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1.  Habitual Snoring in school-aged children: environmental and biological predictors 
Respiratory Research  2010;11(1):144.
Background
Habitual snoring, a prominent symptom of sleep-disordered breathing, is an important indicator for a number of health problems in children. Compared to adults, large epidemiological studies on childhood habitual snoring and associated predisposing factors are extremely scarce. The present study aimed to assess the prevalence and associated factors of habitual snoring among Chinese school-aged children.
Methods
A random sample of 20,152 children aged 5.08 to 11.99 years old participated in a cross-sectional survey, which was conducted in eight cities of China. Parent-administrated questionnaires were used to collect information on children's snoring frequency and the possible correlates.
Results
The prevalence of habitual snoring was 12.0% (14.5% for boys vs. 9.5% for girls) in our sampled children. Following factors were associated with an increased risk for habitual snoring: lower family income (adjusted odds ratio [OR] = 1.46), lower father's education (OR = 1.38 and 1.14 for middle school or under and high school of educational level, respectively), breastfeeding duration < 6 months (OR = 1.17), pregnancy maternal smoking (OR = 1.51), obesity (OR = 1.50), overweight (OR = 1.35), several respiratory problems associated with atopy and infection, such as chronic/allergic rhinitis (OR = 1.94), asthma (OR = 1.43), adenotonsillar hypertrophy (OR = 2.17), and chronic otitis media (OR = 1.31), and family history of habitual snoring (OR = 1.70).
Conclusion
The prevalence of habitual snoring in Chinese children was similar to that observed in other countries. The potential predisposing factors covered socioeconomic characteristics, environmental exposures, chronic health problems, and family susceptibility. Compared to socioeconomic status and family susceptibility, environmental exposures and chronic health problems had greater impact, indicating childhood habitual snoring could be partly prevented by health promotion and environmental intervention.
doi:10.1186/1465-9921-11-144
PMCID: PMC2967531  PMID: 20955625
2.  Increased Cerebral Blood Flow Velocity in Children with Mild Sleep-Disordered Breathing 
Pediatrics  2006;118(4):e1100-e1108.
Objective
Sleep-disordered breathing describes a spectrum of upper airway obstruction in sleep from simple primary snoring, estimated to affect 10% of preschool children, to the syndrome of obstructive sleep apnea. Emerging evidence has challenged previous assumptions that primary snoring is benign. A recent report identified reduced attention and higher levels of social problems and anxiety/depressive symptoms in snoring children compared with controls. Uncertainty persists regarding clinical thresholds for medical or surgical intervention in sleep-disordered breathing, underlining the need to better understand the pathophysiology of this condition. Adults with sleep-disordered breathing have an increased risk of cerebrovascular disease independent of atherosclerotic risk factors. There has been little focus on cerebrovascular function in children with sleep-disordered breathing, although this would seem an important line of investigation, because studies have identified abnormalities of the systemic vasculature. Raised cerebral blood flow velocities on transcranial Doppler, compatible with raised blood flow and/or vascular narrowing, are associated with neuropsychological deficits in children with sickle cell disease, a condition in which sleep-disordered breathing is common. We hypothesized that there would be cerebral blood flow velocity differences in sleep-disordered breathing children without sickle cell disease that might contribute to the association with neuropsychological deficits.
Design
Thirty-one snoring children aged 3 to 7 years were recruited from adenotonsillectomy waiting lists, and 17 control children were identified through a local Sunday school or as siblings of cases. Children with craniofacial abnormalities, neuromuscular disorders, moderate or severe learning disabilities, chronic respiratory/cardiac conditions, or allergic rhinitis were excluded. Severity of sleep-disordered breathing in snoring children was categorized by attended polysomnography. Weight, height, and head circumference were measured in all of the children. BMI and occipitofrontal circumference z scores were computed. Resting systolic and diastolic blood pressure were obtained. Both sleep-disordered breathing children and the age- and BMI-similar controls were assessed using the Behavior Rating Inventory of Executive Function (BRIEF), Neuropsychological Test Battery for Children (NEPSY) visual attention and visuomotor integration, and IQ assessment (Wechsler Preschool and Primary Scale of Intelligence Version III). Transcranial Doppler was performed using a TL2-64b 2-MHz pulsed Doppler device between 2 PM and 7 PM in all of the patients and the majority of controls while awake. Time-averaged mean of the maximal cerebral blood flow velocities was measured in the left and right middle cerebral artery and the higher used for analysis.
Results
Twenty-one snoring children had an apnea/hypopnea index <5, consistent with mild sleep-disordered breathing below the conventional threshold for surgical intervention. Compared with 17 nonsnoring controls, these children had significantly raised middle cerebral artery blood flow velocities. There was no correlation between cerebral blood flow velocities and BMI or systolic or diastolic blood pressure indices. Exploratory analyses did not reveal any significant associations with apnea/hypopnea index, apnea index, hypopnea index, mean pulse oxygen saturation, lowest pulse oxygen saturation, accumulated time at pulse oxygen saturation <90%, or respiratory arousals when examined in separate bivariate correlations or in aggregate when entered simultaneously. Similarly, there was no significant association between cerebral blood flow velocities and parental estimation of child’s exposure to sleep-disordered breathing. However, it is important to note that whereas the sleep-disordered breathing group did not exhibit significant hypoxia at the time of study, it was unclear to what extent this may have been a feature of their sleep-disordered breathing in the past. IQ measures were in the average range and comparable between groups. Measures of processing speed and visual attention were significantly lower in sleep-disordered breathing children compared with controls, although within the average range. There were similar group differences in parental-reported executive function behavior. Although there were no direct correlations, adjusting for cerebral blood flow velocities eliminated significant group differences between processing speed and visual attention and decreased the significance of differences in Behavior Rating Inventory of Executive Function scores, suggesting that cerebral hemodynamic factors contribute to the relationship between mild sleep-disordered breathing and these outcome measures.
Conclusions
Cerebral blood flow velocities measured by noninvasive transcranial Doppler provide evidence for increased cerebral blood flow and/or vascular narrowing in childhood sleep-disordered breathing; the relationship with neuropsychological deficits requires further exploration. A number of physiologic changes might alter cerebral blood flow and/or vessel diameter and, therefore, affect cerebral blood flow velocities. We were able to explore potential confounding influences of obesity and hypertension, neither of which explained our findings. Second, although cerebral blood flow velocities increase with increasing partial pressure of carbon dioxide and hypoxia, it is unlikely that the observed differences could be accounted for by arterial blood gas tensions, because all of the children in the study were healthy, with no cardiorespiratory disease, other than sleep-disordered breathing in the snoring group. Although arterial partial pressure of oxygen and partial pressure of carbon dioxide were not monitored during cerebral blood flow velocity measurement, assessment was undertaken during the afternoon/early evening when the child was awake, and all of the sleep-disordered breathing children had normal resting oxyhemoglobin saturation at the outset of their subsequent sleep studies that day. Finally, there is an inverse linear relationship between cerebral blood flow and hematocrit in adults, and it is known that iron-deficient erythropoiesis is associated with chronic infection, such as recurrent tonsillitis, a clinical feature of many of the snoring children in the study. Preoperative full blood counts were not performed routinely in these children, and, therefore, it was not possible to exclude anemia as a cause of increased cerebral blood flow velocity in the sleep-disordered breathing group. However, hemoglobin levels were obtained in 4 children, 2 of whom had borderline low levels (10.9 and 10.2 g/dL). Although there was no apparent relationship with cerebral blood flow velocity in these children (cerebral blood flow velocity values of 131 and 130 cm/second compared with 130 and 137 cm/second in the 2 children with normal hemoglobin levels), this requires verification. It is of particular interest that our data suggest a relationship among snoring, increased cerebral blood flow velocities and indices of cognition (processing speed and visual attention) and perhaps behavioral (Behavior Rating Inventory of Executive Function) function. This finding is preliminary: a causal relationship is not established, and the physiologic mechanisms underlying such a relationship are not clear. Prospective studies that quantify cumulative exposure to the physiologic consequences of sleep-disordered breathing, such as hypoxia, would be informative.
doi:10.1542/peds.2006-0092
PMCID: PMC1995426  PMID: 17015501
sleep disordered breathing; cerebral blood flow; transcranial Doppler; executive function; neuropsychological function
3.  Snoring in primary school children and domestic environment: A Perth school based study 
Respiratory Research  2004;5(1):19.
Background
The home is the predominant environment for exposure to many environmental irritants such as air pollutants and allergens. Exposure to common indoor irritants including volatile organic compounds, formaldehyde and nitrogen dioxide, may increase the risk of snoring for children. The aim of this study was to investigate domestic environmental factors associated with snoring in children.
Methods
A school-based respiratory survey was administered during March and April of 2002. Nine hundred and ninety six children from four primary schools within the Perth metropolitan area were recruited for the study. A sub-group of 88 children aged 4–6 years were further selected from this sample for domestic air pollutant assessment.
Results
The prevalences of infrequent snoring and habitual snoring in primary school children were 24.9% and 15.2% respectively. Passive smoking was found to be a significant risk factor for habitual snoring (odds ratio (OR) = 1.77; 95% confidence interval (CI): 1.20–2.61), while having pets at home appeared to be protective against habitual snoring (OR = 0.58; 95% CI: 0.37–0.92). Domestic pollutant assessments showed that the prevalence of snoring was significantly associated with exposure to nitrogen dioxide during winter. Relative to the low exposure category (<30 μg/m3), the adjusted ORs of snoring by children with medium (30 – 60 μg/m3) and high exposures (> 60 μg/m3) to NO2 were 2.5 (95% CI: 0.7–8.7) and 4.5 (95% CI: 1.4–14.3) respectively. The corresponding linear dose-response trend was also significant (P = 0.011).
Conclusion
Snoring is common in primary school children. Domestic environments may play a significant role in the increased prevalence of snoring. Exposure to nitrogen dioxide in domestic environment is associated with snoring in children.
doi:10.1186/1465-9921-5-19
PMCID: PMC535337  PMID: 15527500
4.  Effect of asthma on the risk of obstructive sleep apnea syndrome in atopic women 
Background
Obstructive sleep apnea syndrome is associated with significant morbidity and remains underdiagnosed in women. Identification of high-risk groups among women is important for early detection and treatment.
Objective
To describe the prevalence of snoring in young women with atopy and to determine the risk factors for snoring in these individuals.
Methods
The Cincinnati Childhood Allergy and Air Pollution Study is an ongoing prospective birth cohort study of infants with at least 1 atopic parent. Mothers of study participants were evaluated by questionnaire for snoring, respiratory symptoms, and smoking status. Women who snored were compared with those who did not snore. Logistic regression analysis was performed to determine risk factors for snoring.
Results
Data were available on 677 women who had at least 1 live birth. Of these 677 women, 546 (81%) were white, 122 (18%) were African American, and 9 (1%) were biracial or Asian. The mean ± SD age of the cohort at the time of evaluation for snoring was 29.6 ± 5.6 years. Of the 677 women, 231 (34%) reported snoring at least 1 night per week, and snoring almost always (5–7 nights per week) was reported by 85 (13%). An almost 2-fold risk of snoring was associated with asthma (diagnosis and current symptoms) (odds ratio, 1.8; 95% confidence interval, 1.1–2.8) and African American race (odds ratio, 1.6; 95% confidence interval, 1.04–2.6) after controlling for income level and smoking status.
Conclusions
We found a high prevalence of snoring in young women with atopy and a significant association with asthma.
PMCID: PMC2233949  PMID: 16937757
5.  Snoring during pregnancy and its relation to sleepiness and pregnancy outcome - a prospective study 
Background
The incidence of snoring and sleepiness is known to increase during pregnancy, and this might impact maternal health and obstetric outcome. However, the association between snoring and sleepiness during pregnancy is not fully understood. This study was aimed at investigating the development of snoring during pregnancy and prospectively assessing if there is an association between snoring and sleepiness or adverse pregnancy outcomes, such as preeclampsia, mode of delivery, and fetal complications.
Methods
Consecutively recruited pregnant women (n = 500) received a questionnaire concerning snoring and sleep at the 1st and 3rd trimester of pregnancy. The women who had rated their frequency of snoring at both occasions (n = 340) were divided into subgroups according to the development of snoring they reported and included in the subsequent analyses. Additional medical data were collected from the medical records.
Results
The frequency of snoring was 7.9% in the 1st trimester and increased to 21.2% in the 3rd trimester of pregnancy. The women who snored already in early pregnancy had significantly higher baseline BMI (p = 0.001) than the women who never snored, but snoring was not associated with the magnitude of weight gain during pregnancy. Snoring women were more likely to experience edema in late pregnancy than the non-snorers. Women who started to snore during pregnancy had higher Epworth Sleepiness Scores than the non snorers in both early and late pregnancy. No significant association between obstetric outcome and snoring was found.
Conclusion
Snoring does increase during pregnancy, and this increase is associated with sleepiness, higher BMI at the start of pregnancy and higher prevalence of edema, but not with weight gain.
doi:10.1186/1471-2393-14-15
PMCID: PMC3893487  PMID: 24418321
Pregnancy; Snoring; Sleepiness; Epworth sleepiness score; Body mass index; Edema; Pregnancy outcome
6.  Persistent Snoring in Preschool Children: Predictors and Behavioral and Developmental Correlates 
Pediatrics  2012;130(3):382-389.
OBJECTIVE:
To clarify whether persistent snoring in 2- to 3-year-olds is associated with behavioral and cognitive development, and to identify predictors of transient and persistent snoring.
METHODS:
Two hundred forty-nine mother/child pairs participated in a prospective birth cohort study. Based upon parental report of loud snoring ≥2 times weekly at 2 and 3 years of age, children were designated as nonsnorers, transient snorers (snored at 2 or 3 years of age, but not both), or persistent snorers (snored at both ages). We compared groups by using validated measures of behavioral and cognitive functioning. Potential predictors of snoring included child race and gender, socioeconomic status (parent education and income), birth weight, prenatal tobacco exposure (maternal serum cotinine), childhood tobacco exposure (serum cotinine), history and duration of breast milk feeding, and body mass relative to norms.
RESULTS:
In multivariable analyses, persistent snorers had significantly higher reported overall behavior problems, particularly hyperactivity, depression, and inattention. Nonsnorers had significantly stronger cognitive development than transient and persistent snorers in unadjusted analyses, but not after demographic adjustment. The strongest predictors of the presence and persistence of snoring were lower socioeconomic status and the absence or shorter duration of breast milk feeding. Secondary analyses suggested that race may modify the association of childhood tobacco smoke exposure and snoring.
CONCLUSIONS:
Persistent, loud snoring was associated with higher rates of problem behaviors. These results support routine screening and tracking of snoring, especially in children from low socioeconomic backgrounds; referral for follow-up care of persistent snoring in young children; and encouragement and facilitation of infant breastfeeding.
doi:10.1542/peds.2012-0045
PMCID: PMC3428758  PMID: 22891224
sleep-disordered breathing; behavior problems; preschool; environmental tobacco smoke; breastfeeding; overweight
7.  Markers for severity of illness associated with decreased snoring in toddlers born ELGA 
Aim
To describe the prevalence of paediatric sleep disordered breathing (SDB) symptoms in extremely low gestational age infants and identify neonatal risk factors, including early exposure to hypoxia and hyperoxia.
Methods
Patients <28 weeks gestation were monitored with high-resolution pulse oximetry. Hypoxia/hyperoxia variables were defined as percentage time of first 4 weeks of life that SaO2 < 80% or SaO2 > 98%, respectively. Parents completed part of the OSA-18 questionnaire for symptoms of SDB at 18–22 months. Logistic regression was used to test the association between risk factors and sleep symptoms.
Results
Of 182 patients recruited, 138 (76%) completed the questionnaire. The mean gestation was 26 weeks, and mean birth weight 887 grams. Loud snoring (21%) and restless sleep (24%) were the most prevalent symptoms. Female sex was associated with an increased risk of loud snoring (OR, 2.7; CI, 1.13–6.5). Prolonged mechanical ventilation, necrotizing enterocolitis and prolonged caffeine use, however, were inversely correlated with loud snoring. Neither neonatal hypoxia nor hyperoxia were associated with sleep symptoms.
Conclusions
While the prevalence of sleep disordered breathing symptoms is similar to reported rates, we found a sex difference not previously reported. Interestingly, markers for severity of illness show a pattern of being protective against loud snoring.
doi:10.1111/apa.12033
PMCID: PMC3650629  PMID: 23009601
Snoring; Sleep disordered breathing; Prematurity
8.  Prevalence of Sleep Abnormalities and Their Association with Metabolic Syndrome among Asian Indians: Chennai Urban Rural Epidemiology Study (CURES – 67) 
Objective
To estimate the prevalence of sleep abnormalities and their association with glucose intolerance and metabolic syndrome (MS) in the normal-weight urban South Indian population.
Methods
This population-based, cross-sectional study was carried out in 358 subjects aged 20–76 years randomly selected from the Chennai Urban Rural Epidemiology Study in South India. A validated questionnaire assessing various sleep abnormalities (snoring, daytime sleepiness, lack of refreshing sleep, and number of hours of sleep) was administered. All subjects underwent an oral glucose tolerance test, and anthropometric biochemical measurements were obtained to assess cardiometabolic risk factors including glucose intolerance. Diabetes risk was assessed using a previously validated Indian Diabetes Risk Score (IDRS).
Results
The overall prevalence of snoring and daytime sleepiness was 40% and 59%, respectively. Snorers were more male, older, smokers, and had higher levels of cardiometabolic risk factors. Subjects with daytime sleepiness had higher body mass index (BMI) and abdominal obesity. Both snoring (50.9% vs 30.2%, p < 0.001) and daytime sleepiness (68% vs 49.7%, p < 0.001) were more prevalent among subjects with impaired glucose metabolism compared to those with normal glucose metabolism. Both sleep measures were associated with higher diabetes risk scores, as assessed by the IDRS (snoring: trend χ2, 11.14, p = 0.001; daytime sleepiness: trend χ2, 5.12, p = 0.024). Metabolic syndrome was significantly associated with snoring even after adjusting for age, sex, family history of diabetes, physical activity, smoking, and alcohol.
Conclusion
The prevalence of snoring and daytime sleepiness is high among urban South Indians and these two sleep measures are associated with glucose intolerance, MS, and higher diabetes risk scores.
PMCID: PMC3005066  PMID: 21129351
sleep abnormalities; snoring; daytime sleepiness; cardiometabolic risk factors; metabolic syndrome; Asian Indians
9.  Excessive daytime sleepiness among rural residents in Saskatchewan 
Obstructive sleep apnea and its sequelae are emerging public health issues in North America, and symptoms are often under-recognized or under-reported. Although several patient factors have been identified, limited data regarding the prevalence of and predictors for excessive daytime sleepiness in rural or remote populations area available. Accordingly, this study used Epworth Sleepiness Scale scores to evaluate daytime sleepiness in a large rural population participating in the Saskatchewan Rural Health Study.
BACKGROUND:
Obstructive sleep apnea (OSA) is a common diagnosis in clinical practice. Excessive daytime sleepiness may be a warning for possible OSA.
OBJECTIVES:
To assess the prevalence of excessive daytime sleepiness as measured by the Epworth Sleepiness Scale (ESS) in a rural community population; potential risk factors for OSA were also assessed.
METHODS:
In 2010, a baseline respiratory health questionnaire within the Saskatchewan Rural Health Study was mailed to 11,982 households in Saskatchewan. A total of 7597 adults within the 4624 (42%) respondent households completed the ESS questionnaire. Participants were categorized according to normal or high (>10) ESS scores. Data obtained included respiratory symptoms, doctor-diagnosed sleep apnea, snoring, hypertension, smoking and demographics. Body mass index was calculated. Multivariable logistic regression analysis examined associations between high ESS scores and possible risk factors. Generalized estimating equations accounted for the two-tiered sampling procedure of the study design.
RESULTS:
The mean age of respondents was 55.0 years and 49.2% were male. The prevalence of ESS>10 and ‘doctor diagnosed’ OSA were 15.9% and 6.0%, respectively. Approximately 23% of respondents reported loud snoring and 30% had a body mass index >30 kg/m2. Of those with ‘doctor-diagnosed’ OSA, 37.7% reported ESS>10 (P<0.0001) and 47.7% reported loud snoring (P<0.0001). Risk of having an ESS>10 score increased with age, male sex, obesity, lower socioeconomic status, marriage, loud snoring and doctor-diagnosed sinus trouble.
CONCLUSIONS:
High levels of excessive daytime sleepiness in this particular rural population are common and men >55 years of age are at highest risk. Examination of reasons for residual sleepiness and snoring in persons with and without sleep apnea is warranted.
PMCID: PMC4173890  PMID: 24791255
Epworth Sleepiness Scale; Farm; Nonfarm; Obesity; Rural; Sleep apnea; Snoring; Socioeconomic
10.  Breastfeeding and Snoring: A Birth Cohort Study 
PLoS ONE  2014;9(1):e84956.
Objective
To investigate the relationship between breastfeeding and snoring in childhood.
Methods
In a cohort of children with a family history of asthma who were recruited antenatally we prospectively recorded data on infant feeding practices throughout the first year of life. Snoring status and witnessed sleep apnea were measured at age 8 years by parent-completed questionnaire. Associations were estimated by logistic regression with, and without, adjustment for sets of confounders designed to exclude biasing effects.
Results
Habitual snoring was reported in 18.8% of the sample, and witnessed apnea in 2.7%. Any breastfeeding for longer than one month was associated with a reduced risk of habitual snoring at age 8 (adjusted OR 0.48, 95% CI 0.29 to 0.81) and duration of breastfeeding was inversely associated with the prevalence of habitual snoring (adjusted OR 0.79, 95% CI 0.62 to 1.00). Any breastfeeding for longer than 1 month was associated with a lower risk of witnessed sleep apnea (adjusted OR 0.17, 95% CI 0.04 to 0.71). The protective associations were not mediated by BMI, current asthma, atopy or rhinitis at age 8 years.
Conclusions
Breastfeeding for longer than one month decreases the risk of habitual snoring and witnessed apneas in this cohort of children with a family history of asthma. The underlying mechanism remains unclear but the finding would be consistent with a beneficial effect of the breast in the mouth on oropharyngeal development with consequent protection against upper airway dysfunction causing sleep-disordered breathing.
doi:10.1371/journal.pone.0084956
PMCID: PMC3885662  PMID: 24416321
11.  Comparative Effects of Snoring Sound between Two Minimally Invasive Surgeries in the Treatment of Snoring: A Randomized Controlled Trial 
PLoS ONE  2014;9(5):e97186.
Background
Minimally invasive surgeries of the soft palate have emerged as a less-invasive treatment for habitual snoring. To date, there is only limited information available comparing the effects of snoring sound between different minimally invasive surgeries in the treatment of habitual snoring.
Objective
To compare the efficacy of palatal implant and radiofrequency surgery, in the reduction of snoring through subjective evaluation of snoring and objective snoring sound analysis.
Patients and Method
Thirty patients with habitual snoring due to palatal obstruction (apnea-hypopnea index ≤15, body max index ≤30) were prospectively enrolled and randomized to undergo a single session of palatal implant or temperature-controlled radiofrequency surgery of the soft palate under local anesthesia. Snoring was primarily evaluated by the patient with a 10 cm visual analogue scale (VAS) at baseline and at a 3-month follow-up visit and the change in VAS was the primary outcome. Moreover, life qualities, measured by snore outcomes survey, and full-night snoring sounds, analyzed by a sound analytic program (Snore Map), were also investigated at the same time.
Results
Twenty-eight patients completed the study; 14 received palatal implant surgery and 14 underwent radiofrequency surgery. The VAS and snore outcomes survey scores were significantly improved in both groups. However, the good response (postoperative VAS ≤3 or postoperative VAS ≤5 plus snore outcomes survey score ≥60) rate of the palatal implant group was significantly higher than that of the radiofrequency group (79% vs. 29%, P = 0.021). The maximal loudness of low-frequency (40–300 Hz) snores was reduced significantly in the palatal implant group. In addition, the snoring index was significantly reduced in the radiofrequency group.
Conclusions
Both palatal implants and a single-stage radiofrequency surgery improve subjective snoring outcomes, but palatal implants have a greater effect on most measures of subjective and objective snoring. Multi-stage radiofrequency surgery was not tested.
Trial Registration
ClinicalTrials.gov NCT01955083
doi:10.1371/journal.pone.0097186
PMCID: PMC4016275  PMID: 24816691
12.  Natural history of snoring and related behaviour problems between the ages of 4 and 7 years. 
In 1989-90 a survey was carried out of the prevalence of snoring and related symptoms in 782 4 to 5 year old children. Two years later, in 1992, the same group of children was studied to gather information on the natural history of snoring and the related behaviour problems. A total of 507/782 (64.8%) completed questionnaires were received. Comparison of the responses with the 1989-90 survey showed that those who did not reply to the questionnaire were no different from the respondents in terms of the prevalence of snoring, daytime sleepiness, hyperactivity, and restless sleep. The overall prevalence of habitual snoring did not change between the two surveys (12.1% in 1989-90 v 11.4% in 1992), though more than half of the children who snored habitually in the original survey no longer did so. There was little change in the prevalence of hyperactivity (24.2% in 1989-90 v 20.7% in 1992) or restless sleep (both 39%) among the 507 who responded to the present survey. The prevalence of daytime sleepiness, however, did decrease substantially (20.7% in 1989-90 v 10.2% in 1992). There was moderate agreement between the individual questionnaire responses for the 1989-90 and 1992 surveys for snoring (weighted kappa 0.52), but poor agreement for the other symptoms (daytime sleepiness 0.37, hyperactivity 0.35, and restless sleep 0.38). Trend analysis showed that the increasing prevalence of sleepiness, hyperactivity, and restless sleep across the snoring categories was highly significant. Daytime sleepiness, hyperactivity, and restless sleep were all significantly more common in the habitual snorers than in those who never snored. Relative risks (95% confidence interval) were as follows: daytime sleepiness 6.13 (2.5 to 14.9), hyperactivity 2.78 (1.6 to 4.7), and restless sleep 2.3 (1.6 to 3.2). Though habitual snoring and the associated behaviour problems resolved spontaneously over two years in about half of the children with these symptoms, there is still the same overall percentage with these problems due to the emergence of new cases.
PMCID: PMC1029917  PMID: 8067797
13.  Loud snoring is a risk factor for occupational injury in farmers 
BACKGROUND:
Loud snoring is a common symptom in the general population. The evidence-based literature indicates that snoring may be associated with sleep fragmentation and sleep apnea, which may affect cognitive function and predispose to occupational injury. High rates of occupational injury occur on farms and may be related to personal and health factors. Thus, loud snoring may not be a trivial symptom and should be considered as important in medical assessments.
METHODS:
A prospective cohort study was conducted in Saskatchewan. Baseline questionnaires were completed for 5502 individuals by representatives from 2390 farms. Sleep patterns at baseline were categorized as the following: no reported sleep disorders; physician-diagnosed sleep apnea (treatment unknown); and loud snoring. Survival analyses were used to relate sleep patterns with subsequent injury.
RESULTS:
A total of 6.7% (369 of 5502) of participants reported a possible sleep disorder. Of these, 69.4% (256 of 369) reported loud snoring only. Loud snoring was only associated with a consistent increase in risk (eg, HR 1.45 [95 CI 1.07 to 1.99 for work-related injury]) for five farm injury outcomes. Relationships between physician-diagnosed sleep apnea and time to first injury were not significant, presumably because a diagnosis of sleep apnea implied treatment for sleep apnea.
DISCUSSION:
Sleep disorders are an important potential risk factor for occupational injury on farms. Substantial proportions of farm residents report loud snoring and this is related to subsequent injury. Some of these cases may represent sleep fragmentation or undiagnosed obstructive sleep apnea. Identification and clinical management of sleep disorders related to snoring should be part of health assessments conducted by physicians.
PMCID: PMC3628646  PMID: 23457674
Agriculture; Farming; Injury; Occupational health; Sleep disorders; Snoring
14.  Atopy as a Risk Factor for Habitual Snoring at Age 1 Year 
Chest  2006;129(4):942-946.
Study objectives
To determine the prevalence of habitual snoring (HS) in 1-year-old children, and to assess the relationship between HS and atopic status in these children.
Design
Cross-sectional evaluation of a birth cohort selected from the population.
Setting
Ohio and Kentucky River Valley communities.
Participants
Children participating in the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) were recruited for this study.
Measurements and results
At age 1 year, the children were evaluated for atopic status and exposure to environmental tobacco smoke (ETS). Parents were asked to complete a questionnaire pertaining to their snoring frequency and that of their child. Children with HS (snoring three or more times per week) were compared to those who either did not snore or snored less than three times per week. Data were available on 681 of the 700 children participating in CCAAPS study. Of these 681 children (377 boys and 304 girls), 542 were white (80%), 118 were African American (17%), and 21 were biracial or Asian (3%). The mean age (± SD) of our cohort at the time of assessment for snoring was 13.7 ± 2.6 months. Of the 681 children, 105 snored habitually (15%). There was a significant association between HS and the following: (1) positive atopic status (p = 0.005); (2) African-American race (p < 0.01); and (3) a history of snoring in the father (p < 0.01) or in the mother (p < 0.01). There was, however, no association between HS and ETS.
Conclusions
We found a 15% prevalence of HS in 1-year-old children born to atopic parents and a significant association with positive atopic status.
doi:10.1378/chest.129.4.942
PMCID: PMC2233942  PMID: 16608942
allergic rhinitis; children; environmental tobacco smoke; skin-prick test; obstructive sleep-disordered breathing
15.  Snoring and Glaucoma 
PLoS ONE  2014;9(2):e88949.
Purpose
To examine a potential association between snoring and glaucoma in a population-based setting.
Methods
The population-based Beijing Eye Study 2011 included 3468 subjects with an age of 50+ years. The participants underwent a detailed ophthalmic examination. Glaucoma was determined according to the ophthalmoscopic appearance of the optic nerve head. Snoring assessed in an interview was graded into “severe snoring”, “moderate snoring”, and “no snoring”.
Results
Data on snoring and glaucoma were available for 3146 subjects. Snoring was reported for 1787 (66.8%) subjects, with moderate snoring reported for 1384 (44.0%) subjects and severe snoring for 403 (12.8%) subjects. In multivariate analysis, prevalence of severe snoring was significantly associated with male gender (P = 0.002; regression coefficient B: 0.36; Odds ratio (OR): 1.44 (95% confidence interval (CI): 1.14, 1.81)), higher body mass index (P<0.001; B: 0.12; OR: 1.13 (95%CI: 1.09, 1.16)), higher systolic blood pressure (P<0.001; B: 0.01; OR: 1.01 (95%CI: 1.005, 1.02)), younger age (P = 0.007; B: −0.018; OR: 0.98 (95%CI: 0.97, 0.995)), and higher cognitive function (P = 0.03; B: 0.04; OR: 1.04 (95%CI: 1.004, 1.08)), however it was not significantly associated with the prevalence of open-angle glaucoma (P = 0.10; B: −0.63; OR: 0.53 (95%CI: 0.25, 1.12)). Prevalence of severe snoring was neither significantly associated with the prevalence of angle-closure glaucoma (P = 0.65), retinal vein occlusions (P = 0.24), neuroretinal rim area (P = 0.19), retinal nerve fiber layer thickness (P = 0.16) nor vertical cup/disc ratio (P = 0.64).
Conclusions
Severe snoring was not significantly associated with the prevalence of open-angle glaucoma, angle-closure glaucoma or retinal vein occlusions after adjustment for age, gender, body mass index, systolic blood pressure and cognitive function score. Our population-based study did not reveal that snoring was a risk factor for glaucoma and thus did not provide a reason to assess or to treat snoring in patients with glaucoma.
doi:10.1371/journal.pone.0088949
PMCID: PMC3923859  PMID: 24551196
16.  Prevalence and risk factors for active convulsive epilepsy in rural northeast South Africa 
Epilepsy Research  2014;108(4):782-791.
Highlights
•Epilepsy is prevalent in rural South Africa, but less than other parts of Africa.•Most epilepsy starts in childhood.•Poor obstetric history and snoring were associated with active convulsive epilepsy.•HIV and parasitic infection were not associated with active convulsive epilepsy.
Summary
Rationale
Epilepsy is among the most common neurological disorders worldwide. However, there are few large, population-based studies of the prevalence and risk factors for epilepsy in southern Africa.
Methods
From August 2008 to February 2009, as part of a multi-site study, we undertook a three-stage, population-based study, embedded within the Agincourt health and socio-demographic surveillance system, to estimate the prevalence and identify risk factors of active convulsive epilepsy (ACE) in a rural South African population.
Results
The crude prevalence of ACE, after adjusting for non-response and the sensitivity of the screening method, was 7.0/1,000 individuals (95%CI 6.4–7.6) with significant geographic heterogeneity across the study area. Being male (OR = 2.3; 95%CI 1.6–3.2), family history of seizures (OR = 4.0; 95%CI 2.0–8.1), a sibling with seizures (OR = 7.0; 95%CI 1.6–31.7), problems after delivery (OR = 5.9; 95%CI 1.2–24.6), and history of snoring (OR = 6.5; 95%CI 4.5–9.5) were significantly associated with ACE. For children, their mother's exposure to some formal schooling was protective (OR = 0.30; 95%CI 0.11–0.84) after controlling for age and sex. Human immunodeficiency virus was not found to be associated with ACE.
Conclusions
ACE is less frequent in this part of rural South Africa than other parts of sub-Saharan Africa. Improving obstetric services could prevent epilepsy. The relationship between snoring and ACE requires further investigation, as does the relative contribution of genetic and environmental factors to examine the increased risk in those with a family history of epilepsy.
doi:10.1016/j.eplepsyres.2014.01.004
PMCID: PMC4000269  PMID: 24582322
Epilepsy; Prevalence; Case-control; Risk factors; Population-based
17.  Glucose intolerance and gestational diabetes risk in relation to sleep duration and snoring during pregnancy: a pilot study 
BMC Women's Health  2010;10:17.
Background
Insufficient sleep and poor sleep quality, considered endemic in modern society, are associated with obesity, impaired glucose tolerance and diabetes. Little, however, is known about the consequences of insufficient sleep and poor sleep quality during pregnancy on glucose tolerance and gestational diabetes.
Methods
A cohort of 1,290 women was interviewed during early pregnancy. We collected information about sleep duration and snoring during early pregnancy. Results from screening and diagnostic testing for gestational diabetes mellitus (GDM) were abstracted from medical records. Generalized linear models were fitted to derive relative risk (RR) and 95% confidence intervals (95% CIs) of GDM associated with sleep duration and snoring, respectively.
Results
After adjusting for maternal age and race/ethnicity, GDM risk was increased among women sleeping ≤ 4 hours compared with those sleeping 9 hours per night (RR = 5.56; 95% CI 1.31-23.69). The corresponding RR for lean women (<25 kg/m2) was 3.23 (95% CI 0.34-30.41) and 9.83 (95% CI 1.12-86.32) for overweight women (≥ 25 kg/m2). Overall, snoring was associated with a 1.86-fold increased risk of GDM (RR = 1.86; 95% CI 0.88-3.94). The risk of GDM was particularly elevated among overweight women who snored. Compared with lean women who did not snore, those who were overweight and snored had a 6.9-fold increased risk of GDM (95% CI 2.87-16.6).
Conclusions
These preliminary findings suggest associations of short sleep duration and snoring with glucose intolerance and GDM. Though consistent with studies of men and non-pregnant women, larger studies that include objective measures of sleep duration, quality and apnea are needed to obtain more precise estimates of observed associations.
doi:10.1186/1472-6874-10-17
PMCID: PMC2885310  PMID: 20470416
18.  Snoring as a risk factor for disease: an epidemiological survey. 
In a study conducted in four family practice units in Toronto, Canada, 2001 subjects reported on snoring and medical conditions in members of their households. For spouses the prevalence of snoring increased with age up to the seventh decade, with a higher prevalence of nearly 85% in husbands. For 11 medical problems an association existed between snoring, its frequency, and the presence of the condition. This association continued when the data were corrected for sex, age, and marital state. For hypertension both men and women who snored between the fifth and 10th decades had a twofold increase over non-snorers. The prevalence of heart disease and other conditions, except for diabetes and asthma, also increased in snorers in this age group. When corrected for smoking and obesity the association between snoring, hypertension, and heart disease persisted. These findings extend those of Lugaresi et al, and if they could be confirmed snoring as a risk factor for conditions other than sleep apnoea and sleep disorders might be considered. Methods of alleviating the acoustic annoyance of snoring may also provide direct medical benefits.
PMCID: PMC1417471  PMID: 3928056
19.  Clinical Screening of School Children for Polysomnography to Detect Sleep-Disordered Breathing—the Tucson Children’s Assessment of Sleep Apnea Study (TuCASA) 
Study Objectives
This report describes the associations, specificities, sensitivities, and positive likelihood ratios of clinical symptoms to a finding of sleep-disordered breathing (SDB) on polysomnography in children.
Methods
Four hundred eighty unattended home polysomnograms were completed in a community-based cohort of children 6 to 11 years of age (50% boys, 42.3% Hispanic, and 52.9% between the ages of 6 and 8 years). SDB was present if the child had a respiratory disturbance index of ≥ 1 event per hour.
Measurements and Results
Boys were twice as likely as girls to have SDB (p<.01); however, witnessed apnea, ethnicity, age, obesity, and air-way size (based on clinical evaluation) were not significantly different between those with SDB and without SDB. The sensitivity of any individual or combined clinical symptoms was poor, with male sex (60%) and snoring (29.5%) having the greatest proportion of SDB children. However, high specificities for snoring (89.5%), excessive daytime sleepiness (86.3%), and learning problems (95.9%) were noted. Combinations of symptoms such as snoring+male sex (95.1%), snoring+excessive daytime sleepiness (97.0%), and snoring+learning problems (98.9%) had specificities approaching 1. Positive likelihood ratios for snoring (2.8), learning (2.8), and symptoms combined with snoring such as snoring+male sex(3.9), snoring+learning problems (4.0), and snoring+excessive daytime sleepiness (2.9) were observed.
Conclusions
Snoring, excessive daytime sleepiness, and learning problems are each highly specific, but not sensitive, for SDB in 6- to 11-year old children. However, specificities and positive likelihood ratios for the combination of some of these symptoms is sufficiently high to suggest that some children may not require a polysomnogram for the diagnosis of SDB.
PMCID: PMC1307497  PMID: 16429591
Sleep; children; sleep-disordered breathing; sleep apnea; respiratory disturbance index
20.  Snoring and risk for obstructive sleep apnea among nigerians with heart failure: Prevalence and clinical correlates 
Background:
Heart failure is an important cause of morbidity and mortality in developing nations like Nigeria. Sleep apnea and snoring has recently been recognized to be a cardiovascular risk factor. Sleep apnea is yet to be well studied among Africans with heart failure. We aimed to determine the prevalence of snoring and high risk for obstructive sleep apnea among Nigerians with stable heart failure.
Materials and Methods:
We studied 103 subjects that included 62 patients with heart failure and 41 control subjects. Demographic parameters and clinical examination were performed on the participants. The Berlin score and the Epworth Sleepiness Scale were administered for each participant. Echocardiography was done on all participants. Statistical analysis was done using Statistical Package for Social Sciences (SPSS) 17.0.
Results:
Snoring was reported in 48.4% of subjects with heart failure compared to 22.0% of control subjects ( P < 0.005). High risk for obstructive sleep apnea using the Berlin score was documented in 51.6% of heart failure subjects compared to 7.31% of controls. Excessive daytime somnolence occurred more in heart failure patients (51.6% vs. 9.8%, P < 0.05). Snorers tended to be older and were more likely to be obese than nonsnorers. Systolic blood pressure and fasting blood sugar were significantly higher among heart failure subjects with snoring than those without snoring (131.9 ± 19.2 vs. 119.2 ± 15.7 and 6.0 ± 0.8 vs. 5.4 ± 2.7, P < 0.005).
Conclusion:
Heart failure seems to be associated with snoring and a high risk for obstructive sleep apnea among Africans with heart failure. Assessment for sleep disordered breathing should be incorporated into their routine clinical workup.
doi:10.4103/1995-705X.107115
PMCID: PMC3621219  PMID: 23580920
Clinical correlates; heart failure; Nigeria; prevalence; sleep apnea; snoring
21.  Snoring and Insomnia are Not Associated with Subclinical Atherosclerosis in the Northern Manhattan Study (NOMAS) 
Background and Aims
Sleep disordered breathing (SDB) is a risk factor for stroke, but its association with subclinical atherosclerosis remains controversial. Snoring and insomnia are frequently co-morbid with SDB and may contribute to stroke. Data on the relationship between snoring and insomnia with atherosclerotic disease is sparse. We investigated the relationship between insomnia, snoring and carotid intima-media thickness (IMT), a marker of subclinical atherosclerosis, in the Northern Manhattan Study (NOMAS).
Methods
A group of 1,605 participants (mean age 65 ± 8 years; 40% men; 61% Hispanic, 19% black, 20% white) who had carotid IMT measurements performed was assessed for self-reported sleep habits. Habitual snoring was defined as self-reported snoring > 4 times per week. Presence of insomnia was based on three items extracted from the Hamilton Rating Scale for Depression. Carotid IMT was expressed as a mean composite measure of IMT in the carotid bifurcation, common and internal carotid artery. Multivariate linear regression models were used to identify associations between snoring, insomnia and carotid IMT.
Results
Habitual snoring was present in 29% of the subjects and insomnia in 26%. There was a higher prevalence of self reported snoring (84%) and insomnia (66%) among Hispanics than non-Hispanics. The mean total carotid IMT was 0.95 ± 0.09 mm; among those with self reported snoring was 0.94 ± 0.09 mm; and among those with insomnia was 0.95 ± 0.08 mm. After controlling for age, sex, race-ethnicity, BMI and cardiovascular risk factors, snoring (p= 0.986) and insomnia (p= 0.829) were not significantly associated with increased carotid IMT.
Conclusion
Snoring and insomnia were not significantly associated with subclinical atherosclerosis in this population based community cohort.
doi:10.1111/j.1747-4949.2010.00438.x
PMCID: PMC2907549  PMID: 20636708
sleep; snoring; insomnia; African American; Hispanic; Intima-Media Thickness; Risk factors; Sonography; Ultrasound
22.  Habitual snoring and depressive symptoms during pregnancy 
Background
Depression is frequently observed in patients with untreated sleep-disordered breathing (SDB) in the general population. Pregnant women are particularly vulnerable since pregnancy increases the risk of both SDB and depressive symptoms. However, no study has investigated whether SDB symptoms prior to or in early pregnancy are associated with such mood problems.
Methods
A retrospective chart review of pregnant women. Women were included if they attended prenatal clinics between June 2007 and July 2010, were ≥18 years old, pregnant with a single fetus, and had been screened for habitual snoring as well as depressive symptoms using the Edinburgh Postnatal Depression Scales (EPDS).
Results
In total, 362 women were included and 32.3% reported habitual snoring. Twenty-nine percent of women had an EPDS score ≥10. Significantly more snoring women, compared to non-snorers, had an EPDS score ≥10 (42.7% vs. 22.9%, p < 0.001) despite the mean EPDS values not reaching statistical significance (6.1 ± 4.9 vs. 5.4 ± 5.0, p = 0.2). In a logistic regression model controlling for parity, the presence of pre-pregnancy obesity, presence of a partner, sleep quality, African American race, maternal educational level, pre-eclampsia, and diabetes, snoring was independently associated with a prenatal EPDS score ≥10 (O.R. 2.0, 95%CI 1.13-3.46; p = 0.023).
Conclusion
Maternal snoring may be a risk factor for prenatal depressive symptoms. Further investigation of the temporal relationship between maternal snoring and depressive symptoms is warranted.
doi:10.1186/1471-2393-13-113
PMCID: PMC3660222  PMID: 23679132
Pregnancy; Snoring; Sleep quality; Depressive symptoms; EPDS
23.  Insomnia symptoms in older adults: associated factors and gender differences 
Objectives
The aim of this study was to examine the factors associated with insomnia in community-dwelling elderly as a function of the nature and number of insomnia symptoms (IS) e.g. difficulty with initiating sleep (DIS), difficulty with maintaining sleep (DMS) and early morning awakening (EMA).
Methods
IS were assessed in a sample of 2673 men and 3213 women aged 65 years and over. The participants were administered standardized questionnaires regarding the frequency of IS and other sleep characteristics (snoring, nightmares, sleeping medication, sleepiness) as well as various socio-demographic, behavioral and clinical variables, and measures of physical and mental health.
Results
More than 70% of men and women reported at least one IS, DMS being the most prevalent symptom in both men and women. Women reported more frequently two or three IS whereas men reported more often only one IS. Multivariate regression analyses stratified by gender showed that men and women shared numerous factors associated with IS, sleeping medication, nightmares, sleepiness, chronic diseases, and depression being independently associated with two or three IS. For both sexes, age was associated with only one IS in all age categories. Loud snoring was strongly associated with increased DMS in men only. High body mass index increased the risk for DIS in men but tended to decrease it in women. In women, hormonal replacement therapy, Mediterranean diet, caffeine and alcohol intake had a protective effect.
Conclusion
Our data suggest that women may have specific predisposition factors of multiple IS which may involve both behavioral and hormonal factors. Identification and treatment of these risk factors may form the basis of an intervention program for reduction of insomnia symptoms in the elderly..
doi:10.1097/JGP.0b013e3181e049b6
PMCID: PMC3179987  PMID: 20808113
Age Factors; Aged; Aged, 80 and over; Female; France; epidemiology; Humans; Male; Prevalence; Risk Factors; Self Report; Sex Characteristics; Sex Factors; Sleep Initiation and Maintenance Disorders; diagnosis; epidemiology
24.  Energy Types of Snoring Sounds in Patients with Obstructive Sleep Apnea Syndrome: A Preliminary Observation 
PLoS ONE  2012;7(12):e53481.
Background
Annoying snore is the principle symptom and problem in obstructive sleep apnea syndrome (OSAS). However, investigation has been hampered by the complex snoring sound analyses.
Objective
This study was aimed to investigate the energy types of the full-night snoring sounds in patients with OSAS.
Patients and Method
Twenty male OSAS patients underwent snoring sound recording throughout 6 hours of in-lab overnight polysomnogragphy. Snoring sounds were processed and analyzed by a new sound analytic program, named as Snore Map®. We transformed the 6-hour snoring sound power spectra into the energy spectrum and classified it as snore map type 1 (monosyllabic low-frequency snore), type 2 (duplex low-&mid-frequency snore), type 3 (duplex low- & high-frequency snore), and type 4 (triplex low-, mid-, & high-frequency snore). The interrator and test-retest reliabilities of snore map typing were assessed. The snore map types and their associations among demographic data, subjective snoring questionnaires, and polysomnographic parameters were explored.
Results
The interrator reliability of snore map typing were almost perfect (κ = 0.87) and the test-retest reliability was high (r = 0.71). The snore map type was proportional to the body mass index (r = 0.63, P = 0.003) and neck circumference (r = 0.52, P = 0.018). Snore map types were unrelated to subjective snoring questionnaire scores (All P>0.05). After adjustment for body mass index and neck circumference, snore map type 3–4 was significantly associated with severity of OSAS (r = 0.52, P = 0.026).
Conclusions
Snore map typing of a full-night energy spectrum is feasible and reliable. The presence of a higher snore map type is a warning sign of severe OSAS and indicated priority OSAS management. Future studies are warranted to evaluate whether snore map type can be used to discriminate OSAS from primary snoring and whether it is affected by OSAS management.
doi:10.1371/journal.pone.0053481
PMCID: PMC3534069  PMID: 23300931
25.  Prevalence of Recurrent Otitis Media in Habitually Snoring School-Aged Children 
Sleep medicine  2007;9(5):549-554.
Introduction
The pathophysiology of obstructive sleep apnea (OSA) and recurrent otitis media (ROM) is intimately associated with the presence of adenotonsillar hypertrophy in children. However, it remains unclear whether habitually snoring children have a higher prevalence of ROM and whether they require tympanostomy tube placement more frequently.
Methods
Questionnaires collected from parental surveys of 5–7–year-old children attending the public schools in Louisville, KY were retrospectively reviewed for the presence of habitual snoring (HS), ROM, and the need for tympanostomy tube insertion.
Results
There were 16,321 surveys with complete datasets (51.2% boys; 18.6% African American (AA) with a mean age of 6.2±0.7 years). Of these children, 1,844 (11.3 %) were HS (53% boys; 25.9% AA); and, of these, 827 HS had also a positive history of ROM (44.8%) with a slight predominance in males (55%). In addition, 636 of these children underwent placement of tympanostomy tubes (i.e., 34.4% of all HS and 76.9% of ROM). Among the 14,477 non-snoring children (NS), ROM was reported in 4,247 NS children (29.3%; p<0.000001; odds ratio [OR]: 1.95; confidence interval [CI]: 1.77–2.16) of which 57.6% were boys, and 1,969 NS with ROM underwent tympanostomy tube placement (i.e., 46.3% of those with ROM and 13.6% of all non-snoring children). Thus, the risk for tympanostomy tube placement was also greater among HS compared to NS children (p<0.00001; OR: 2.19; CI: 1.98–2.43).
Conclusions
Habitual snoring is associated with a significant increase in the prevalence of recurrent otitis media and the need for tympanostomy tube placement. Further studies aiming to assess the prevalence of obstructive sleep apnea among children with ROM are needed.
doi:10.1016/j.sleep.2007.08.002
PMCID: PMC2527176  PMID: 17921061

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