Search

Objectives: The objectives of this study were to investigate the relationship between a low libido and objective sleep parameters as well as mood disturbances in patients with obstructive sleep apnea syndrome (OSA)., Methods: We enrolled 436 untreated patients who were newly diagnosed with OSA (all male, mean age 42.8 years). Patients completed the Symptom checklist-90-Revised (SCL-90-R), Epworth Sleepiness Scale (ESS), Beck Depression Inventory-II (BDI), and Beck Anxiety Inventory (BAI). Patients were divided into low-libido and normal-libido groups according to their response to the statement "Loss of sexual interest or pleasure" on the SCL-90-R., Results: Approximately 23% of patients reported a low libido. Patients with a low libido were older (47.5 ± 9.0 vs. 41.4 ± 11.1 years; p < 0.001), had more nocturia (33.3% vs. 16.6%; p < 0.001), higher BDI (9.0 (5.0-14.0) vs. 5.0 (2.0-9.0); p < 0.001) and BAI score (11.0 (6.3-16.8) vs. 5.0 (2.0-10.0); p < 0.001). These patients had a lower non-REM sleep stage 3 (N3) % (0.1 (0-4.0) vs. 2.3 (0.1-7.9); p < 0.001). Multivariate analysis revealed that older age and higher BDI score were independent factors associated with a low libido., Conclusions: Men with untreated OSA suffered from a low libido. Older age and depressed mood were the most important factors of low libido in middle-aged men with OSA., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Purpose: The Munich Chronotype Questionnaire (MCTQ) assesses actual sleep-wake timing and has advantages compared to prior chronotype questionnaires in that it differentiates sleep-wake patterns between work days and free days and uses corrected mid-sleep time on free days after correcting for accumulated sleep debt over the week to categorize chronotype. The current study, we validated the Korean version of the MCTQ., Methods: In this study, 310 participants (mean age = 27.09 ± 5.64; 78.1% females) completed the Korean version of the MCTQ., Results: MCTQ parameters were significantly correlated with MEQ (Morningness-Eveningness Questionnaire) scores (│r│ ≥ 0.48), and test-retest reliability was ≥ 0.72. Cutoff scores of 2.5%, which correlated to 2.36 and 8.57 mid-sleep times in our sample, showed the best convergence with MEQ when categorizing chronotype., Conclusions: Our study suggests that the MCTQ is a useful questionnaire in assessing chronotype in young adults.

Purpose: Although the clinical usefulness of actigraphy (ACT) in chronic insomnia disorder (CID) is extensively investigated, the evaluation on the utility of ACT in sleep-disordered breathing (SDB) is limited and the report of comparison with perceived sleep by patients and polysomnography (PSG) is scarce., Methods: Thirty-six patients with SDB and 30 with CID underwent PSG and ACT, and they reported perceived sleep time and latency simultaneously. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], sleep efficiency, and wakefulness after sleep onset [WASO]) were compared. Agreement among parameters was assessed with intraclass correlation coefficient (ICC) and 95% confidence interval., Results: ACT overestimated TST and underestimated SOL and WASO relative to PSG in both groups. Perceived sleep was commonly undervalued relative to PSG or ACT. In post hoc analyses, perceived sleep was significantly shorter and SOL significantly longer compared to PSG and ACT in both groups. Perception of sleep time by PSG was significantly higher than perception by ACT. In the CID group, all sleep parameters were significantly correlated between ACT and PSG (ICC = 0.627-0.813). In the SDB group, only TST was significantly correlated (ICC = 0.804)., Conclusion: ACT is useful to monitor sleep and sleep quality in patients with CID. In patients with SDB, TST by ACT is reliable. However, ACT is insufficient to assess sleep quality due to its low agreement with PSG. Significantly lower sleep perception relative to PSG and ACT should be considered in the treatment of sleep disorders.

Objective: This paper proposes a method for classifying sleep-wakefulness and estimating sleep parameters using nasal pressure signals applicable to a continuous positive airway pressure (CPAP) device., Approach: In order to classify the sleep-wakefulness states of patients with sleep-disordered breathing (SDB), apnea-hypopnea and snoring events are first detected. Epochs detected as SDB are classified as sleep, and time-domain- and frequency-domain-based features are extracted from the epochs that are detected as normal breathing. Subsequently, sleep-wakefulness is classified using a support vector machine (SVM) classifier in the normal breathing epoch. Finally, four sleep parameters-sleep onset, wake after sleep onset, total sleep time and sleep efficiency-are estimated based on the classified sleep-wakefulness. In order to develop and test the algorithm, 110 patients diagnosed with SDB participated in this study. Ninety of the subjects underwent full-night polysomnography (PSG) and twenty underwent split-night PSG. The subjects were divided into 50 patients of a training set (full/split: 42/8), 30 of a validation set (full/split: 24/6) and 30 of a test set (full/split: 24/6)., Main Results: In the experiments conducted, sleep-wakefulness classification accuracy was found to be 83.2% in the test set, compared with the PSG scoring results of clinical experts. Furthermore, all four sleep parameters showed higher correlations than the results obtained via PSG (r  ⩾  0.84, p  <  0.05). In order to determine whether the proposed method is applicable to CPAP, sleep-wakefulness classification performances were evaluated for each CPAP in the split-night PSG data. The results indicate that the accuracy and sensitivity of sleep-wakefulness classification by CPAP variation shows no statistically significant difference (p  <  0.05)., Significance: The contributions made in this study are applicable to the automatic classification of sleep-wakefulness states in CPAP devices and evaluation of the quality of sleep.

Study Objectives: To investigate whether sleep perception (SP), defined by the ratio of subjective and objective total sleep time, and habitual sleep time in various sleep disorders may be based on comorbid insomnia status., Methods: We enrolled 420 patients (age 20-79 y) who underwent polysomnography (PSG). They were divided into three groups based on chief complaints: chronic insomnia (CI, n = 69), patients with both obstructive sleep apnea and insomnia (OSA-I, n = 49) or OSA only (OSA, n = 149). Healthy volunteers were also recruited (normal controls [NC], n = 80). We compared differences in PSG parameters and habitual sleep duration and investigated the discrepancy between objective and subjective total sleep time (TST) and sleep latency among four groups. Subjective TST was defined as sleep time perceived by participants the next morning of PSG., Results: SP for TST was highest in the OSA group (median 92.9%), and lowest in the CI group (80.3%). SP of the NC group (91.4%) was higher than the CI, but there was no difference between OSA-I and OSA groups. OSA-I had higher depressive mood compared to the OSA group (p < 0.001). SP was positively associated with the presence of OSA and habitual sleep duration and negatively related to the presence of insomnia and arousal index of PSG. Insomnia patients with (OSA-I) or without OSA (CI) reported the smallest discrepancy between habitual sleep duration and objective TST., Conclusions: Patients with OSA with or without insomnia have different PSG profiles, which suggests that objective measures of sleep are an important consideration for differentiating subtypes of insomnia and tailoring proper treatment., Commentary: A commentary on this articles appears in this issue on page 1437., (© 2016 American Academy of Sleep Medicine)

Purpose: Although mounting evidence suggests that sleep and epilepsy are reciprocal and seizures influence circadian rhythms, sleep-wake pattern and seizure control have not been widely researched. This study aimed to investigate the association of sleep-wake pattern, sleep quality, and chronotype with seizures in patients with epilepsy (PWE)., Methods: 160 consecutive PWE (aged 20-49 years, focal epilepsy, FE: generalized epilepsy, GE=127:33) and 130 age-gender matched healthy controls (HC) were enrolled. All subjects completed a sleep diary for more than 2 weeks, Pittsburgh Sleep Quality Index (PSQI), Epworth sleepiness scale (ESS), and the Morningness-Eveningness questionnaire (MEQ). Detailed seizure history was reviewed for the last 1 year., Key Findings: Sleep-wake patterns on workdays were different between PWE and HC (p<0.001), although PSQI, ESS, and MEQ did not differ. Social jetlag (difference of mid-sleep time between workdays and free days) was more evident in PWE (1.4h) than HC (0.7h, p<0.001). GE showed lower MEQ, later mid-sleep time on both workdays and free days, and larger social jetlag than FE. Higher seizure frequency was positively correlated with higher PSQI and ESS after adjusting for age, gender, and number of antiepileptic drugs (p<0.05). PWE with lower MEQ presented worse sleep quality., Significance: Contrary to HC, PWE maintained sleep-wake patterns more regularly during workdays and free days. GE patients reported more eveningness-preference; however, their sleep quality was not worse than FE. Although sleep quality may affect seizure frequency, sleep-wake patterns and chronotype were not related to seizures in PWE., (Copyright © 2015. Published by Elsevier B.V.)

Obesity is a common disorder with many complications. Although chronodisruption plays a role in obesity, few epidemiological studies have investigated the association between artificial light at night (ALAN) and obesity. Since sleep health is related to both obesity and ALAN, we investigated the association between outdoor ALAN and obesity after adjusting for sleep health. We also investigated the association between outdoor ALAN and sleep health. This cross-sectional survey included 8526 adults, 39-70 years of age, who participated in the Korean Genome and Epidemiology Study. Outdoor ALAN data were obtained from satellite images provided by the US Defense Meteorological Satellite Program. We obtained individual data regarding outdoor ALAN; body mass index; depression; and sleep health including sleep duration, mid-sleep time, and insomnia; and other demographic data including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking status and consumption of caffeine or alcohol before sleep. A logistic regression model was used to investigate the association between outdoor ALAN and obesity. The prevalence of obesity differed significantly according to sex (women 47% versus men 39%, p < 0.001) and outdoor ALAN (high 55% versus low 40%, p < 0.001). Univariate logistic regression analysis revealed a significant association between high outdoor ALAN and obesity (odds ratio [OR] 1.24, 95% confidence interval [CI] 1.14-1.35, p < 0.001). Furthermore, multivariate logistic regression analyses showed that high outdoor ALAN was significantly associated with obesity after adjusting for age and sex (OR 1.25, 95% CI 1.14-1.37, p < 0.001) and even after controlling for various other confounding factors including age, sex, educational level, type of residential building, monthly household income, alcohol consumption, smoking, consumption of caffeine or alcohol before sleep, delayed sleep pattern, short sleep duration and habitual snoring (OR 1.20, 95% CI 1.06-1.36, p = 0.003). The findings of our study provide epidemiological evidence that outdoor ALAN is significantly related to obesity.

Objective: This longitudinal study investigated potential positive impact of CPAP treatment on brain health in individuals with obstructive sleep Apnea (OSA). To allow this, we aimed to employ sleep electroencephalogram (EEG)‐derived brain age index (BAI) to quantify CPAP's impact on brain health and identify individually varying CPAP effects on brain aging using machine learning approaches. Methods: We retrospectively analyzed CPAP‐treated (n = 98) and untreated OSA patients (n = 88) with a minimum 12‐month follow‐up of polysomnography. BAI was calculated by subtracting chronological age from the predicted brain age. To investigate BAI changes before and after CPAP treatment, we compared annual ΔBAI between CPAP‐treated and untreated OSA patients. To identify individually varying CPAP effectiveness and factors influencing CPAP effectiveness, machine learning approaches were employed to predict which patient displayed positive outcomes (negative annual ΔBAI) based on their baseline clinical features. Results: CPAP‐treated group showed lower annual ΔBAI than untreated (−0.6 ± 2.7 vs. 0.3 ± 2.6 years, p < 0.05). This BAI reduction with CPAP was reproduced independently in the Apnea, Bariatric surgery, and CPAP study cohort. Patients with more severe OSA at baseline displayed more positive annual ΔBAI (=accelerated brain aging) when untreated and displayed more negative annual ΔBAI (=decelerated brain aging) when CPAP‐treated. Machine learning models achieved high accuracy (up to 86%) in predicting CPAP outcomes. Interpretation. CPAP treatment can alleviate brain aging in OSA, especially in severe cases. Sleep EEG‐derived BAI has potential to assess CPAP's impact on brain health. The study provides insights into CPAP's effects and underscores BAI‐based predictive modeling's utility in OSA management. [ABSTRACT FROM AUTHOR]

Wrist-based respiratory rate (RR) measurement during sleep faces accuracy limitations. This study aimed to assess the accuracy of the RR estimation function during sleep based on the severity of obstructive sleep apnea (OSA) using the Samsung Galaxy Watch (GW) series. These watches are equipped with accelerometers and photoplethysmography sensors for RR estimation. A total of 195 participants visiting our sleep clinic underwent overnight polysomnography while wearing the GW, and the RR estimated by the GW was compared with the reference RR obtained from the nasal thermocouple. For all participants, the root mean squared error (RMSE) of the average overnight RR and continuous RR measurements were 1.13 bpm and 1.62 bpm, respectively, showing a small bias of 0.39 bpm and 0.37 bpm, respectively. The Bland–Altman plots indicated good agreement in the RR measurements for the normal, mild, and moderate OSA groups. In participants with normal-to-moderate OSA, both average overnight RR and continuous RR measurements achieved accuracy rates exceeding 90%. However, for patients with severe OSA, these accuracy rates decreased to 79.45% and 75.8%, respectively. The study demonstrates the GW's ability to accurately estimate RR during sleep, even though accuracy may be compromised in patients with severe OSA. [ABSTRACT FROM AUTHOR]

Background and Objectives: Amyloid-beta protein may lead to sleep disturbance and eventually develop cognitive impairment. Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) is a predictor of neurodegeneration, yet there have been limited studies evaluating the relationship between cognitive decline and amyloid accumulation in iRBD patients. The aim of this study is to investigate the clinical and sleep characteristics of iRBD patients and its association with amyloid deposition. Methods: We enroll 23 iRBD patients (mean age, 65.8 years; male, 73.9%), and their mean history of clinically suspected RBD was 6.5 years. All underwent 18F-flutemetamol amyloid PET completed polysomnography (PSG) and questionnaires. Patients were classified into two groups according to amyloid deposition as amyloid positive and negative. Clinical and sleep parameters were compared between groups and were correlated with amyloid deposition, calculated as a standardized uptake value ratio (SUVR). Results: Four patients (17.4%) were revealed to be amyloid positive, and they showed increased percentage of wake after sleep onset (WASO), stage N1, and stage N2 sleep and worse on the Stroop Word Color Test compared to amyloid negative patients. Global SUVR was correlated with total sleep time, sleep efficiency, WASO, and N1 sleep, and these sleep parameters were associated with a part of default mode network of brains such as orbitofrontal, dorsolateral pre-frontal, and left temporal areas. Conclusion: iRBD patients with amyloid deposition have worse sleep quality than patients without amyloid. Relationship between fragmented sleep and amyloid deposition in the default mode network may be crucial to elucidate the disease progress of iRBD. [ABSTRACT FROM AUTHOR]

Fatigue is a prevalent symptom and major burden in neuroimmunological diseases. In neuromyelitis optica spectrum disorder (NMOSD), a severe autoimmune central nervous system (CNS) inflammatory disease with autoantibodies reactive to aquaporin-4, there are few reports about fatigue and quality of life (QOL). We aimed to evaluate the severity of fatigue and its relationship with QOL in patients with NMOSD. We prospectively studied patients with NMOSD who were in remission and seropositive for anti-aquaporin-4 antibody, and they were divided into 2 groups based on the presence of fatigue assessed using the Functional Assessment of Chronic Illness Therapy-fatigue score. Sleep quality, depression, pain, and QOL were also evaluated. A total of 35 patients were enrolled (mean age, 46.5 ± 14.1 years; female: male = 29:6), and the median Expanded Disability Status Scale (EDSS) score was 2.0 (range, 0 to 8.0). The patients with fatigue (N = 25, 71.4%) had poorer sleep quality and more severe depression than those without fatigue (p = 0.009 and p = 0.001). Both the physical and mental QOL scores were lower in patients with fatigue than in those without fatigue (p = 0.033 and p = 0.004). Multiple linear regression analyses showed that the degree of fatigue with EDSS score and pain were independent predictors of physical aspects of QOL (B = 0.382, p = 0.001), whereas depression was the only predictor of the mental components of QOL (B = -0.845, p = <0.001). Fatigue is a common symptom and an important predictor of QOL in patients with NMOSD. [ABSTRACT FROM AUTHOR]

To investigate the associations between amount of habitual alcohol consumption (HAC) and prevalence of metabolic syndrome (MetS), sleep, and sleep-disordered breathing (SDB). We enrolled 683 untreated SDB male patients (age: 54.4 ± 7.80 y, apnea-hypopnea index (AHI): 29.0 ± 21.53/h). HAC was assessed as the average number of drinks consumed per week during the past 12 months. Anthropometric and biochemical markers were used to diagnose MetS. Clinical data and MetS components were compared according to the reported amounts of HAC (no drinking, light drinking <13, heavy drinking ≥13 drinks/week). As reported, 78.9% of the participants (n = 539) were regular drinkers; 33.7% (n = 230) were habitually heavy drinkers (mean: 30.7 drinks/week), and 45.2% (n = 309) were light drinkers (5.1 drinks/week). The overall prevalence of MetS was 36.9% (n = 252) and was most common in heavy drinkers (40.5%). Compared to non-drinkers and light drinkers, heavy drinkers had the greatest body mass index (BMI) and waist circumference. Central obesity, hypertension, and hyperglycemia were most prevalent in heavy drinkers. Sleep quality and severity of SDB were the worst in heavy drinkers. After adjusting for age, AHI, and BMI, heavy drinkers had a 1.71 times greater risk of MetS when compared with non-drinkers, and light and heavy drinkers had a 2.06 and 2.11 times higher risk of severe SDB than non-drinkers. HAC may increase the prevalence of MetS and deteriorate sleep in relation to amount of alcohol intake. Even light drinkers had more than twice higher risk of severe SDB than non-drinkers. [ABSTRACT FROM AUTHOR]

Nocturnal stridor is a breathing disorder prevalent in patients with multiple system atrophy (MSA). An improved understanding of this breathing disorder is essential since nocturnal stridor carries a poor prognosis (an increased risk of sudden death). In this study, we aimed to classify types of stridor by sound analysis and to reveal their clinical significance. Patients who met the criteria for probable MSA and had undergone polysomnography (PSG) were recruited. Patients were then assessed clinically with sleep questionnaires, including the Pittsburgh Sleep Quality Index, and the Hoehn and Yahr scale. Nocturnal stridor and snoring were analyzed with the Multi-Dimensional Voice Program. Nocturnal stridor was recorded in 22 patients and snoring in 18 patients using the PSG. Waveforms of stridors were classified into rhythmic or semirhythmic after analysis of the oscillogram. Formants and harmonics were observed in both types of stridor, but not in snoring. Of the 22 patients diagnosed with stridor during the present study, fifteen have subsequently died, with the time to death after the PSG study being 1.9 ± 1.4 years (range 0.8 to 5.0 years). The rhythmic waveform group presented higher scores on the Hoehn and Yahr scale and the survival outcome of this group was lower compared to the semirhythmic waveform group (p = 0.030, p = 0.014). In the Kaplan Meier’s survival curve, the outcome of patients with rhythmic waveform was significantly less favorable than the outcome of patients with semirhythmic waveform (log-rank test, p < 0.001). Stridor in MSA can be classified into rhythmic and semirhythmic types and the rhythmic component signifies a poorer outcome. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Artificial lighting has been beneficial to society, but unnecessary light exposure at night may cause various health problems. We aimed to investigate how whole-night bedside light can affect sleep quality and brain activity. Patients and methods: Ten healthy sleepers underwent two polysomnography (PSG) sessions, one with the lights off and one with the lights on. PSG variables related to sleep quality were extracted and compared between lights-off and lights-on sleep. Spectral analysis was performed to rapid eye movement (REM) sleep and non-REM (NREM) sleep epochs to reveal any light-induced differences in background brain rhythms. Results: Lights-on sleep was associated with increased stage 1 sleep (N1), decreased slow-wave sleep (SWS), and increased arousal index. Spectral analysis revealed that theta power (4–8Hz) during REM sleep and slow oscillation (0.5–1Hz), delta (1–4Hz), and spindle (10–16Hz) power during NREM sleep were decreased in lights-on sleep conditions. Conclusions: Sleeping with the light on not only causes shallow sleep and frequent arousals but also has a persistent effect on brain oscillations, especially those implicated in sleep depth and stability. Our study demonstrates additional hazardous effect of light pollution on health. [Copyright &y& Elsevier]

Shift work disrupts circadian rhythms and alters sleep patterns, resulting in various health problems. To quantitatively assess the impact of shift work on brain health, we evaluated the brain age index (BAI) derived from sleep electroencephalography (EEG) results in night-shift workers and compared it with that in daytime workers. We studied 45 female night shift nurses (mean age: 28.2 ± 3.3 years) and 44 female daytime workers (30.5 ± 4.7 years). Sleep EEG data were analyzed to calculate BAI. The BAI of night shift workers who were asleep during the daytime with those of daytime workers who were asleep at night were statistically compared to explore associations between BAI, duration of shift work, and sleep quality. Night-shift workers exhibited significantly higher BAI (2.14 ± 6.04 vs. 0 ± 5.35), suggesting accelerated brain aging and altered sleep architecture, including reduced delta and sigma wave frequency activity during non-rapid eye movement sleep than daytime workers. Furthermore, poor deep sleep quality, indicated by a higher percentage of N1, lower percentage of N3, and higher arousal index, was associated with increased BAI among shift workers. Additionally, a longer duration of night-shift work was correlated with increased BAI, particularly in older shift workers. Night-shift work, especially over extended periods, may be associated with accelerated brain aging, as indicated by higher BAI and alterations in sleep architecture. Interventions are necessary to mitigate the health impacts of shift work. Further research on the long-term effects and potential strategies for sleep improvement and mitigating brain aging in shift workers is warranted. • Night-shift workers exhibited a significantly higher Brain Age Index (BAI) compared to daytime workers. • Poor deep sleep quality during daytime sleep in night-shift workers was associated with increased BAI. • Extended periods of night-shift work were associated with accelerated brain aging. [ABSTRACT FROM AUTHOR]

Sleep technicians are at high risk of shift work sleep disorders. We therefore aimed to identify the optimal shift system for sleep technicians. We performed a nationwide survey of the work schedules, health and quality of life of sleep technicians using e-mail questionnaires including the Insomnia Severity Index (ISI), Epworth Sleep Scale (ESS), Functional Outcomes of Sleep Questionnaire-10 (FOSQ-10), Short Form-12 Health Survey (SF-12), and Hospital Anxiety and Depression Scale (HADS) in Korea. A multivariate general linear model was used to assess the effect of shift schedules on health and quality of life. Fifty-four technicians from 30 sleep laboratories participated. Their work schedules were classified as fixed night (F) (n = 18), slow rotation alternating from a night-only to a day-only schedule with a 3-months to one-year interval (S) (n = 20), rapid rotation within a week (R) (n = 5), night once a week (D+) (n = 5) and day (D) (n = 6). The adjusted ISI and HADS-anxiety scores were higher in F, S, and R than D and D+. Among night shift-dominant schedules, a less favorable profile was observed for R followed by F, and S regarding the ISI, FOSQ-10, mental SF-12 and HADS-depression. The physical SF-12 was lower in the order of R, S and F. The HADS-anxiety score was higher in the order of F, R and S. The S system appears to have the least negative effect on health and quality of life among night shift-dominant systems. The development of consensus guidelines for scheduling shifts in sleep laboratories is urged. • Sleep technicians are at risk of shift work sleep disorder. • Slow rotation system had the least negative effects on health and quality of life. • Consensus guidelines for shift system of sleep laboratories should be developed. [ABSTRACT FROM AUTHOR]