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Mayo Clin Proc 2021 05 9;96(5):1288-1301. Epub 2021 Apr 9.

Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN; Center for Sleep Medicine, Mayo Clinic, Rochester, MN. Electronic address:

Excessive daytime sleepiness (EDS) is a highly prevalent condition that is associated with significant morbidity. The causes of EDS are varied, and include inadequate sleep, sleep disordered breathing, circadian rhythm sleep-wake disorders, and central disorders of hypersomnolence (narcolepsy, idiopathic hypersomnia, and Kleine-Levin syndrome). Additionally, EDS could represent a symptom of an underlying medical or psychiatric disorder. Read More

J Sleep Res 2021 Apr 4:e13296. Epub 2021 Apr 4.

Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland.

Narcolepsy type 1 (NT1) is a disorder with well-established markers and a suspected autoimmune aetiology. Conversely, the narcoleptic borderland (NBL) disorders, including narcolepsy type 2, idiopathic hypersomnia, insufficient sleep syndrome and hypersomnia associated with a psychiatric disorder, lack well-defined markers and remain controversial in terms of aetiology, diagnosis and management. The Swiss Primary Hypersomnolence and Narcolepsy Cohort Study (SPHYNCS) is a comprehensive multicentre cohort study, which will investigate the clinical picture, pathophysiology and long-term course of NT1 and the NBL. Read More

Front Psychol 2021 11;12:639198. Epub 2021 Feb 11.

Norwegian Competence Center for Sleep Disorders, Haukeland University Hospital, Bergen, Norway.

Patients with insomnia complain of problems with sleep onset or sleep maintenance or early morning awakenings, or a combination of these, despite adequate opportunity and circumstances for sleep. In addition, to fulfill the diagnostic criteria for insomnia the complaints need to be associated with negative daytime consequences. For chronic insomnia, the symptoms are required to be present at least 3 days per week for a duration of at least 3 months. Read More

Sleep Med 2021 May 10;81:62-68. Epub 2021 Feb 10.

Department of Developmental and Social Psychology, Sapienza University of Rome, Italy.

Objectives: The aim of the present study is to assess the psychometric properties of the Sleep Disturbance Scale for Children (SDSC) in an Italian population of infants and toddlers.

Methods: The SDSC was distributed to the primary caregivers of infants aged 6-36 months recruited via nurseries in the urban area of Rome. Reliability analysis for evaluating internal consistency and item-total correlation coefficients, and factor analysis were performed. Read More

Sleep Med 2021 Apr 20;80:315-321. Epub 2021 Jan 20.

Medical Affairs Headquarters, Alfresa Pharma Corporation, 2-2-9 Koku-machi, Chuo-ku, Osaka, 540-8575, Japan.

Background: Few treatments are available for patients with idiopathic hypersomnia (IH). Modafinil, an established treatment for narcolepsy, was tested for efficacy and safety in Japanese patients with IH without long sleep time.

Methods: This multicenter, randomized, double-blind, placebo-controlled, parallel-group comparison study was conducted at 20 institutions in Japan. Read More

Am J Med Genet A 2021 04 20;185(4):1120-1130. Epub 2021 Jan 20.

Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.

The Per family of genes functions as a primary circadian rhythm maintenance in the brain. Mutations in PER2 are associated with familial advanced sleep-phase syndrome 1 (FASPS1), and recently suggested in delayed sleep phase syndrome and idiopathic hypersomnia. The detection of PER2 variants in individuals with autism spectrum disorder (ASD) and without reported sleep disorders, has suggested a role of circadian-relevant genes in the pathophysiology of ASD. Read More

PLoS One 2020 3;15(12):e0243366. Epub 2020 Dec 3.

Ezintsha, A Sub-Division of Wits Reproductive Health and HIV Institute, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.

Background: In South Africa, the trucking industry employs over 70,000 people and the prevalence of chronic pain in this occupational group was reported at 10%. We investigated factors associated with chronic pain in truck drivers including mental health, physical activity, and sleep, as no study has done so.

Methods: Southern African male, long-distance truck drivers were recruited at truck stops in Gauteng and Free State Provinces, South Africa (n = 614). Read More

Cochrane Database Syst Rev 2020 11 15;11:CD009178. Epub 2020 Nov 15.

Department of Psychiatry, Oxford University, Oxford, UK.

Background: Sleep disturbances, including reduced nocturnal sleep time, sleep fragmentation, nocturnal wandering, and daytime sleepiness are common clinical problems in dementia, and are associated with significant carer distress, increased healthcare costs, and institutionalisation. Although non-drug interventions are recommended as the first-line approach to managing these problems, drug treatment is often sought and used. However, there is significant uncertainty about the efficacy and adverse effects of the various hypnotic drugs in this clinically vulnerable population. Read More

Sleep 2021 03;44(3)

Department of Neurology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic.

Study Objectives: Evaluate efficacy and safety of lower-sodium oxybate (LXB), a novel oxybate medication with 92% less sodium than sodium oxybate (SXB).

Methods: Adults aged 18-70 years with narcolepsy with cataplexy were eligible. The study included a ≤30-day screening period; a 12-week, open-label, optimized treatment and titration period to transition to LXB from previous medications for the treatment of cataplexy; a 2-week stable-dose period (SDP); a 2-week, double-blind, randomized withdrawal period (DBRWP); and a 2-week safety follow-up. Read More

Cochrane Database Syst Rev 2020 11 3;11:CD013449. Epub 2020 Nov 3.

Bilbao, Spain.

Background: Obstructive sleep apnoea (OSA) is a syndrome characterised by episodes of apnoea (complete cessation of breathing) or hypopnoea (insufficient breathing) during sleep. Classical symptoms of the disease - such as snoring, unsatisfactory rest and daytime sleepiness - are experienced mainly by men; women report more unspecific symptoms such as low energy or fatigue, tiredness, initial insomnia and morning headaches. OSA is associated with an increased risk of occupational injuries, metabolic diseases, cardiovascular diseases, mortality, and being involved in traffic accidents. Read More

J Clin Sleep Med 2020 08;16(8):1255-1263

University of Pennsylvania, Philadelphia, Pennsylvania.

Study Objectives: The primary objective was to describe trends in the 2-year limited duration prevalence of narcolepsy from 2013-2016 in a large insured population with claims activity. Secondary objectives were to assess the prevalence of other sleep disorders and the frequency of diagnostic sleep testing.

Methods: Nationwide medical/prescription claims (Symphony Health) were analyzed to estimate the annual prevalence per 100,000 persons of narcolepsy and other sleep disorders (obstructive sleep apnea, idiopathic hypersomnia, rapid eye movement sleep behavior disorder, periodic limb movement disorder) and the frequency of diagnostic sleep testing. Read More

Transl Psychiatry 2020 08 17;10(1):284. Epub 2020 Aug 17.

Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan.

Attention deficit hyperactive disorder (ADHD) is a highly heritable neurodevelopmental disorder, and excessive daytime sleepiness is frequently observed in ADHD patients. Excessive daytime sleepiness is also a core symptom of narcolepsy and essential hypersomnia (EHS), which are also heritable conditions. Psychostimulants are effective for the symptomatic control of ADHD (primary recommended intervention) and the two sleep disorders (frequent off-label use). Read More

Epilepsy Behav 2021 01 8;114(Pt A):107272. Epub 2020 Jul 8.

Center for Health Equity and Quality Research (CHEQR), University of Florida College of Medicine, Jacksonville, FL, 580 W. 8th St, Tower 1, 9th floor, UF Department of Neurology, Jacksonville, FL 32209, United States of America.

Purpose: Evaluation of daytime sleepiness in the clinical sleep practice is commonly performed by administering the Epworth Sleepiness Scale (ESS). Our study investigates gender differences of ESS responses in patients (PTs) with a primary complaint of nighttime sleep disruption as they relate to ESS responses obtained from PTs' spouses (Ss).

Methods: One hundred and sixty-four patient-spouse (PT-S) pairs were recruited for the study and asked to independently complete ESS questionnaires consisting of 8 sleepiness scenarios (Q1-Q8). Read More

Semergen 2020 Jul - Aug;46(5):355-362. Epub 2020 Jul 6.

Medicina Familiar y Comunitaria, Centro de Salud Periurbana Norte, Villares de la Reina, Salamanca, España; Grupo de Trabajo de Neurología SEMERGEN, España.

Myotonic dystrophy type 1 (DM1) or Steinert's disease (CIE-9-C: 359.21; CIE-10-ES: G71.11, ORPHA: 273) is a rare autosomal dominant inherited myopathy with almost complete penetrance and multisystemic consequences (neurological, cardiological, respiratory, endocrinological, and gastrointestinal). Read More

Ann Clin Transl Neurol 2020 06 20;7(6):924-931. Epub 2020 May 20.

Sleep-Wake Disorders Unit, Department of Neurology, Gui-de-Chauliac Hospital, CHU Montpellier, Montpellier, France.

Objectives: To investigate whether cerebrospinal fluid (CSF) and serum ferritin levels differ between patients with narcolepsy type 1 (NT1) comorbid with restless legs syndrome (RLS) or periodic leg movements during sleep (PLMS), and patients with NT1 or controls without comorbid RLS or PLMS.

Methods: Sixty-six drug-free patients with NT1 (44 males, age 38.5 years [14-81]) were enrolled, including 20 with RLS, 18 with PLMS index ≥15/h (six with both RLS and PLMS). Read More

BMC Neurol 2020 May 11;20(1):176. Epub 2020 May 11.

IRCCS Istituto delle Scienze Neurologiche di Bologna, Via Altura 3, Bologna, Italy.

Background: Narcolepsy is a rare chronic sleep disorder that typically begins in youth. Excessive daytime sleepiness is the main disabling symptom, but the disease is often associated with severe endocrine-metabolic and psychosocial issues, worsened by a long diagnostic delay, requiring a multidisciplinary approach. The scarcity of reference Sleep Centres forces the patient and family to travel for seeking medical consultations, increasing the economic and psychosocial burden of the disease. Read More

Sleep Med Clin 2020 Jun;15(2):195-203

Department of Neurology, Center for Sleep Medicine, Weill Cornell Medical College of Cornell University, 425 East 61st Street, 5th Floor, New York, NY 10065, USA. Electronic address:

Unlike other reviews written on this topic, the focus of this article is primarily on nonpharmacologic treatments for daytime sleepiness that is not secondary to other medical or psychological conditions. To provide an appropriate background on primary excessive daytime sleepiness, what is considered optimal sleep in terms of sleep duration, sleep insufficiency, and sleep need is discussed in detail. This discussion is followed by an examination of the behavioral strategy of banking sleep. Read More

J Drug Assess 2020 4;9(1):82-86. Epub 2020 Apr 4.

Chronic Respiratory Diseases Research Center (CRDRC), National Research Institute of Tuberculosis and Lung Diseases (NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

In critically ill patients, sleep is generally interrupted. Some factors that lead to such sleep interruption include the intensive care unit (ICU) circumstance, primary medical disease itself, mental stress, and impacts of many drugs and other managements utilized to treat ICU patients. Another illness that may cause profound daytime somnolence is narcolepsy. Read More

Front Neurol 2020 8;11:209. Epub 2020 Apr 8.

Department of Neurology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.

Previous studies have indicated that non-motor symptoms are primary problems in focal dystonia, but limited data are available about non-motor problems and their correlation with motor severity in generalized dystonia (GD). In the present study, we performed a case-control study and enrolled isolated inherited or idiopathic GD patients and age- and sex-matched healthy controls (HC). Clinical characteristics, motor symptoms, non-motor problems, including psychiatric co-morbidity, sleep problems, fatigue, and quality of life (QoL) were assessed in both groups using various rating scales and assessments. Read More

Cochrane Database Syst Rev 2020 04 7;4:CD007736. Epub 2020 Apr 7.

Royal Papworth Hospital, Respiratory Support and Sleep Centre, Papworth Everard, Cambridge, UK, CB23 3RE.

Background: Although highly effective in the treatment of obstructive sleep apnoea (OSA), continuous positive airway pressure (CPAP) is not universally accepted by users. Educational, supportive and behavioural interventions may help people with OSA initiate and maintain regular and continued use of CPAP.

Objectives: To assess the effectiveness of educational, supportive, behavioural, or mixed (combination of two or more intervention types) strategies that aim to encourage adults who have been prescribed CPAP to use their devices. Read More

Muscle Nerve 2020 09 10;62(3):309-320. Epub 2020 Apr 10.

Department of Molecular Genetics & Microbiology, Center for NeuroGenetics, UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida.

Myotonic dystrophies (DM), the most common muscular dystrophies, are known to have significant sleep disturbances. We analyzed the literature on sleep and excessive daytime sleepiness (EDS) in DM over the past 30 years. In this review we provide a brief overview of sleep, sleep disorders, and methods of assessment. Read More

Sleep Med 2020 06 18;70:33-42. Epub 2020 Feb 18.

Unité du Sommeil, Centre National de Référence pour la Narcolepsie, CHU Montpellier, Hôpital Gui-de-Chauliac, Service de Neurologie, Montpellier, France; INSERM, U1061, Neuropsychiatry, Montpellier, France; University Montpellier, Montpellier, France. Electronic address:

Objective: Obstructive sleep apnea (OSA) is a high prevalent disorder with severe consequences including sleepiness, metabolic, and cardiovascular disorders. The aim of this study was to assess the effect of an individualized exercise-training (IET) program with educational sessions vs educational sessions alone on severity markers of OSA over an eight-week duration.

Methods: This was a randomised, controlled, parallel-design study. Read More

Sleep Med 2020 07 19;71:113-121. Epub 2020 Feb 19.

Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria; Centre for Cognitive Neurosciences Salzburg, Salzburg, Austria; University for Medical Informatics and Health Technology, UMIT, Hall in Tirol, Austria.

In this review, we aimed at identifying the studies that have employed repetitive transcranial magnetic stimulation (rTMS) in patients with sleep disorders. Low-frequency (LF) rTMS stimulating the right dorsolateral prefrontal cortex (DLPFC) or the posterior parietal cortex (PPC) was found to be effective to reduce cortical hyperexcitability and improve the sleep quality in subjects with chronic primary insomnia (PI). Both high-frequency (HF) and LF rTMS applied over the primary motor cortex or the supplementary motor cortex seem to have transient beneficial effects in patients with restless legs syndrome (RLS). Read More

Neuroscientist 2020 08 28;26(4):310-327. Epub 2020 Feb 28.

Brain and Mind Institute, Western University, London, Ontario, Canada.

Advances in neuroimaging open up the possibility for new powerful tools to be developed that potentially can be applied to clinical populations to improve the diagnosis of neurological disorders, including sleep disorders. At present, the diagnosis of narcolepsy and primary hypersomnias is largely limited to subjective assessments and objective measurements of behavior and sleep physiology. In this review, we focus on recent neuroimaging findings that provide insight into the neural basis of narcolepsy and the primary hypersomnias Kleine-Levin syndrome and idiopathic hypersomnia. Read More

J Sleep Res 2020 10 28;29(5):e13019. Epub 2020 Feb 28.

Department of Respiratory and Sleep Medicine, Liverpool Hospital, Sydney, NSW, Australia.

The Epworth Sleepiness Scale is used frequently to measure excessive daytime sleepiness in research and clinical settings, although there is limited evidence on test-retest reliability, particularly among sleep clinic populations. The objective of this study was to evaluate the reliability of this instrument among adult patients recruited from a public hospital sleep clinic in Sydney, Australia. English-speaking participants self-completed the Epworth Sleepiness Scale on two occasions, at the specialist clinic visit and on the night of diagnostic polysomnography. Read More

Eur Psychiatry 2020 02 12;63(1):e12. Epub 2020 Feb 12.

Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain.

Background: Distinguishing prodromes of bipolar disorder (BD) specific to children/adolescents, adults, and elderly patients is essential. The primary objective of this systematic review was to determine initial and relapse prodromes identifying adult patients with BD.

Methods: PubMed, PsycINFO, and Web of Science databases were searched using a predetermined strategy. Read More

Sleep Med 2020 05 10;69:8-13. Epub 2020 Jan 10.

Faculty of Medicine, University of Iceland, Reykjavik, Iceland.

Study Objectives: To analyze the association between sleep-related symptoms and sleep length in parents and their children in relation to other risk factors in both generations.

Method: The participants were parents (n = 5,855, age 54.3 ± 6. Read More

Am J Kidney Dis 2020 05 23;75(5):782-792. Epub 2020 Jan 23.

Division of Sleep Medicine, Department of Medicine at the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA.

Daytime sleepiness, also known as hypersomnolence, is common among patients receiving maintenance dialysis and following successful kidney transplantation. Sleepiness may be secondary to medical comorbid conditions, medication side effect, insufficient sleep syndrome, and sleep-disordered breathing or the result of a primary central disorder of hypersomnolence, such as narcolepsy. Unrecognized and untreated sleep disorders are associated with substantial morbidity and mortality among patients with end-stage kidney disease. Read More

Sleep Med 2020 03 4;67:66-70. Epub 2019 Dec 4.

University of Wisconsin-Madison, Department of Population Health Sciences, Madison, WI, USA.

Background: Excessive daytime sleepiness plays an important role in the presentation and course of mood disorders. Standard objective measures of daytime sleep propensity are of little to no value in depressive illness. This study examined the psychomotor vigilance task (PVT), an objective measure of neurobehavioral alertness, and its cross-sectional and longitudinal associations with depressive symptomatology in the Wisconsin Sleep Cohort Study. Read More