze pollution? Empirical evidence from 284 cities in China

Using the panel data of 284 cities from 2011 to 2020 in China, this research statistically tests the direct impact and internal mechanism of digital finance on urban haze pollution. The results show the following: (1) the development of digital finance can significantly inhibit the concentration of urban haze, and there is a stronger inhibitory effect in areas where the government pays more emphasis to haze pollution and in cities with high levels; (2) after mechanism inspection, it is found that digital finance can indirectly promote urban haze pollution by influencing green innovation, cooperative innovation, industrial structure upgrading, and producer service agglomeration; (3) the results of the spatial econometric analysis show that digital finance can suppress the haze concentration in the region and simultaneously inhibit the neighboring areas through spillover effects; (4) further inspection shows that the spatial spillover effect of digital finance on haze pollution has an obvious spatial attenuation feature, demonstrating that a dense area of spatial spillover is within 310 km. The spillover effect gradually disappears when the threshold is exceeded.

Effects of air pollution and residential greenness on sleep disorder: A 8-year nationwide cohort study

BACKGROUND

Sleep disorder influencing the quality of life, however, its contributing factors have not been fully identified yet. Recently the potential effects of environmental exposures like air pollution and greenness on sleep disorder have attracted attention, but the evidence in China is limited, particularly in the middle-aged and elderly.

METHODS

We conducted a nationwide prospective study that included 21,878 Chinese citizens aged 45 years or above. For each participant, the 3-year averaged exposure concentrations of air pollutants (including PM₁₀, PM_2.5, PM₁, NO₂) and greenness (assessed by NDVI) were estimated based on residential address. We used mixed-effects logistic models to examine the associations of sustained air pollutants and greenness exposures with the occurrence of sleep disorder, and used linear mixed-effects models to assess the associations with sleep duration. Specifically, interaction effects models were employed to identify potential modificators of the above associations.

RESULTS

A total of 39,580 survey responses were received, with the overall occurrence rate of sleep disorder was 25.7%. A 10 μg/m³ increment in PM₁₀ and PM_2.5 were associated with increased occurrence of sleep disorder at 2% (aOR = 1.02, 95%CI:1.01, 1.04) and 7% (aOR = 1.07, 95%CI: 1.04, 1.11), and were associated with reduced sleep duration by 0.07 (95% CI: 0.08, 0.05) and 0.04 (95% CI: 0.05, 0.03) hours, respectively. Residential greenness appears to the potential protective factor for sleep disorder, that a 0.1 higher of the NDVI was associated a 9% (aOR = 0.91, 95%CI: 0.86, 0.96) decreased occurrence of sleep disorder and 0.09 h (95% CI: 0.05, 0.13) longer of sleep duration. Age and residence were identified as modificators of the above significant associations.

CONCLUSION

Sustained exposure to air pollutants can increase the occurrence of sleep disorder and can reduce sleep duration, while exposure to higher levels of greenness can protect sleep health from the side effects of air pollutants.

Associations Between Ambient Air Pollution and Cognitive Abilities from Midlife to Early Old Age: Modification by APOE Genotype

BACKGROUND

Fine particulate matter (PM2.5) and nitrogen dioxide (NO2) measures of ambient air pollution are associated with accelerated age-related cognitive impairment, and Alzheimer's disease and related dementias (ADRD).

OBJECTIVE

We examined associations between air pollution, four cognitive factors, and the moderating role of apolipoprotein E (APOE) genotype in the understudied period of midlife.

METHODS

Participants were ∼1,100 men in the Vietnam Era Twin Study of Aging. Baseline cognitive assessments were from 2003 to 2007. Measures included past (1993-1999) and recent (3 years prior to baseline assessment) PM2.5 and NO2 exposure, in-person assessment of episodic memory, executive function, verbal fluency, and processing speed, and APOE genotype. Average baseline age was 56 years with a 12-year follow-up. Analyses adjusted for health and lifestyle covariates.

RESULTS

Performance in all cognitive domains declined from age 56 to 68. Higher PM2.5 exposures were associated with worse general verbal fluency. We found significant exposure-by-APOE genotype interactions for specific cognitive domains: PM2.5 with executive function and NO2 with episodic memory. Higher PM2.5 exposure was related to worse executive function in APOE ɛ4 carriers, but not in non-carriers. There were no associations with processing speed.

CONCLUSION

These results indicate negative effects of ambient air pollution exposure on fluency alongside intriguing differential modifications of cognitive performance by APOE genotype. APOE ɛ4 carriers appeared more sensitive to environmental differences. The process by which air pollution and its interaction with genetic risk for ADRD affects risk for later life cognitive decline or progression to dementia may begin in midlife.

Can air purification improve sleep quality? A 2‐week randomised‐controlled crossover pilot study in healthy adults

Insufficient quantity and quality of sleep is a public health concern that can be addressed by interventions for improving sleep outcomes. Environmental factors such as poor air quality are a potential target for intervention, particularly in light of associations between air pollution and worse sleep. The aim of this pilot study was to investigate the effects of using an air purifier on sleep outcomes and mood in 30 healthy adults. There were two conditions: (i) air purifier with a high-efficiency particulate air filter; (ii) air purifier with a placebo filter. Participants undertook both conditions, each over 2 weeks with a 2-week washout, following a counterbalanced, double-blind design. Daily sleep outcomes were measured with actigraphy watches and sleep diaries, whilst daily mood was assessed with the Positive and Negative Affect Schedule. The Insomnia Severity Index, the Pittsburgh Sleep Quality Index, and symptoms of anxiety and depression were measured pre- and post-. The purifier filter was associated with increased total sleep time for an average of 12 min per night, and increased total time in bed for an average of 19 min per night relative to the placebo. There were several sleep and mood outcomes for which no changes were observed, and time awake after sleep onset was higher for the purifier filter. Air quality was better during the high-efficiency particulate air filter condition. These findings offer positive indications that environmental interventions that improve air quality can have benefits for sleep outcomes in healthy populations who are not exhibiting clinical sleep disturbances.

Determinants of natural adult sleep: An umbrella review

BACKGROUND

Sleep has a major impact on health, which makes it a relevant topic for research and health practitioners. Research on sleep determinants, i.e. factors that positively or negatively influence sleep, is fragmented.

OBJECTIVE

The purpose of this umbrella review is to provide an overview of the current evidence on determinants of natural adult sleep.

METHODS

A comprehensive literature search was performed on determinants of sleep. Reviews and meta-analyses on natural adult sleep were included. Six electronic databases (PubMed, WoS, Embase, CINAHL, PsycInfo and Cochrane) were used for the search, last accessed September 2021. The quality of the selected articles was assessed using the AMSTAR2 tool. Results were categorized in four main categories: biological, behavioral, environmental and personal/socio-economical determinants.

RESULTS

In total 93 reviews and meta-analyses resulted in a total of 30 identified determinants. The impact of each determinant differs per individual and per situation. Each determinant was found to affect different sleep parameters and the relationship with sleep is influenced by both generic and specific moderators.

DISCUSSION

A comprehensive overview on relevant sleep determinants provides a practical and scientifically based starting point to identify relevant intervention approaches to secure or improve individual sleep quality. The difference in aggregation level of the determinants and in measurement methods are the major limitations of this umbrella review. Extending existing generic sleep hygiene rules with an overview of all types of potential determinants will enhance the awareness of the complexity and can be used to improve the effect of sleep interventions in health promotion.

TRIAL REGISTRATION

The umbrella review was registered with PROSPERO (registration ID CRD42020149648) https://www.google.com/search?client=firefox-b-d&q=CRD42020149648.

Association between air pollution and 24-h movement behaviours in a representative sample of Spanish youth

PURPOSE

The aim of this study was to analyse the relationship between air pollution and 24-h movement guidelines in Spanish children/adolescents.

METHODS

This cross-sectional study analysed secondary data from the Encuesta Nacional de Salud Española (2017), a representative survey for the Spanish population. The original dataset included 6016 Spanish young people (aged 0-14 years). Since the data on 24-h movement recommendations were limited to Spanish young people aged 2-14 years, the final sample included 4398 (49.2% girls) Spanish young people. Air pollution was evaluated by particulate matter 2.5 (PM_2.5) from different Spanish regions and divided into tertiles representing areas with low, medium, and high pollution. Sleep duration and recreational screen time and were reported by the parents/caregivers. Physical activity was evaluated by an adapted version of the International Physical Activity Questionnaire. Time spent in screen time, sleep, and physical activity were classified as meeting or not the 24-h movement guidelines.

RESULTS

After adjusting for several covariates (sex, age, immigrant status, region, socioeconomic status, and body mass index), lower odds of meeting with the 24-h movement recommendations were found in those living in areas with medium (odds ratio [OR] = 0.55; confident interval [CI] 95%, 0.46-0.67) or high air pollution (OR = 0.45; CI 95%, 0.36-0.55), compared with those living in areas with low air pollution.

CONCLUSIONS

The movement behaviour of young people seems to be associated with the presence of air pollution among Spanish youth. Spanish public health agencies could consider the development of strategies to mitigate the health risks for children/adolescents in high air polluted areas.

Association of ambient air pollution exposure and its variability with subjective sleep quality in China: A multilevel modeling analysis

Growing epidemiological evidence has shown that exposure to ambient air pollution contributes to poor sleep quality. However, whether variability in air pollution exposure affects sleep quality remains unclear. Based on a large sample in China, this study linked individual air pollutant exposure levels and temporal variability with subjective sleep quality. Town-level data on daily air pollution concentration for 30 days prior to the survey date were collected, and the monthly mean value, standard deviations, number of heavily polluted days, and trajectory for six common pollutants were calculated to measure air pollution exposure and its variations. Sleep quality was subjectively assessed using the Pittsburgh Sleep Quality Index (PSQI), and a PSQI score above 5 indicated overall poor sleep quality. Multilevel and negative control models were used. Both air pollution exposure and variability contributed to poor sleep quality. A one-point increase in the one-month mean concentration of particulate matter with aerodynamic diameters of ≤2.5 μm (PM_2.5) and ≤10 μm (PM₁₀) led to 0.4% (95% confidence interval (CI): 1.002-1.006) and 0.3% (95% CI: 1.001-1.004) increases in the likelihoods of overall poor sleep quality (PSQI score >5), respectively; the odds ratios of a heavy pollution day with PM_2.5 and PM₁₀ were 2.2% (95% CI: 1.012-1.032) and 2.2% (95% CI: 1.012-1.032), respectively. Although the mean concentrations of nitrogen dioxide, sulfur dioxide, and carbon monoxide met the national standard, they contributed to the likelihood of overall poor sleep quality (PSQI score >5). A trajectory of air pollution exposure with maximum variability was associated with a higher likelihood of overall poor sleep quality (PSQI score >5). Subjective measures of sleep latency, duration, and efficiency (derived from PSQI) were affected in most cases. Thus, sleep health improvements should account for air pollution exposure and its variations in China under relatively high air pollution levels.

Planetary sleep medicine: Studying sleep at the individual, population, and planetary level

Circadian rhythms are a series of endogenous autonomous oscillators that are generated by the molecular circadian clock which coordinates and synchronizes internal time with the external environment in a 24-h daily cycle (that can also be shorter or longer than 24 h). Besides daily rhythms, there exist as well other biological rhythms that have different time scales, including seasonal and annual rhythms. Circadian and other biological rhythms deeply permeate human life, at any level, spanning from the molecular, subcellular, cellular, tissue, and organismal level to environmental exposures, and behavioral lifestyles. Humans are immersed in what has been called the "circadian landscape," with circadian rhythms being highly pervasive and ubiquitous, and affecting every ecosystem on the planet, from plants to insects, fishes, birds, mammals, and other animals. Anthropogenic behaviors have been producing a cascading and compounding series of effects, including detrimental impacts on human health. However, the effects of climate change on sleep have been relatively overlooked. In the present narrative review paper, we wanted to offer a way to re-read/re-think sleep medicine from a planetary health perspective. Climate change, through a complex series of either direct or indirect mechanisms, including (i) pollution- and poor air quality-induced oxygen saturation variability/hypoxia, (ii) changes in light conditions and increases in the nighttime, (iii) fluctuating temperatures, warmer values, and heat due to extreme weather, and (iv) psychological distress imposed by disasters (like floods, wildfires, droughts, hurricanes, and infectious outbreaks by emerging and reemerging pathogens) may contribute to inducing mismatches between internal time and external environment, and disrupting sleep, causing poor sleep quantity and quality and sleep disorders, such as insomnia, and sleep-related breathing issues, among others. Climate change will generate relevant costs and impact more vulnerable populations in underserved areas, thus widening already existing global geographic, age-, sex-, and gender-related inequalities.

Long-term exposure to ambient black carbon is associated with sleep disturbance in college students

BACKGROUND

Evidence suggests an association of air pollution with sleep quality. However, there is limited knowledge regarding the effect of black carbon, a key component of ambient particulate matter, on sleep.

OBJECTIVES

To investigate the association of long-term exposure to black carbon and sleep quality in a group of college students.

METHODS

A retrospective cohort study was conducted in five universities in different regions of China. The concentrations of black carbon and other environment factors were defined as the averages during the 6 years prior to the recruitment. Averagely daily dose of black carbon exposure was estimated according to the respiratory rate. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI) with a cutoff >5 indicating sleep disturbance. Linear regression and logistic regression models were used to estimate the association. The sensitivity analyses were conducted to estimate the effects of 1-month, 6-month and 1-year mean levels of exposure to black carbon on sleep quality.

RESULTS

A total of 20,053 incoming college students were included. 29.3% reported impaired sleep quality, with a mean PSQI score of 4.3 ± 2.2. The logistic regression showed that the risk of impaired sleep quality was positively associated with black carbon exposure, especially in the highest quantile (OR: 1.26, 95% CI: 1.11-1.43) compared with the lowest quartile after adjusting for potential confounders. Subgroup analysis showed that the effect of black carbon on sleep quality was stronger in participants with higher BMI, lower household income, and lower parental educational level. The results of sensitivity analyses were similar with main analyses.

CONCLUSION

Long-term exposure to black carbon is associated with sleep disturbance in college students. Improvement of air quality may help improve sleep quality.

Sleep disturbance exacerbates the cardiac conduction abnormalities induced by persistent heavy ambient fine particulate matter pollution: A multi-center cross-sectional study

Fine particulate matter (PM_2.5) exposure and sleep disturbance have been significantly associated with adverse cardiovascular outcomes, however, the combined effects of these two factors are still unclear. We conducted a multi-center cross-sectional study from November 2018 to May 2019 in the Beijing-Tianjin-Hebei region in China to investigate the potential modifying effects of sleep disturbance on associations between cardiac conduction abnormalities and PM_2.5 exposure, as well as the combined effects of sleep disturbance and heavy pollution episodes, which were defined based on the PM_2.5 mass concentration (≥75 μg/m³, falling in the 75th/90th percentile) and duration (1 day and ≥2 days). The sleep quality and sleep duration of all participants were evaluated using the Pittsburgh Sleep Quality Index. Standard 12-lead electrocardiogram (ECG) test was performed to measure the heart rate (HR), QRS duration (time taken for ventricular depolarization), HR corrected QT interval (time for ventricular depolarization and repolarization) and PR interval (time for atrioventricular conduction). Multivariable linear regression models were performed to evaluate the associations of PM_2.5 and heavy pollution events on ECG parameters and the joint effects with sleep disturbance. We found PM_2.5 exposure was independently associated with prolonged QRS and QTc intervals. Association between PM_2.5 and the QTc interval was significantly stronger in participants with poor sleep quality. For each 10-μg/m³ increase in PM_2.5 concentration, the QTc interval in the participants with poor sleep quality increased by 0.41 % (95 % confidence interval: 0.19, 0.64). In addition, heavy PM_2.5 pollution episodes, especially extremely heavy pollution of long duration, were found to have synergistic effects with sleep disturbance on ECG parameters. Our findings provide evidence that PM_2.5 exposure, especially heavy pollution episodes, may increase abnormal cardiac conduction and have a synergistic effect with sleep disturbance. Improving sleep hygiene is crucial to protect the heart health of the general population.

Association of air pollution exposure with low arousal threshold obstructive sleep apnea: A cross-sectional study in Taipei, Taiwan

Emerging evidence witnesses the association of air pollution exposure with sleep disorders or the risk of obstructive sleep apnea (OSA); however, the results are not consistent. OSA patients with or without a low arousal threshold (LAT) have different pathology and therapeutic schemes. No study has evaluated the potential diverse effects of air pollution on the phenotypes of OSA. The current study aimed to evaluate the associations of short-term and long-term exposure to air pollution with sleep-disordered measures and OSA phenotypes. This cross-sectional study consisted of 4634 participants from a sleep center in Taipei from January 2015 to April 2019. The personal exposure to ambient PM_2.5 and NO₂ was assessed by a spatial-temporal model. Overnight polysomnography was used to measure the sleep parameters. According to a developed clinical tool, we defined the low arousal threshold (LAT) and identified the OSA patients with or without LAT. We applied a generalized linear model and multinomial logistic regression model to estimate the change of sleep measures and risk of the OSA phenotypes, respectively, associated with an interquartile range (IQR) increment of personal pollution exposure after adjusting for the essential confounders. In the single-pollutant model, we observed the associations of NO₂ with sleep-disordered measures by decreasing the total sleep time, sleep efficiency, extending the time of wake after sleep onset, and the association of NO₂ with the increased risk of LAT OSA by around 15%. The two-pollutant model with both long-term and short-term exposures confirmed the most robust associations of long-term NO₂ exposure with sleep measures. An IQR increment of NO₂ averaged over the past year (6.0 ppb) decreased 3.32 min of total sleep time and 0.85% of sleep efficiency. Mitigating exposure to air pollution may improve sleep quality and reduce the risk of LAT OSA.

Invited Commentary: There's No Place Like Home-Integrating a Place-Based Approach to Understanding Sleep

Light exposure at night impedes sleep and shifts the circadian clock. An extensive body of literature has linked sleep deprivation and circadian misalignment with cardiac disease, cancer, mental health disorders, and other chronic illnesses, as well as more immediate risks, such as motor vehicle crashes and occupational injuries. In this issue of the Journal, Zhong et al. (Am J Epidemiol. 2022;191(9):1532-1539) build on this literature, finding that in a cohort of 50,000 California teachers, artificial light at night, noise, green space, and air pollution were all associated with sleep disturbances. Light, noise, air pollution, and the lack of green space are problems inequitably distributed across the population, concentrated among vulnerable populations in inner cities. Zhong et al. provide novel data on the manner in which these local environmental exposures drive sleep deprivation. Future research should explore the degree to which place-based disparities in sleep in turn drive disparities in short and long-term health. Addressing home-based sleep disparities could be an avenue to addressing systemic racism and achieving environmental justice.

Ambient air pollution and movement behaviours: A scoping review

This scoping review summarizes the literature about how ambient (outdoor) air pollution impacts movement behaviours (i.e., physical activity, sedentary behaviour, and sleep), or beliefs about movement behaviours. Of 6552 potential documents, 58 documents and 218 findings were included in the final synthesis. Most studies were from the United States and China, involved cross-sectional designs, and included mixed age groups. Overall, unfavourable changes/associations (i.e., decreased/lower physical activity, increased/higher sedentary-related behaviour, and decreased/lower sleep duration and quality) or no change/association in movement behaviours in relation to ambient air pollution were identified. Our findings suggest that more attention should be given to understanding the impact of ambient air pollution on movement behaviours in general and in diverse countries and vulnerable populations such as children or older adults.

Solid fuels use for cooking and sleep health in adults aged 45 years and older in China

Outdoor air pollution has been linked to poor sleep health, but limited studies have investigated the relationship between solid cooking fuels and sleep health in adults. Therefore, we analyzed data from the China Health and Retirement Survey (CHARLS), a national survey of about 17,000 residents aged over 45. Participants were restricted to those who participated in CHARLS 2011, 2013 and 2015 (n = 8,668). Sleep health was indicated by self-reported average sleep hours at night and the numbers of unrested days/week in CHARLS 2015. We analyzed cooking fuel types reported and assessed the duration of solid fuels usage as consistent (indicated use in all three surveys or 6 + years) or inconsistent use (indicated use in one or two surveys or 1-4 years). We found consistent use of solid fuels was associated with a shorter sleep duration (OR = 1.17 95% CI 1.01, 1.35 for ≤ 6 h vs. 7-9 h/day) and higher frequencies of feeling unrested (OR = 1.32 95% CI 1.12, 1.55 for ≥ 5 days/week vs. none) compared with cleaner fuels use. The associations for inconsistent solid fuels use and sleep health were in the similar direction but smaller in magnitude. Further research is needed to confirm our findings and evaluate the exposure impact of specific fuel types to inform intervention strategies.