The Epworth sleepiness scale may have more advantages than the multiple sleep latency test in assessing sleepiness in patients with obstructive sleep apnea.

This study aimed to analyze the brain function of severe obstructive sleep apnea patients with various sleepiness assessment methods and explore the brain imaging basis for the differences between these methods. This study included 30 severe obstructive sleep apnea patients and 19 healthy controls. Obstructive sleep apnea patients were divided into a subjective excessive daytime sleepiness group and a subjective non-excessive daytime sleepiness group according to the Epworth sleepiness scale. Moreover, they were divided into an objective excessive daytime sleepiness group and an objective non-excessive daytime sleepiness group according to the multiple sleep latency test. The fractional amplitude of low-frequency fluctuation was used to assess the features of brain function. Compared with healthy controls, participants in the subjective excessive daytime sleepiness group exhibited higher fractional amplitude of low-frequency fluctuation signals in the right thalamus, left cerebellar lobe 6, left putamen, and pallidum. Participants in the objective excessive daytime sleepiness group showed higher fractional amplitude of low-frequency fluctuation signals in the right thalamus and lower fractional amplitude of low-frequency fluctuation signals in the right superior frontal gyrus, the dorsolateral and superior frontal gyrus, and the medial orbital. We concluded that the thalamus may be involved in subjective and objective sleepiness regulation. Functional abnormalities in the putamen and pallidum may be involved in subjective sleepiness, whereas the frontal lobe may be involved in objective sleepiness.

Unrefreshing naps and sleep architecture during the multiple sleep latency test in idiopathic hypersomnia.

Patients with idiopathic hypersomnia frequently report having unrefreshing naps. However, whether they have abnormal sleep architecture during naps that may explain their unrefreshing aspect is unknown. We compared sleep architecture during short daytime naps in patients with idiopathic hypersomnia reporting unrefreshing and refreshing naps. One-hundred and thirty-four patients tested with one-night polysomnography, followed by an adapted version of the Multiple Sleep Latency Test with four naps, were included. They were asked about the refreshing aspect of their habitual naps during a clinical interview. They were classified as having objective (Multiple Sleep Latency Test ≤ 8 min) or subjective idiopathic hypersomnia (Multiple Sleep Latency Test > 8 min), and as presenting refreshing or unrefreshing naps. We tested Group differences (refreshing versus unrefreshing naps) on nap sleep architecture in the whole sample and for subjective and objective idiopathic hypersomnia subgroups separately using ANCOVAs. No Group effects were observed in the Multiple Sleep Latency Test architecture in the whole sample and in objective and subjective idiopathic hypersomnia subgroups. This study provides preliminary evidence that reporting unrefreshing naps is not associated with clinically significant findings in Multiple Sleep Latency Test sleep architecture in patients with idiopathic hypersomnia. Given that naps taken by patients with idiopathic hypersomnia are typically long, future studies should investigate longer daytime sleep episodes.

Sleepiness and comorbid sleep disorders in functional motor disorders: a comparative study with central hypersomnia.

Sleep symptoms, including excessive sleepiness, are frequently reported by patients with functional motor disorders (FMD). We aimed to classify the comorbid sleep disorders in FMD, and to investigate the relationship between subjective sleepiness and objective measures of hypersomnia, comparing them with data from people with central hypersomnia. A total of 37 patients (mean [SD] age 46.4 [11.2] years) with clinically definite FMD, and 17 patients (mean [SD] age 41.1 [11.6] years) with central hypersomnia underwent structured medical and sleep history, neurological examination, polysomnography, multiple sleep latency test (MSLT), and questionnaires assessing sleepiness, fatigue, and depression. In all, 23 patients with FMD (62%) reported excessive daytime sleepiness. Evidence of specific sleep disorders was identified in our cohort, with 35% having restless legs syndrome; 49% obstructive sleep apnea; and 8% periodic limb movements in sleep; however, the presence of these disorders was not correlated with subjective sleepiness. Patients with FMD with self-reported sleepiness reported higher fatigue (p = 0.002), depression (p = 0.002), and had longer sleep latencies in the MSLT (p < 0.001) compared to the patients with central hypersomnia. No correlation was found between subjective and objective sleepiness in either group. Fatigue positively correlated with self-reported sleepiness in patients with FMD (p < 0.001). This study did not find objective correlates of increased sleepiness in patients with FMD. While sleep abnormalities were found to be common in FMD, they were not correlated with self-reports of excessive sleepiness. Positive correlations between self-reported sleepiness and fatigue support the current unified model of non-motor symptoms in FMD.

Clinical and instrumental features in 82 patients with insufficient sleep syndrome.

Insufficient sleep syndrome possibly represents the worldwide leading cause of daytime sleepiness, but remains poorly recognised and studied. The aim of this case series is to comprehensively describe a cohort of patients with insufficient sleep syndrome. Eighty-two patients were studied concerning demographic and socio-economic features, medical, psychiatric and sleep comorbidities, substance use, sleep symptoms, actigraphy, video-polysomnography, multiple sleep latency tests and treatment. The typical patient with insufficient sleep syndrome is a middle-aged adult (with no difference of gender), employed, who has a family, often carrying psychiatric and neurological comorbidities, in particular headache, anxiety and depression. Other sleep disorders, especially mild sleep apnea and bruxism, were common as well. Actigraphy was a valuable tool in the characterisation of insufficient sleep syndrome, showing a sleep restriction during weekdays, associated with a recovery rebound of night sleep during weekends and a high amount of daytime sleep. An over- or underestimation of sleeping was common, concerning both the duration of night sleep and daytime napping. The average daily sleep considering both daytime and night-time, weekdays and weekends corresponds to the recommended minimal normal duration, meaning that the burden of insufficient sleep syndrome could mainly depend on sleep fragmentation and low quality. Sleep efficiency was elevated both in actigraphy and video-polysomnography. Multiple sleep latency tests evidenced a tendency toward sleep-onset rapid eye movement periods. Our study offers a comprehensive characterisation of patients with insufficient sleep syndrome, and clarifies their sleeping pattern, opening avenues for management and treatment of the disorder. Current options seem not adapted, and in our opinion a cognitive-behavioural psychotherapy protocol should be developed.

Sleep-wake cycle and daytime sleepiness in patients with epilepsy after initiating perampanel as adjunctive therapy.

BACKGROUND: Antiseizure medications (ASMs) may affect nocturnal sleep and daytime vigilance. Perampanel (PER), a third-generation ASM, showed to improve nocturnal sleep in patients with epilepsy (PWE). Although ASMs can have beneficial effects on nocturnal sleep and daytime sleepiness, no study investigated the effect of PER on both sleep-wake cycle and daytime sleepiness. Therefore, this study aimed to objectively evaluate the sleep-wake cycle and daytime sleepiness in PWE treated with PER as adjunctive therapy. METHODS: This prospective study included adult PWE who received PER as add-on treatment. Sleep-wake cycle was assessed through actigraphic monitoring and daytime sleepiness by the multiple sleep latency test (MSLT) performed at the end of the actigraphic recording. All patients performed both tests at baseline and at 6-month follow-up. RESULTS: Ten patients (mean age: 44.50 ± 22.71 years, 50.0% female) were included. The mean monthly seizure frequency was 3.20 ± 5.94. Six of ten patients started PER as a first add-on treatment. The final PER dose was 5.11 ± 2.02 mg/day, and nine of ten patients achieved seizure freedom at follow-up. There was a significant decrease in mean monthly seizure frequency from baseline to follow-up (p = 0.004). No significant changes were found in the sleep-wake cycle parameters. An increase in sleep latency mean was observed at MSLT at 6-month follow-up (p = 0.005). CONCLUSIONS: This study confirms that adjunctive PER is effective on seizures without pathologically change of the sleep-wake cycle in PWE and can even improve daytime sleepiness. This effect can be mediated by the achievement of seizure control. Therefore, PER may be promising in PWE with sleep disturbances and daytime sleepiness.

Early- and late-onset narcolepsy: possibly two distinct clinical phenotypes.

PURPOSE: To investigate the clinical characteristics and the risk factors associated with excessive daytime sleepiness (EDS) in patients with early- and late-onset narcolepsy. METHODS: Patients with narcolepsy were consecutively recruited. All patients were separated into early- and late-onset groups according to the onset age of disease ≤ 15 and > 15 years, respectively. Demographic, clinical, and sleep parameters were compared between the two groups. Linear regressions were performed to examine the risk factors of subjective and objective EDS in patients with early- and late-onset narcolepsy. RESULTS: A total of 101 patients with narcolepsy (median age at recruitment = 18.0 years) were classified into an early-onset group (67 patients with median age at onset = 12.0 years) and a late-onset group (34 patients with median age at onset = 28.5 years). Compared with early-onset group, late-onset group scored significantly higher on Epworth Sleepiness Scale (ESS), Ullanlinna Narcolepsy Scale (UNS), sleep paralysis, rapid eye movement (REM) sleep behavior disorder (RBD) questionnaire-Hong Kong (all P < 0.050). UNS-cataplexy and sleep paralysis had significantly positive associations with subjective EDS, and N1%, arousal index, and periodic limb movements index were positively associated with objective EDS in the early-onset group (all P < 0.050). However, these associations were not observed in late-onset narcolepsy. CONCLUSION: Late onset narcolepsy had more severe self-reported narcolepsy symptoms. REM sleep related symptoms and disrupted nighttime sleep were associated with EDS in early-onset narcolepsy. These findings suggest that early- and late-onset narcolepsy may represent two distinct phenotypes.

Narcolepsies, update in 2023.

Narcolepsy type 1 (NT1) and type 2 (NT2), also known as narcolepsy with and without cataplexy, are sleep disorders that benefited from major scientific advances over the last two decades. NT1 is caused by the loss of hypothalamic neurons producing orexin/hypocretin, a neurotransmitter regulating sleep and wake, which can be measured in the cerebrospinal fluid (CSF). A low CSF level of hypocretin-1/orexin-A is a highly specific and sensitive biomarker, sufficient to diagnose NT1. Orexin-deficiency is responsible for the main NT1 symptoms: sleepiness, cataplexy, disrupted nocturnal sleep, sleep-related hallucinations, and sleep paralysis. In the absence of a lumbar puncture, the diagnosis is based on neurophysiological tests (nocturnal and diurnal) and the presence of the pathognomonic symptom cataplexy. In the revised version of the International Classification of sleep Disorders, 3rd edition (ICSD-3-TR), a sleep onset rapid eye movement sleep (REM) period (SOREMP) (i.e. rapid occurrence of REM sleep) during the previous polysomnography may replace the diurnal multiple sleep latency test, when clear-cut cataplexy is present. A nocturnal SOREMP is very specific but not sensitive enough, and the diagnosis of cataplexy is usually based on clinical interview. It is thus of crucial importance to define typical versus atypical cataplectic attacks, and a list of clinical features and related degrees of certainty is proposed in this paper (expert opinion). The time frame of at least three months of evolution of sleepiness to diagnose NT1 was removed in the ICSD-3-TR, when clear-cut cataplexy or orexin-deficiency are established. However, it was kept for NT2 diagnosis, a less well-characterized disorder with unknown clinical course and absence of biolo biomarkers; sleep deprivation, shift working and substances intake being major differential diagnoses. Treatment of narcolepsy is nowadays only symptomatic, but the upcoming arrival of non-peptide orexin receptor-2 agonists should be a revolution in the management of these rare sleep diseases.

[Effect of Objective Daytime Sleepiness on Heart Rate Variability in Patients With Obstructive Sleep Apnea].

Objective: Excessive daytime sleepiness (EDS) is associated with cardiovascular events in patients with obstructive sleep apnea (OSA). Our study explored the correlation between objective daytime sleepiness assessed with daytime multiple sleep latency tests (MSLT) and heart rate variability (HRV) in OSA patients. The results may provide insight into possible mechanisms underlying increased risk of cardiovascular events in patients with OSA. Methods: A retrospective analysis was conducted with the data of 139 patients with OSA and 35 patients with primary snoring. All subjects underwent polysomnography (PSG) and MSLT at West China Hospital between January 2019 and May 2022. We used mean sleep latency (MSL) to measure the severity of EDS and to categorize OSA patients into three groups, severe EDS, light EDS, and non-EDS, with MSL of less than 5 minutes, 5 to 10 minutes, and greater than 10 minutes as the respective defining criteria for classification. A comparison of sleep structure, clinical characteristics, and HRV parameters was performed in order to evaluate the difference between OSA subgroups with varying levels of objective EDS and the primary snoring group. In addition, we also analyzed the correlation between MSL and HRV parameters. Results: Severe EDS patients had higher values of standard deviation of all N-N intervals (SDNN), total spectral power (TOT), and low-frequency power (LF) as compared to non-EDS patients, which was indicative of sympathetic stimulation ( P<0.05). Additionally, high-frequency power (HF) was also higher in severe EDS patients, which indicated decreased parasympathetic drive. A significantly positive correlation was found between MSL and the values of SDNN, TOT, LF, and HF in OSA patients. Conclusion: OSA patients with objective EDS have elevated sympathetic drive and decreased parasympathetic drive. A positive correlation was found between this change in neural activity and the shortening of MSL.

Differential characteristics of repeated polysomnography and multiple sleep latency test parameters in narcolepsy type 1 and type 2 patients: a longitudinal retrospective study.

PURPOSE: Narcolepsy is a chronic disorder and its phenotype is dichotomized into narcolepsy type 1 (NT1) and narcolepsy type 2 (NT2). The clinical course and pathophysiological mechanisms of these two clinical entities and their differences are not adequately defined. This study aimed to explore the differential longitudinal patterns of polysomnography (PSG) and multiple sleep latency test (MSLT) in NT1 and NT2. METHODS: In this retrospective study demographic characteristics, PSG, and MSLT parameters at baseline and follow-up were compared between NT1 and NT2 patients. Patients with both follow-up MSLT and PSG were selected for sub-group analysis. Baseline and follow-up MSLT and PSG parameters were compared. RESULTS: Of 55 patients with narcolepsy, mean follow-up periods were 7.4 ± 3.5 years for NT1 and 5.5 ± 2.9 for NT2. Demographic data showed increased body mass index and prevalence of sleep paralysis in NT1. Baseline PSG characteristics between NT1 and NT2 showed decreased sleep latency (p = 0.016) and REM latency (p = 0.046) in NT1 group when compared with NT2. Nocturnal SOREMP on PSG was more prevalent in NT1 (p = 0.017), and half of NT2 patients with nocturnal SOREMP on PSG changed their diagnoses to NT1. On follow-up PSG, NT1 displayed reductions in sleep stage N2 (p = 0.006) and N3 (p = 0.048), while wake after sleep onset (WASO) (p = 0.023) and apnea-hypopnea index (AHI) (p = 0.007) were significantly increased. CONCLUSION: Differential MSLT and PSG characteristics of NT1 and NT2 in at baseline and follow-up indicate that NT1 and NT2 are distinct disease phenotypes, and that they present with a contrasting course of disease.

Prevalence of objective excessive daytime sleepiness in a cohort of patients with mild obstructive sleep apnea.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is common, yet the relationship between mild OSA and excessive daytime sleepiness (EDS) is unclear. Our objective was to determine the prevalence of objective EDS in a population with mild OSA using the mean sleep latency (MSL) from the multiple sleep latency test (MSLT). METHODS: We retrospectively analyzed 1205 consecutive patients who underwent a polysomnography and a following day MSLT at a single sleep center. Adult patients who met criteria for mild OSA with an apnea-hypopnea index of 5 to <15 events/h were identified, and the percentage of patients with a MSL ≤ 8 min was determined. Sleep study and demographic variables were examined to evaluate predictors of objective EDS. RESULTS: Of 155 patients with mild OSA, objective EDS was found in 36% (56/155) with an average MSL of 5.6 ± 2.1 min in the objectively sleepy patients. Objectively sleepy patients with mild OSA had greater total sleep time (411.6 ± 48.9 vs. 384.5 ± 61.7 min, p = 0.004), increased sleep efficiency (84.9 ± 9.7 vs. 79.7 ± 12.7%, p = 0.01), and decreased wake after sleep onset time (53.0 ± 36.9 vs. 67.4 ± 46.1 min, p = 0.04) compared to patients with mild OSA but without objective EDS, with total sleep time being an independent predictor of MSL (p = 0.006). The Epworth Sleepiness Scale (ESS) weakly correlated with objective EDS (ρ = - 0.169, p = 0.03). CONCLUSIONS: There is a large subgroup of patients with mild OSA patients who have objective sleepiness. This may represent an ideal subgroup to target for future studies examining the effect of treatment in mild OSA. Additionally, the ESS was a poor predictor of this subgroup with mild OSA and objective EDS.

Diagnosing narcolepsy in the active duty military population.

PURPOSE: Narcolepsy type I and type II are central hypersomnias characterized by excessive daytime sleepiness and nocturnal sleep disruptions. These rare disorders make the diagnosis complex, as multiple sleep disorders are known to cause false-positive results on testing. There is a high incidence of sleep disorders in the military, and the diagnosis of narcolepsy can have serious career implications. This study looked to assess for the presence of confounding disorders in patients previously diagnosed with narcolepsy. METHODS: We conducted a retrospective analysis of patients aged 18-65 previously diagnosed with narcolepsy at an outside facility, referred for repeat evaluation at the Wilford Hall Sleep Disorders Center. Previous test results from the time of original diagnosis were reviewed if available and compared with repeat evaluation which included actigraphy, in-laboratory polysomnography, and multiple sleep latency testing. RESULTS: Of the 23 patients, 2 (9%) retained a diagnosis of narcolepsy after repeat testing. Ten patients (43%) had insufficient sleep syndrome, five (22%) had significant circadian rhythm sleep-wake disorders, and nine (39%) patients were diagnosed with mild obstructive sleep apnea (OSA). Four of the nine patients with OSA (44%) had supine predominant OSA. CONCLUSION: Diagnostic testing for narcolepsy may be influenced by the presence of comorbid sleep disorders including sleep-disordered breathing, insufficient sleep duration, and circadian misalignment which are common in active military personnel. This study emphasizes the importance of excluding these comorbid diagnoses in this population.

Subjective and objective hypersomnia highly prevalent in adults with epilepsy.

INTRODUCTION: Sleepiness is among the most common complaints of people with epilepsy, but objective documentation is lacking. We systematically investigated subjective and objective sleepiness in an observational cross-sectional cohort of adults with epilepsy (AWE). METHODS: This is a prospective study of AWE consecutively recruited without foreknowledge of sleep/wake complaints. Polysomnography (PSG) with 18-channel electroencephalography (EEG) followed by multiple sleep latency testing (MSLT) was performed. Patients completed the Epworth Sleepiness Scale (ESS), a single-item question assessing excessive daytime sleepiness (EDS), and a 7-day sleep and seizure diary. Multivariable linear models were used to assess the association between MSLT mean sleep latency (MSL) and interests with adjustment of covariates of interest. Receiver operating characteristics (ROC) analysis was performed to evaluate the discrimination capability of ESS on MSL < 8 min and <5 min and investigate the optimal cutpoints. RESULTS: Among 127 AWE (mean age: 38.7 ±â€¯13.7 years), abnormal MSL (<8 min) was observed in 49.6% and MSL <5 min in 31.5%. While 78% reported feeling sleepy during the day on a single-item question, only 24% had elevated scores on the ESS (>10/24). The ESS score was associated with MSL even after adjusting for seizure frequency, antiseizure medication (ASM) standardized dose and number, age, gender, depression and insomnia symptom severity, and apnea-hypopnea index (HPI) and total sleep time on PSG (coefficients [95% confidence interval (CI)]: -0.26 [-0.48, -0.05], p = 0.018). The area under the curve (AUC) of the ESS ROC predicting MSL < 8 min and MSL < 5 min were similar: 0.62 (95%CI: 0.52-0.72) and 0.62 (95%CI: 0.51-0.74). CONCLUSIONS: This is the largest prospective cross-sectional observational study to date using MSLT in AWE. We found subjective and objective daytime sleepiness highly prevalent in AWE and not explained by seizure frequency, ASM burden, symptoms of insomnia/depression, or PSG findings although those with MSL < 5 min were more likely to have obstructive sleep apnea (OSA). Pathologic sleepiness with MSL < 8 min was present in half of AWE. Nearly one-third of AWE unselected for sleep/wake complaints had MSL < 5 min, a range typical of narcolepsy.

Residual excessive daytime sleepiness in patients with obstructive sleep apnea treated with positive airway pressure therapy.

PURPOSE: Patients with obstructive sleep apnea (OSA) commonly report residual excessive daytime sleepiness (EDS) despite treatment with positive airway pressure (PAP). The present study aimed to determine whether patients presenting with subjective sleepiness after treatment with PAP therapy had objective evidence of residual sleepiness. METHODS: We conducted a retrospective analysis of 29 adults with OSA on PAP therapy who underwent a standardized evaluation for EDS. Patients were evaluated with the Epworth Sleepiness Scale (ESS) and attend an in-lab polysomnogram (PSG) with PAP followed by a multiple sleep latency test (MSLT). RESULTS: Our cohort consisted of 23 men (79%) and 6 women (21%) with a mean age of 40.7 years. All patients were subjectively sleepy with an ESS score of > 10 and met minimal PAP usage of 4 h a night for at least 70% of nights with a residual apnea-hypopnea index (AHI) ≤ 10. On MSLT, 31% of patients had an average sleep onset latency (SOL) < 8 min, 35% had a SOL between 8 and 11 min, and 35% had SOL > 11 min. CONCLUSION: After optimizing PAP therapy and sleep in patients with OSA and residual EDS, the majority were found to have objective findings of an abnormally short SOL on MSLT. This is further evidence that there is a distinct OSA phenotype that will have persistent EDS despite appropriate treatment of their sleep-disordered breathing. Objective testing to quantify the degree of sleepiness is recommended for OSA patients with residual EDS.

Inside the clinical evaluation of sleepiness: subjective and objective tools.

PURPOSE: To critically review the available tools for evaluating excessive daytime sleepiness (EDS) in clinical practice. METHODS: Objective tests and subjective scales were divided into three groups in accordance with the different dimensions of sleepiness they measure, namely physiological, manifest, and introspective. Strengths, weaknesses, and limitations of each test have been analysed and discussed along with the available recommendations for their use in clinical practice. RESULTS: The majority of the tests developed for sleepiness evaluation do not have practical usefulness outside the research setting. The suboptimal correlation between different tests mainly depends on the different dimensions of sleepiness they analyse. Most importantly in-laboratory tests poorly correlate with sleepiness in real-life situations and, to date, none is able to predict the risk of injuries related to EDS, especially on an individual level. CONCLUSIONS: There exists not the one best test to assess EDS, however, clinicians can choose a more specific test to address a specific diagnostic challenge on the individual level. The development of novel performance tests with low cost and easy to administer is advisable for both screening purposes and fitness for duty evaluations in populations at high risk of EDS-related injuries, for example professional drivers.

Sleep parameters associated with long-term outcome following subthalamic deep brain stimulation in Parkinson's disease.

INTRODUCTION: We aimed to investigate the effects of changes in sleep architecture on long-term clinical outcome in patients with Parkinson's disease (PD) who underwent deep brain stimulation of subthalamic nuclei (STN DBS). METHODS: We followed up eight PD patients before and three years after STN DBS surgery. In addition to clinical assessments, polysomnography (PSG) followed by multiple sleep latency tests was performed before and after STN DBS, while stimulator was ON and OFF. RESULTS: Subjective sleep latency was significantly decreased (P=0.033) and sleep duration was increased (P=0.041), as measured by Pittsburgh sleep quality index. Latency to REM sleep stage was shortened after surgery with STN DBS ON (P=0.002). Index of central type of abnormal respiratory events was significantly increased while stimulator was ON (P=0.034). Total number of major body movements was found to be increased when stimulator was turned OFF (P=0.012). Among PSG data obtained during STN DBS ON, it was observed that duration of N3 sleep was negatively correlated with UPDRS scores at 1st (P=0.038) and 3rd (P=0.045) post-operative years. Among PSG variables during STN DBS OFF, durations of N3 sleep (P=0.017) and REM sleep (P=0.041) were negatively correlated with UPDRS scores at post-operative 1st year. CONCLUSION: Disturbances in sleep architecture are associated with higher UPDRS scores and worse prognosis at 1st and 3rd post-operative years. Similar results obtained while stimulator was OFF at the end of 1st year support the presence of microlesion effect after STN DBS, which is probably not long lasting.

Automatic artefact detection in single-channel sleep EEG recordings.

Quantitative electroencephalogram analysis (e.g. spectral analysis) has become an important tool in sleep research and sleep medicine. However, reliable results are only obtained if artefacts are removed or excluded. Artefact detection is often performed manually during sleep stage scoring, which is time consuming and prevents application to large datasets. We aimed to test the performance of mostly simple algorithms of artefact detection in polysomnographic recordings, derive optimal parameters and test their generalization capacity. We implemented 14 different artefact detection methods, optimized parameters for derivation C3A2 using receiver operator characteristic curves of 32 recordings, and validated them on 21 recordings of healthy participants and 10 recordings of patients (different laboratory) and considered the methods as generalizable. We also compared average power density spectra with artefacts excluded based on algorithms and expert scoring. Analyses were performed retrospectively. We could reliably identify artefact contaminated epochs in sleep electroencephalogram recordings of two laboratories (healthy participants and patients) reaching good sensitivity (specificity 0.9) with most algorithms. The best performance was obtained using fixed thresholds of the electroencephalogram slope, high-frequency power (25-90 Hz or 45-90 Hz) and residuals of adaptive autoregressive models. Artefacts in electroencephalogram data can be reliably excluded by simple algorithms with good performance, and average electroencephalogram power density spectra with artefact exclusion based on algorithms and manual scoring are very similar in the frequency range relevant for most applications in sleep research and sleep medicine, allowing application to large datasets as needed to address questions related to genetics, epidemiology or precision medicine.

Clinical Sleep-Wake Disorders I: Focus on Hypersomnias and Movement Disorders During Sleep.

Central disorders of hypersomnolence are characterized by daily periods of irrepressible need to sleep or daytime lapses into sleep, as defined in the current version of the International Criteria of Sleep Disorders. Thus, the unifying symptom is excessive daytime sleepiness which is not caused by any other sleep-wake disorder. Relevant disorders including narcolepsy type 1 and 2, idiopathic hypersomnia, Kleine-Levin syndrome, and insufficient sleep syndrome will be discussed. Other central disorders of hypersomnolence include hypersomnias due to medical or psychiatric disorders or because of medication or substance use.In sleep-related movement disorders, the cardinal symptom consists of simple, often stereotyped movements occurring during sleep. The most frequent disorder in this category of sleep-wake disorders is restless legs syndrome, which is often associated with period limb movements during sleep.

Multiple sleep latency test in narcolepsy type 1 and narcolepsy type 2: A 5-year follow-up study.

Excessively sleepy teenagers and young adults without sleep-disordered breathing are diagnosed with either narcolepsy type 1 or narcolepsy type 2, or hypersomnia, based on the presence/absence of cataplexy and the results of a multiple sleep latency test. However, there is controversy surrounding this nomenclature. We will try to find the differences between different diagnoses of hypersomnia from the results of the long-term follow-up evaluation of a sleep study. We diagnosed teenagers who had developed excessive daytime sleepiness based on the criteria of the International Classification of Sleep Disorders, 3rd edition. Each individual received the same clinical neurophysiologic testing every year for 5 years after the initial diagnosis of narcolepsy type 1 (n = 111) or type 2 (n = 46). The follow-up evaluation demonstrated that narcolepsy type 1 (narcolepsy-cataplexy) is a well-defined clinical entity, with very reproducible clinical neurophysiologic findings over time, whereas patients with narcolepsy type 2 presented clear clinical and test variability. By the fifth year of the follow-up evaluation, 17.6% of subjects did not meet the diagnostic criteria of narcolepsy type 2, and 23.9% didn't show any two sleep-onset rapid eye movement periods in multiple sleep latency during the 5-year follow-up. Therefore narcolepsy type 1 (narcolepsy-cataplexy) is a well-defined syndrome, with the presentation clearly related to the known consequences of destruction of hypocretin/orexin neurons. Narcolepsy type 2 covers patients with clinical and test variability over time, thus bringing into question the usage of the term "narcolepsy" to label these patients.

Short-term trigeminal neuromodulation does not alter sleep latency in healthy subjects: a pilot study.

It has been reported that during and/or after acute trigeminal nerve stimulation (TNS) a state of sedation, decreased attention and vigilance, with a tendency to fall asleep, occurs. Whether these effects are due to a hypnotic action of TNS is yet to be demonstrated. This pilot study investigates whether acute TNS affects the latency of sleep using the Multiple Sleep Latency Test (MSLT) in healthy subjects. MSLT was performed in 14 healthy subjects after 20 min of real- and a sham-TNS, delivered in two different sessions. Mean latency of sleep across the five naps accorded and the latency of sleep for each nap was determined. All subjects reported a state of relaxation or drowsiness after the real-TNS session. Repeated-measures ANOVA showed no significant differences in sleep latency between the real and sham conditions. The sedative effects of acute TNS do not seem associated to a hypnotic effect.

A four year experience in narcolepsy from a sleep clinic at a tertiary care centre with a short review of contemporary Indian literature.

Narcolepsy is a common sleep disorder in Western countries but rarely reported from India. Here, we report a small case series of four narcolepsy patients seen over a four year period in the sleep clinic of a tertiary care hospital in north India. The diagnosis was established by clinical history and two or more sleep-onset rapid eye movements (SOREMs) on multiple sleep latency tests (MSLTs) following overnight polysomnography (PSG). The mean age of patients was 26.2±6.4 yr; one patient had associated cataplexy and another one had all four cardinal symptoms of narcolepsy. All these patients had a history of excessive daytime sleepiness (EDS). The mean body mass index was 24.2±4.7 kg/m[2]. The mean sleep latency during MSLT was 2.7±1.3 min, and the mean REM latency was 5.7±2.9 min. Narcolepsy, although rarely reported from India, should be suspected in young non-obese patients complaining of EDS and confirmed by performing MSLT following overnight PSG.