Sleep-related breathing disorder in a Japanese occupational population and its association with hypertension-stratified analysis by obesity status

Sleep-related breathing disorder (SRBD) causes hypertension, and obesity has been highly associated with SRBD, which has become a serious health problem in young and middle-aged Japanese males. However, the relation between SRBD and hypertension considering the effects of obesity remains unknown. In this cross-sectional study, we examined the relationship between SRBD and hypertension, with consideration for the effects of obesity, in Japanese occupational population. Using 3% oxygen desaturation index (3%ODI) obtained by simplified polysomnography (PSG), participants were classified into low (0 ≤ 3%ODI < 5), medium (5 ≤ 3%ODI < 15), and high (15 ≤ 3%ODI) 3%ODI groups. We excluded employees who had not undergone medical examination with simplified PSG in the same year from 2012 to 2018. Logistic regression analysis was performed to calculate odds ratios for having hypertension according to 3%ODI levels. In total, 2532 employees were included. Among them, 25% and 4% were categorized into the medium and high 3%ODI groups, respectively. The odds ratio for hypertension increased significantly with higher 3%ODI levels after adjustment for age, sex, alcohol drinking status and smoking status (p for trend < 0.0001). However, further adjustment for obesity status (body mass index ≥ 25 kg/m2) attenuated the associations. When we performed the stratified analysis by obesity status, the odds ratio for hypertension increased significantly with higher 3%ODI only for non-obese individuals, with significant interaction (p for interaction = 0.014). Higher 3%ODI was significantly associated with higher prevalence of hypertension especially in non-obese participants, suggesting the importance of vigilance for the presence of SRBD even in non-obese individuals. We investigated the association between SRBD and hypertension considering the effects of obesity, which would suggest the need to keep in mind the presence of SRBD even in non-obese individuals.

The effect of continuous positive airway pressure (CPAP) on the quality of life in patients with multiple system atrophy

PURPOSE

To evaluate the effect of continuous positive airway pressure (CPAP) on the quality of life (QoL) in patients with multiple system atrophy (MSA) and their caregivers.

METHODS

We reviewed the electronic medical records of patients with MSA treated with CPAP (n = 15). After CPAP treatment, we checked the patient global impression of change (PGI-C) scale for sleep complaints and QoL for six patients who continued to use CPAP. QoL was also assessed for five caregivers of these patients.

RESULTS

A total of 15 patients (6 women) were included. The mean age was 63.6 ± 8.1 years old and the mean disease duration was 4.9 years. The mean duration of CPAP treatment was 22.1 ± 10.6 months and the average compliance was 90%. Three patients died during CPAP treatment, and two patients discontinued CPAP after tracheostomy. For six patients who continued to use CPAP, sleep complaints minimally improved. Five patients reported an improved QoL, and all five caregivers reported improved caregivers' QoL.

CONCLUSION

This study showed that the use of CPAP has a beneficial effect on sleep complaints and QoL of patients with MSA and their caregivers.

Translation and validation of the Arabic version of the sleep-related breathing disorder scale of the pediatric sleep questionnaire (PSQ-SRBD)

BACKGROUND/OBJECTIVES

The incidence of sleep-related breathing disorders is underestimated because polysomnography is required to confirm its diagnosis. The pediatric sleep questionnaire-sleep-related breathing disorder (PSQ-SRBD) scale is a self-reported questionnaire completed by a patient's guardian. There is no validated Arabic version of the PSQ-SRBD that can be used in the Arabic-speaking population. Therefore, we aimed to translate, validate, and culturally adapt the PSQ-SRBD scale. We also aimed to evaluate its psychometric properties for the diagnosis of obstructive sleep apnea (OSA).

METHODS

The cross-cultural adaptation method consisted of the following steps: forward-backward translation, appraisal of a sample of 72 children (aged between 2 and 16 years) by an expert group, and performing Cronbach's alpha coefficient testing, Spearman's rank correlation coefficient testing, Wilcoxon signed-rank testing, and sign testing. The reliability of the Arabic version of the PSQ-SRBD scale was assessed using a test-retest comparison, and a factor analysis of the items was used to verify construct validity. For statistical purposes, p-values <0.05 were considered to indicate significance.

RESULTS

All subscales had adequate internal consistency: 0.799 for snoring and breathing, 0.69 for sleepiness, 0.711 for behavioral problems, and 0.805 for the entire questionnaire. Comparing questionnaire responses administered 2 weeks apart revealed no statistically significant difference in total scores between the two groups (p-values >0.05 by Spearman's rank correlation coefficient test for all domains) and also no statistical difference among 20 out of 22 questions independently (p-value >0.05 by sign test). A factor analysis conducted to assess the structure of the Arabic-SRBD scale revealed good correlational patterns. The mean score before surgery was 0.464 ± 0.166, and this changed to 0.185 ± 0.142 after surgery with a reduction of 0.278 ± 0.184 which was statistically significant (p < 0.001).

CONCLUSION

The Arabic version of the PSQ-SRBD scale is a valid tool for the assessment of pediatric OSA patients and can be used to follow-up patients after surgery. Future research will determine this translated questionnaire's applicability.

[Research progress on the application of novel sensing technologies for sleep-related breathing disorder monitoring at home]

Sleep-related breathing disorder (SRBD) is a sleep disease with high incidence and many complications. However, patients are often unaware of their sickness. Therefore, SRBD harms health seriously. At present, home SRBD monitoring equipment is a popular research topic to help people get aware of their health conditions. This article fully compares recent state-of-art research results about home SRBD monitors to clarify the advantages and limitations of various sensing techniques. Furthermore, the direction of future research and commercialization is pointed out. According to the system design, novel home SRBD monitors can be divided into two types: wearable and unconstrained. The two types of monitors have their own advantages and disadvantages. The wearable devices are simple and portable, but they are not comfortable and durable enough. Meanwhile, the unconstrained devices are more unobtrusive and comfortable, but the supporting algorithms are complex to develop. At present, researches are mainly focused on system design and performance evaluation, while high performance algorithm and large-scale clinical trial need further research. This article can help researchers understand state-of-art research progresses on SRBD monitoring quickly and comprehensively and inspire their research and innovation ideas. Additionally, this article also summarizes the existing commercial sleep respiratory monitors, so as to promote the commercialization of novel home SRBD monitors that are still under research.

The impacts of ambient relative humidity and temperature on supine position-related obstructive sleep apnea in adults

Obstructive sleep apnea (OSA) is associated with seasonal variations. The objective of this study was to examine associations of ambient relative humidity (RH) and temperature on sleep parameters. We conducted a cross-sectional study by retrospectively recruiting 5204 adults from a sleep center in Taipei, Taiwan. Associations of 1-night polysomnography with ambient RH and temperature in 1-day, 7-day, 1-month, 6-month, and 1-year averages were examined using linear regression models and a mediation analysis. RH increase was associated with snoring index decrease and apnea/hypopnea index (AHI) increase. Temperature increase was associated with decreases in sleep efficiency and the AHI, and increases in the wake time after sleep onset and snoring index. RH increase was inversely associated with non-rapid eye movement (NREM) sleep stage I (N1), III (N3), and rapid eye movement (REM) sleep, but positively associated with the NREM sleep stage II (N2) stage. Temperature increase was associated with N1, N2, and N3 sleep. An increase in RH was associated with an increase in the arousal index and a decrease in the < 95% arterial oxygen saturation (SaO₂) among total, REM, and NREM sleep, whereas a temperature increase was associated with a decrease in the arousal index and an increase in < 95% SaO₂ among total, REM, and NREM sleep. An increase in RH was associated with increases in the time spent in a supine posture and the supine AHI. An increase in temperature was associated with decreases in the supine posture, supine AHI, and non-supine AHI. The N3 sleep stage was an important mediator in increasing the supine AHI with a long-term increase in RH. But the N1 and N2 sleep stages mediated a decrease in the supine AHI with an increase in RH. In conclusion, ambient RH and temperature were associated with alterations in sleep parameters in adults, which were mediated by the sleep cycle. An understanding of outdoor environments has important implications for diagnostic classifications in the supine dominance of OSA in adults.

Implications of Obstructive Sleep-related Breathing Disorder in Dentistry: Focus on Snoring and Obstructive Sleep Apnea

Obstructive sleep-related breathing disorder (SRBD) is an umbrella term that encompasses various types of upper airway dysfunctions during sleep characterized by increased respiratory effort secondary to snoring and/or increased upper airway resistance and pharyngeal collapse. Obstructive sleep apnea (OSA) is a representative SRBD that involves a significant decrease in or cessation of airflow despite the presence of respiratory effort. While snoring is considered a normal condition, it can cause serious noise disturbance to sleep partners and is considered a predictor of OSA. Snoring and OSA are highly correlated with obesity. SRBDs can lead to cardiovascular disease, hypertension, decreased quality of life, decreased work efficiency, daytime sleepiness, decreased neurocognitive activity, and psychological impairments. In dentistry, research on sleep problems has focused on temporomandibular disorder (TMD)/orofacial pain. The relationship between OSA and TMD/orofacial pain has been reported, but it is not clear whether it is a simple correlation or a causal relationship. Therefore, we aimed to review the causes of SRBDs including snoring and OSA and to review and infer the relationship between these SRBDs and TMD/orofacial pain. The effects of snoring and OSA extend beyond sleep disturbances and are worthy of future research, especially with regard to TMD.

Visceral Fat Area by Abdominal Bioelectrical Impedance Analysis as a Risk of Obstructive Sleep Apnea

This is the first study to evaluate directly visceral fat area (VFA) using a visceral fat (VF) meter by the abdominal bioelectrical impedance analysis (A-BIA) method in obstructive sleep apnea (OSA) patients diagnosed with polysomnography (PSG). The purpose of this study is to clarify (1) whether VFA measurement using a VF meter by the A-BIA method is possible even in a private clinic without burdening patients and staff and (2) how much VFA affects OSA compared to body mass index (BMI). Even without a computed tomography scan, which is the gold standard for VFA measurement, a VF meter could analyze patients by the A-BIA method and easily measure VFA. Therefore, it could be used safely even in a private sleep clinic, with very little burden on the patients and the medical staff. We investigated the association between OSA and VFA in 133 OSA patients. Multiple regression analysis revealed that VFA (β = 0.28; P = 0.020) was a stronger coexisting factor for OSA than age, male gender, or BMI (β = 0.26; P = 0.032) in all OSA patients. In the OSA patients with VF accumulation, only VFA was a significant component of OSA severity (β = 0.36; P = 0.006). The A-BIA method instrument could become a useful device for the evaluation of VF accumulation in OSA patients in private sleep clinics. VF accumulation should be recognized as an important risk factor as well as a known risk factor for OSA.

Development of a pediatric obstructive sleep apnea triage algorithm

INTRODUCTION

Diagnosis and treatment of obstructive sleep apnea (OSA) in children is often delayed due to the high prevalence and limited physician and sleep testing resources. As a result, children may be referred to multiple specialties, such as pediatric sleep medicine and pediatric otolaryngology, resulting in long waitlists.

METHOD

We used data from our pediatric OSA clinic to identify predictors of tonsillectomy and/or adenoidectomy (AT). Before being seen in the clinic, parents completed the Pediatric Sleep Questionnaire (PSQ) and screening questionnaires for restless leg syndrome (RLS), nasal rhinitis, and gastroesophageal reflux disease (GERD). Tonsil size data were obtained from patient charts and graded using the Brodsky-five grade scale. Children completed an overnight oximetry study before being seen in the clinic, and a McGill oximetry score (MOS) was assigned based on the number and depth of oxygen desaturations. Logistic regression, controlling for otolaryngology physician, was used to identify significant predictors of AT. Three triage algorithms were subsequently generated based on the univariate and multivariate results to predict AT.

RESULTS

From the OSA cohort, there were 469 eligible children (47% female, mean age = 8.19 years, SD = 3.59), with 89% of children reported snoring. Significant predictors of AT in univariate analysis included tonsil size and four PSQ questions, (1) struggles to breathe at night, (2) apneas, (3) daytime mouth breathing, and (4) AM dry mouth. The first triage algorithm, only using the four PSQ questions, had an odds ratio (OR) of 4.02 for predicting AT (sensitivity = 0.28, specificity = 0.91). Using only tonsil size, the second algorithm had an OR to predict AT of 9.11 (sensitivity = 0.72, specificity = 0.78). The third algorithm, where MOS was used to stratify risk for AT among those children with 2+ tonsils, had the same OR, sensitivity, and specificity as the tonsil-only algorithm.

CONCLUSION

Tonsil size was the strongest predictor of AT, while oximetry helped stratify individual risk for AT. We recommend that referral letters for snoring children include graded tonsil size to aid in the triage based on our findings. Children with 2+ tonsil sizes should be triaged to otolaryngology, while the remainder should be referred to a pediatric sleep specialist.

Waking EEG functional connectivity in middle-aged and older adults with obstructive sleep apnea

OBJECTIVES

The present study aimed at investigating changes in waking electroencephalography (EEG), most specifically regarding spectral power and functional connectivity, in middle-aged and older adults with obstructive sleep apnea (OSA). We also explored whether changes in spectral power or functional connectivity are associated with polysomnographic characteristics and/or neuropsychological performance.

METHODS

In sum, 19 OSA subjects (apnea-hypopnea index ≥ 20, age: 63.6 ± 6.4) and 22 controls (apnea-hypopnea index ≤ 10, age: 63.6 ± 6.7) underwent a full night of in-laboratory polysomnography (PSG) followed by a waking EEG and a neuropsychological assessment. Waking EEG spectral power and imaginary coherence were compared between groups for all EEG frequency bands and scalp regions. Correlation analyses were performed between selected waking EEG variables, polysomnographic parameters and neuropsychological performance.

RESULTS

No group difference was observed for EEG spectral power for any frequency band. Regarding the imaginary coherence, when compared to controls, OSA subjects showed decreased EEG connectivity between frontal and temporal regions in theta and alpha bands as well as increased connectivity between frontal and parietal regions in delta and beta 1 bands. In the OSA group, these changes in connectivity correlated with lower sleep efficiency, lower total sleep time and higher apnea-hypopnea index. No relationship was found with neuropsychological performance.

CONCLUSIONS

Contrary to spectral power, imaginary coherence was sensitive enough to detect changes in brain function in middle-aged and older subjects with OSA when compared to controls. Whether these changes in cerebral connectivity predict cognitive decline needs to be investigated longitudinally.

Impact of sleep-related breathing disorder on motor and non-motor symptoms in multiple system atrophy

INTRODUCTION

Although several studies suggested that sleep-related breathing disorder (SRBD) is a frequent symptom of multiple system atrophy (MSA), whether SRBD has influence on the motor and non-motor symptoms of MSA is unknown.

METHODS

A total of 40 MSA patients and 40 healthy volunteers (HVs) underwent video-polysomnography (PSG) in the current study. All the MSA individuals were assessed using the Epworth Sleepiness Scale (ESS), Unified Multiple-System Atrophy Rating Scale (UMSARS), Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale, Frontal assessment battery (FAB), Parkinson's Disease Questionnaire-39 (PDQ-39), and the Montreal Cognitive Assessment (MoCA).

RESULTS

We found apnea-hypopnea index (AHI) of the MSA patients recorded by PSG was 16.4 ± 20.2. SRBD was found in 65% of the MSA patients (26/40), which was significantly higher than HVs (8/40, 20%) (p = 0.0001). Compared to the MSA patients without SRBD, MSA individuals with SRBD showed higher total UMSARS, UMSARS-II, FAB, and HAMD scores, more frequent occurrence of excessive daytime sleepiness, hypopneas, longer mean times for hypopneas, and obstructive sleep apnea (OSA), as well as longer time for OSA. This study suggested that SRBD is frequently seen in MSA patients.

CONCLUSION

MSA individuals with SRBD are prone to be severe motor deficits, depression, frontal lobe dysfunction, and excessive daytime sleepiness.

Sleep-related breathing disorders in patients with tumors in the head and neck region

BACKGROUND

Sleep disturbance is a prominent complaint of cancer patients. Most studies have focused on insomnia and cancer-related fatigue. Obstructive sleep apnea (OSA) has been reported in small studies and case reports.

METHODS

In a retrospective review of patients who underwent formal sleep evaluation and polysomnography (PSG) from 2006 to 2011, 56 patients with tumors in the head and neck region were identified. Clinical characteristics, sleep-related history, and PSG data were reviewed.

RESULTS

Most patients had active cancer (80%), and the majority had squamous pathology (68%). Prominent symptoms included daytime fatigue (93%), daytime sleepiness (89%), and snoring (82%). Comorbid conditions primarily included hypertension (46%) and hypothyroidism (34%). Significant sleep-related breathing disorder was noted in 93% of patients, and 84% met clinical criteria for OSA. A male predominance (77%) was noted, and patients were not obese (body mass index <30 kg/m(2) in 52%). The majority of patients (79%) underwent radiation prior to sleep study, of which 88% had OSA, and in the group without prior radiation, 67% had OSA. Adherence to positive airway pressure (PAP) therapy was slightly better when compared with the general population. A subset of patients with persistent hypoxia despite advanced forms of PAP required tracheostomy. Multivariate analysis revealed that patients with active disease and radiation prior to PSG were more likely to have OSA.

CONCLUSION

Sleep-related breathing disorder was common in patients with tumors in the head and neck region referred for evaluation of sleep disruption, and most met clinical criteria for OSA. Daytime fatigue and sleepiness were the most common complaints. OSA was prevalent in male patients, and most with OSA were not obese. Architectural distortion from the malignancy and/or treatment may predispose these patients to OSA by altering anatomic and neural factors. A heightened clinical suspicion for sleep-related breathing disorder and referral to a sleep specialist would be beneficial for patients with these complaints.