Occupation and Obstructive Sleep Apnea: A Meta-Analysis

Is exposure to chemical pollutants associated with sleep outcomes? A systematic review

Environmental exposures may influence sleep; however, the contributions of environmental chemical pollutants to sleep health have not been systematically investigated. We conducted a systematic review to identify, evaluate, summarize, and synthesize the existing evidence between chemical pollutants (air pollution, exposures related to the Gulf War and other conflicts, endocrine disruptors, metals, pesticides, solvents) and dimensions of sleep health (architecture, duration, quality, timing) and disorders (sleeping pill use, insomnia, sleep-disordered breathing)). Of the 204 included studies, results were mixed; however, the synthesized evidence suggested associations between particulate matter, exposures related to the Gulf War, dioxin and dioxin-like compounds, and pesticide exposure with worse sleep quality; exposures related to the Gulf War, aluminum, and mercury with insomnia and impaired sleep maintenance; and associations between tobacco smoke exposure with insomnia and sleep-disordered breathing, particularly in pediatric populations. Possible mechanisms relate to cholinergic signaling, neurotransmission, and inflammation. Chemical pollutants are likely key determinants of sleep health and disorders. Future studies should aim to evaluate environmental exposures on sleep across the lifespan, with a particular focus on developmental windows and biological mechanisms, as well as in historically marginalized or excluded populations.

Association between occupational exposure to chemical or physical factors and sleep disturbance: An analysis of the fifth Korean Working Conditions Survey

OBJECTIVE

A range of risk factors in occupational environments can negatively affect the sleep of workers. Although psychosocial factors have been emphasized in various studies, few have reported on the relationship between physical or chemical exposure in the workplace and sleep disturbances. Thus, this study aimed to investigate the relationship between occupational exposure to physical or chemical factors and sleep disturbances.

DESIGN

Cross-sectional study.

SETTING

Data from the fifth Korean Working Conditions Survey (KWCS).

PARTICIPANTS

The target population of the fifth KWCS was economically active individuals aged 15 years or older in all Korean households in 2017, resulting in a total study population of 50,176 participants. After excluding the unemployed, full-time students, homemakers, and the retired, 36,996 employees were included in the current study.

MEASUREMENTS

Exposure to occupational physical or chemical risk factors was assessed by multiplying the exposure scales of physical or chemical risk factors and weekly working hours. Sleep disturbance was estimated using the Minimal Insomnia Symptom Scale.

RESULTS

In the fully adjusted logistic regression model, exposure to the following risk factors was positively associated with sleep disturbance: vibration (odds ratio [OR], 1.74)); noise (OR, 2.28); high temperatures (OR, 2.43); low temperatures (OR, 2.51); smoke, fume, and dust (OR, 2.12); vapors of solvents or thinners (OR, 3.78); chemical substances (OR, 3.78); and environmental smoking (OR, 5.03).

CONCLUSIONS

The results of this study provide evidence of a relationship between occupational exposure to physical or chemical factors and sleep disturbances.

What is the association between secondhand smoke (SHS) and possible obstructive sleep apnea: a meta-analysis

BACKGROUND

Association between smoking and sleep apnea is well-known from previous studies. However, the influence of secondhand smoke (SHS), which is a potential risk factor of obstructive sleep apnea (OSA), remains unclear. Our aim was to investigate the relationship between SHS and OSA using a meta-analysis.

MATERIALS AND METHODS

For the meta-analysis, searches were performed in MEDLINE, EMBASE, and Web of Science databases on January 10, 2022, by combining various keywords including "SHS exposure" and "OSA". Data were extracted using defined inclusion and exclusion criteria. Fixed-effects model meta-analyses were used to pool risk ratio (RR) estimates with their 95% confidence intervals (CI). I² was used to assess heterogeneity. Moreover, we performed subgroup meta-analyses of children-adults, and smoker fathers and mothers.

RESULTS

In total, 267 articles were obtained through an electronic search. Twenty-six articles were included in our analysis according to the inclusion and exclusion criteria. We found evidence of an association between SHS exposure and possible OSA (RR 1.64, 95% CI 1.44-1.88). The results of the subgroup analyses showed that children passive smokers (RR 1.84, 95% CI 1.60-2.13) were at greater risks of possible OSA than adult passive smokers (RR 1.35, 95% CI 1.21-1.50). Also, significant differences were observed in mothers with smoking exposure (RR 2.61, 95% CI 1.62-4.21, p < 0.0001), as well as in fathers with smoking exposure (RR 2.15, 95% CI 0.98-4.72, p = 0.06).

SHORT CONCLUSION

Our meta-analysis confirmed that SHS exposure is significantly associated with OSA. In the subgroup analyses, the association of SHS and possible OSA was significant in both children and adults, as well as in smoker mothers and fathers.

Factors Associated With Undiagnosed Obstructive Sleep Apnea in Overweight and Obese High-Tech Employees: A Multisite Cross-Sectional Study

Background: Being overweight or obese is regarded as crucial risk factors for obstructive sleep apnea (OSA). Objectives: This study aimed to determine the influencing factors of overweight and obese employees with OSA in high-tech workplaces. Methods: A cross-sectional study design was employed. A total of 491 overweight and obese participants were recruited from a large-scale electronics industry. The Chinese version of Pittsburgh Sleep Quality Index, the Epworth Sleep Scale, and a portable sleep monitoring device were used for data collection. Logistic regression analysis was conducted to identify the factors affecting overweight and obese employees with OSA. This study was conducted from August 2019 to July 2020. Results: 60.5% of the overweight and obese participants were found to have OSA, of which 58.9% had mild and 18.5% had severe OSA, respectively. The results showed that age, neck circumference, snoring, and habitual drinking were the crucial factors affecting OSA. Remarkably, age and snoring times showed a significant correlation in predicting OSA of different severities. Neck circumference was an independent risk factor for moderate and severe OSA. Conclusion: More than 60% of the overweight and obese high-tech workplace employees were found to have OSA. We found that the older the age, the larger the neck circumference, a higher number of snoring instances, and drinking were important risk factors for predicting OSA in overweight high-tech employees. The healthcare providers should actively educate OSA-related information for employees in the workplace, and promote high-risk OSA groups to adopt screening based on at-home sleep apparatus.

The Incidence of Cancer Is Increased in Hospitalized Adult Patients With Obstructive Sleep Apnea in China: A Retrospective Cohort Study

Background

The association between obstructive sleep apnea (OSA) and the incidence and mortality of cancer remain unclear, especially in Asian populations. Thus, this study was conducted to explore the relationship between OSA and the incidence and mortality of cancer in hospitalized patients.

Methods

This retrospective cohort study evaluated inpatients from Guangdong Provincial People’s Hospital for suspected OSA between January 2005 and December 2015. Cancer incidence, all-cause mortality, and cancer mortality and were determined using data from the hospital information system and Centers for Disease Control. Between-group comparisons were carried out by performing a chi-square test and analysis of variance. Kaplan–Meier analysis and the Cox proportional risk model were applied to investigate the association between OSA and cancer incidence and mortality.

Results

Of the 4,623 hospitalized patients included, 3,786 (81.9%) patients were diagnosed with OSA. After a median follow-up of 9.1 years (interquartile range, 9.79–11.44), the incidence of cancer was 6.6% (251/3,786), with lung cancer having the highest incidence at 1.6% (60/3,786). The mortality rate of OSA patients was higher than that of non-OSA patients (16.83% vs.12.78%, p=0.008), but the relationship between apnea-hypopnea index (AHI), oxygen saturation less than 90% (TSat90), and cancer mortality was not statistically significant (p>0.05).The mortality rate for all types of cancer was 2.8% (105/3,786), with lung cancer having the highest mortality rate at 0.8% (32/3,786). The cumulative incidence of cancer in the severe OSA group was 8.2%, which was higher than that in the normal, mild, and moderate OSA groups (P=0.010). Further, the Cox proportional risk regression model showed a progressive enhancement in the risk of cancer incidence as the AHI increased (adjusted hazard ratio [HR]: 1.009 [95% confidence interval (CI): 1.003–1.016], P=0.005). Based on subgroup analysis, the risk of cancer increased as the AHI increased in patients aged <65 years (adjusted HR: 1.019 [95% CI: 1.007–1.031], P=0.002). In addition, the cancer incidence was significantly higher in the severe OSA group than in the normal, mild, and moderate OSA groups (adjusted HR: 2.825 [95% CI: 1.358–5.878], P=0.019).

Conclusion

The incidence of cancer is higher in patients with OSA than in non-OSA patients and is significantly positively associated with the severity of OSA. Particularly, for OSA patients aged <65 years, lung cancer is the main cause of death in those with new-onset cancer. Mortality was higher in OSA patients than in non-OSA patients.

The association between shift work and possible obstructive sleep apnea: a systematic review and meta-analysis

BACKGROUND

Shift work is a workschedule, since industrial era and some employees work in shift. It causes a desynchronization of the biological clock with consequences on sleep amount and quality, such as insomnia and easy fatigue. Obstructive sleep apnea (OSA) is one of the sleep problems that are getting more and more attention, but studies on the association between shift work and OSA were rare. Herein, we aimed to conduct a systematic review and meta-analysis to investigate the association between shift work and possible OSA.

METHODS

This study was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We queried PubMed, Embase, and Web of Science databases using a related set of keywords. The inclusion criteria were as follows: (1) participants were adult employees hired by a company or organization; (2) exposure was shift work; and (3) outcome was possible OSA according to examination or assessment.

RESULTS

We included six studies in the systematic review and five studies were selected for further meta-analysis. A random-effects model showed an association of shift work with a small, non-significant increase in possible OSA cases (pooled prevalence relative risk = 1.05; 95% CI 0.85-1.30; p = 0.65). This association occurred in both healthcare and non-healthcare workers group.

CONCLUSION

The association between shift work and possible OSA remains inconclusive and could be small if not negligible. Future studies should assess the association between specific work schedules and specific OSA definitions.

TRIAL REGISTRATION NUMBER

PROSPERO ID: CRD42020156837.

Occupational exposures and genetic susceptibility to occupational exposures are related to sickness absence in the Lifelines cohort study

In this cross-sectional study, we investigated the association between occupational exposures and sickness absence (SA), the mediating role of respiratory symptoms, and whether genetic susceptibility to SA upon occupational exposures exists. Logistic regression was used to examine associations and structural equation modelling was used for mediation analyses. Genetic susceptibility was investigated by including interactions between occupational exposures and 11 candidate single nucleotide polymorphisms (SNPs). Biological dust, mineral dust, and pesticides exposure were associated with a lower prevalence of any SA (OR (95% CI) = 0.72 (0.58-0.89), 0.88 (0.78-0.99), and 0.70 (0.55-0.89), respectively) while gases/fumes exposure was associated with a higher prevalence of long-term SA (1.46 (1.11-1.91)). Subjects exposed to solvents and metals had a higher prevalence of any (1.14 (1.03-1.26) and 1.68 (1.26-2.24)) and long-term SA (1.26 (1.08-1.46) and 1.75 (1.15-2.67)). Chronic cough and chronic phlegm mediated the association between high gases/fumes exposure and long-term SA. Two of 11 SNPs investigated had a positive interaction with exposure on SA and one SNP negatively interacted with exposure on SA. Exposure to metals and gases/fumes showed a clear dose-response relationship with a higher prevalence of long-term SA; contrary, exposure to pesticides and biological/mineral dust showed a protective effect on any SA. Respiratory symptoms mediated the association between occupational exposures and SA. Moreover, gene-by-exposure interactions exist.

Sleep Characteristics and Measures of Glucose Metabolism in Blacks: The Jackson Heart Study

Background Characterizing associations of sleep characteristics with blood-glucose-level factors among blacks may clarify the underlying mechanisms of impaired glucose metabolism and help identify treatment targets to prevent diabetes mellitus in blacks. Methods and Results Cross-sectional analyses were conducted in 789 blacks who completed home sleep apnea testing and 7-day wrist actigraphy in 2012-2016. Sleep-disordered breathing measurements included respiratory event index associated with 4% oxygen desaturation and minimum oxygen saturation. Sleep patterns on actigraphy included fragmented sleep indices. Associations between sleep characteristics (8 exposures) and measures of glucose metabolism (3 outcomes) were determined using multivariable linear regression. Mean (SD) age of the participants was 63 (11) years; 581 (74%) were women; 198 (25%) were diabetes mellitus, and 158 (20%) were taking antihyperglycemic medication. After multivariable adjustment, including antihyperglycemic medication use, the betas (95% CI) for fasting glucose and hemoglobin A1c, respectively, for each SD higher level were 0.13 (0.02, 0.24) mmol/L and 1.11 (0.42, 1.79) mmol/mol for respiratory event index associated with 4% oxygen desaturation and 0.16 (0.05, 0.27) mmol/L and 0.77 (0.10, 1.43) mmol/mol for fragmented sleep indices. Among 589 participants without diabetes mellitus, the betas (95% CI) for homeostatic model assessment of insulin resistance for each SD higher level were 1.09 (1.03, 1.16) for respiratory event index associated with 4% oxygen desaturation, 0.90 (0.85, 0.96) for minimum oxygen saturation, and 1.07 (1.01, 1.13) for fragmented sleep indices. Conclusions Sleep-disordered breathing, overnight hypoxemia, and sleep fragmentation were associated with higher blood glucose levels among blacks.

Effects of alertness management training on sleepiness among long-haul truck drivers: A randomized controlled trial

Education is a frequently recommended remedy for driver sleepiness in occupational settings, although not many studies have examined its usefulness. To date, there are no previous on-road randomized controlled trials investigating the benefits of training on sleepiness among employees working in road transport. To examine the effects of an educational intervention on long-haul truck drivers' sleepiness at the wheel, amount of sleep between work shifts, and use of efficient sleepiness countermeasures (SCM) in association with night and non-night shift, a total of 53 truck drivers operating from southern Finland were allocated into an intervention and a control group using a stratified randomization method (allocation ratio for intervention and control groups 32:21, respectively). The intervention group received a 3.5-hour alertness management training followed by a two-month consultation period and motivational self-evaluation tasks two and 4-5 months after the training, while the control group had an opportunity to utilize their usual statutory occupational health care services. The outcomes were measured under drivers' natural working and shift conditions over a period of two weeks before and after the intervention using unobtrusive data-collection methods including the Karolinska Sleepiness Scale measuring on-duty sleepiness, a combination of actigraphy and a sleep-log measuring sleep between duty hours, and self-report questionnaire items measuring the use of SCMs while on duty. The data analysis followed a per-protocol analysis. Results of the multilevel regression models showed no significant intervention-related improvements in driver sleepiness, prior sleep, or use of SCMs while working on night and early morning shifts compared to day and/or evening shifts. The current study failed to provide support for a feasible non-recurrent alertness-management training being effective remedy for driver sleepiness in occupational settings. These results cannot, however, be interpreted as evidence against alertness management training in general but propose that driver education is not a sufficient measure as such to alleviate driver sleepiness.