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Dhafar HO, BaHammam AS. Body Weight and Metabolic Rate Changes in Narcolepsy: Current Knowledge and Future Directions. Metabolites 2022; 12:1120. [PMID: 36422261 PMCID: PMC9693066 DOI: 10.3390/metabo12111120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 08/26/2023] Open
Abstract
Narcolepsy is a known auto-immune disease that presents mainly in the teenage years with irresistible sleep attacks. Patients with narcolepsy, especially NT1, have been found to have a high prevalence of obesity and other metabolic derangements. This narrative review aimed to address the relationship between narcolepsy and changes in weight and metabolic rate, and discuss potential mechanisms for weight gain and metabolic changes and future research agendas on this topic. This article will provide a balanced, up-to-date critical review of the current literature, and delineate areas for future research, in order to understand the pathophysiological metabolic changes in narcolepsy. Articles using predefined keywords were searched for in PubMed and Google Scholar databases, with predefined inclusion and exclusion criteria. Compared to controls, patients with narcolepsy are more likely to be obese and have higher BMIs and waist circumferences. According to recent research, weight gain in narcolepsy patients may be higher during the disease's outset. The precise mechanisms causing this weight gain remains unknown. The available information, albeit limited, does not support differences in basal or resting metabolic rates between patients with narcolepsy and controls, other than during the time of disease onset. The evidence supporting the role of orexin in weight gain in humans with narcolepsy is still controversial, in the literature. Furthermore, the available data did not show any appreciable alterations in the levels of CSF melanin-concentrating hormone, plasma and CSF leptin, or serum growth hormone, in relation to weight gain. Other mechanisms have been proposed, including a reduction in sympathetic tone, hormonal changes, changes in eating behavior and physical activity, and genetic predisposition. The association between increased body mass index and narcolepsy is well-recognized; however, the relationship between narcolepsy and other metabolic measures, such as body fat/muscle distribution and metabolic rate independent of BMI, is not well documented, and the available evidence is inconsistent. Future longitudinal studies with larger sample sizes are needed to assess BMR in patients with narcolepsy under a standard protocol at the outset of narcolepsy, with regular follow-up.
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Affiliation(s)
- Hamza O. Dhafar
- The University Sleep Disorders Center, Department of Medicine, College of Medicine, King Saud University, Riyadh 11451, Saudi Arabia
- Department of Family Medicine, Prince Mansour Military Hospital, Taif 26526, Saudi Arabia
| | - Ahmed S. BaHammam
- The University Sleep Disorders Center, Department of Medicine, College of Medicine, King Saud University, Riyadh 11451, Saudi Arabia
- The Strategic Technologies Program of the National Plan for Sciences and Technology and Innovation in the Kingdom of Saudi Arabia, P.O. Box 2454, Riyadh 11324, Saudi Arabia
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2
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Honda M, Shigematsu Y, Shimada M, Honda Y, Tokunaga K, Miyagawa T. Low carnitine palmitoyltransferase 1 activity is a risk factor for narcolepsy type 1 and other hypersomnia. Sleep 2022; 45:6639424. [DOI: 10.1093/sleep/zsac160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 06/06/2022] [Indexed: 12/13/2022] Open
Abstract
Abstract
Study Objectives
Narcolepsy type 1 (NT1) is associated with metabolic abnormalities but their etiology remains largely unknown. The gene for carnitine palmitoyltransferase 1B (CPT1B) and abnormally low serum acylcarnitine levels have been linked to NT1. To elucidate the details of altered fatty acid metabolism, we determined levels of individual acylcarnitines and evaluated CPT1 activity in patients with NT1 and other hypersomnia.
Methods
Blood samples from 57 NT1, 51 other hypersomnia patients, and 61 healthy controls were analyzed. The levels of 25 major individual acylcarnitines were determined and the C0/(t[C16] + t[C18]) ratio was used as a CPT1 activity marker. We further performed transcriptome analysis using independent blood samples from 42 NT1 and 42 healthy controls to study the relevance of fatty acid metabolism. NT1-specific changes in CPT1 activity and in expression of related genes were investigated.
Results
CPT1 activity was lower in patients with NT1 (p = 0.00064) and other hypersomnia (p = 0.0014) than in controls. Regression analysis revealed that CPT1 activity was an independent risk factor for NT1 (OR: 1.68; p = 0.0031) and for other hypersomnia (OR: 1.64; p = 0.0042). There was a significant interaction between obesity (BMI <25, ≥25) and the SNP rs5770917 status such that nonobese NT1 patients without risk allele had better CPT1 activity (p = 0.0089). The expression levels of carnitine-acylcarnitine translocase (CACT) and CPT2 in carnitine shuttle were lower in NT1 (p = 0.000051 and p = 0.00014, respectively).
Conclusions
These results provide evidences that abnormal fatty acid metabolism is involved in the pathophysiology of NT1 and other hypersomnia.
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Affiliation(s)
- Makoto Honda
- Sleep Disorders Project, Department of Psychiatry and Behavioral Sciences, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
- Japan Somnology Center and Seiwa Hospital, Institute of Neuropsychiatry , Tokyo , Japan
| | - Yosuke Shigematsu
- Department of Health Science, Faculty of Medical Sciences, University of Fukui , Fukui , Japan
| | - Mihoko Shimada
- Sleep Disorders Project, Department of Psychiatry and Behavioral Sciences, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo , Tokyo , Japan
- Genome Medical Science Project (Toyama), National Center for Global Health and Medicine , Tokyo , Japan
| | - Yoshiko Honda
- Sleep Disorders Project, Department of Psychiatry and Behavioral Sciences, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
| | - Katsushi Tokunaga
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo , Tokyo , Japan
- Genome Medical Science Project (Toyama), National Center for Global Health and Medicine , Tokyo , Japan
| | - Taku Miyagawa
- Sleep Disorders Project, Department of Psychiatry and Behavioral Sciences, Tokyo Metropolitan Institute of Medical Science , Tokyo , Japan
- Department of Human Genetics, Graduate School of Medicine, The University of Tokyo , Tokyo , Japan
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3
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Mohammadi S, Moosaie F, Saghazadeh A, Mahmoudi M, Rezaei N. Metabolic profile in patients with narcolepsy: a systematic review and meta-analysis. Sleep Med 2021; 81:268-284. [PMID: 33740593 DOI: 10.1016/j.sleep.2021.02.040] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/10/2021] [Accepted: 02/16/2021] [Indexed: 11/25/2022]
Abstract
Narcolepsy, a sleep disorder characterized by loss of hypocretin neurons, has been associated with metabolic disturbances. Although the metabolic alterations in narcolepsy patients are widely investigated in the literature, the results are controversial. We performed a systematic search of literature to identify metabolic profiling studies in narcolepsy patients. A total of 48 studies were included in the meta-analysis. Narcolepsy patients exhibited higher prevalence of obesity (log OR = 0.93 [0.73-1.13], P < 0.001), diabetes mellitus (log OR = 0.64 [0.34, 0.94], P < 0.001), hypertension (log OR = 0.33 [0.11, 0.55], P < 0.001), and dyslipidemia (log OR = 1.19 [0.60, 1.77], P < 0.001) compared with non-narcoleptic controls. Narcolepsy was associated with higher BMI (SMD = 0.50 [0.32-0.68], P < 0.001), waist circumference (MD = 8.61 [2.03-15.19], P = 0.01), and plasma insulin (SMD = 0.61 [0.14-1.09], P = 0.01). Levels of fasting blood glucose (SMD = -0.25 [-0.61,0.10], P = 0.15), BMR-RMR (SMD = -0.17 [-0.52-0.18], P = 0.34), systolic blood pressure (SMD = 0.29 [-0.39-0.97], P = 0.40), diastolic blood pressure (SMD = 0.39 [-0.62, 1.40], P = 0.45), CSF melanin-concentrating hormone (MD = 5.56 [-30.79-41.91], P = 0.76), serum growth hormone (SMD = 7.84 [-7.90-23.57], P = 0.33), as well as plasma and CSF leptin (SMD = 0.10 [-1.32-1.51], P = 0.89 and MD = 0.01 [-0.02-0.04], P = 0.56, respectively) did not significantly differ between narcolepsy patients and controls. These findings necessitate early screening of metabolic alterations and cardiovascular risk factors in narcolepsy patients to reduce the morbidity and mortality rates.
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Affiliation(s)
- Soheil Mohammadi
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Tehran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Moosaie
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Tehran University of Medical Sciences, Tehran, Iran
| | - Amene Saghazadeh
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; MetaCognition Interest Group (MCIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Maryam Mahmoudi
- Department of Cellular Molecular Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran; Dietitians and Nutrition Experts Team (DiNET), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
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4
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Dunietz GL, Vanini G, Shannon C, O'Brien LM, Chervin RD. Associations of plasma hypocretin-1 with metabolic and reproductive health: Two systematic reviews of clinical studies. Sleep Med Rev 2020; 52:101307. [PMID: 32259696 PMCID: PMC7351596 DOI: 10.1016/j.smrv.2020.101307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 12/11/2022]
Abstract
The hypocretin system consists of two peptides hypocretin-1 and hypocretin-2 (HCRT1 and HCRT2). Hypocretin-containing neurons are located in the posterior and lateral hypothalamus, and have widespread projections throughout the brain and spinal cord. In addition to its presence in the cerebrospinal fluid (CSF), peripheral HCRT1 has been detected in plasma. Robust experimental evidence demonstrates functions of hypothalamic-originated HCRT1 in regulation of multiple biological systems related to sleep-wake states, energy homeostasis and endocrine function. In contrast, HCRT1 studies with human participants are limited by the necessarily invasive assessment of CSF HCRT1 to patients with underlying morbidity. Regulation by HCRT1 of energy homeostasis and reproduction in animals suggests similar regulation in humans and prompts these two systematic reviews. These reviews translate prior experimental findings from animal studies to humans and examine associations between HCRT1 and: 1) metabolic risk factors; 2) reproductive function in men, women and children. A total of 21 studies and six studies met the inclusion criteria for the two searches, respectively. Research question, study design, study population, assessments of HCRT1, reproductive, cardiometabolic data and main findings were extracted. Associations between HCRT1, metabolic and reproductive function are inconsistent. Limitations of studies and future research directions are outlined.
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Affiliation(s)
- Galit L Dunietz
- Division of Sleep Medicine, Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Giancarlo Vanini
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Carol Shannon
- Taubman Health Sciences Library, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Louise M O'Brien
- Division of Sleep Medicine, Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Obstetrics & Gynecology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ronald D Chervin
- Division of Sleep Medicine, Department of Neurology, University of Michigan, Ann Arbor, MI, 48109, USA
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5
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Bornstein A, Hedström A, Wasling P. Actigraphy measurement of physical activity and energy expenditure in narcolepsy type 1, narcolepsy type 2 and idiopathic hypersomnia: A Sensewear Armband study. J Sleep Res 2020; 30:e13038. [PMID: 32281246 DOI: 10.1111/jsr.13038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/10/2020] [Accepted: 03/13/2020] [Indexed: 11/28/2022]
Abstract
The cause of obesity in narcolepsy type 1 (NT1) patients is not fully understood. The present study investigated if a reduced physical activity could explain weight gain in NT1. Seventy-nine patients were included in this retrospective study and divided into an NT1 group (n = 56) and a non-NT1 group (n = 23), including NT2 and idiopathic hypersomnia (IH). Accelerometry-derived measures of physical activity, total energy expenditure and skin temperature were collected from patients during seven consecutive days without medication. In addition, results from multiple sleep latency tests and the Epworth Sleepiness Scale questionnaire, body weight, height and CSF orexin/hypocretin were acquired. Three measurements of physical activity, including metabolic equivalent of task (MET), the average time of physical activity and step count, were compared without differences between groups. Neither could we find a significant difference in total energy expenditure or skin temperature. Thus, by analysing accelerometric data, we could not find any differences in the amount of physical activity or total energy expenditure explaining overweight in NT1.
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Affiliation(s)
- Axel Bornstein
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anders Hedström
- Department of Clinical Neurophysiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Pontus Wasling
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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6
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Untangling narcolepsy and diabetes: Pathomechanisms with eyes on therapeutic options. Brain Res 2019; 1718:212-222. [DOI: 10.1016/j.brainres.2019.04.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/23/2019] [Accepted: 04/13/2019] [Indexed: 12/14/2022]
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7
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Sahni AS, Carlucci M, Malik M, Prasad B. Management Of Excessive Sleepiness In Patients With Narcolepsy And OSA: Current Challenges And Future Prospects. Nat Sci Sleep 2019; 11:241-252. [PMID: 31695533 PMCID: PMC6815780 DOI: 10.2147/nss.s218402] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/09/2019] [Indexed: 01/09/2023] Open
Abstract
Excessive daytime sleepiness (EDS) can be caused by insufficient sleep but is also a manifestation of medical or sleep disorders and a side effect of medications. It impacts quality of life and creates safety concerns in the home, at work, and on the roads. Screening questionnaires can be used to estimate EDS, but further evaluation is necessary. EDS is a common symptom of both narcolepsy and obstructive sleep apnea (OSA). Polysomnography and multiple sleep latency testing are used to diagnose these disorders. However, isolating the primary etiology of EDS can be challenging and may be multifactorial. Untreated OSA can show polysomnographic findings that are similar to narcolepsy. The effects of sleep deprivation and certain medications can also affect the polysomnographic results. These challenges can lead to misdiagnosis. In addition, narcolepsy and OSA can occur as comorbid disorders. If EDS persists despite adequate treatment for either disorder, a comorbid diagnosis should be sought. Thus, despite advances in clinical practice, appropriate management of these patients can be challenging. This review is focused on EDS due to OSA and narcolepsy and addresses some of the challenges with managing this patient population.
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Affiliation(s)
- Ashima S Sahni
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Melissa Carlucci
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Malik Malik
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Bharati Prasad
- Division of Pulmonary, Critical Care, Sleep and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
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8
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Kim H, Song JH, Kim TW, Kim SM, Um YH, Oh JH, Cho IH, Hong SC. Comorbidity of Narcolepsy and Obstructive Sleep Apnea: A Case Report. SLEEP MEDICINE RESEARCH 2018. [DOI: 10.17241/smr.2018.00297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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9
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Hayakawa K, Sakamoto Y, Kanie O, Ohtake A, Daikoku S, Ito Y, Shiota K. Reactivation of hyperglycemia-induced hypocretin (HCRT) gene silencing by N-acetyl-d-mannosamine in the orexin neurons derived from human iPS cells. Epigenetics 2017; 12:764-778. [PMID: 28762874 DOI: 10.1080/15592294.2017.1346775] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Orexin neurons regulate critical brain activities for controlling sleep, eating, emotions, and metabolism, and impaired orexin neuron function results in several neurologic disorders. Therefore, restoring normal orexin function and understanding the mechanisms of loss or impairment of orexin neurons represent important goals. As a step toward that end, we generated human orexin neurons from induced pluripotent stem cells (hiPSCs) by treatment with N-acetyl-d-mannosamine (ManNAc) and its derivatives. The generation of orexin neurons was associated with DNA hypomethylation, histone H3/H4 hyperacetylation, and hypo-O-GlcNAcylation on the HCRT gene locus, and, thereby, the treatment of inhibitors of SIRT1 and OGT were effective at inducing orexin neurons from hiPSCs. The prolonged exposure of orexin neurons to high glucose in culture caused irreversible silencing of the HCRT gene, which was characterized by H3/H4 hypoacetylation and hyper-O-GlcNAcylation. The DNA hypomethylation status, once established in orexin neurogenesis, was maintained in the HCRT-silenced orexin neurons, indicating that histone modifications, but not DNA methylation, were responsible for the HCRT silencing. Thus, the epigenetic status of the HCRT gene is unique to the hyperglycemia-induced silencing. Intriguingly, treatment of ManNAc and its derivatives reactivated HCRT gene expression, while inhibitors SIRT1 and the OGT did not. The present study revealed that the HCRT gene was silenced by the hyperglycemia condition, and ManNAc and its derivatives were useful for restoring the orexin neurons.
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Affiliation(s)
- Koji Hayakawa
- a Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences/Veterinary Medical Sciences , The University of Tokyo , Tokyo , Japan
| | - Yasuharu Sakamoto
- b Synthetic Cellular Chemistry Laboratory , RIKEN , 2-1 Hirosawa, Wako , Saitama , Japan
| | - Osamu Kanie
- c Japan Science and Technology Agency ERATO Glycotrilogy Project , 2-1 Hirosawa, Wako , Saitama , Japan.,d Present address: Institute of Advanced Biosciences, Tokai University , 4-1-1 Kitakaname, Hiratsuka , Kanagawa , Japan
| | - Atsuko Ohtake
- c Japan Science and Technology Agency ERATO Glycotrilogy Project , 2-1 Hirosawa, Wako , Saitama , Japan
| | - Shusaku Daikoku
- c Japan Science and Technology Agency ERATO Glycotrilogy Project , 2-1 Hirosawa, Wako , Saitama , Japan
| | - Yukishige Ito
- b Synthetic Cellular Chemistry Laboratory , RIKEN , 2-1 Hirosawa, Wako , Saitama , Japan.,c Japan Science and Technology Agency ERATO Glycotrilogy Project , 2-1 Hirosawa, Wako , Saitama , Japan
| | - Kunio Shiota
- a Laboratory of Cellular Biochemistry, Department of Animal Resource Sciences/Veterinary Medical Sciences , The University of Tokyo , Tokyo , Japan.,e Waseda Research Institute for Science and Engineering, Waseda University , Tokyo , Japan
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10
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The link between narcolepsy and autonomic cardiovascular dysfunction: a translational perspective. Clin Auton Res 2017; 28:545-555. [DOI: 10.1007/s10286-017-0473-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/25/2017] [Indexed: 01/09/2023]
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11
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Cremaschi RC, Hirotsu C, Tufik S, Coelho FM. Narcolepsy type 1 and type 2 - a 10-year follow-up: body mass index and comorbidities. Sleep Med 2017; 32:285-286. [PMID: 28065686 DOI: 10.1016/j.sleep.2016.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 12/09/2016] [Indexed: 10/20/2022]
Affiliation(s)
- Renata Carvalho Cremaschi
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil; Department of Neurology and Neurosurgery, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Camila Hirotsu
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Sergio Tufik
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fernando Morgadinho Coelho
- Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil; Department of Neurology and Neurosurgery, Universidade Federal de São Paulo, São Paulo, Brazil.
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12
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van Holst RJ, van der Cruijsen L, van Mierlo P, Lammers GJ, Cools R, Overeem S, Aarts E. Aberrant Food Choices after Satiation in Human Orexin-Deficient Narcolepsy Type 1. Sleep 2016; 39:1951-1959. [PMID: 27568806 DOI: 10.5665/sleep.6222] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/21/2016] [Indexed: 12/26/2022] Open
Abstract
STUDY OBJECTIVES Besides influencing vigilance, orexin neurotransmission serves a variety of functions, including reward, motivation, and appetite regulation. As obesity is an important symptom in orexin-deficient narcolepsy, we explored the effects of satiety on food-related choices and spontaneous snack intake in patients with narcolepsy type 1 (n = 24) compared with healthy matched controls (n = 19). In additional analyses, we also included patients with idiopathic hypersomnia (n = 14) to assess sleepiness-related influences. METHODS Participants were first trained on a choice task to earn salty and sweet snacks. Next, one of the snack outcomes was devalued by having participants consume it until satiation (i.e., sensory-specific satiety). We then measured the selective reduction in choices for the devalued snack outcome. Finally, we assessed the number of calories that participants consumed spontaneously from ad libitum available snacks afterwards. RESULTS After satiety, all participants reported reduced hunger and less wanting for the devalued snack. However, while controls and idiopathic hypersomnia patients chose the devalued snack less often in the choice task, patients with narcolepsy still chose the devalued snack as often as before satiety. Subsequently, narcolepsy patients spontaneously consumed almost 4 times more calories during ad libitum snack intake. CONCLUSIONS We show that the manipulation of food-specific satiety has reduced effects on food choices and caloric intake in narcolepsy type 1 patients. These mechanisms may contribute to their obesity, and suggest an important functional role for orexin in human eating behavior. CLINICAL TRIALS REGISTRATION Study registered at Netherlands Trial Register. URL: www.trialregister.nl. Trial ID: NTR4508.
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Affiliation(s)
- Ruth Janke van Holst
- Department of Neurology, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.,Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands
| | | | | | - Gert Jan Lammers
- Sleep-Wake Center SEIN, Heemstede, The Netherlands.,Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Roshan Cools
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.,Department of Psychiatry, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sebastiaan Overeem
- Department of Neurology, Radboud University Medical Center, Nijmegen, The Netherlands.,Sleep Medicine Center Kempenhaeghe, Heeze, The Netherlands.,Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Esther Aarts
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
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13
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Rives-Lange C, Karsenty A, Chantereau H, Oderda L, Dubern B, Lecendreux M, Tounian P. [Narcolepsy in sleepy obese children. Two case reports]. Arch Pediatr 2016; 23:603-6. [PMID: 27133373 DOI: 10.1016/j.arcped.2016.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 10/26/2015] [Accepted: 03/11/2016] [Indexed: 11/17/2022]
Abstract
Narcolepsy is a disabling disorder, characterized by excessive daytime sleepiness, irresistible sleep attacks, and partial or complete cataplexy. Many cases of obesity and precocious puberty have been reported in narcoleptic children, suggesting that the deficiency of hypocretin in narcolepsy could also be implicated in appetite stimulation. We report the observations of two young girls, who were referred for obesity and who developed narcolepsy accompanied by an abrupt weight gain. In both cases, specific drugs promoted wakefulness and overweight stabilization. Narcolepsy has to be suspected in sleepy obese children and not misdiagnosed as obstructive apnea. A nocturnal polysomnography with multiple sleep latency tests should be performed to confirm the diagnosis and begin specific treatment that is effective for sleep disorders and weight gain.
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Affiliation(s)
- C Rives-Lange
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France
| | - A Karsenty
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France.
| | - H Chantereau
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France
| | - L Oderda
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France
| | - B Dubern
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France
| | - M Lecendreux
- Centre pédiatrique des pathologies du sommeil, CHU Robert-Debré, AP-HP, 48, boulevard Serrurier, 75019 Paris, France; CNR narcolepsie-hypersomnie, 75019 Paris, France
| | - P Tounian
- Service de nutrition et gastro-entérologie pédiatriques, hôpital Trousseau, AP-HP, université Paris 6, 26, avenue du Dr-Arnold-Netter, 75012 Paris, France
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14
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Black SW, Yamanaka A, Kilduff TS. Challenges in the development of therapeutics for narcolepsy. Prog Neurobiol 2015; 152:89-113. [PMID: 26721620 DOI: 10.1016/j.pneurobio.2015.12.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/14/2015] [Accepted: 12/04/2015] [Indexed: 01/19/2023]
Abstract
Narcolepsy is a neurological disorder that afflicts 1 in 2000 individuals and is characterized by excessive daytime sleepiness and cataplexy-a sudden loss of muscle tone triggered by positive emotions. Features of narcolepsy include dysregulation of arousal state boundaries as well as autonomic and metabolic disturbances. Disruption of neurotransmission through the hypocretin/orexin (Hcrt) system, usually by degeneration of the HCRT-producing neurons in the posterior hypothalamus, results in narcolepsy. The cause of Hcrt neurodegeneration is unknown but thought to be related to autoimmune processes. Current treatments for narcolepsy are symptomatic, including wake-promoting therapeutics that increase presynaptic dopamine release and anticataplectic agents that activate monoaminergic neurotransmission. Sodium oxybate is the only medication approved by the US Food and Drug Administration that alleviates both sleep/wake disturbances and cataplexy. Development of therapeutics for narcolepsy has been challenged by historical misunderstanding of the disease, its many disparate symptoms and, until recently, its unknown etiology. Animal models have been essential to elucidating the neuropathology underlying narcolepsy. These models have also aided understanding the neurobiology of the Hcrt system, mechanisms of cataplexy, and the pharmacology of narcolepsy medications. Transgenic rodent models will be critical in the development of novel therapeutics for the treatment of narcolepsy, particularly efforts directed to overcome challenges in the development of hypocretin replacement therapy.
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Affiliation(s)
- Sarah Wurts Black
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, CA 94025, USA
| | - Akihiro Yamanaka
- Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan
| | - Thomas S Kilduff
- Center for Neuroscience, Biosciences Division, SRI International, Menlo Park, CA 94025, USA.
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Jacob L, Dauvilliers Y. La narcolepsie avec cataplexie : une maladie auto-immune ? Med Sci (Paris) 2014; 30:1136-43. [DOI: 10.1051/medsci/20143012017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Zink AN, Perez-Leighton CE, Kotz CM. The orexin neuropeptide system: physical activity and hypothalamic function throughout the aging process. Front Syst Neurosci 2014; 8:211. [PMID: 25408639 PMCID: PMC4219460 DOI: 10.3389/fnsys.2014.00211] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/07/2014] [Indexed: 12/18/2022] Open
Abstract
There is a rising medical need for novel therapeutic targets of physical activity. Physical activity spans from spontaneous, low intensity movements to voluntary, high-intensity exercise. Regulation of spontaneous and voluntary movement is distributed over many brain areas and neural substrates, but the specific cellular and molecular mechanisms responsible for mediating overall activity levels are not well understood. The hypothalamus plays a central role in the control of physical activity, which is executed through coordination of multiple signaling systems, including the orexin neuropeptides. Orexin producing neurons integrate physiological and metabolic information to coordinate multiple behavioral states and modulate physical activity in response to the environment. This review is organized around three questions: (1) How do orexin peptides modulate physical activity? (2) What are the effects of aging and lifestyle choices on physical activity? (3) What are the effects of aging on hypothalamic function and the orexin peptides? Discussion of these questions will provide a summary of the current state of knowledge regarding hypothalamic orexin regulation of physical activity during aging and provide a platform on which to develop improved clinical outcomes in age-associated obesity and metabolic syndromes.
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Affiliation(s)
- Anastasia N Zink
- Graduate Program in Neuroscience, School of Medicine, University of Minnesota Minneapolis, MN, USA
| | | | - Catherine M Kotz
- Graduate Program in Neuroscience, School of Medicine, University of Minnesota Minneapolis, MN, USA ; GRECC (11G), Minneapolis VA Healthcare System Minneapolis, MN, USA ; Department of Food Science and Nutrition, University of Minnesota Saint Paul, MN, USA
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Abstract
Sleep and circadian rhythms modulate or control daily physiological patterns with importance for normal metabolic health. Sleep deficiencies associated with insufficient sleep schedules, insomnia with short-sleep duration, sleep apnea, narcolepsy, circadian misalignment, shift work, night eating syndrome, and sleep-related eating disorder may all contribute to metabolic dysregulation. Sleep deficiencies and circadian disruption associated with metabolic dysregulation may contribute to weight gain, obesity, and type 2 diabetes potentially by altering timing and amount of food intake, disrupting energy balance, inflammation, impairing glucose tolerance, and insulin sensitivity. Given the rapidly increasing prevalence of metabolic diseases, it is important to recognize the role of sleep and circadian disruption in the development, progression, and morbidity of metabolic disease. Some findings indicate sleep treatments and countermeasures improve metabolic health, but future clinical research investigating prevention and treatment of chronic metabolic disorders through treatment of sleep and circadian disruption is needed.
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Affiliation(s)
- Christopher M. Depner
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado at Boulder, Boulder, CO, 80309 USA
| | - Ellen R. Stothard
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado at Boulder, Boulder, CO, 80309 USA
| | - Kenneth P. Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado at Boulder, Boulder, CO, 80309 USA
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045 USA
- Corresponding author Mailing Address and Phone for all authors: 1725 Pleasant Street, Clare Small 114, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309-0354, Phone: 303-735-1923, Fax: 303-492-4009
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Ohayon MM, Black J, Lai C, Eller M, Guinta D, Bhattacharyya A. Increased mortality in narcolepsy. Sleep 2014; 37:439-44. [PMID: 24587565 DOI: 10.5665/sleep.3470] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE To evaluate the mortality rate in patients with narcolepsy. DESIGN Data were derived from a large database representative of the US population, which contains anonymized patient-linked longitudinal claims for 173 million individuals. SETTING Symphony Health Solutions (SHS) Source Lx, an anonymized longitudinal patient dataset. PATIENTS/PARTICIPANTS All records of patients registered in the SHS database between 2008 and 2010. INTERVENTIONS None. MEASUREMENTS AND RESULTS Identification of patients with narcolepsy was based on ≥ 1 medical claim with the diagnosis of narcolepsy (ICD-9 347.xx) from 2002 to 2012. Dates of death were acquired from the Social Security Administration via a third party; the third party information was encrypted in the same manner as the claims data such that anonymity is ensured prior to receipt by SHS. Annual all-cause mortality rates for 2008, 2009, and 2010 were calculated retrospectively for patients with narcolepsy and patients without narcolepsy in the database, and standardized mortality ratios (SMR) were calculated. Mortality rates were also compared with the general US population (Centers for Disease Control data). SMRs of the narcolepsy population were consistent over the 3-year period and showed an approximate 1.5-fold excess mortality relative to those without narcolepsy. The narcolepsy population had consistently higher mortality rates relative to those without narcolepsy across all age groups, stratified by age decile, from 25-34 years to 75+ years of age. The SMR for females with narcolepsy was lower than for males with narcolepsy. CONCLUSIONS Narcolepsy was associated with approximately 1.5-fold excess mortality relative to those without narcolepsy. While the cause of this increased mortality is unknown, these findings warrant further investigation.
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Affiliation(s)
- Maurice M Ohayon
- Stanford Sleep Epidemiology Research Center, Stanford University, Palo Alto, CA
| | - Jed Black
- Stanford Center for Sleep Sciences and Medicine, Stanford University School of Medicine, Stanford, CA
| | | | - Mark Eller
- Jazz Pharmaceuticals, Inc., Palo Alto, CA
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Frauscher B, Ehrmann L, Mitterling T, Gabelia D, Gschliesser V, Brandauer E, Poewe W, Högl B. Delayed diagnosis, range of severity, and multiple sleep comorbidities: a clinical and polysomnographic analysis of 100 patients of the innsbruck narcolepsy cohort. J Clin Sleep Med 2013; 9:805-12. [PMID: 23946711 DOI: 10.5664/jcsm.2926] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
STUDY OBJECTIVES Narcolepsy is reported to affect 26-56/100,000 in the general population. We aimed to describe clinical and polysomnographic features of a large narcolepsy cohort in order to comprehensively characterize the narcoleptic spectrum. METHODS We performed a chart- and polysomnographybased review of all narcolepsy patients of the Innsbruck narcolepsy cohort. RESULTS A total of 100 consecutive narcolepsy patients (87 with cataplexy [NC], 13 without cataplexy [N]) were included in the analysis. All subjects had either excessive daytime sleepiness or cataplexy as their initial presenting clinical feature. Age at symptom onset was 20 (6-69) years. Diagnostic delay was 6.5 (0-39) years. The complete narcolepsy tetrad was present in 36/100 patients; 28/100 patients had three cardinal symptoms; 29/100 had two; and 7/100 had only excessive daytime sleepiness. Severity varied broadly with respect to excessive daytime sleepiness (median Epworth Sleepiness Scale score: 18, range 10-24), cataplexy (8-point Likert scale: median 4.5, range 1-8), hypnagogic hallucinations (median 4.5, range 1-7), and sleep paralysis (median 3, range 1-7). Sleep comorbidity was highly prevalent and ranged from sleeprelated movement disorders (n = 55/100), parasomnias (n = 34/100), and sleeprelated breathing disorders (n = 24/100), to insomnia (n = 28/100). REM sleep without atonia or a periodic limb movement in sleep index > 5/h were present in most patients (90/100 and 75/100). A high percentage of narcoleptic patients in the present study had high frequency leg movements (35%) and excessive fragmentary myoclonus (22%). Of the narcolepsy patients with clinical features of REM sleep behavior disorder (RBD), 76.5% had EMG evidence for RBD on the multiple sleep latency test (MSLT), based on a standard cutoff of a minimum of 18% of 3-sec miniepochs. CONCLUSION This study is one of the largest monocentric polysomnographic studies to date of patients with narcolepsy and confirms the frequent comorbidity of narcolepsy with many other sleep disorders. Our study is the first to evaluate the percentage of patients with high frequency leg movements and excessive fragmentary myoclonus in narcolepsy and is the first to demonstrate EMG evidence of RBD in the MSLT. These findings add to the growing body of literature suggesting that motor instability is a key feature of narcolepsy.
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Affiliation(s)
- Birgit Frauscher
- Innsbruck Medical University, Department of Neurology, Innsbruck, Austria
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Jennum P, Ibsen R, Knudsen S, Kjellberg J. Comorbidity and mortality of narcolepsy: a controlled retro- and prospective national study. Sleep 2013; 36:835-40. [PMID: 23729926 DOI: 10.5665/sleep.2706] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
STUDY OBJECTIVES To identify the factual morbidity and mortality of narcolepsy in a controlled design. SETTING National Patient Registry. PATIENTS All national diagnosed patients (757) with health information at least 3 years prior to and after diagnose of narcolepsy. CONTROLS Randomly selected four citizens (3,013) matched for age, sex, and socioeconomic status from the Danish Civil Registration System Statistics. RESULTS Increased morbidity prior to narcolepsy diagnosis included (odds ratio, 95% confidence interval):- diseases of the endocrine, nutritional, and metabolic systems (2.10, 1.32-3.33); nervous system (5.27, 3.65-7.60); musculoskeletal system (1.59, 1.23-2.05); and other abnormal symptoms and laboratory findings (1.66, 1.25-2.22). After the diagnosis, narcolepsy patients experienced diseases of the endocrine, nutritional, and metabolic (2.31, 1.51-3.54), nervous (9.19, 6.80-12.41), musculoskeletal (1.70, 1.28-2.26), eye (1.67, 1.03-2.71), and respiratory systems (1.84, 1.21-2.81). Specific diagnoses were diabetes (2.4, 1,2-4.7, P < 0.01), obesity (13.4, 3.1-57.6, P < 0.001), sleep apnea (19.2, 7.7-48.3, P < 0.001), other sleep disorders (78.5, 11.8-523.3, P < 0.001), chronic obstructive pulmonary disease (2.8, 1.4-5.8, P < 0.01), lower back pain (2.5, 1.4-4.2, P < 0.001), arthrosis/arthritis (2.5, 1.3-4.8, P < 0.01), observation of neurological diseases (3.5, 1.9-6.5, P < 0.001), observation of other diseases (1.7, 1.2-2.5, P < 0.01), and rehabilitation (5.0, 1.5-16.5, P < 0.005). There was a trend towards greater mortality in narcolepsy (P = 0.07). CONCLUSIONS Patients with narcolepsy present higher morbidity several years prior to diagnose and even higher thereafter. The mortality rate due to narcolepsy was slightly but not significantly higher.
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Affiliation(s)
- Poul Jennum
- Danish Center for Sleep Medicine, Department of Clinical Neurophysiology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Glostrup Hospital, Copenhagen, Denmark.
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Jennum P, Mayer G, Ju YE, Postuma R. Morbidities in rapid eye movement sleep behavior disorder. Sleep Med 2013; 14:782-7. [PMID: 23375425 DOI: 10.1016/j.sleep.2012.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 10/11/2012] [Accepted: 11/05/2012] [Indexed: 12/20/2022]
Abstract
Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD, RBD without any obvious comorbid major neurological disease), is strongly associated with numerous comorbid conditions. The most prominent is that with neurodegenerative disorders, especially synuclein-mediated disorders, above all Parkinson disease (PD). Idiopathic RBD is an important risk factor for the development of synucleinopathies. Comorbidity studies suggest that iRBD is associated with a number of other potential pre-motor manifestations of synucleinopathies such as, cognitive and olfactory impairment, reduced autonomic function, neuropsychiatric manifestations and sleep complaints. Furthermore, patients with PD and RBD may have worse prognosis in terms of impaired cognitive function and overall morbidity/mortality; in dementia, the presence of RBD is strongly associated with clinical hallmarks and pathological findings of dementia with Lewy bodies. These findings underline the progressive disease process, suggesting involvement of more brain regions in patients with a more advanced disease stage. RBD is also associated with narcolepsy, and it is likely that RBD associated with narcolepsy is a distinct subtype associated with different comorbidities. RBD is also associated with antidepressant medications, autoimmune conditions, and, in rare cases, brainstem lesions.
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Affiliation(s)
- Poul Jennum
- Danish Center for Sleep Medicine, Department of Clinical Neurophysiology, University of Copenhagen, Glostrup, Copenhagen, Denmark.
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Abstract
OPINION STATEMENT Dyssomnias are sleep disorders associated with complaints of insomnia or hypersomnia. The daytime sleepiness of narcolepsy is treated by a combination of planned daytime naps, regular exercise medications such as modafinil, or salts of methylphenidate, or amphetamine. Cataplexy that accompanies narcolepsy is treated with anticholinergic agents, selective serotonin reuptake inhibitors, or sodium oxybate. Children with neurodevelopmental disabilities such as autism have sleep initiation and maintenance difficulties on a multifactorial basis, with favorable response to melatonin in some patients. Childhood onset restless legs syndrome is often familial, associated with systemic iron deficiency, and responsive to iron supplementation and gabapentin. Parasomnias are episodic phenomena events which occur at the sleep -- wake transition or by intrusion on to sleep. Arousal parasomnias such as confusional arousals and sleep walking can sometimes be confused with seizures. A scheme for differentiating arousal parasomnias from nocturnal seizures is provided. Since arousal parasomnias are often triggered by sleep apnea, restless legs syndrome, or acid reflux, treatment measures directed specifically at these disorders often helps in resolution. Clonazepam provided in a low dose at bedtime can also alleviate sleep walking and confusional arousals. Obstructive sleep apnea affects about 2 percent of children. Adeno-tonsillar hypertrophy, cranio-facial anomalies, and obesity are common predisposing factors. Mild obstructive sleep apnea can be treated using a combination of nasal corticosteroids and a leukotriene antagonist. Moderate to severe obstructive sleep apnea are treated with adeno-tonsillectomy, positive airway pressure breathing devices, or weight reduction as indicated. This paper provides an overview of the topic, with an emphasis on management steps. Where possible, the level of evidence for treatment recommendations is indicated.
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Affiliation(s)
- Suresh Kotagal
- Neurology, Pediatrics and the Center for Sleep Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA,
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