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.

Polysomnographic findings of myotonic dystrophy type 1/type 2: evidence from case-control studies

STUDY OBJECTIVES

This study explores polysomnographic and multiple sleep latency test (MSLT) differences between myotonic dystrophy type 1/type 2 (DM1/DM2) patients and controls.

METHODS

An electronic literature search was conducted in MEDLINE, EMBASE, All EBM databases, and Web of Science from inception to Aug 2023.

RESULTS

Meta-analyses revealed significant reductions in sleep efficiency, N2 percentage, mean SpO2, and MSLT measured mean sleep latency, and increases in N3 sleep, wake time after sleep onset, apnea hypopnea index, and periodic limb movement index in DM1 patients compared with controls. However, any differences of polysomnographic sleep change between DM2 patients and controls could not be established due to limited available studies.

CONCLUSIONS

Multiple significant polysomnographic abnormalities are present in DM1. More case-control studies evaluating polysomnographic changes in DM2 compared with controls are needed.

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.

The Role of Sodium Oxybate in Idiopathic Hypersomnia: A Case Report Showing Improvement of Excessive Daytime Sleepiness and Reduced Symptoms

Our aim is to report the clinical profile and outcome of patients diagnosed with idiopathic hypersomnia (IH). Idiopathic hypersomnolence is a complex, debilitating, and uncommon sleep disorder manifested mainly by chronic excessive daytime sleepiness (EDS). This paper reports on the treatment of a patient with idiopathic hypersomnia who was treated with low sodium oxybate (LXB) due to a lack of response to the first-line drug modafinil. This patient, who presented with worsening excessive daytime sleepiness, sleep drunkenness, and sleep disturbances, was diagnosed with idiopathic hypersomnia by overnight polysomnography (PSG) and a multiple sleep latency test (MSLT). Stimulant agent modafinil was prescribed along with sleep hygiene education. Her symptoms did not respond to modafinil, and she was switched to a recently approved newer medication, i.e., low sodium oxybate.

[Sleep paralysis during naptime as initial symptom of narcolepsy]

INTRODUCTION

Narcolepsy is a disease of unknown etiology, with a very low prevalence (0.02-0.16% in adults, although it must be higher, given the underdiagnosis), characterized by the presence of excessive daytime sleepiness, hypnagogic and/or hypnopompic hallucinations, sleep paralysis and/or cataplexy (if present, we speak of type 1 narcolepsy and, if not, type 2 narcolepsy), whose average diagnostic delay is between 10 and 15 years.

CASE REPORT

A 16-year-old male who consulted after visiting different specialists for presenting sleep paralysis during naps, which cause him fear and occasional objects falling from his hands (diagnosed as possible myoclonus). In the anamnesis we were surprised by the presence of sleep paralysis immediately after the start of the naps and, in the directed anamnesis, these sudden movements caused by emotions were compatible with cataplexies, so we performed a nocturnal polysomnographic study and a multiple sleep latency test. With evolution came hypnopompic hallucinations and fragmented nocturnal sleep, as well as occasional daytime sleepiness (thus completing the typical symptomatic tetrad of type 1 narcolepsy with cataplexy).

CONCLUSION

Knowledge of this disease is important, considering it as a differential diagnosis in patients with episodes of intractable sleepiness, send these patients to expert doctors in sleep disorders and doing a good anamnesis, performing the necessary complementary tests for the diagnosis of this underdiagnosed disease for its correct management, which is decisive for improving the quality of life of these patients.

Progressive narcolepsy: how to deal with intermediate hypocretin-1 values?

According to the International Classification of Sleep Disorders, third edition guidelines, the diagnosis of narcolepsy type 1 is based on the association of excessive daytime sleepiness plus either cataplexy and electrophysiological criteria, or a cerebrospinal fluid hypocretin-1 concentration below 110 pg/mL. This threshold remains debated, and recent works have proposed alternative values in the intermediate (110 to 200 pg/mL) zone. We report the case of a patient who presented with typical clinical symptoms of narcolepsy type 1 developing over six years but in whom initial polysomnography and multiple sleep latency test were negative and cerebrospinal fluid hypocretin-1 was intermediate (132 pg/mL). Cerebrospinal fluid hypocretin-1 reassessment four years later found a dramatic decrease, < 50 pg/mL, and the multiple sleep latency test proved to be abnormal, eventually allowing to confirm the diagnosis. This case highlights the importance of reassessing patients with intermediate hypocretin-1 values and contributes to the debate on the determination of alternative cerebrospinal fluid hypocretin1 thresholds for narcolepsy type 1 diagnosis.

CITATION

Ricordeau F, Bridoux A, Raverot V, Peter-Derex L. Progressive narcolepsy: how to deal with intermediate hypocretin-1 values? J Clin Sleep Med. 2023;19(7):1375-1378.

Rapid eye movement sleep duration during the multiple sleep latency test to diagnose hypocretin-deficient narcolepsy

STUDY OBJECTIVES

To assess the performances of alternative measures of the multiple sleep latency test (MSLT) to identify hypocretin-deficiency in patients with a complaint of hypersomnolence, including patients with narcolepsy.

METHODS

MSLT parameters from 374 drug-free patients with hypersomnolence, with complete clinical and polysomnographic (PSG) assessment and cerebrospinal hypocretin-1 measurement were collected. Conventional (sleep latency, number of sleep onset REM-SOREM-periods) and alternative (sleep duration, REM sleep latency and duration, sleep stage transitions) MSLT measures were compared as function of hypocretin-1 levels (≤110 vs > 110 pg/mL). We performed receiver-operating characteristics analyses to determine the best thresholds of MSLT parameters to identify hypocretin-deficiency in the global population and in subgroups of patients with narcolepsy (i.e. typical cataplexy and/or positive PSG/MSLT criteria, n = 223).

RESULTS

Patients with hypocretin-deficiency had shorter mean sleep and REM sleep latencies, longer mean sleep and REM sleep durations and more direct REM sleep transitions during the MSLT. The current standards of MSLT/PSG criteria identified hypocretin-deficient patients with a sensitivity of 0.87 and a specificity of 0.69, and 0.81/0.99 when combined with cataplexy. A mean REM sleep duration ≥ 4.1 min best identified hypocretin-deficiency in patients with hypersomnolence (AUC = 0.932, sensitivity 0.87, specificity 0.86) and ≥ 5.7 min in patients with narcolepsy (AUC = 0.832, sensitivity 0.77, specificity 0.82).

CONCLUSION

Compared to the current neurophysiological standard criteria, alternative MSLT parameters would better identify hypocretin-deficiency among patients with hypersomnolence and those with narcolepsy. We highlighted daytime REM sleep duration as a relevant neurophysiological biomarker of hypocretin-deficiency to be used in clinical and research settings.

Elevated beta activity in the nighttime sleep and multiple sleep latency electroencephalograms of chronic insomnia patients

Aim

To examine the 24-h hyperarousal hypothesis of insomnia using electroencephalographic (EEG) spectral analysis of overnight polysomnography (PSG) and daytime multiple sleep latency tests (MSLTs).

Methods

Standard PSG and MSLT were recorded in 31 chronic insomniacs (CIs) (21 females, mean age 36.19) and in 21 normal controls (NCs) (18 females, mean age 34.76). EEG spectral analyses were conducted and relative power was obtained for each sleep stage during PSG and each session during MSLTs. Subsequently, CIs were subdivided based on sleep efficiency (SE < or ≥ 85%) or mean sleep latency (MSL) of MSLT (< or ≥ 15 min), and beta power was compared among NCs and CIs subgroups. General liner regression analyses of beta power and PSG parameters were conducted.

Results

CIs had significantly greater beta power in nighttime W, N1, N2, NREM, and in total overnight and in MSLT sessions compared with NCs. CIs with lower PSG-SE or longer MSLT-MSL showed higher beta power at nighttime. Compared with NCs, increased beta power was limited to CIs with lower PSG-SE or longer MSLT-MSL during MSLT sessions. In all subjects, total daytime beta was positively correlated to total overnight beta and MSL, total overnight beta was negatively related to SE. In CIs, total daytime beta and total overnight beta were positively correlated.

Conclusion

Our results support the hypothesis of 24-h cortical hyperarousal in insomnia. We conclude that 24-h cortical hyperarousal is clearly present in insomnia and is greater in insomnia with objective findings.

Central disorders of hypersomnolence: diagnostic discrepancies between military and civilian sleep centers

STUDY OBJECTIVES

The majority of active-duty service members obtain insufficient sleep, which can influence diagnostic evaluations for sleep disorders, including disorders of hypersomnolence. An incorrect diagnosis of hypersomnia may be career ending for military service or lead to inappropriate medical care. This study was conducted to assess the rates at which narcolepsy (Nc) and idiopathic hypersomnia (IH) are diagnosed by military vs civilian sleep disorders centers.

METHODS

This retrospective study utilized claims data from the Military Health System Data Repository. The analyses compared diagnostic rates of military personnel by provider type-either civilian provider or military provider-from January 1, 2016 to December 31, 2019. Three diagnostic categories for Nc and IH: Nc or IH, Nc only, and IH only, were assessed with multivariate logistic regression models.

RESULTS

We found that among service members evaluated for a sleep disorder, the odds ratios of a positive diagnosis at a civilian facility vs a military facility for Nc or IH was 2.1, for Nc only was 2.1, and IH only was 2.0 over the 4-year period.

CONCLUSIONS

Civilian sleep specialists were twice as likely to diagnose central disorders of hypersomnolence compared to military specialists. Raising awareness about this discrepancy is critical given the occupational and patient care-related implications of misdiagnoses.

CITATION

Thomas CL, Vattikuti S, Shaha D, et al. Central disorders of hypersomnolence: diagnostic discrepancies between military and civilian sleep centers. J Clin Sleep Med. 2022;18(10):2433-2441.

Towards an automatic narcolepsy detection on ambiguous sleep staging and sleep transition dynamics joint model

Objective.Mixing/dissociation of sleep stages in narcolepsy adds to the difficulty in automatic sleep staging. Moreover, automatic analytical studies for narcolepsy and multiple sleep latency test (MSLT) have only done automatic sleep staging without leveraging the sleep stage profile for further patient identification. This study aims to establish an automatic narcolepsy detection method for MSLT.Approach.We construct a two-phase model on MSLT recordings, where ambiguous sleep staging and sleep transition dynamics make joint efforts to address this issue. In phase 1, we extract representative features from electroencephalogram (EEG) and electrooculogram (EOG) signals. Then, the features are input to an EasyEnsemble classifier for automatic sleep staging. In phase 2, we investigate sleep transition dynamics, including sleep stage transitions and sleep stages, and output likelihood of narcolepsy by virtue of principal component analysis (PCA) and a logistic regression classifier. To demonstrate the proposed framework in clinical application, we conduct experiments on 24 participants from our hospital, considering ten patients with narcolepsy and fourteen patients with MSLT negative.Main results.Applying the two-phase leave-one-subject-out testing scheme, the model reaches an accuracy, sensitivity, and specificity of 87.5%, 80.0%, and 92.9% for narcolepsy detection. Influenced by disease pathology, accuracy of automatic sleep staging in narcolepsy appears to decrease compared to that in the non-narcoleptic population.Significance.This method can automatically and efficiently distinguish patients with narcolepsy based on MSLT. It probes into the amalgamation of automatic sleep staging and sleep transition dynamics for narcolepsy detection, which would assist clinic and neuroelectrophysiology specialists in visual interpretation and diagnosis.

Narcolepsy type 1 comorbid with Myasthenia Gravis: possible immunological link

Narcolepsy type 1 (NT1) has a probable autoimmune pathophysiology. Myasthenia Gravis (MG) is an auto-antibody mediated neuromuscular junction disorder. In the case reports below we describe two women who were diagnosed with NT1 at ages 33 and 46 respectively. Both have seronegative MG and although the MG was diagnosed earlier than the NT1 the symptoms of both conditions in both women started simultaneously. We discuss the potential mechanism linking these two conditions and the possibility of early detection of NT1 in MG patients.

Reliability and Efficacy of the Epworth Sleepiness Scale: Is There Still a Place for It?

The Epworth sleepiness scale (ESS) is a commonly used questionnaire to evaluate patients for excessive daytime sleepiness (EDS). The ESS has been validated as a measure of EDS, but a number of studies have shown more test-retest variability in clinical settings compared to the original validation study. This observation of higher-than-expected test-retest variability has called into question the utility of the ESS as a clinical tool to assess EDS. The purpose of this review article is to summarize how studies of test-retest variability in clinical populations compare to the original validation study of Johns and to highlight where they differ. Furthermore, use of the ESS as a continuous variable (with no specified cutoff value) versus a categorical variable (normal versus high) is described. These observations are put into a clinical context by comparing the test-retest variability observed on the ESS with that of the multiple sleep latency test (MSLT). Finally, how contributors to ESS scores differ within certain subpopulations is described. The ESS remains an important tool to measure EDS in patient populations, but an awareness of its limitations needs to be considered.

Multimodal assessment increases objective identification of hypersomnolence in patients referred for multiple sleep latency testing

STUDY OBJECTIVES

The multiple sleep latency test (MSLT) has limitations when evaluating disorders of hypersomnolence with unknown etiology. Alternative measures of hypersomnolence may objectively identify pathology in patients with complaints of daytime sleepiness that may not be captured by the MSLT alone. This study evaluated the impact of a multimodal hypersomnolence assessment relative to MSLT in patients with unexplained hypersomnolence.

METHODS

Seventy-five patients with unexplained hypersomnolence were included in the analyzed sample. Polysomnography was performed without prescribed wake time, and the psychomotor vigilance task and pupillographic sleepiness test were completed between MSLT nap opportunities. Presence or absence of hypersomnolence for each assessment was defined using a priori cutpoints. Proportions of patients identified as hypersomnolent using the multimodal assessment relative to MSLT alone were evaluated, as well as the sensitivity and specificity of ancillary hypersomnolence measures relative to MSLT as a gold standard.

RESULTS

The multimodal assessment more than doubled the proportion of patients identified as having objective deficits relative to MSLT ≤ 8 minutes alone. The combination of excessive sleep duration, lapses on the psychomotor vigilance task, and impairments on the pupillographic sleepiness test also had perfect sensitivity in identifying all patients identified as sleepy by the MSLT across 3 different MSLT cutpoints (5, 8, and 10 minutes).

CONCLUSIONS

These data demonstrate the insufficiency of the MSLT as a singular tool to identify objective pathology in persons with unexplained hypersomnolence. Further efforts to refine and standardize multimodal assessments will likely improve diagnostic acumen and research into the causes of these disorders.

Multiple Sleep Latency Test: when are 4 naps enough?

STUDY OBJECTIVES

The Multiple Sleep Latency Test (MSLT) is central to the diagnosis of narcolepsy and idiopathic hypersomnia. This study is the first to assess the impact of a 5-nap protocol on meeting MSLT-derived diagnostic criteria in a general cohort referred for MSLT, without selection bias.

METHODS

Data for all MSLTs performed at 2 tertiary sleep units in Australia between May 2012 and May 2018 were retrospectively assessed for the impact of the fifth nap on mean sleep latency (MSL) and sleep onset rapid eye movement periods.

RESULTS

There were 122 MSLTs included. The MSL was 8.7 ± 5.1 minutes after 4 naps, compared with 9.2 ± 5.2 minutes for 5 naps (P < .0001). In 8 cases, inclusion of the fifth nap changed the MSL to a value above the diagnostic threshold of 8 minutes. There were no instances in which the MSL moved to ≤ 8 minutes based on fifth nap data. A sleep onset rapid eye movement period occurred in the fifth nap in 9 patients and altered the interpretation in 2 cases.

CONCLUSIONS

The fifth nap in an MSLT is associated with an increased MSL, although this difference is rarely clinically significant. In patients with borderline MSL or 1 sleep onset rapid eye movement period after 4 naps, a fifth nap can alter the outcome and should be performed. However, for many cases, a 4-nap MSLT protocol will suffice, potentially allowing resource savings without compromising diagnostic accuracy. We propose the adoption of a conditional 4-nap or 5-nap protocol based on specific criteria.

Case report: early onset narcolepsy initially misdiagnosed as obstructive sleep apnea syndrome

BACKGROUND

Narcolepsy is a chronic neurological syndrome, which is characterized by excessive sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis during the rapid eye movement period of sleep. This disease is commonly diagnosed within adulthood. However, the first symptoms often appear in childhood and/or adolescence. Pediatric cases of narcolepsy generally remain unrecognized and undiagnosed. Clinical heterogeneity, prolonged onset and diverse symptoms contribute to the delay in diagnosis and treatment in childhood.

CASE

This report describes a case of narcolepsy in an 8,5-year-old male patient who was misdiagnosed as obstructive sleep apnea syndrome and many other diagnoses at different hospitals over a period of 3 years before the correct diagnosis was made.

CONCLUSIONS

Narcolepsy in children is a rare neurological syndrome, which can occur with uncommon and atypical clinical presentations. In our case report we aimed to highlight pediatric narcolepsy, which could help to make more appropriate approaches and prevent misdiagnoses or diagnosis delay in these cases.

Dream Generation and Recall in Daytime NREM Sleep of Patients With Narcolepsy Type 1

The less rigid architecture of sleep in patients with narcolepsy type 1 (NT1) compared with healthy subjects may provide new insights into some unresolved issues of dream experience (DE), under the assumption that their DE frequencies are comparable. The multiple transition from wakefulness to REM sleep (sleep onset REM period: SOREMP) during the five trials of the Multiple Sleep Latency Test (MSLT) appears of particular interest. In MSLT studies, NT1 patients reported a DE after about 80% of SOREMP naps (as often as after nighttime REM sleep of themselves and healthy subjects), but only after about 30% of NREM naps compared to 60% of daytime and nighttime NREM sleep of healthy subjects. To estimate accurately the “real” DE frequency, we asked participants to report DE (“dream”) after each MSLT nap and, in case of failure, to specify if they were unable to retrieve any content (“white dream”) or DE did not occur (“no-dream”). The proportions of dreams, white dreams, and no dreams and the indicators of structural organization of DEs reported after NREM naps by 17 adult NT1 patients were compared with those reported by 25 subjects with subjective complaints of excessive daytime sleepiness (sc-EDS), who take multiple daytime NREM naps. Findings were consistent with the hypothesis of a failure in recall after awakening rather than in generation during sleep: white dreams were more frequent in NT1 patients than in sc-EDS subjects (42.86 vs 17.64%), while their frequency of dreams plus white dreams were similar (67.86 and 61.78%) and comparable with that of NREM-DEs in healthy subjects. The longer and more complex NREM-DEs of NT1 patients compared with sc-EDS subjects suggest that the difficulty in DE reporting depends on their negative attitude toward recall of contents less vivid and bizarre than those they usually retrieve after daytime SOREMP and nighttime REM sleep. As this attitude may be reversed by some recall training before MSLT, collecting wider amounts of DE reports after NREM naps would cast light on both the across-stage continuity in the functioning of cognitive processes underlying DE and the difference in content and structural organization of SOREM-DEs preceded by N1 or also N2 sleep.

[Psychogenically induced narcolepsy]

Based on own clinical experience in diagnostics and treatment of 4 patients, the authors describe main clinical presentations of narcolepsy. A case report of a 20-year female patient with psychogenic narcolepsy induced by a conflict in the family is described in details. According to polysomnography and Multiple Sleep Latency Test, a reduction in latency to sleep is 22 sec - 3 min 30 sec and the time of occurrence of REM sleep is 7 min 30 sec. The diagnosis is made on the basis of diagnostic criteria of narcolepsy. On average, it takes about 7-10 years to diagnose narcolepsy that reduces the quality of life of patients and leads to social and household maladaptation. Physicians should be wary of early identification of this disease for dynamic monitoring, the appointment of symptomatic therapy, prevention of anxiety and depression and the generation of behavior algorithm in the patient and his relatives in order to maximize social and household adaptation.

Narcolepsy type 1

Although being the second most common cause of disabling daytime sleepiness in the world, narcolepsy in India is seldom diagnosed. So far, only two cases had been reported. This is the case of narcolepsy in a 15-year-old female student struggling in her scholastic pursuit because of the disease.

A Pediatric Case of Narcolepsy Presenting as Syncope

Narcolepsy is a chronic genetic and sleep disorder that is caused by a protein deficiency. This may affect the patients' sleep architecture and the brain's ability to control circadian rhythms. Individuals with this condition feel rested after waking but then feel tired and sleepy as the day progresses. Typical onset is during adolescence, but there is often a significant delay in diagnosis, which may markedly hinder an individual's quality of life. This case provides an opportunity to shed light on this often underdiagnosed or misdiagnosed condition by presenting a case of a remarkable individual who has persevered to be successful with the help of a timely diagnosis and aggressive off-label therapy.

[Effects of sleep body posture on subjective sleepiness in patients with OSAHS]

Objective:To observe the effects of sleep body posture on subjective sleepiness in patients with OSAHS.Method: We assessed the sleeping body position, the sleep structure, position specific AHI and the Epworth Sleepiness Scale (ESS) in a total of 90 patients with OSAHS. The patients were grouped according to AHI: mild OSAHS (5≤AHI<15), moderate (15≤AHI<30) and severe (AHI≥30). The polysomnography data and clinical characteristics were compared between each group.Result: There was statistically significant difference in arousal index，MinSpO2，REM% and NREM% among three groups (F value was 12.10,43.67,15.81,13.17，respectively，P<0.05). Compared with supine，the severe OSAHS group had significantly bigger changes in MinSpO2， REM% and NREM%（t value was 3.02,2.41,2.90，respectively，P<0.05）. For mild-to-moderate groups，there was no correlation between the ESS and the AHI at any position（P>0.05）. For severe group，the ESS was significantly correlated with L-AHI（r=0.454，P<0.01)；the REM L-AHI and NREM L-AHI was also significantly correlated with ESS of severe group (r=0.522 and 0.425，P<0.01). Conclusion:The sleep body posture had significant effects on sleep structure and respiratory events in severe OSAHS group. The L-AHI was found to have a closer association with daytime sleepiness in severe OSAHS than other groups.

Off-label Sodium Oxybate in Childhood Narcolepsy: A Comprehensive Report

Narcolepsy is a sleep disorder that can manifest in childhood or adolescence by causing excessive sleepiness, hallucinations, sleep attacks, or cataplexy. There is often a significant delay in diagnosis with the mean time being 15 years from the onset of symptoms, which may lead to further exacerbations and a high comorbidity burden. Although narcolepsy is predominantly associated with loss of hypocretin (orexin), the role of genetics is poorly understood and, therefore, is complementary to the diagnosis but not confirmatory. We present the case of a child who was misdiagnosed as suffering from schizophrenia only to later uncover narcolepsy with cataplexy. Even though she did not meet strict criteria for narcolepsy type 1, her history and objective data were consistent enough to make an official diagnosis. In addition, her clinical response to treatment was very positive, further supporting narcolepsy as the most likely underlying condition. This presentation highlights the importance of continued education and research to reduce the risk of delay in diagnosis or misdiagnosis.

Sleepless Night and Day, the Plight of Progressive Supranuclear Palsy

Objectives

To elucidate the unique sleep and waking characteristics in progressive supranuclear palsy (PSP), a neurodegenerative disease associated with motor deficits and dementia that largely affects the brainstem and thalamic regions.

Methods

A total of 20 PSP and 16 healthy older adult controls participated in this study. The participants underwent an overnight polysomnography and multiple sleep latency test (MSLT) the following day. Prior to the MSLT last trial, they were asked to complete the Stanford Sleepiness Scale. Data were assessed for measures of latency to sleep onset, sleep duration, waking, and sleep staging during the night. Mean sleep latency, a measure of daytime sleepiness, sleep onset rapid eye movement (REM) periods, and microsleeps were studied with the MSLT. Spectral analysis of wake electroencephalogram (EEG) was performed for 30-second periods at the start of each MSLT trial.

Results

PSP took significantly longer time to fall asleep (p < .001), slept less during the night (p ≤ .001), and had more wake after sleep onset than controls (p ≤ .001). PSP had less N2 sleep (p < .05) and N3 sleep (p < .05), and REM sleep (p < .001) than controls. During the MSLT, PSP took significantly longer to fall asleep (p < .001), did not have microsleeps when they remained awake throughout the assessment periods, but were subjectively sleepier than controls (p < .05). Gamma power was increased during wake EEG in PSP (p < .01).

Conclusions

Sleep/waking regulation and REM sleep regulation are disrupted in PSP, leading to profound sleep deprivation without recuperation. Our findings suggest a diminished homeostatic sleep drive in PSP. This hyperaroused state is unique and is a severely disabling feature of PSP.

Cancer-related fatigue presenting with excessive daytime sleepiness

Cancer-related fatigue is a common symptom in cancer patients which commonly occurs in relation to sleep disturbance. We report a case of a 35-year-old breast cancer survivor, in whom polysomnography and multiple sleep latency testing were utilized to objectively quantify the contribution of excessive daytime sleepiness to the patient’s cancer-related fatigue.

A novel in-ear sensor to determine sleep latency during the Multiple Sleep Latency Test in healthy adults with and without sleep restriction

OBJECTIVES

Detecting sleep latency during the Multiple Sleep Latency Test (MSLT) using electroencephalogram (scalp-EEG) is time-consuming. The aim of this study was to evaluate the efficacy of a novel in-ear sensor (in-ear EEG) to detect the sleep latency, compared to scalp-EEG, during MSLT in healthy adults, with and without sleep restriction.

METHODS

We recruited 25 healthy adults (28.5±5.3 years) who participated in two MSLTs with simultaneous recording of scalp and in-ear EEG. Each test followed a randomly assigned sleep restriction (≤5 hours sleep) or usual night sleep (≥7 hours sleep). Reaction time and Stroop test were used to assess the functional impact of the sleep restriction. The EEGs were scored blind to the mode of measurement and study conditions, using American Academy of Sleep Medicine 2012 criteria. The Agreement between the scalp and in-ear EEG was assessed using Bland-Altman analysis.

RESULTS

Technically acceptable data were obtained from 23 adults during 69 out of 92 naps in the sleep restriction condition and 25 adults during 85 out of 100 naps in the usual night sleep. Meaningful sleep restrictions were confirmed by an increase in the reaction time (mean ± SD: 238±30 ms vs 228±27 ms; P=0.045). In the sleep restriction condition, the in-ear EEG exhibited a sensitivity of 0.93 and specificity of 0.80 for detecting sleep latency, with a substantial agreement (κ=0.71), whereas after the usual night's sleep, the in-ear EEG exhibited a sensitivity of 0.91 and specificity of 0.89, again with a substantial agreement (κ=0.79).

CONCLUSION

The in-ear sensor was able to detect reduced sleep latency following sleep restriction, which was sufficient to impair both the reaction time and cognitive function. Substantial agreement was observed between the scalp and in-ear EEG when measuring sleep latency. This new in-ear EEG technology is shown to have a significant value as a convenient measure for sleep latency.

Diagnosis and management of narcolepsy in the Indian scenario

INTRODUCTION

The diagnosis and management of narcolepsy in the Indian context needs to be revisited especially in the wake of concerns raised by sleep medicine experts that the entity could be formidably underdiagnosed, as well as undertreated in our setting.

MATERIALS AND METHODS

The history, clinical records, polysomnographic/multiple sleep latency test data, and treatment records of five hundred consecutive patients attending a dedicated sleep clinic between the years 2013 and 2016 were retrospectively analyzed. The response to treatment measures and improvement in daytime functioning were periodically assessed by personal/telephonic interview and E-mail communication.

RESULTS

Thirteen patients were diagnosed with narcolepsy based on the standard criteria of which three had cataplexy. The mean age of presentation was 23.23 years and the male:female ratio was 2.25:1. The mean duration from the onset of symptoms to diagnosis was 4.2 years. Two patients responded to nonpharmacological interventions alone, and six to modafinil, while two patients remained symptomatic and required treatment with methylphenidate. One patient was lost to follow-up, while two others are due for their first follow-up.

CONCLUSION

A refurbished outlook of the diagnostic methodology and treatment paths tailored to our clinical scenario can potentially impact the future of narcolepsy management and research in our country.

Subjective and Objective Measures of Hypersomnolence Demonstrate Divergent Associations with Depression among Participants in the Wisconsin Sleep Cohort Study

STUDY OBJECTIVES

To examine associations of depression with habitual sleep duration, daytime sleepiness, and objective sleep propensity in a nonclinical population.

METHODS

Data from adults participating in the Wisconsin Sleep Cohort Study were utilized in analyses. There were 1,287 adults (3,324 observations) who were used in the analysis of subjective hypersomnolence measures; 1,155 adults (2,981 observations) were used in the analysis of objective sleep propensity assessed by the multiple sleep latency test (MSLT). Repeated-measures logistic regression estimated associations between presence of depression (defined as modified Zung Self-Rating Depression Scale ≥ 50 or use of antidepressant medications) and three primary hypersomnolence measures: subjective excessive daytime sleepiness (Epworth Sleepiness Scale [ESS] ≥ 11), self-reported sleep duration ≥ 9 h/d, and objective sleep propensity (MSLT mean sleep latency < 8 min).

RESULTS

After adjusting for age, sex, body mass index, chronic medical conditions, sedative hypnotic medication use, caffeine, tobacco, and alcohol use, sleep disordered breathing, as well as insomnia and sleep duration when appropriate, estimated odd ratios (95% confidence interval) for depression were: 1.56 (1.31,1.86) for ESS ≥ 11; 2.01 (1.49, 2.72) for habitual sleep time ≥ 9 h; and 0.76 (0.63-0.92) for MSLT mean sleep latency < 8 min.

CONCLUSIONS

Our results demonstrate divergent associations between subjective and objective symptoms of hypersomnolence and depression, with subjective sleepiness and excessive sleep duration associated with increased odds of depression, but objective sleep propensity as measured by the MSLT associated with decreased odds of depression. Further research is indicated to explain this paradox and the impact of different hypersomnolence measures on the course of mood disorders.

COMMENTARY

A commentary on this article appears in this issue on page 467.

Sleep Perception in Obstructive Sleep Apnea: A Study Using Polysomnography and the Multiple Sleep Latency Test

Background and Purpose

Discrepancies between objectively measured sleep and subjective sleep perception in patients with insomnia have been reported. However, few studies have investigated sleep-state misperception in patients with obstructive sleep apnea (OSA). We designed this study to 1) delineate the factors that could affect this discrepancy and 2) infer an underlying mechanism in patients with OSA.

Methods

We recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography.

Results

Fifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers.

Conclusions

As an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.

Altered Sleep Stage Transitions of REM Sleep: A Novel and Stable Biomarker of Narcolepsy

OBJECTIVES

To determine the diagnostic values, longitudinal stability, and HLA association of the sleep stage transitions in narcolepsy.

METHODS

To compare the baseline differences in the sleep stage transition to REM sleep among 35 patients with type 1 narcolepsy, 39 patients with type 2 narcolepsy, 26 unaffected relatives, and 159 non-narcoleptic sleep patient controls, followed by a reassessment at a mean duration of 37.4 months.

RESULTS

The highest prevalence of altered transition from stage non-N2/N3 to stage R in multiple sleep latency test (MSLT) and nocturnal polysomnography (NPSG) was found in patients with type 1 narcolepsy (92.0% and 57.1%), followed by patients with type 2 narcolepsy (69.4% and 12.8%), unaffected relatives (46.2% and 0%), and controls (39.3% and 1.3%). Individual sleep variables had varied sensitivity and specificity in diagnosing narcolepsy. By incorporating a combination of sleep variables, the decision tree analysis improved the sensitivity to 94.3% and 82.1% and enhanced specificity to 82.4% and 83% for the diagnosis of type 1 and type 2 narcolepsy, respectively. There was a significant association of DBQ1*0602 with the altered sleep stage transition (OR = 16.0, 95% CI: 1.7-149.8, p = 0.015). The persistence of the altered sleep stage transition in both MSLT and NPSG was high for both type 1 (90.5% and 64.7%) and type 2 narcolepsy (92.3% and 100%), respectively.

CONCLUSION

Altered sleep stage transition is a significant and stable marker of narcolepsy, which suggests a vulnerable wake-sleep dysregulation trait in narcolepsy. Altered sleep stage transition has a significant diagnostic value in the differential diagnosis of hypersomnias, especially when combined with other diagnostic sleep variables in decision tree analysis.

Insomnia in shift work disorder relates to occupational and neurophysiological impairment

STUDY OBJECTIVES

To determine whether occupational and neurophysiological decrements within shift work disorder (SWD) are differentially related to its two diagnostic symptoms, insomnia and excessive sleepiness.

METHODS

Thirty-four permanent night workers participated in an overnight lab protocol including a multiple sleep latency test (MSLT) and an event-related brain potential (ERP) task testing auditory target detection (P3a and P3b). At 16:00, each subject completed an Endicott Work Productivity Scale (EWPS), two Insomnia Severity Indices (ISI-Day, ISI-Night), and an Epworth Sleepiness Scale (ESS). Subjects were grouped by ISI and ESS scores into clinical phenotypes. This study compared EWPS and ERP results between alert insomniacs ("AI," reporting insomnia without sleepiness), sleepy insomniacs ("SI," reporting both insomnia and sleepiness), and controls.

RESULTS

The AI group was most impaired on the EWPS, significantly more impaired than controls (25.8 ± 14.8 vs. 12.3 ± 9.4, p < 0.05). SI were not statistically different from controls (19.5 ± 8.7 vs. 12.3 ± 9.4, p > 0.05). Compared to controls, AI showed significantly attenuated P3a response (Fcz, Czp, Cpz, mean difference [MD] 1.62-1.77, p < 0.05) and target-detection P3b response (Fcz, Czp, Cpz, MD 1.28-1.64, p < 0.05). P3b in SI was not different from controls (p > 0.10), and P3a was only different at one electrode site (Cpz, MD 1.43, p < 0.01). Neither the MSLT nor the ESS correlated with EWPS scores or ERP (P3a/P3b) amplitudes (p > 0.10). However, the mean of the ISI measurements correlated with the EWPS (r = 0.409, p < 0.01) and the attention-to-novelty P3a (r = -0.410, p < 0.01).

CONCLUSIONS

Among shift work disorder patients, insomnia is linked to functional and cognitive impairments. Insomniacs with normal sleepiness showed more severe impairments than insomniacs who also reported excessive sleepiness.

Insomnia with physiological hyperarousal is associated with hypertension

Previous studies have suggested that insomnia with objective short sleep duration is associated with a higher risk of hypertension, and it has been speculated that the underlying mechanism is physiological hyperarousal. In this study, we tested whether insomnia with physiological hyperarousal measured by Multiple Sleep Latency Test (MSLT), a standard test of sleepiness/alertness, is associated with increased risk of hypertension. Two hundred nineteen chronic insomniacs and 96 normal sleepers were included in this study. Chronic insomnia was defined based on standard diagnostic criteria with symptoms lasting ≥6 months. All subjects underwent 1 night in laboratory polysomnography followed by a standard MSLT. We used the median mean MSLT value (ie, >14 minutes) and the 75th percentile of mean MSLT value (ie, >17 minutes) to define hyperarousal. Hypertension was defined based either on blood pressure measures or on diagnosis treatment by a physician. After controlling for age, sex, body mass index, apnea-hypopnea index, diabetes mellitus, smoking, alcohol, and caffeine use, insomnia combined with MSLT >14 minutes increased the odds of hypertension by 300% (odds ratio=3.27; 95% confidence interval=1.20-8.96), whereas insomnia combined with MSLT >17 minutes increased even further the odds of hypertension by 400% (odds ratio=4.33; 95% confidence interval=1.48-12.68) compared with normal sleepers with MSLT ≤14 minutes. Insomnia associated with physiological hyperarousal is associated with a significant risk of hypertension. Long MSLT values may be a reliable index of the physiological hyperarousal and biological severity of chronic insomnia.

Urine toxicology screen in multiple sleep latency test: the correlation of positive tetrahydrocannabinol, drug negative patients, and narcolepsy

OBJECTIVE

Drugs can influence results of multiple sleep latency tests (MSLT). We sought to identify the effect of marijuana on MSLT results in pediatric patients evaluated for excessive daytime sleepiness (EDS).

METHODS

This is a retrospective study of urine drug screens performed the morning before MSLT in 383 patients <21 years old referred for EDS. MSLT results were divided into those with (1) (-) urine drug screens, (2) urine drug screens (+) for tetrahydrocannabinol (THC) alone or THC plus other drugs, and (3) urine drug screens (+) for drugs other than THC. Groups were compared with Fisher exact tests or one-way ANOVA.

RESULTS

38 (10%) urine drug tests were (+): 14 for THC and 24 for other drugs. Forty-three percent of patients with drug screen (+) for THC had MSLT findings consistent with narcolepsy, 0% consistent with idiopathic hypersomnia, 29% other, and 29% normal. This was statistically different from those with (-) screens (24% narcolepsy, 20% idiopathic hypersomnia, 6% other, 50% normal), and those (+) for drugs other than THC (17% narcolepsy, 33% idiopathic hypersomnia, 4% other, 46% normal (p = 0.01). Six percent (6/93) of patients with MSLT findings consistent with narcolepsy were drug screen (+) for THC; 71% of patients with drug screen (+) for THC had multiple sleep onset REM periods (SOREMS). There were no (+) urine drug screens in patients <13 years old.

CONCLUSION

Many pediatric patients with (+) urine drug screens for THC met MSLT criteria for narcolepsy or had multiple SOREMs. Drug screening is important in interpreting MSLT findings for children ≥13 years.

Psychomotor vigilance task demonstrates impaired vigilance in disorders with excessive daytime sleepiness

STUDY OBJECTIVE

The Psychomotor Vigilance Task (PVT) is one of the leading assays of sustained vigilant attention in sleep research and highly sensitive to the effects of sleep loss. Even though PVT is widely used in sleep deprivation studies, little is known about PVT performance in patients suffering from sleep-wake disorders. We aimed to quantify the impact of sleep-wake disorders on PVT outcome measures and examine whether PVT can distinguish between healthy controls and patients with sleep-wake disorders and whether PVT can distinguish between three different disorders that express excessive daytime sleepiness.

METHODS

We compared PVT data of 143 patients and 67 age- and gender-matched healthy controls. Patients were diagnosed with one of the following sleep-wake disorders: narcolepsy with cataplexy (n = 20), insufficient sleep syndrome (ISS, n = 67) and hypersomnia (HS, n = 56). Several PVT outcomes were analyzed: reciprocal mean reaction time, response variability, number of lapses, number of false reaction time, slowest and fastest 10% of reaction time, and duration of lapses.

RESULTS

PVT performance was generally better in healthy controls than in patients with any of the sleep-wake disorders analyzed. Patients with narcolepsy and HS performed worse on PVT than subjects with ISS. In controls, but not in patients, older subjects had slower reactions times and higher response variability in PVT.

CONCLUSIONS

PVT performance shows different patterns in patients with different sleep-wake disorders and control subjects and may add useful information to the diagnostic work-up of sleep-wake disorders.

Challenges in diagnosing narcolepsy without cataplexy: a consensus statement

BACKGROUND

Diagnosing narcolepsy without cataplexy is often a challenge as the symptoms are nonspecific, current diagnostic tests are limited, and there are no useful biomarkers. In this report, we review the clinical and physiological aspects of narcolepsy without cataplexy, the limitations of available diagnostic procedures, and the differential diagnoses, and we propose an approach for more accurate diagnosis of narcolepsy without cataplexy.

METHODS

A group of clinician-scientists experienced in narcolepsy reviewed the literature and convened to discuss current diagnostic tools, and to map out directions for research that should lead to a better understanding and more accurate diagnosis of narcolepsy without cataplexy.

RECOMMENDATIONS

To aid in the identification of narcolepsy without cataplexy, we review key indicators of narcolepsy and present a diagnostic algorithm. A detailed clinical history is mainly helpful to rule out other possible causes of chronic sleepiness. The multiple sleep latency test remains the most important measure, and prior sleep deprivation, shift work, or circadian disorders should be excluded by actigraphy or sleep logs. A short REM sleep latency (≤ 15 minutes) on polysomnography can aid in the diagnosis of narcolepsy without cataplexy, although sensitivity is low. Finally, measurement of hypocretin levels can helpful, as levels are low to intermediate in 10% to 30% of narcolepsy without cataplexy patients.

multiple sleep latency test in patients with obstructive sleep apnea

OBJECTIVES

The aims of this study were to determine (1) the agreement in Epworth Sleepiness Scale (ESS) evaluated by patients and their close relatives (CRs), and (2) the correlation of objective sleepiness as measured by multiple sleep latency test (MSLT) with self-evaluated and close relative-evaluated ESS.

METHODS

A total of 85 consecutive patients with obstructive sleep apnea (OSA) (70 males, age 46.7 ± 12.9 years old) with an apnea-hypopnea index (AHI) > 5 events per hour (mean 38.9 ± 26.8/h) were recruited into this study. All participants underwent an overnight polysomnographic assessment (PSG), MSLT, and ESS rated by both patients and their CRs. Mean sleep latency < 8 min on MSLT was considered objective daytime sleepiness.

RESULTS

Self-evaluated global ESS score (ESSG) was closely correlated with evaluation by CRs (r = 0.79, p < 0.001); the mean ESSG score evaluated by patients did not significantly differ from that evaluated by CRs (p > 0.05). However, Bland- Altman plot showed individual differences between self-evaluated and CR-evaluated ESS scores, with a 95%CI of -9.3 to 7.0. The mean sleep latency on MSLT was significantly associated with CR-evaluated ESSG (r = -0.23, p < 0.05); significance of association with self-evaluated ESSG was marginal (r = -0.21, p = 0.05).

CONCLUSIONS

CR-evaluated ESS has a good correlation but also significant individual disagreement with self-evaluated ESS in Chinese patients with OSA. CR-evaluated ESS performs as well as, if not better than, self-evaluated ESS in this population when referring to MSLT.

Sertraline and rapid eye movement sleep without atonia: an 8-week, open-label study of depressed patients

Previous studies have reported that selective serotonin reuptake inhibitors (SSRIs) may induce or exacerbate rapid eye movement (REM) sleep without atonia (RSWA) and increase the risk of developing REM sleep behavior disorder (RBD). However, most of these studies are retrospective and cross-sectional and employed small sample sizes and a mixture of SSRIs. In this 8-week open-label trial of sertraline in depressed patients (n = 31), depressed patients were administered 50mg sertraline at 8 am on the 1st day and subsequently titrated up to a maximum of 200mg/day. All patients underwent repeated video-polysomnography (vPSG) (baseline, 1st day, 14th day, 28th day, and 56th day). Both tonic (submental) and phasic (submental and anterior tibialis) RSWA events were visually counted. Tonic RSWA increased from 3.2 ± 1.8% at baseline to 5.1 ± 2.3% on the 1st day and 10.4 ± 2.7% on the 14th day; after that, measurements were stable until the 56th day. A similar profile was observed for phasic RSWA. The increases in tonic RSWA (r = 0.56, P = 0.004) and phasic RSWA (submental: r = -0.51, P = 0.02; anterior tibialis: r = 0.41, P = 0.04) were correlated with the degree of the prolonging of REM latency. All of RSWAs were not correlated with patients' demographic and clinical characteristics. Sertraline may induce or exacerbate RSWA. In contrast to idiopathic RBD, sertraline-related RSWA had the specific characteristics of being correlated with the degree of the prolonging of REM latency and no predominance of male sex and elder age, suggesting different pathophysiological mechanisms. The antidepressant-related RSWA should be a potential public health problem in the depressed patients.

Undiagnosed and comorbid disorders in patients with presumed chronic fatigue syndrome

OBJECTIVE

To assess undiagnosed and comorbid disorders in patients referred to a tertiary care center with a presumed diagnosis of chronic fatigue syndrome (CFS).

METHODS

Patients referred for chronic unexplained fatigue entered an integrated diagnostic pathway, including internal medicine assessment, psychodiagnostic screening, physiotherapeutic assessment and polysomnography+multiple sleep latency testing. Final diagnosis resulted from a multidisciplinary team discussion. Fukuda criteria were used for the diagnosis of CFS, DSM-IV-TR criteria for psychiatric disorders, ICSD-2 criteria for sleep disorders.

RESULTS

Out of 377 patients referred, 279 (74.0%) were included in the study [84.9% female; mean age 38.8years (SD 10.3)]. A diagnosis of unequivocal CFS was made in 23.3%. In 21.1%, CFS was associated with a sleep disorder and/or psychiatric disorder, not invalidating the diagnosis of CFS. A predominant sleep disorder was found in 9.7%, 19.0% had a psychiatric disorder and 20.8% a combination of both. Only 2.2% was diagnosed with a classical internal disease. In the total sample, a sleep disorder was found in 49.8%, especially obstructive sleep apnea syndrome, followed by psychophysiologic insomnia and periodic limb movement disorder. A psychiatric disorder was diagnosed in 45.2%; mostly mood and anxiety disorder.

CONCLUSIONS

A multidisciplinary approach to presumed CFS yields unequivocal CFS in only a minority of patients, and reveals a broad spectrum of exclusionary or comorbid conditions within the domains of sleep medicine and psychiatry. These findings favor a systematic diagnostic approach to CFS, suitable to identify a wide range of diagnostic categories that may be subject to dedicated care.

Comparison of Polysomnography and Multiple Sleep Latency Test Findings in Subjects with Narcolepsy and İdiopathic Hypersomnia

INTRODUCTION

Both narcolepsy and idiopathic hypersomnia are the main causes of excessive daytime sleepiness. In this study, we aimed to compare polysomnography (PSG) and multiple sleep latency test (MSLT) findings in narcolepsy and idiopathic hypersomnia patients.

METHODS

The files of patients with narcolepsy and hypersomnia who were admitted between 1995 and 2009 were reviewed. We evaluated data from 94 patients with narcolepsy with cataplexy, 49 with narcolepsy without cataplexy and 140 patients with idiopathic hypersomnia.

RESULT

Sleep latency and REM latency were longer in idiopathic hypersomnia group than in narcolepsy with and without cataplexy group. Mean sleep latency in MSLT was the shortest in narcolepsy with cataplexy group. There was no difference in sleep efficiency, percentage of sleep stage and number of awakenings in PSG between three groups.

CONCLUSION

The findings of the study indicated that narcolepsy patients differ from idiopathic hypersomnia patients in terms of sleep latency and REM latency in PSG.

Biphasic effects of alcohol as a function of circadian phase

STUDY OBJECTIVES

To assess how alcohol affects multiple sleep latency tests (MSLT) and subjective measures of stimulation/sedation when alcohol is given at different circadian phases.

PARTICIPANTS

Twenty-seven healthy young adults (age 21-26 yr) were studied.

DESIGN

Double-blind placebo and alcohol (vodka tonic targeting 0.05 g% concentration) beverages were each administered three times during the 20-h forced desynchrony protocol. Sleep latency tests and Biphasic Effects of Alcohol Scale (BAES) were administered on each forced desynchrony day. The outcome variables for this study include sleep onset latency (SOL) and stimulation and sedation value (from the BAES). Each outcome variable was associated with the ascending or descending limb of the breath alcohol concentration (BrAC) curve and assigned a circadian phase within a 90° bin.

MEASUREMENTS AND RESULTS

BrAC confirmed targeted maximal levels. Only outcome variables associated with the ascending and descending limb of the alcohol curve were analyzed for this article. Alcohol administered at a circadian time associated with greatest sleepiness showed longer SOL compared with placebo when measured on the ascending limb of the BrAC curve. We also found longer SOL with alcohol on the ascending limb of the BrAC curve in a circadian bin that favors greatest alertness. We observed shorter SOLs on the descending limb of the BrAC curve, but with no circadian phase interaction. The subjective data were partially consistent with the objective data.

CONCLUSIONS

The physiologic findings in this study support the biphasic stimulating and sedating properties of alcohol, but limit the effect to specific circadian times.

Reliability of a single objective measure in assessing sleepiness

STUDY OBJECTIVES

To evaluate reliability of single objective tests in assessing sleepiness.

DESIGN

Subjects who completed polysomnography underwent a 4-nap multiple sleep latency test (MSLT) the following day. Prior to each nap opportunity on MSLT, subjects performed the psychomotor vigilance test (PVT) and divided attention driving task (DADT). Results of single versus multiple test administrations were compared using the intraclass correlation coefficient (ICC) and adjusted for test administration order effects to explore time of day effects. Measures were explored as continuous and binary (i.e., impaired or not impaired).

SETTING

Community-based sample evaluated at a tertiary, university-based sleep center.

PARTICIPANTS

372 adult commercial vehicle operators oversampled for increased obstructive sleep apnea risk.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

AS CONTINUOUS MEASURES, ICC WERE AS FOLLOWS: MSLT 0.45, PVT median response time 0.69, PVT number of lapses 0.51, 10-min DADT tracking error 0.87, 20-min DADT tracking error 0.90. Based on binary outcomes, ICC were: MSLT 0.63, PVT number of lapses 0.85, 10-min DADT 0.95, 20-min DADT 0.96. Statistically significant time of day effects were seen in both the MSLT and PVT but not the DADT. Correlation between ESS and different objective tests was strongest for MSLT, range [-0.270 to -0.195] and persisted across all time points.

CONCLUSIONS

Single DADT and PVT administrations are reliable measures of sleepiness. A single MSLT administration can reasonably discriminate individuals with MSL < 8 minutes. These results support the use of a single administration of some objective tests of sleepiness when performed under controlled conditions in routine clinical care.

Antiparkinsonian drug-induced sleepiness: a double-blind placebo-controlled study of L-dopa, bromocriptine and pramipexole in healthy subjects

AIMS

To assess the sleepiness induced by pramipexole, a D2/D3-dopamine receptor agonist commonly used in Parkinson's disease and restless legs syndrome, without the problem of the confounding factors related to the disease.

METHODS

Placebo, bromocriptine (2.5 mg), L-dopa (100 mg) and pramipexole (0.5 mg) were administered in a single oral dose on four separate days, with at least a 2-week wash-out period in a randomized cross-over design. Induced somnolence was assessed using Multiple Sleep Latency Test (MSLT) and subjective scaling of vigilance. Twelve male subjects (26.3 +/- 5.5 years old) without anxiety, mood, sleep or sedation disorders were enrolled.

RESULTS

Pramipexole significantly reduced mean sleep latency compared with placebo 3 h 30 min [-6.1 min (-9.8, -2.4), P = 0.002] and 5 h 30 min [-5.6 min (-7.7, -3.5), P = 0.003] after administration. In addition, the total duration of sleep during the tests was higher with pramipexole than with placebo [+6.0 min (2.3, 9.7), P < 0.001]. These differences were not observed with L-dopa and bromocriptine in comparison with placebo. The induced sleepiness was not associated with an increase in subjective somnolence scaling, indicating that this adverse event may occur without prior warning.

CONCLUSIONS

These results show that a single oral dose of pramipexole induces sleepiness as assessed by MSLT in healthy young subjects, independent of disease-related sleep dysfunction.

Subjective sleepiness and polysomnographic correlates in children scheduled for adenotonsillectomy vs other surgical care

STUDY OBJECTIVE

To compare a validated subjective measure of childhood sleepiness to an objective determination, assess the frequency of problematic sleepiness among children with suspected sleep-disordered breathing (SDB), and examine what standard or investigational polysomnographic measures of SDB predict subjective sleepiness.

DESIGN

Prospective, cross-sectional.

SETTING

University-based sleep disorders laboratory.

PARTICIPANTS

Washtenaw County Adenotonsillectomy Cohort.

INTERVENTION

Polysomnography followed by Multiple Sleep Latency Tests (MSLTs) in 103 children aged 5 to 12 years old: 77 were scheduled for clinically indicated adenotonsillectomy, usually for suspected SDB, and 26 for unrelated surgical care. Parents completed the previously validated, 4-item Pediatric Sleep Questionnaire-Sleepiness Subscale (PSQ-SS).

RESULTS

Thirty-three (43%) of the children scheduled for adenotonsillectomy had high PSQ-SS scores, in comparison with only 3 (12%) of the controls (p = .004). The PSQ-SS scores correlated inversely with mean sleep latencies on the MSLTs (rho = -0.23, p = .006). The obstructive apnea index, apnea-hypopnea index, and respiratory disturbance index (which included respiratory event-related arousals identified by esophageal pressure monitoring) each correlated similarly with PSQ-SS scores, as did investigational quantification of esophageal pressures and respiratory cycle-related electroencephalographic changes (each rho approximately 0.30, p < .02). A stepwise regression identified sigma-frequency respiratory cycle-related electroencephalographic changes as the strongest independent predictor of subjective sleepiness among all subjects and particularly among those without obstructive sleep apnea.

CONCLUSIONS

Sleepiness is a frequent problem among children with suspected SDB. Subjective sleepiness (PSQ-SS) reflects MSLT results to a limited extent, as in adults. Standard polysomnographic measures of SDB predict subjective sleepiness, but respiratory cycle-related electroencephalographic changes may offer additional clinical utility.

Relative efficacy of drugs for the treatment of sleepiness in narcolepsy

A survey was conducted on 10 polysomnographic studies on the pharmacologic treatment of the sleepiness of narcolepsy. Three studies employed the MSLT and 7 employed the MWT as their polygraphic measure of sleep tendency. Statistically and clinically significant therapeutic changes were apparent for pemoline, modafinil, dextroamphetamine and methylphenidate. Codeine, ritanserin and protriptyline did show statistically significant effects. The common feature among the drugs that did produce clinically significant improvements seems to be facilitatory action on central catecholaminergic transmission. Within this group of drugs, only methylphenidate and dextroamphetamine brought MWT sleep latencies to approximately 70% of normal levels.