Poor Sleep in Patients with Multiple Sclerosis

Background

Poor sleep is a frequent symptom in patients with multiple sclerosis (MS). Sleep may be influenced by MS-related symptoms and adverse effects from immunotherapy and symptomatic medications. We aimed to study the prevalence of poor sleep and the influence of socio-demographic and clinical factors on sleep quality in MS- patients.

Methods

A total of 90 MS patients and 108 sex-and age- matched controls were included in a questionnaire survey. Sleep complaints were evaluated by Pittsburgh Sleep Quality Index (PSQI) and a global PSQI score was used to separate good sleepers (≤5) from poor sleepers (>5). Excessive daytime sleepiness, the use of immunotherapy and antidepressant drugs, symptoms of pain, depression, fatigue and MS-specific health related quality of life were registered. Results were compared between patients and controls and between good and poor sleepers among MS patients.

Results

MS patients reported a higher mean global PSQI score than controls (8.6 vs. 6.3, p = 0.001), and 67.1% of the MS patients compared to 43.9% of the controls (p = 0.002) were poor sleepers. Pain (p = 0.02), fatigue (p = 0.001), depression (p = 0.01) and female gender (p = 0.04) were associated with sleep disturbance. Multivariate analyses showed that female gender (p = 0.02), use of immunotherapy (p = 005) and a high psychological burden of MS (p = 0.001) were associated with poor sleep among MS patients.

Conclusions

Poor sleep is common in patients with MS. Early identification and treatment of modifiable risk factors may improve sleep and quality of life in MS.     

Diseases in Patients Coming to a Sleep Center with Symptoms Related to Restless Legs Syndrome

Study Objective

To explore the profile of patients who visit a sleep center with symptoms that fulfill the four essential criteria for restless legs syndrome (RLS).

Design

A prospective study.

Setting

Outpatients from one sleep disorders clinic in Taiwan.

Participants

1,200 consecutive patients visit sleep disorders clinic with any sleep complaints.

Interventions

After completing a history and physical examination, all participants answered the RLS questionnaire. Subjects who fulfilled the four essential criteria for RLS were referred to a special clinic. A work-up including blood tests, polysomnography, and specialized neurological tests etc. was performed to make the final diagnosis.

Measurements and Results

A total of 1,185 participants were enrolled, and, of these, 131(11.1%) fulfilled the four essential criteria for RLS, and 121 completed the supplemental work-up. Their mean age was 47.6±13.3 and 52.9% were male. Insomnia and snoring were the most common chief complaints. Obstructive sleep apnea syndrome and other diseases were found in 103 patients. Only 18 (14.9%) patients had no comorbid condition and were diagnosed with primary RLS.

Conclusions

Symptoms of RLS are common in patients with sleep complaints. Even in a sleep clinic, using a questionnaire approach for identification of RLS has a low positive predictive value. Clinicians should pay attention to the limitations of the 4-item questionnaire in diagnosis of RLS and also the importance of a careful differential diagnosis to identify possible secondary causes of RLS.     

Sleep Disorders in Parkinson’s Disease: Clinical Features,Iron Metabolism and Related Mechanism

Objective

To investigate clinical features, iron metabolism and neuroinflammation in Parkinson’s disease (PD) patients with sleep disorders (SD).

Methods

211 PD patients were evaluated by Pittsburgh Sleep Quality Index (PSQI) and a body of scales for motor symptoms and non-motor symptoms. 94 blood and 38 cerebral spinal fluid (CSF) samples were collected and iron and its metabolism-relating proteins, neuroinflammatory factors were detected and analyzed.

Results

136 cases (64.5%) of PD patients were accompanied by SD. Factor with the highest score in PSQI was daytime dysfunction. Depression, restless leg syndrome, autonomic symptoms and fatigue contributed 68.6% of the variance of PSQI score. Transferrin level in serum and tumor necrosis factor–α level in CSF decreased, and the levels of iron, transferrin, lactoferrin and prostaglandin E₂ in CSF increased in PD patients with SD compared with those without SD. In CSF, prostaglandin E₂ level was positively correlated with the levels of transferrin and lactoferrin, and tumor necrosis factor–α level was negatively correlated with the levels of iron, transferrin and lactoferrin in CSF.

Conclusions

Depression, restless leg syndrome, autonomic disorders and fatigue are the important contributors for the poor sleep in PD patients. Abnormal iron metabolism may cause excessive iron deposition in brain and be related to SD in PD patients through dual potential mechanisms, including neuroinflammation by activating microglia and neurotoxicity by targeting neurons. Hence, inhibition of iron deposition-related neuroinflammation and neurotoxicity may cast a new light for drug development for SD in PD patients.     

Construct Validity and Factor Structure of the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale in a Multi-National Study of African,South East Asian and South American College Students

Background

The Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) are questionnaires used to assess sleep quality and excessive daytime sleepiness in clinical and population-based studies. The present study aimed to evaluate the construct validity and factor structure of the PSQI and ESS questionnaires among young adults in four countries (Chile, Ethiopia, Peru and Thailand).

Methods

A cross-sectional study was conducted among 8,481 undergraduate students. Students were invited to complete a self-administered questionnaire that collected information about lifestyle, demographic, and sleep characteristics. In each country, the construct validity and factorial structures of PSQI and ESS questionnaires were tested through exploratory and confirmatory factor analyses (EFA and CFA).

Results

The largest component-total correlation coefficient for sleep quality as assessed using PSQI was noted in Chile (r = 0.71) while the smallest component-total correlation coefficient was noted for sleep medication use in Peru (r = 0.28). The largest component-total correlation coefficient for excessive daytime sleepiness as assessed using ESS was found for item 1 (sitting/reading) in Chile (r = 0.65) while the lowest item-total correlation was observed for item 6 (sitting and talking to someone) in Thailand (r = 0.35). Using both EFA and CFA a two-factor model was found for PSQI questionnaire in Chile, Ethiopia and Thailand while a three-factor model was found for Peru. For the ESS questionnaire, we noted two factors for all four countries

Conclusion

Overall, we documented cross-cultural comparability of sleep quality and excessive daytime sleepiness measures using the PSQI and ESS questionnaires among Asian, South American and African young adults. Although both the PSQI and ESS were originally developed as single-factor questionnaires, the results of our EFA and CFA revealed the multi- dimensionality of the scales suggesting limited usefulness of the global PSQI and ESS scores to assess sleep quality and excessive daytime sleepiness.     

Optimal Sleep Duration in the Subarctic with Respect to Obesity Risk Is 8–9 Hours

Introduction

Sleep duration, chronotype and social jetlag have been associated with body mass index (BMI) and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7–8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables. The aims of our study were to examine the associations between sleep variables and body composition for people living in the subarctic, taking a range of variables into consideration, including lifestyle variables, health variables and biological factors.

Methods

The cross sectional population Tromsø Study was conducted in northern Norway, above the Arctic Circle. 6413 persons aged 30–65 years completed questionnaires including self-reported sleep times, lifestyle and health. They also measured height, weight, waist and hip circumference, and biological factors (non-fasting serum level of cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and glucose). The study period was from 1 October 2007 to 19 December 2008.

Results

The optimal sleep length regarding BMI and waist circumference was found to be 8–9 hours. Short sleepers (<6 h) had about 80% increased risk of being in the BMI≥25 kg/m2 group and male short sleepers had doubled risk of having waist circumference ≥102 cm compared to 8–9 hours sleepers. We found no impact of chronotype or social jetlag on BMI or abdominal obesity after controlling for health, lifestyle, and biological parameters.

Conclusions

In our subarctic population, the optimal sleep duration time regarding risk of overweight and abdominal obesity was 8–9 hours, which is one hour longer compared to findings from other studies. Short sleepers had 80% increased risk of being overweight, and men had a doubled risk of having abdominal obesity. We found no associations between chronotype or social jetlag and BMI or abdominal obesity, when we took a range of life-style, health and biological variables into consideration.     

Relative Metabolic Stability,but Disrupted Circadian Cortisol Secretion during the Fasting Month of Ramadan

Background

Chronic feeding and sleep schedule disturbances are stressors that exert damaging effects on the organism. Practicing Muslims in Saudi Arabia go through strict Ramadan fasting from dawn till sunset for one month yearly. Modern era Ramadan practices in Saudi Arabia are associated with disturbed feeding and sleep patterns, namely abstaining from food and water and increasing daytime sleep, and staying awake and receiving food and water till dawn.

Hypothesis

Strict Ramadan practices in Saudi Arabia may influence metabolism, sleep and circadian cortisol secretion.

Protocol

Young, male Ramadan practitioners were evaluated before and two weeks into the Ramadan. Blood samples were collected at 9.00 am and 9.00 pm for measurements of metabolic parameters and cortisol. Saliva was collected serially during the day for cortisol determinations.

Results

Ramadan practitioners had relative metabolic stability or changes expected by the pattern of feeding. However, the cortisol circadian rhythm was abolished and circulating insulin levels and HOMA index were increased during this period.

Discussion

The flattening of the cortisol rhythm is typical of conditions associated with chronic stress or endogenous hypercortisolism and associated with insulin resistance.

Conclusions

Modern Ramadan practices in Saudi Arabia are associated with evening hypercortisolism and increased insulin resistance. These changes might contribute to the high prevalence of chronic stress-related conditions, such as central obesity, hypertension, metabolic syndrome and diabetes mellitus type 2, and their cardiovascular sequelae observed in the Kingdom.     

Breastfeeding and Snoring: A Birth Cohort Study

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.     

Snoring, inflammatory markers, adipokines and metabolic syndrome in apparently healthy Chinese

Objective

Chronic low-grade inflammation and adipokines dysregulation are linked to mechanisms underscoring the pathogenesis of obesity-related metabolic disorders. Little is known about roles of these cytokines on the association between snoring and metabolic syndrome (MetS). We aimed to investigate whether a cluster of cytokines are related to snoring frequency and its association with MetS in apparently healthy Chinese.

Methods

Current analyses used a population-based sample including 1059 Shanghai residents aged 35–54 years. Self-reported snoring frequency was classified as never, occasionally and regularly. Fasting plasma glucose, lipid profile, insulin, C-reactive protein, interleukin-6, interleukin-18, lipopolysaccharide binding protein, high-molecular-weight adiponectin and leptin were measured. MetS was defined by the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian-Americans.

Results

Overweight/obese subjects had significantly higher prevalence of regular snorers than their normal-weight counterparts (34.8% vs. 11.5%, P<0.001). Regular snoring was associated with unfavorable profile of inflammatory markers and adipokines. However, those associations were abolished after adjustment for body mass index (BMI) or waist circumference. The MetS risk (multivariate-adjusted odds ratio 5.41, 95% confidence interval 3.72–7.88) was substantially higher in regular snorers compared with non-snorers. Controlling for BMI remarkably attenuated the association (2.03, 1.26–3.26), while adjusting for inflammatory markers and adipokines showed little effects.

Conclusion

Frequent snoring was associated with an elevated MetS risk independent of lifestyle factors, adiposity, inflammatory markers and adipokines in apparently healthy Chinese. Whether snoring pattern is an economic and no-invasive indicator for screening high-risk persons needs to be addressed prospectively.     

Insomnia and Relationship with Anxiety in University Students: A Cross-Sectional Designed Study

Purpose

Sleep disorders (SDs) are now recognized as a public health concern with considerable psychiatric and societal consequences specifically on the academic life of students. The aims of this study were to assess SDs in a group of university students in Lebanon and to examine the relationship between SDs and anxiety.

Methods

An observational cross-sectional study was conducted at Saint-Joseph University, Lebanon, during the academic year 2013–2014. Four questionnaires were face-to-face administered to 462 students after obtaining their written consent: Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Generalized Anxiety Disorder 7-item scale (GAD-7).

Results

The prevalence of clinically significant insomnia was 10.6% (95% CI: 7.8–13.4%), more frequent in first year students. ISI mean score was 10.06 (SD = 3.76). 37.1% of the participants were poor sleepers. Excessive daytime sleepiness (EDS) and poor sleep were significantly more frequent among participants with clinical insomnia (p = 0.031 and 0.001 respectively). Clinically significant anxiety was more frequent in students suffering from clinical insomnia (p = 0.006) and in poor sleepers (p = 0.003). 50.8% of the participants with clinically significant anxiety presented EDS versus 30.9% of those with no clinically significant anxiety (p<0.0001).

Conclusions

The magnitude of SDs in this sample of Lebanese university students demonstrate the importance of examining sleep health in this population. Moreover, the link between SD and anxiety reminds us of the importance of treating anxiety as soon as detected and not simply targeting the reduction of sleep problems.     

Hawthorne Effect with Transient Behavioral and Biochemical Changes in a Randomized Controlled Sleep Extension Trial of Chronically Short-Sleeping Obese Adults: Implications for the Design and Interpretation of Clinical Studies

Objective

To evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.

Design

Subjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.

Setting

Outpatient.

Patients

Obese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.

Intervention

Non-pharmacological sleep extension.

Measurements

Sleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.

Results

Prior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.

Limitations

Relatively small sample size.

Conclusions

Improvements in biochemical and behavioral parameters between screening and randomization changed the “true” study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the “Hawthorne effect”, according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00261898","term_id":"NCT00261898"}}NCT00261898.     

Long-Term Impact of Earthquakes on Sleep Quality

Purpose

We investigated the impact of the 6.3 magnitude 2009 L’Aquila (Italy) earthquake on standardized self-report measures of sleep quality (Pittsburgh Sleep Quality Index, PSQI) and frequency of disruptive nocturnal behaviours (Pittsburgh Sleep Quality Index-Addendum, PSQI-A) two years after the natural disaster.

Methods

Self-reported sleep quality was assessed in 665 L’Aquila citizens exposed to the earthquake compared with a different sample (n = 754) of L''Aquila citizens tested 24 months before the earthquake. In addition, sleep quality and disruptive nocturnal behaviours (DNB) of people exposed to the traumatic experience were compared with people that in the same period lived in different areas ranging between 40 and 115 km from the earthquake epicenter (n = 3574).

Results

The comparison between L’Aquila citizens before and after the earthquake showed a significant deterioration of sleep quality after the exposure to the trauma. In addition, two years after the earthquake L''Aquila citizens showed the highest PSQI scores and the highest incidence of DNB compared to subjects living in the surroundings. Interestingly, above-the-threshold PSQI scores were found in the participants living within 70 km from the epicenter, while trauma-related DNBs were found in people living in a range of 40 km. Multiple regressions confirmed that proximity to the epicenter is predictive of sleep disturbances and DNB, also suggesting a possible mediating effect of depression on PSQI scores.

Conclusions

The psychological effects of an earthquake may be much more pervasive and long-lasting of its building destruction, lasting for years and involving a much larger population. A reduced sleep quality and an increased frequency of DNB after two years may be a risk factor for the development of depression and posttraumatic stress disorder.     

Sleep Quality of Patients with Differentiated Thyroid Cancer

Objective

We aimed to measure prevalence of sleep disturbance in patients with differentiated thyroid cancer (DTC) by calculating Pittsburgh Sleep Quality Index (PSQI), and compare these data with patients with benign thyroid nodules or normal participants.

Methods

Three groups of patients participated in this cross-sectional study. In the first group, 162 patients with DTC received total thyroidectomy, and then ¹³¹I therapy. The second group consisted of 84 patients with benign thyroid nodules, who received partial thyroidectomy. The third group was 78 normal healthy control cases. PSQI was used to assess the sleep quality. Inter-group differences were analyzed by Kruskal-Wallis test or independent samples T test. χ² test was also used to check prevalence differences of poor sleep quality among the groups. Differences of PSQI score and poor sleep quality prevalence before and after ¹³¹I therapy in the same group of DTC participants were analyzed by paired T test and Mcnemar''s test.

Results

Higher PSQI score (7.59 ± 4.21) and higher rate of poor sleep quality (54.32%) were shown in DTC patients than in any other group. After ¹³¹I therapy, PSQI score and prevalence of poor sleep quality in DTC patients increased significantly to 8.78 ± 4.72 and 70.99%. Then DTC patients were divided into two subgroups based on their metastatic status. DTC patients with metastasis (87/162 cases, 53.70%) had significantly higher PSQI score (10.87 ± 5.18) and higher prevalence of poor sleep quality (79.31%).

Conclusion

DTC patients suffer from sleep disturbance, ¹³¹I therapy and awareness of metastatic status could worsen sleep problem. Psychological fear of cancer, nuclear medicine therapy and metastasis could be one major underlying reason. Longitude and interventional studies are necessary for further investigations.     

The association between self‐reported sleep quality and overweight in a Chinese population

Objective:

Sleep quality and obesity are associated with type 2 diabetes, hypertension, and metabolic syndrome. However, there is limited research on the association between sleep quality and obesity, and thus the aim of this study is to investigate this relationship in a Chinese population.

Design and Methods:

Subjects were recruited from the Prevention Health Center of National Cheng Kung University Hospital. Anthropometric data and metabolic parameters were measured. Being overweight or obese was defined according to the recommendations of the Department of Health in Taiwan. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI).

Results:

Of the total 2,803 subjects, 1,059 were classified as normal weight, 1,127 were overweight, and 617 were obese. The global PSQI score were 6.30 ± 2.56, 6.61 ± 2.96, and 7.02 ± 2.95 in subjects who were normal weight, overweight, and obese, respectively (test for trend, P < 0.001). Of the variables tested in the multivariate linear regression model, female gender, being overweight, obesity, sleep duration, and alcohol drinking were significantly associated with global PSQI scores, and in the multivariate logistic regression model, female gender, being overweight, obesity, and sleep duration were independent predictors of poor sleepers after controlling for age, gender, BMI or different weight statuses, sleep duration, alcohol drinking, smoking, habitual exercise, hypertension, newly diagnosed diabetes, total cholesterol, high‐density lipoprotein, triglyceride, estimated glomerular filtration rate, and alanine aminotransferase.

Conclusions:

In conclusion, female gender, being overweight, obesity, and sleep duration were associated with poor sleep quality independent of cardiometabolic risk factors. In clinical practice, subjects who are obese, or even only overweight, should be evaluated for the presence of sleep disturbance.     

Early life environment and snoring in adulthood

Background

To our knowledge, no studies of the possible association of early life environment with snoring in adulthood have been published. We aimed to investigate whether early life environment is associated with snoring later in life.

Methods

A questionnaire including snoring frequency in adulthood and environmental factors in early life was obtained from 16,190 randomly selected men and women, aged 25–54 years, in Sweden, Norway, Iceland, Denmark and Estonia (response rate 74%).

Results

A total of 15,556 subjects answered the questions on snoring. Habitual snoring, defined as loud and disturbing snoring at least 3 nights a week, was reported by 18%. Being hospitalized for a respiratory infection before the age of two years (adjusted odds ratio (OR) = 1.27; 95% confidence interval (CI) 1.01–1.59), suffering from recurrent otitis as a child (OR = 1.18; 95%CI 1.05–1.33), growing up in a large family (OR = 1.04; 95%CI 1.002–1.07) and being exposed to a dog at home as a newborn (OR = 1.26; 95%CI 1.12–1.42) were independently related to snoring later in life and independent of a number of possible confounders in adulthood. The same childhood environmental factors except household size were also related with snoring and daytime sleepiness combined.

Conclusion

The predisposition for adult snoring may be partly established early in life. Having had severe airway infections or recurrent otitis in childhood, being exposed to a dog as a newborn and growing up in a large family are environmental factors associated with snoring in adulthood.     

Specific EEG Sleep Pattern in the Prefrontal Cortex in Primary Insomnia

Objective

To assess the specific prefrontal activity in comparison to those in the other main cortical areas in primary insomnia patients and in good sleepers.

Methods

Fourteen primary insomnia patients and 11 good sleepers were included in the analysis. Participants completed one night of polysomnography in the sleep lab. Power spectra were calculated during the NREM (Non-rapid eyes movements) and the REM (Rapid eyes movements) sleep periods at prefrontal, occipital, temporal and central electrode positions.

Results

During the NREM sleep, the power spectra did not differ between groups in the prefrontal cortex; while primary insomnia patients exhibited a higher beta power spectrum and a lower delta power spectrum compared to good sleepers in other areas. During the REM sleep, the beta1 power spectrum was lower in the prefrontal cortex in primary insomnia patients compared to good sleepers; while no significant difference between groups was obtained for the other areas.

Conclusions

The present study shows a specific prefrontal sleep pattern during the whole sleep period. In addition, we suggest that primary insomnia patients displayed a dysfunction in the reactivation of the limbic system during the REM sleep and we give additional arguments in favor of a sleep-protection mechanism displayed by primary insomnia patients.     

Serum Myostatin Is Reduced in Individuals with Metabolic Syndrome

Aims

Myostatin is a negative regulator of skeletal muscle mass and may also modulate energy metabolism secondarily. We aim to investigate the relationship between serum myostatin and the metabolic variables in diabetic (DM) and non-diabetic subjects.

Materials and Methods

A cross-sectional study recruiting 246 consecutive DM patients and 82 age- and gender-matched non-diabetic individuals at a medical center was conducted. The variables of anthropometry and blood chemistry were obtained. Serum myostatin level was measured with enzyme immunoassay.

Results

DM group had lower serum myostatin compared with non-diabetics (7.82 versus 9.28 ng/ml, p<0.01). Sixty-two percent of the recruited individuals had metabolic syndrome (MetS). The patients with MetS had significantly lower serum myostatin than those without (7.39 versus 9.49 ng/ml, p<0.001). The serum myostatin level decreased with increasing numbers of the MetS components (p for trend<0.001). The patients with higher body mass index, larger abdominal girth, lower high-density lipoprotein cholesterol (HDL-C), and higher triglycerides had lower serum myostatin than those without. The serum myostatin level was independently negatively related to larger abdominal girth, higher triglycerides, and lower HDL-C after adjustment. The odds ratios for MetS, central obesity, low HDL-C, high triglycerides, and DM were 0.85, 0.88, 0.89, 0.85, and 0.92, respectively, when serum myostatin increased per 1 ng/mL, in the binary logistic regression models.

Conclusions

Lower serum myostatin independently associated with MetS, central obesity, low HDL-C, and high triglycerides after adjustment. Higher serum myostatin is associated with favorable metabolic profiles.     

Automatic Detection of Whole Night Snoring Events Using Non-Contact Microphone

Objective

Although awareness of sleep disorders is increasing, limited information is available on whole night detection of snoring. Our study aimed to develop and validate a robust, high performance, and sensitive whole-night snore detector based on non-contact technology.

Design

Sounds during polysomnography (PSG) were recorded using a directional condenser microphone placed 1 m above the bed. An AdaBoost classifier was trained and validated on manually labeled snoring and non-snoring acoustic events.

Patients

Sixty-seven subjects (age 52.5±13.5 years, BMI 30.8±4.7 kg/m², m/f 40/27) referred for PSG for obstructive sleep apnea diagnoses were prospectively and consecutively recruited. Twenty-five subjects were used for the design study; the validation study was blindly performed on the remaining forty-two subjects.

Measurements and Results

To train the proposed sound detector, >76,600 acoustic episodes collected in the design study were manually classified by three scorers into snore and non-snore episodes (e.g., bedding noise, coughing, environmental). A feature selection process was applied to select the most discriminative features extracted from time and spectral domains. The average snore/non-snore detection rate (accuracy) for the design group was 98.4% based on a ten-fold cross-validation technique. When tested on the validation group, the average detection rate was 98.2% with sensitivity of 98.0% (snore as a snore) and specificity of 98.3% (noise as noise).

Conclusions

Audio-based features extracted from time and spectral domains can accurately discriminate between snore and non-snore acoustic events. This audio analysis approach enables detection and analysis of snoring sounds from a full night in order to produce quantified measures for objective follow-up of patients.     

Cephalometric Pattern and Nasal Patency in Children with Primary Snoring: The Evidence of a Direct Correlation

Introduction

Sleep disordered breathing (SDB) might affect craniofacial growth and children with obstructive sleep apnea syndrome present an increase in total and lower anterior heights of the face and a more anterior and inferior position of the hyoid bone when compared to nasal breathers.

Objective

To investigate the correlation between rhinomanometric and cephalometric parameters in children with primary snoring (PS), without apnea or gas exchange abnormalities.

Materials and Methods

Thirty children with habitual snoring (16 females and 14 males) aged 4–8 years (mean age 6.85±1.51 years) were selected by a SDB validate questionnaire. All subjects underwent lateral cephalometric, panoramic radiographies.

Results

In our sample 10 children (33%) had snoring 3 nights/week, 11 (37%) 4–6 nights/week and 9 (30%) every night/week. Overall 7 patients (23.3%) were affected by adenoid hypertrophy (AH), 4 (13.3%) by tonsillar hypertrophy (TH) and 13 (43.3%) by AH and TH. We found a more vertical position of the hyoid bone to the mandibular plane (H⊥VT) in patients with a higher frequency (7.3±2.7 vs 7.6±3.7 vs 10.9±2.5 in children snoring 3 nights/week, 4–6 nights/week and every night/week respectively; p = 0.032). Concerning nasal patency significant correlations were found with ANB (maxillary and jaw position with respect to the cranial base), NS∧Ar (growth predictor), sumangle, FMA (total divergence), SnaSnp∧GoMe (inferior divergence), BaN∧PtGn (facial growth pattern), Phw1_PsP (posterosuperior airway space), AHC3H (the horizontal distance between the most anterosuperior point of the hyoid bone and the third cervical vertebra).

Conclusion

The present study supports the relationship between nasal obstruction and specific craniofacial characteristics in children with primary snoring and lead us to hypothesize that nasal obstruction might explain the indirect link between snoring and cephalometric alterations.     

Seasonal changes in mood and behavior are linked to metabolic syndrome

Background

Obesity is a major public health problem worldwide. Metabolic syndrome is a risk factor to the cardiovascular diseases. It has been reported that disruptions of the circadian clockwork are associated with and may predispose to metabolic syndrome.

Methodology and Principal Findings

8028 individuals attended a nationwide health examination survey in Finland. Data were collected with a face-to-face interview at home and during an individual health status examination. The waist circumference, height, weight and blood pressure were measured and samples were taken for laboratory tests. Participants were assessed using the ATP-III criteria for metabolic syndrome and with the Seasonal Pattern Assessment Questionnaire for their seasonal changes in mood and behavior. Seasonal changes in weight in particular were a risk factor of metabolic syndrome, after controlling for a number of known risk and potential confounding factors.

Conclusions and Significance

Metabolic syndrome is associated with high global scores on the seasonal changes in mood and behavior, and with those in weight in particular. Assessment of these changes may serve as a useful indicator of metabolic syndrome, because of easy assessment. Abnormalities in the circadian clockwork which links seasonal fluctuations to metabolic cycles may predispose to seasonal changes in weight and to metabolic syndrome.