Risk factors associated with habitual snoring and sleep-disordered breathing in a multi-ethnic Asian population: a population-based study

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

A cross-sectional study on the relationship between electronic cigarette and combustible cigarette use with obstructive sleep apnea among U.S. adults: result from NHANES 2015-2018

BACKGROUND

To explore whether the use of e-cigarettes and conventional cigarettes affects the prevalence of obstructive sleep apnea (OSA) in adults.

METHODS

Complete records of smoking and sleep about OSA from the 2015-2018 National Health and Nutrition Examination Survey. The adults were divided into four groups: noncurrent smokers, current electronic cigarettes (e-cigarette) users only, current conventional cigarettes (c-cigarette) users only, and dual users. OSA was assessed by three main signs and symptoms from the questionnaire. Multivariable logistic regression after adjusting for covariates was conducted to investigate the association of OSA with different smoking patterns.

RESULTS

Among the 11,248 participants, the prevalence of OSA was higher among smokers compared to non-smokers (P < 0.0001). In a stratified analysis of smoke manners, the results showed that an increased prevalence of OSA with c-cigarette use alone (OR = 1.38, 95% CI = 1.17-1.63) and dual-use (OR = 1.78, 95% CI = 1.37-2.32) compared to non-smoking participants, while there was no significant difference with e-cigarette use (OR = 0.84, 95% CI = 0.52-1.37). Multivariate logistic regression analysis showed the prevalence of OSA is highest in dual users (OR = 1.93, 95% CI = 1.39-2.69) than non-smokers.

CONCLUSION

Our findings indicate the prevalence of OSA was higher in c-cigarette smokers than in non-smokers, while there was no significant difference in the prevalence of OSA between e-cigarette smokers and non-smokers. Dual users had the highest prevalence for OSA compared to c-cigarette smokers, e-cigarette smokers and non-smokers.

Long-term benefits of a new oral appliance on adult snoring: a trend analysis

Background: Snoring constitutes a worldwide public health concern that may be associated with daytime fatigue, endothelial dysfunction, vascular injury, stroke, cardiovascular diseases, and diabetes among female patients. This study explored the effects of the so-called Lin Oral Appliance (LOA) on Taiwanese adults’ snoring rates.Methods: A time series analysis was conducted to examine the associations between LOAs’ tongue compressors of different lengths, and snoring rates were calculated using the SnoreClock app. The LOA comprises 2 components: custom-made dental braces and tongue compressors of adjustable lengths; different versions had different-length compressors.Results: Our multiple linear regression time-series model revealed the effects of the LOA on snoring rates. The results indicated the following: i) LOA tongue compressor lengths of 1 and 2.5 cm (LOA-1 and LOA-2.5, respectively) were associated with reduced snoring rates; ii) sleep durations of 5.5-7.5 h and daytime sleepiness were associated with increased snoring rates; and iii) among participants with snoring rates above 10%, the snoring rates observed 1-7 days before a given day constituted a significant factor influencing snoring rates on the given day.Conclusions: We discovered that the LOA could reduce snoring rates and that the 2.5-cm compressor length in the LOA produced the best results.

Effects of a novel oral appliance on snoring in adults: A pilot study

AbstractBackground/purpose

Oral appliances (OAs) have been recommended as alternatives for adult patients with obstructive sleep apnea who are intolerant of continuous positive airway pressure therapy. The aim of this study was to explore the effect on snoring rates among adult patients through use of a novel OA termed the Lin OA (LOA, airflow-interference-type nasal congestion relieving and snore-ceasing oral appliance).

Materials and methods

The LOA consist of two parts: dental braces and a fixed tongue compressor. The compressor lengths range from 0.5 cm to 3.5 cm across versions. Patients used the LOA during sleep and the SnoreClock smartphone application recorded their snoring rates.

Results

A total of 4920 recordings (4239 recordings from 34 men, 681 recordings from 8 women) were used for the analysis. The recordings were sorted in accordance with the applied length of the LOA tongue compressor (0.5–3.5 cm, LOA-0.5, LOA-1 and LOA-3.5), and participants not using the LOA were denoted as the LOA-0 group. The women had higher snoring rates in the LOA-0, LOA-0.5 to LOA-2 groups, but lower snoring rates in the LOA-3 group than men by the univariate analysis. The snoring rates were significantly reduced by a mean of 5.04% with every 1 cm increase in tongue compressor length. Continuous LOA use resulted in snoring rate reductions of 0.02% per day by the random intercept model of the linear regression.

Conclusion

Use of this novel LOA may significantly reduce snoring rates by 5.04% with each 1 cm increase in tongue compressor length.

A scoping review of racial/ethnic disparities in sleep

BACKGROUND

Despite remarkable achievements in ensuring health equity, racial/ethnic disparities in sleep still persist and are emerging as a major area of concern. Accumulating evidence has not yet been well characterized from a broad perspective. We conducted a scoping review of studies on sleep disparities by race/ethnicity to summarize characteristics of existing studies and identify evidence gaps.

METHODS

We searched PubMed, CINAHL, PsycINFO, and Web of Science databases for studies of racial/ethnic disparities in sleep. Studies that met inclusion criteria were retrieved and organized in a data charting form by study design, sleep measuring methods, sleep features, and racial/ethnic comparisons.

RESULTS

One hundred sixteen studies were included in this review. Most studies focused on disparities between Whites and Blacks. Disproportionately fewer studies examined disparities for Hispanic, Asian, and other racial/ethnic groups. Self-reported sleep was most frequently used. Sleep duration, overall sleep quality, and sleep disordered breathing were frequently studied, whereas other features including sleep efficiency, latency, continuity, and architecture were understudied, particularly in racial minority groups in the US. Current study findings on racial/ethnic disparities in most of sleep features is mixed and inconclusive.

CONCLUSIONS

This review identified significant evidence gaps in racial/ethnic disparities research on sleep. Our results suggest a need for more studies examining diverse sleep features using standardized and robust measuring methods for more valid comparisons of sleep health in diverse race/ethnicity groups.

Validation of snoring detection using a smartphone app

Purpose

Snoring is closely related to obstructive sleep apnea in adults. The increasing abundance and availability of smartphone technology has facilitated the examination and monitoring of snoring at home through snoring apps. However, the accuracy of snoring detection by snoring apps is unclear. This study explored the snoring detection accuracy of Snore Clock—a paid snoring detection app for smartphones.

Methods

Snoring rates were detected by smartphones that had been installed with the paid app Snore Clock. The app provides information on the following variables: sleep duration, snoring duration, snoring loudness (in dB), maximum snoring loudness (in dB), and snoring duration rate (%). In brief, we first reviewed the snoring rates detected by Snore Clock; thereafter, an ear, nose, and throat specialist reviewed the actual snoring rates by using the playback of the app recordings.

Results

In total, the 201 snoring records of 11 patients were analyzed. Snoring rates measured by Snore Clock and those measured manually were closely correlated (r = 0.907). The mean snoring detection accuracy rate of Snore Clock was 95%, with a positive predictive value, negative predictive value, sensitivity, and specificity of 65% ± 35%, 97% ± 4%, 78% ± 25%, and 97% ± 4%, respectively. However, the higher the snoring rates, the higher were the false-negative rates for the app.

Conclusion

Snore Clock is compatible with various brands of smartphones and has a high predictive value for snoring. Based on the strong correlation between Snore Clock and manual approaches for snoring detection, these findings have validated that Snore Clock has the capacity for at-home snoring detection.

The Efficacy of Diode Laser Palatoplasty on Patients with Troublesome Snoring

INTRODUCTION

Simple Snoring is low frequency sound without obstructive sleep apnea, produced mainly from vibration of the upper airway wall in the soft palate; it can be bothersome and may causes social problems. So the aim of this study is an attempt for relieving simple snoring though, stiffening the soft palate via transoral diode laser palatoplasty.

MATERIALS AND METHODS

Forty six adult patients with socially troublesome snoring were recruited in this stuy. Adequately history was taken to rule out witnessed evidence of obstructive sleep apnea. Then full otolaryngological examination, with soft palate vibration grading assessment by Muller maneuver were followed, consequently the eligible patients were underwent transoral 810 nm diode laser palatoplasty under local anesthesia and followed-up 6 months post-operatively.

RESULTS

The loudness of subjective snoring assessed by visual analogue score (VAS) was relieved from 6.6 to 2.4 and by Muller maneuver was improved from 2.7 to 1.9, and for the frequency from 2.1 Hz to 0.3 Hz, and from 2.4 Hz to 0.55 Hz for the duration pre to post-operative with P value of 0.75 to 0.023 respectively, So the overall frequencies of improvement of snoring loudness results had revealed a total improvement (no snoring) were detected in 4 patients, and moderate improvement had been found in 30 patients, while mild improvement of snoring had been seen in 10 patients, however about 2 patents got no benefit from the surgery.

CONCLUSION

Stiffening of the soft palate by diode laser had shown to be significantly beneficial in relieving the snoring intensity as it had a positive impact on its subjective loudness, frequency and duration.

The association between exposure to second-hand smoke and sleep disturbances: A systematic review and meta-analysis

OBJECTIVE

To investigate the association between second-hand smoke (SHS) exposure and sleep disturbances by systematically reviewing the literature base and to quantify this association by conducting a meta-analysis.

METHOD

We did a systematic search of five databases- PubMed, Embase, CINAHL Plus, Web of Science - Core Collection, and Google Scholar. The primary outcomes were short sleep duration (SSD), poor sleep quality (PSQ), and excessive daytime sleepiness (EDS).

RESULT

Our systematic search yielded a total of 1623 studies. However, 12 studies qualified for qualitative synthesis and 11 studies (12 surveys) with adequate information were included in the meta-analysis involving 730,808 participants. All the studies were cross-sectional. We found an association between SHS exposure and SSD [pooled OR: 1.20 (95% CI, 1.09-1.33; p = 0.0003; I²= 68%), N = 7]; EDS [pooled OR: 1.07 (95% CI, 1.01-1.13; p = 0.02; I² = 0%), N = 4]; and PSQ [pooled OR: 1.12 (95% CI, 1.01-1.23; p = 0.03; I² = 79%), N = 10]. Subgroup analyses suggest significant association between SHS exposure and PSQ among adolescents. However, no such association was observed among adults. In addition, no significant association was observed between PSQ and SHS exposure when biomarker was used to identify SHS exposure.

CONCLUSION

This study is the first systematic review and meta-analysis to examine the association between SHS exposure and sleep outcomes. Self-reported exposure to SHS is positively associated with SSD, EDS, and PSQ, although the effects are modest. Further studies with robust methodology to ascertain exposure information are warranted to further elucidate the relationship between SHS exposure and sleep disturbances.

Habitual snoring, adiposity measures and risk of type 2 diabetes in 0.5 million Chinese adults: a 10-year cohort

OBJECTIVES

The present study aimed to examine whether habitual snoring was independently associated with risk of type 2 diabetes among Chinese adults, and to assess the role that adiposity measures play in the snoring-diabetes association, as well as to evaluate the joint influence of snoring and adiposity measures on diabetes.

RESEARCH DESIGN AND METHODS

The China Kadoorie Biobank study recruited 512 715 adults aged 30-79 years from 10 regions in China during 2004 and 2008. Data from 482 413 participants without baseline diabetes were analyzed in the present study. Autoregressive cross-lagged panel analysis was used to assess the longitudinal relationship between adiposity measures and habitual snoring. Cox proportional hazards models were used to examine the association between habitual snoring and diabetes risk.

RESULTS

Both higher body mass index and waist circumference were associated with higher risks of subsequent habitual snoring, whereas no reverse association was detected. A total of 16 479 type 2 diabetes cases were observed during a 10-year follow-up. Habitual snoring was independently associated with 12% (95% CI 6% to 18%) and 14% (95% CI 9% to 19%) higher risks of diabetes among men and women, respectively. Habitual snorers who had general obesity or central obesity were about twice as likely to develop diabetes as non-snorers at the lowest levels of adiposity measures.

CONCLUSION

Habitual snoring was independently associated with a higher risk of type 2 diabetes among Chinese adults. It is important to maintain both a healthy weight and a normal waist circumference to prevent or alleviate habitual snoring and ultimately prevent diabetes among Chinese adults.

The prevalence of high risk obstructive sleep apnoea among patients with type 2 diabetes in Jordan

OBJECTIVE

To estimate the prevalence of Obstructive Sleep Apnea (OSA) among patients with type 2 Diabetes Mellitus (T2DM) in Jordan, and to explore the association between sleep apnea and clinical and demographic variables.

METHOD

A cross-sectional study was carried out from the 1st of November 2011 to the 1st of February 2012 on 1143 patients with T2DM (aged 30-90 years) at the National Center for Diabetes, Endocrinology, and Genetics (NCDEG). The center is considered to be the only referral center in the country and accordingly, the patients represent the population in different parts of the country. All participants completed the Arabic version of the Berlin Questionnaire and were categorized as either low or high-risk patients for OSA.

RESULTS

A total of 1143 patients with T2DM were included in this study. There were 587 (51.4%) males and 556 (48.6%) females. The findings showed that 554 (48.5%) patients were at high risk for OSA and 589 (51.5%) were low risk for OSA. Logistic regression analysis revealed that age, smoking, and neck circumference were significantly correlated with high risk for OSA. The clinical and demographic variables were also collected for analysis.

CONCLUSIONS

The study found that high risk for OSA was highly prevalent among Jordanian patients with T2DM and that age, smoking and neck circumference were significantly correlated with OSA. Health care providers should be made aware of the high prevalence of sleep problems affecting patients with diabetes and should consider the appropriate screening and treatment for these patients, therefore improving their quality of life.

A nationwide, cross-sectional survey on unusual sleep postures and sleep-disordered breathing-related symptoms in people with Down syndrome

BACKGROUND

People with Down syndrome (DS) often have sleep-disordered breathing (SDB). Unusual sleep postures, such as leaning forward and sitting, are observed in people with DS. This study aimed to clarify the prevalence of unusual sleep postures and their relationships with SDB-related symptoms (SDB-RSs), such as snoring, witnessed apnoea, nocturnal awakening and excessive daytime sleepiness.

METHODS

A questionnaire, including demographic characteristics and the presence of unusual sleep postures, as well as SDB-RSs, was completed by 1149 parents of people with DS from Japan.

RESULTS

Unusual sleep postures were recorded in 483 (42.0%) people with DS. These participants were significantly younger and had a history of low muscle tone more frequently than people without unusual sleep postures. In all ages, the leaning forward posture was more frequent than sitting. People with DS with unusual sleep postures suffered from SDB-RSs. Those who slept in the sitting posture had more frequent SDB-RSs than did those who slept with the leaning forward posture. Snoring, witnessed apnoea and nocturnal awakening were observed in 73.6, 27.2 and 58.2% of participants, respectively. Snoring increased with aging. Witnessed apnoea was more common in males and in those with hypothyroidism than in females and in those without hypothyroidism.

CONCLUSIONS

Our study shows that there is a close relationship between unusual sleep postures and SDB-RSs. We recommend that all people with DS with unusual sleep postures should be checked for the presence of SDB.

Which oropharyngeal factors are significant risk factors for obstructive sleep apnea? An age-matched study and dentist perspectives

OBJECTIVE

Obstructive sleep apnea (OSA) is a common sleep breathing disorder. Untreated OSA may lead to a number of cardiovascular complications. Dentists may play an important role in OSA detection by conducting careful oral examinations. This study focused on the correlation of oral anatomical features in Thai patients who presented with OSA.

METHODS

We conducted a prospective comparative study at a sleep/hypertension clinic and a dental clinic at Khon Kaen University in Thailand. Patients with OSA were enrolled in the study, along with age-matched patients with non-OSA (controls). Baseline characteristics, clinical data, and oropharyngeal data of all patients were compared between the two groups. Oropharyngeal measurements included tongue size, torus mandibularis, Mallampati classification, palatal space, and lateral pharyngeal wall area. Multivariate logistic regression analysis was used to identify the factors associated with OSA.

RESULTS

During the study period, there were 156 patients who met the study criteria; 78 were patients with OSA and the other 78 were healthy control subjects. In the OSA group, there were 43 males with a mean age of 53 (standard deviation 12.29) years and a mean BMI of 30.86 kg/mm(2). There were 37 males in the control group with a mean age of 50 (standard deviation 12.04) years and a mean BMI of 24.03 kg/mm(2). According to multivariate logistic analysis, three factors were perfectly associated with OSA, including torus mandibularis class 6, narrow lateral pharyngeal wall, and Mallampati class 4. There were two other significant factors associated with having OSA, namely, BMI and Mallampati classification. The adjusted odds ratios (95% confidence interval) of these two factors were 1.445 (1.017, 2.052) and 5.040 (1.655, 15.358), respectively.

CONCLUSION

Dentists may play an important role in the detection of OSA in patients with high BMI through careful oropharyngeal examination in routine dental treatment. A large torus mandibularis, Mallampati class 4, and a narrow lateral pharyngeal wall are important anatomical risk factors for OSA.

Correlation between the oropharyngo-laryngoscopic findings and the severity of obstructive sleep apnea

OBJECTIVE

To correlate anatomical and functional changes of the oral cavity, pharynx and larynx to the severity of obstructive sleep apnea syndrome (OSAS).

METHODS

We conducted a cross-sectional study of 66 patients of both genders, aged between 21 and 59 years old with complaints of snoring and / or apnea. All underwent full clinical evaluation, including physical examination, nasolarybgoscopy and polisonography. We classified individuals into groups by the value of the apnea-hypopnea index (AHI), calculated measures of association and analyzed differences by the Kruskal-Wallis and chi-square tests.

RESULTS

all patients with obesity type 2 had OSAS. We found a relationship between the uvula projection during nasoendoscopy and OSAS (OR: 4.9; p-value: 0.008; CI: 1.25-22.9). In addition, there was a major strength of association between the circular shape of the pharynx and the presence of moderate or severe OSAS (OR: 9.4, p-value: 0.002), although the CI was wide (1.80-53.13). The septal deviation and lower turbinate hypertrophy were the most frequent nasal alterations, however unrelated to gravity. Nasal obstruction was four times more common in patients without daytime sleepiness. The other craniofacial anatomical changes were not predictors for the occurrence of OSAS.

CONCLUSION

oral, pharyngeal and laryngeal disorders participate in the pathophysiology of OSAS. The completion of the endoscopic examination is of great value to the evaluation of these patients.

Validation of overnight oximetry to diagnose patients with moderate to severe obstructive sleep apnea

Background

Polysomnography (PSG) is treated as the gold standard for diagnosing obstructive sleep apnea (OSA). However, it is labor-intensive, time-consuming, and expensive. This study evaluates validity of overnight pulse oximetry as a diagnostic tool for moderate to severe OSA patients.

Methods

A total of 699 patients with possible OSA were recruited for overnight oximetry and PSG examination at the Sleep Center of a University Hospital from Jan. 2004 to Dec. 2005. By excluding 23 patients with poor oximetry recording, poor EEG signals, or respiratory artifacts resulting in a total recording time less than 3 hours; 12 patients with total sleeping time (TST) less than 1 hour, possibly because of insomnia; and 48 patients whose ages less than 20 or more than 85 years old, data of 616 patients were used for further study. By further considering 76 patients with TST < 4 h, a group of 540 patients with TST ≥ 4 h was used to study the effect of insufficient sleeping time. Alice 4 PSG recorder (Respironics Inc., USA) was used to monitor patients with suspected OSA and to record their PSG data. After statistical analysis and feature selection, models built based on support vector machine (SVM) were then used to diagnose moderate and moderate to severe OSA patients with a threshold of AHI = 30 and AHI = 15, respectively.

Results

The SVM models designed based on the oxyhemoglobin desaturation index (ODI) derived from oximetry measurements provided an accuracy of 90.42-90.55%, a sensitivity of 89.36-89.87%, a specificity of 91.08-93.05%, and an area under ROC curve (AUC) of 0.953-0.957 for the diagnosis of severe OSA patients; as well as achieved an accuracy of 87.33-87.77%, a sensitivity of 87.71-88.53%, a specificity of 86.38-86.56%, and an AUC of 0.921-0.924 for the diagnosis of moderate to severe OSA patients. The predictive outcome of ODI to diagnose severe OSA patients is better than to diagnose moderate to severe OSA patients.

Conclusions

Overnight pulse oximetry provides satisfactory diagnostic performance in detecting severe OSA patients. Home-styled oximetry may be a tool for severe OSA diagnosis.

Factors associated with reported snoring among elderly patients attending the geriatric centre in Nigeria

INTRODUCTION

Snoring is the major symptom of sleep disordered breathing (SDB) which is of immense public health importance. It is associated with some morbidities and mortality in the elderly. Few studies have addressed this problem in the elderly Nigerians.

METHODS

Cross-sectional study of 843 elderly patients at the Geriatric Centre, University College Hospital, Ibadan, Nigeria. Data were collected on the following candidate variables which may be associated with snoring such as socio-demographic characteristics, morbidities, lifestyle habits and functional disability using Katz index. Anthropometric measurements such as body mass index and neck, waist and hip circumferences were taken. Statistical analysis was done with SPSS 17.

RESULTS

The point prevalence of reported snoring was 31.2%. Habitual snoring was reported by 24.8%. Snoring was significantly associated with obesity, moderate to severe oropharyngeal crowding, wide neck and waist circumferences in both sexes. Logistic regression analysis showed wide neck circumference (OR = 6.005; 95%CI= 2.150-16.770) among the males and obesity (OR = 2.028; 95%CI= 1.344-3.061) and moderate to severe oropharyngeal crowding (OR = 1.639; 95%CI= 1.057-2.543) in the females to be the most significant factors associated with snoring.

CONCLUSION

The high prevalence of snoring among elderly patients in Nigeria calls for concerted effort by healthcare workers to educate the elderly.

Cephalometric norms for the upper airway of 12-year-old Chinese children

Objective

To establish cephalometric norms for the upper airway of 12-year-old Chinese children, and to assess these norms with regard to gender, age, ethnicity and other craniofacial structures.

Methods

Lateral cephalograms were obtained from a random sample of 425 12-year-old Chinese children (224 boys and 201 girls) to establish the Chinese norms, and from a matched group of 108 12-year-old Caucasian children (61 boys and 47 girls) as an ethnic comparison. Published data on the upper airway norms of Chinese adults were used to make age comparisons. Nine upper airway and 14 craniofacial variables were measured.

Results

Chinese boys tended to have a thicker soft palate (P = 0.008), and less depth in the retropalatal (P = 0.011), retroglossal (P = 0.034) and hypopharyngeal (P < 0.001) pharynx than Chinese girls, whereas no gender dimorphism was found in Caucasian children. Ethnic differences were found in the depth of the retroglossal oropharynx in both genders and the position of the hyoid bone in boys. Compared with Chinese adults, the overall size of the upper airway in Chinese children was smaller. The mandibular body length and the craniocervical inclination were found to be statistically significantly, albeit weakly correlated with upper airway variables.

Conclusions

Cephalometric norms for the upper airway of Chinese 12-year-old children were established, indicating gender-specific differences, and some ethnic differences were found in comparison with those of 12-year-old Caucasian children. An association between the mandibular body length and the craniocervical inclination with upper airway variables was also noticeable.

Simple snoring: not quite so simple after all?

Simple snoring (SS), in the absence of obstructive sleep apnoea (OSA), is a common problem, yet our understanding of its causes and consequences is incomplete. Our understanding is blurred by the lack of consistency in the definition of snoring, methods of assessment, and degree of concomitant complaints. Further, it remains contentious whether SS is independently associated with daytime sleepiness, or adverse health outcomes including cardiovascular disease and metabolic syndrome. Regardless of this lack of clarity, it is likely that SS exists on one end of a continuum, with OSA at its polar end. This possibility highlights the necessity of considering an otherwise 'annoying' complaint, as a serious risk factor for the development and progression of sleep apnoea, and consequent poor health outcomes. In this review, we: 1) highlight variation in prevalence estimates of snoring; 2) review the literature surrounding the distinctions between SS, upper airway resistance syndrome (UARS) and OSA; 3) present the risk factors for SS, in as far as it is distinguishable from UARS and OSA; and 4) describe common correlates of snoring, including cardiovascular disease, metabolic syndrome, and daytime sleepiness.

Self-reported snoring and carotid atherosclerosis in middle-aged and older adults: the Korean Multi-Rural Communities Cohort Study

Background

We investigated the relation of self-reported snoring with carotid intima-media thickness (IMT) and plaque in community-dwelling middle-aged and older adults.

Methods

In total, 7330 community-dwelling subjects in the Korean Multi-Rural Communities Cohort Study were included in the analysis. Common carotid artery IMT (CCA-IMT) and plaque were evaluated by high-resolution B-mode ultrasonography. Snoring status was evaluated using a structured interview.

Results

Snorers had a significantly greater average CCA-IMT than non-snorers (0.726 vs 0.713 mm; P < 0.001), after adjusting for age and gender. The odds ratios (OR) for high CCA-IMT (fifth quintile) were significantly higher for snorers than for non-snorers in multivariate-adjusted analysis (OR 1.25, 95% confidence interval [CI] 1.10–1.42). However, there was no significant relationship between snoring and carotid plaques.

Conclusions

Our data suggest that self-reported snoring is significantly associated with increased IMT, but not with the presence of plaques. These findings suggest that early screening and intervention for snoring in the general population are needed to prevent adverse cardiovascular events.

Prevalence of obstructive sleep apnea in Asian adults: a systematic review of the literature

Background

Obstructive sleep apnea (OSA) is a common disease, affecting approximately 2% of women and 4% of men residing in Western communities. No systematically reviewed data are available about the prevalence of this disease in Asia, the most heavily populated continent.

Methods

PubMed/Medline, Scopus and Google Scholar were searched for articles published from 1993 to May 2012 that reported the prevalence of OSA diagnosed via sleep monitoring and the prevalence of patients at risk for OSA as assessed by symptomatology and/or sleep questionnaires. We have also searched abstract database of major pulmonary and sleep scientific societies for relevant abstracts presented from 2010 to 2012. The following inclusion criteria were used: articles published in English, age ≥ 18 years, ≥ 100 participants in studies using sleep monitoring for the diagnosis of OSA, ≥ 300 participants in studies using questionnaires to detect patients at high risk for OSA. Exclusion criteria: duplicate publications, studies reporting the prevalence of central sleep apnea only, hospital based studies as well as studies assessing OSA prevalence among patients with resistant arterial hypertension, chronic kidney disease, heart failure and in patients with concomitant neurological disease.

Results

Twenty four articles were found to meet the inclusion criteria, covering 47,957 subjects (26,042 men and 21,915 women) and four relevant abstracts were noted. OSA prevalence ranged from 3.7% to 97.3%. Male gender, older age, a higher BMI and waist to hip ratio, greater neck circumference, arterial hypertension, smoking, snoring and daytime sleepiness were associated with OSA. Sample size, difference between the populations studied and the fact that some works included patients with a high pre-test probability of OSA explain the difference in prevalence rates.

Conclusion

This systematic review highlights the lack of data regarding the prevalence of OSA in Asians. Only a few studies provide an approximate estimate of the OSA burden in some Asian communities.

Addressing obstructive sleep apnea in the emergency department

BACKGROUND

Obstructive sleep apnea (OSA) is a prevalent, serious disease that is under-recognized and under-treated. It results from a combination of increased pharyngeal collapsibility and impaired compensatory pharyngeal muscle dilator activity. OSA causes serious morbidity and mortality. OSA is also a public health problem in that it is an independent cause of car crashes, at great cost to society in dollars and lives. OSA is conservatively estimated to affect 2-4% of Americans; however, recent estimates are much higher.

OBJECTIVES

To educate emergency physicians on the pathophysiology, epidemiology, diagnosis, and management of OSA and discuss diagnostic approaches and recommendations that can be made from the emergency department (ED).

DISCUSSION

Emergency physicians can play an important role in the recognition and referral of patients at risk for OSA. A focused history and physical examination or the use of a structured evaluation can identify patients at risk for OSA. In addition to referring patients at risk for OSA for further diagnostic work-up, emergency physicians can offer recommendations such as weight loss, moderation of alcohol use and certain medications, and smoking cessation.

CONCLUSION

OSA is a common disease in the United States that is under-recognized and under-treated. ED patients who do not regularly see a primary care provider or have no primary care provider are particularly at risk for undiagnosed OSA. Emergency physicians can play an important role in recognizing patients at risk for OSA, referring them for further diagnostic work-up, and offering recommendations from the ED.

Risk factors for snoring among Japanese men and women: a community-based cross-sectional study

PURPOSE

This study seeks to examine risk factors for snoring, a major symptom of sleep-disordered breathing (SDB) because the evidence is limited in Asian populations.

METHODS

Subjects for the present cross-sectional study were 3,138 men and 5,345 women aged 35–79 years from three communities in Japan who participated in the Circulatory Risk in Communities Study. The data on snoring frequency and cardiovascular health were obtained during annual cardiovascular surveys between 2000 and 2005. The logistic regression model was used to estimate the odds ratios (ORs) for snoring associated with body mass index (BMI), alcohol consumption, and other cardiovascular risk factors.

RESULTS

The prevalence of almost everyday snoring was 24% among men and 10% among women. After adjustments for age, community, cigarette smoking, alcohol consumption, and for women, menopausal status, the multivariable-adjusted ORs for everyday snoring in the highest versus lowest quartiles of BMI categories were 3.4 (95% confidence interval (CI): 2.6–4.4) for men and 3.9 (2.8–5.4) for women. The respective ORs in ≥23 g ethanol per day versus never-drinkers categories were 1.4 (1.1–1.8) and 3.1 (1.8–5.3) and those in ≥20 cigarettes versus never-smokers categories were 1.4 (1.0–1.8) and 1.9 (0.9–3.7). The associations of alcohol consumption and cigarette smoking with everyday snoring were stronger for BMI<25 kg/m2 than BMI≥25 kg/m2 in both sexes.

CONCLUSION

BMI, alcohol consumption, and cigarette smoking were positively associated with habitual snoring for both men and women, especially in nonoverweight persons.

Obstructive sleep apnoea and schizophrenia: a primer for psychiatrists

Alam A, Chengappa KNR. Obstructive sleep apnoea and schizophrenia: a primer for psychiatrists Objective: The main objective of this review is to improve psychiatric clinician awareness of obstructive sleep apnoea (OSA) and its potential consequences in patients with schizophrenia. This article will also discuss the diagnosis and treatment options for OSA while considering the significant role psychiatrists can play in facilitating the diagnosis and treatment of OSA.

DATA SOURCES

Ovid, Medline and PsychInfo databases were searched for articles between 1960 and 2010. Search terms used were Sleep apnoea or apnoea and schizophrenia or psychosis. The number of articles retrieved was 38. Articles were carefully reviewed for any data pertinent to OSA in patients with schizophrenia.

CONCLUSIONS

OSA is a common disorder that is frequently unrecognised. As a chronic breathing condition, OSA is associated with adverse health outcomes and high mortality. OSA may co-occur with schizophrenia or evolve over time, especially with weight gain. The diagnosis should be considered whenever a patient presents with risk factors or clinical manifestations that are highly suggestive of OSA. Those who report snoring, daytime sleepiness and are obese or have a large neck circumference should be considered for an OSA diagnosis. Appropriate diagnosis and treatment of OSA can reduce daytime sleepiness, improve cardiovascular and other medical conditions, as well as reduce mortality. Psychiatrists can play very important role in suspecting OSA in their patients and making the initial referral. Furthermore, behavioural management, especially promoting weight loss and smoking cessation, are effective components of OSA treatment that psychiatrists are positioned to facilitate with their patients.

Diagnostic characteristics of clinical prediction models for obstructive sleep apnea in different clinic populations

PURPOSE

As predictive factors and their diagnostic values are affected by the characteristics of the population studied, clinical prediction model for obstructive sleep apnea (OSA) may exhibit different diagnostic characteristics in different populations. We aimed to compare the diagnostic characteristics of clinical prediction models developed in two different populations.

METHODS

One hundred seventeen consecutive clinic patients (group 1) were evaluated to develop a clinical prediction model for OSA (local model). The diagnostic characteristics of this local model were compared with those of a foreign model by applying both models to another group of 52 patients who were referred to the same clinic (group 2). All patients underwent overnight polysomnography.

RESULTS

The local model had an area under receiver operator characteristics curve of 79%. A cutoff of 0.6 was associated with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 77.9%, 72.5%, 84.5%, and 63.0%, respectively. The overall diagnostic accuracy, sensitivity, specificity, PPV, and NPV of the local model using data from patients in group 2 were 69.0%, 78.1%, 45.0%, 69.4%, and 56.3%, respectively. The foreign model had an overall diagnostic accuracy of 64.0% when applied to data from patients in group 2. At the optimal cutoff of 17, the foreign model was associated with sensitivity of 38.2%, specificity of 83.3%, NPV of 41.7% and PPV of 81.3%.

CONCLUSIONS

Clinical prediction model for OSA derived from a foreign population exhibits markedly different diagnostic characteristics from one that is developed locally, even though the overall accuracy is similar. Our findings challenge the predictive usefulness and the external validity of clinical prediction models.

Prevalence and associated risk factors of sleep-disordered breathing symptoms in young and middle-aged Pakistani employed adults

PURPOSE

The objective of this study was to evaluate the prevalence of self-reported sleep-disordered breathing (SDB symptoms and its associated risk factors in Pakistani employed adults.

METHODS

Full-time employees (n = 3470) of a medical university were evaluated. Self-administered questionnaire elicited information about demographic data, symptoms of SDB, smoking and alcohol use, presence of nasal congestion, family history of snoring, and included the Epworth Sleepiness Scale. Prevalence of self-reported snoring and of combined SDB symptoms (snoring plus at least one other SDB symptom) was evaluated. Regression analyses were used to assess risk factors associated with self-reported snoring and combined SDB symptoms.

RESULTS

Among the 2,497 (72%) responders, prevalence of self-reported snoring was 32%, and combined SDB symptoms 25%. A higher prevalence of snoring and combined SDB symptoms in male gender diminished with age. In univariate analysis, the odds of snoring was higher with age >or=35 yrs (odds ratio (OR) 2.6, confidence interval (CI) 2.2-3.2), body mass index >or=23 (OR 2.6, CI 2.2-3.1), and collar size above 40 cm (OR 2.7, CI 2.3-3.3). Self-reported nasal blockage (OR 1.9, CI 1.6-2.2) and family history of snoring (OR 2.9, 2.5-3.5) were other risk factors. In logistic regression analysis, significant risk factors for SDB symptoms were age, body mass index, collar size, nasal blockage, and family history of snoring. Male gender, smoking and alcohol were not significant risk factors for SDB symptoms.

CONCLUSION

The prevalence of SDB symptoms in Pakistani employed adults was comparable to Western populations. However, male gender and smoking were not significant risk factors for SDB symptoms.

A placebo-controlled trial of modafinil for nicotine dependence

BACKGROUND

Nicotine deprivation symptoms, including fatigue and attentional deficits, predict relapse following smoking cessation. Modafinil (Provigil), a wakefulness medication shown to have efficacy for the treatment of cocaine addiction, was tested as a novel therapy for nicotine dependence in a double-blind placebo-controlled trial.

METHODS

One hundred and fifty-seven treatment-seeking smokers received brief smoking cessation counseling and were randomized to: (1) 8 weeks of modafinil (200mg/day), or (2) 8 weeks of placebo. The primary outcome was biochemically verified 7-day point prevalence abstinence at the end of treatment (EOT). Secondary outcomes included cigarette smoking rate and post-quit nicotine deprivation symptoms (e.g., negative affect, withdrawal).

RESULTS

In this interim study analysis, EOT quit rates did not differ between treatment arms (42% for placebo vs. 34% for modafinil; OR=0.67 [0.34-1.31], p=0.24). Further, from the target quit date to EOT, the daily smoking rate was 44% higher among non-abstainers in the modafinil arm, compared to non-abstainers in the placebo arm (IRR=1.44, CI95=1.09-1.89, p<0.01). Modafinil-treated participants also reported greater increases in negative affect and withdrawal symptoms, vs. participants randomized to placebo (ps<0.05).

CONCLUSIONS

These data do not support the use of modafinil for the treatment of nicotine dependence and, as a consequence, this trial was discontinued. Cigarette smoking should be considered when modafinil is prescribed, particularly among those with psychiatric conditions that have high comorbidity with nicotine dependence.

The epidemiology of adult obstructive sleep apnea

Obstructive sleep apnea is a chronic condition characterized by frequent episodes of upper airway collapse during sleep. Its effect on nocturnal sleep quality and ensuing daytime fatigue and sleepiness are widely acknowledged. Increasingly, obstructive sleep apnea is also being recognized as an independent risk factor for several clinical consequences, including systemic hypertension, cardiovascular disease, stroke, and abnormal glucose metabolism. Estimates of disease prevalence are in the range of 3% to 7%, with certain subgroups of the population bearing higher risk. Factors that increase vulnerability for the disorder include age, male sex, obesity, family history, menopause, craniofacial abnormalities, and certain health behaviors such as cigarette smoking and alcohol use. Despite the numerous advancements in our understanding of the pathogenesis and clinical consequences of the disorder, a majority of those affected remain undiagnosed. Simple queries of the patient or bed-partner for the symptoms and signs of the disorder, namely, loud snoring, observed apneas, and daytime sleepiness, would help identify those in need of further diagnostic evaluation. The primary objective of this article is to review some of the epidemiologic aspects of obstructive sleep apnea in adults.

Prevalence and risk factors for obstructive sleep apnea in a multiethnic population of patients presenting for bariatric surgery in Singapore

INTRODUCTION

Obesity is becoming more prevalent world wide. Bariatric surgery is one treatment option for patients with severe or morbid obesity. There have been few comprehensive studies examining prevalence and risk factors for obstructive sleep apnea (OSA) in the multiracial Singaporean bariatric surgery population.

METHODS

We performed full polysomnography on 176 consecutive patients undergoing assessment for bariatric surgery. Questionnaires regarding snoring, the presence of witnessed apneas and the Epworth Sleepiness Scale (ESS) were administered. Anthropometric and demographic measurements include age, sex, race, body mass index (BMI) and neck circumference.

RESULTS

The prevalence of OSA was 72%, and 49% of the 176 patients had an AHI >= 15. There was a male predominance of OSA (X(2) = 29.7; p<0.001). OSA subjects had larger neck circumference (43.9 +/- 4.5 vs. 39.4 cm +/- 3.3; p<0.001) and higher BMI (43.1 +/- 7.6 vs. 39.1 +/- 5.4 kg/m(2); p<0.001). The neck circumference (OR = 1.37; p<0.001), presence of snoring (OR = 8.25; p<0.001) and an ESS >10 (OR = 3.24; p = 0.03) were significant independent predictors of an AHI >= 15. A neck circumference of 43 cm had an 80% sensitivity and 83% specificity for predicting an AHI >= 15.

CONCLUSIONS

OSA is common amongst Singaporeans undergoing evaluation for bariatric surgery, with a high prevalence of moderate and severe disease. An increased neck circumference is a strong independent predictor for an AHI >= 15, with a neck circumference of greater than 43 cm being a sensitive and specific predictor. Race was not found to be a risk factor.

Risk factors and correlates of snoring and observed apnea

BACKGROUND AND PURPOSE

Risk factors and correlates of snoring and observed apnea in the population are not well known. This study aimed to assess risk factors and correlates of snoring and observed apnea.

METHODS

Parents and grandparents of students from 20 randomly selected primary schools in urban and rural areas of Kirikkale, Turkey were asked about respiratory diseases, psychological distress and sleep-related disorders, using the Respiratory Questionnaire, Hospital Anxiety and Depression (HAD) scale and Sleep Questionnaire, respectively, which were returned by their children.

RESULTS

Out of 13,225 parents and grandparents of primary school students 12,270 returned the questionnaires, for an overall response rate of 92.7%. Snoring and the observed apnea were more prevalent among subjects from rural than those from urban areas (52.6% vs. 46.6%, odds ratio (OR): 1.2, p<0.001 and 16.2% vs. 10.1%, OR: 1.7, p<0.001, respectively). Exposure to biomass smoke and smoking were associated with an increased risk of snoring and observed apnea, after adjusting for gender, age, body mass index, income and education in the multivariate linear model. In all subjects, increases in performance ability, daytime sleepiness, psychological distress and dyspnea scores observed in categories indicating increases in snoring intensity and observed apnea frequency constituted a trend but did always not reach statistical significance. Lastly, prevalence of traffic accidents, falling asleep at the wheel and morning headaches increased with the increments of snoring intensity and apnea frequency.

CONCLUSIONS

Exposure to biomass smoke in rural areas may account for the higher prevalence of snoring and observed apnea. Snoring intensity and observed apnea frequency may increase prevalence of traffic accidents along with many unfavorable symptoms.

Perceived job stress and sleep-related breathing disturbance in Japanese male workers

To examine the association of job stress with sleep-related breathing disturbance (SBD), a cross-sectional sample of 1940 males aged 17-83 (mean 45) years in 292 small and medium-sized enterprises in Japan were surveyed by means of a self-administered questionnaire. Perceived job stress was evaluated by the Japanese version of the Generic Job Stress Questionnaire developed by the US National Institute for Occupational Safety and Health, which included 13 job stress variables. Participants were divided into thirds according to their job stress scores. SBD was assessed by the question "Have you ever felt difficulty breathing during sleep or has anyone in your family told you that you have such difficulty?" SBD was defined as presence of symptoms more than once a month. Risk of SBD through job stress was estimated using logistic regression with odds ratios (ORs) and 95% confidence intervals (CIs) as measures of association. Prevalence of study-defined SBD was 6.7%. Participants who perceived the lowest level of social support from supervisors, and highest levels of job future ambiguity, interpersonal conflict at the workplace, job dissatisfaction, variance in workload, and quantitative workload had significantly increased risk of SBD after adjusting for potential confounders. High depressive symptoms, as measured by Center for Epidemiologic Studies Depression scale scores of 16 or higher, were also significantly associated with increased SDB. Although the results should be considered preliminary because of the self-reporting and cross-sectional design, data suggest that exposure to high job stress could be a possible risk factor for developing or aggravating SBD. Results also indicate that job stress should be considered when evaluating SBD in occupational and clinical settings.

Snoring noise pollution—the need for objective quantification of annoyance, regulatory guidelines and mandatory therapy for snoring

Habitual snoring without episodes of apnea or hypoventilation and without respiratory related arousals is considered to be annoying and without any need for treatment. However, studies seem to suggest an enormous psychosocial impact of annoyance for the bed partner. Apart from subjective questionnaires there still exists no generally accepted mode of measurement that can describe snoring objectively. We therefore adapted methods developed for environmental medicine and established a new snore score using psycho-acoustic parameters. For quantification of snoring noise we conducted nocturnal measurements in 19 habitual snorers. Free-field snore sounds were acquired with two low-cost non-contact microphones and transferred to a PC (sampling frequency 11 kHz). The data were recorded, analysed and stored automatically using a MATLAB script. Following the analysis of sound characteristics and levels, the score was computed from relevant parameters containing the rating level (L(R)), maximum level, two percentile levels for frequent maxima (L(5)S; L(1)) and snoring time. The determined values substantially exceeded the prescribed limits defined by WHO noise guidelines, and mainly affected the equivalent continuous sound exposure level, rating level and the immission standard values of brief noise peaks, whose maximum was exceeded by up to 32 dB(A). The Berlin snore score illustrated the objective acoustic annoyance on a scale from 0 to 100. It allows inter-individual comparison and objectifies the need for therapy. The clinical applicability of evaluating the reduction of snoring after surgical therapy is discussed exemplarily. The presented measuring method was found to be suitable for quantifying snoring noise and can be easily integrated into existing polysomnographic applications. In the case of habitual snoring with objective evidence of psychosocially disturbing acoustic annoyance, health fund providers should assume the costs of mandatory medical therapy.

Obesity, ethnicity, and sleep-disordered breathing: medical and health policy implications

The obesity epidemic in the United States is a major health problem, which poses im-mediate and long-term health risks with potential for significant reduction in life expectancy if not curtailed. Despite affecting all segments of the population, minorities carry a relatively larger burden of the obesity threat. Obesity is a major risk factor for develop-ing obstructive sleep apnea and the metabolic syndrome, which are associated with increased cardiovascular and cerebrovascular morbidity and mortality. This article discusses the implications of the obesity trend on the prevalence of obstructive sleep ap-nea and health, highlights ethnic differences, reviews the resultant economic implications, and suggests public health and health policy initiatives that may be beneficial in stemming the obesity scourge.

Ethnicity and obstructive sleep apnoea

There is a scarcity of adult prevalence studies of OSA outside the Caucasian populations of North America, Europe and Australia, and comparisons have been complicated by methodological differences in sleep study settings, respiratory events definition, measured risk factors and clinical outcomes, and the lack of objective parameters for the measurement of ethnicity itself. Comparing studies with the same methodological design and respiratory events definition, recent large-scale prevalence studies from Hong Kong, Korea and India show similar OSA rates to populations of mainly Caucasian composition. OSA is a very complex disorder determined by several phenotypes such as obesity, craniofacial structure and abnormalities in neuromuscular and ventilatory control. Genetics may partially explain some of the ethnic clustering of these phenotypes, modulated by cultural and environmental factors. The exact contribution of these component phenotypes to overall OSA risk will be determined by their varying prevalence and relative risk conferred across ethnic groups. For lesser degrees of obesity, Asians are at risk for a more severe degree of illness compared with Caucasians. Inter-ethnic studies suggests that African-American ethnicity may also be a significant risk factor for OSA. The increased prevalences of OSA among American Indians and Hispanic adults, and increased severity among Pacific Islanders and Maoris, were mainly explained by increased obesity parameters. Most cephalometric studies have largely been conducted without specific regard to ethnicity and comparisons of findings across studies have been mainly limited by differences in sampling methods and the varying selection and definition of measured cephalometric variables. The limited number of studies with inter-ethnic comparative data suggest cephalometric variables and their degree of contribution to OSA vary across ethnic groups.