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Ronderos-Botero DM, Dileep A, Yapor L, Singhal R. Disruption of cardio-pulmonary coupling in myopathies: Pathophysiological and mechanistic characterization with special emphasis on nemaline myopathy. Front Cardiovasc Med 2022; 9:996567. [DOI: 10.3389/fcvm.2022.996567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 09/30/2022] [Indexed: 11/09/2022] Open
Abstract
The heart and lung are in continuous reciprocal interaction that creates a functional and anatomical reserve referred to as cardiopulmonary coupling (CPC). Disruption of CPC can occur due to various cardiac or pulmonary pathologies but also can occur in patients with myopathies. Nemaline myopathy (NM) is a skeletal muscle heterogeneous disorder due to contractile proteins' gene mutations that impact lung and cardiac mechanics and thus is expected to adversely affect CPC in a complex manner. We present a case of NM and we review the literature on cardiac and pulmonary effects of myopathy-related disruption of CPC.
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Hamilton MJ, Atalaia A, McLean J, Cumming SA, Evans JJ, Ballantyne B, Jampana R, The Scottish Myotonic Dystrophy Consortium, Longman C, Livingston E, van der Plas E, Koscik T, Nopoulos P, Farrugia ME, Monckton DG. Clinical and neuroradiological correlates of sleep in myotonic dystrophy type 1. Neuromuscul Disord 2022; 32:377-389. [PMID: 35361525 DOI: 10.1016/j.nmd.2022.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 01/15/2022] [Accepted: 02/09/2022] [Indexed: 10/19/2022]
Abstract
Abnormalities of sleep are common in myotonic dystrophy type 1 (DM1), but few previous studies have combined polysomnography with detailed clinical measures and brain imaging. In the present study, domiciliary polysomnography, symptom questionnaires and cognitive evaluation were undertaken in 39 DM1-affected individuals. Structural brain MRI was completed in those without contra-indication (n = 32). Polysomnograms were adequate for analysis in 36 participants. Sleep efficiency was reduced, and sleep architecture altered in keeping with previous studies. Twenty participants (56%) had moderate or severe sleep-disordered breathing (apnoea-hypopnoea index [AHI] ≥ 15). In linear modelling, apnoeas were positively associated with increasing age and male sex. AHI ≥ 15 was further associated with greater daytime pCO2 and self-reported physical impairment, somnolence and fatigue. Percentage REM sleep was inversely associated with cerebral grey matter volume, stage 1 sleep was positively associated with occipital lobe volume and stage 2 sleep with amygdala volume. Hippocampus volume was positively correlated with self-reported fatigue and somnolence. Linear relationships were also observed between measures of sleep architecture and cognitive performance. Findings broadly support the hypothesis that changes in sleep architecture and excessive somnolence in DM1 reflect the primary disease process in the central nervous system.
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Affiliation(s)
- Mark J Hamilton
- West of Scotland Clinical Genetics Service, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK; Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
| | - Antonio Atalaia
- Sorbonne Université, Inserm, Center of Research in Myology, UMRS 974, Institut de Myologie, G.H . Pitié-Salpêtrière, Paris, France
| | - John McLean
- Department of Neuroradiology, Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | - Sarah A Cumming
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Jonathan J Evans
- Institute of Health and Wellbeing, University of Glasgow, Gartnavel Royal Hospital, Glasgow, UK G12 0XH
| | - Bob Ballantyne
- West of Scotland Clinical Genetics Service, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | - Ravi Jampana
- Department of Neuroradiology, Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | | | - Cheryl Longman
- West of Scotland Clinical Genetics Service, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | - Eric Livingston
- Department of Respiratory Medicine, Glasgow Royal Infirmary, Glasgow G4 0SF, UK
| | - Ellen van der Plas
- Department of Psychiatry, University of Iowa Hospital and Clinics, Iowa City, IA, USA
| | - Timothy Koscik
- Department of Psychiatry, University of Iowa Hospital and Clinics, Iowa City, IA, USA
| | - Peggy Nopoulos
- Department of Psychiatry, University of Iowa Hospital and Clinics, Iowa City, IA, USA
| | - Maria Elena Farrugia
- Department of Neurology, Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | - Darren G Monckton
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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Weijs R, Okkersen K, van Engelen B, Küsters B, Lammens M, Aronica E, Raaphorst J, van Cappellen van Walsum AM. Human brain pathology in myotonic dystrophy type 1: A systematic review. Neuropathology 2021; 41:3-20. [PMID: 33599033 PMCID: PMC7986875 DOI: 10.1111/neup.12721] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/01/2020] [Accepted: 11/10/2020] [Indexed: 12/13/2022]
Abstract
Brain involvement in myotonic dystrophy type 1 (DM1) is characterized by heterogeneous cognitive, behavioral, and affective symptoms and imaging alterations indicative of widespread grey and white matter involvement. The aim of the present study was to systematically review the literature on brain pathology in DM1. We conducted a structured search in EMBASE (index period 1974–2017) and MEDLINE (index period 1887–2017) on December 11, 2017, using free text and index search terms related to myotonic dystrophy type 1 and brain structures or regions. Eligible studies were full‐text studies reporting on microscopic brain pathology of DM1 patients without potentially interfering comorbidity. We discussed the findings based on the anatomical region and the nature of the anomaly. Neuropathological findings in DM1 can be classified as follows: (1) protein and nucleotide deposits; (2) changes in neurons and glial cells; and (3) white matter alterations. Most findings are unspecific to DM1 and may occur with physiological aging, albeit to a lesser degree. There are similarities and contrasts with Alzheimer's disease; both show the appearance of neurofibrillary tangles in the limbic system without plaque occurrence. Likewise, there is myelin loss and gliosis, and there are dilated perivascular spaces in the white matter resemblant of cerebral small vessel disease. However, we did not find evidence of lacunar infarction or microbleeding. The various neuropathological findings in DM1 are reflective of the heterogeneous clinical and neuroimaging features of the disease. The strength of conclusions from this study's findings is bounded by limited numbers of participants in studies, methodological constraints, and lack of assessed associations between histopathology and clinical or neuroimaging findings.
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Affiliation(s)
- Ralf Weijs
- Medical Imaging, Anatomy, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands.,Department of Neurology, Donders Institute for Brain Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Kees Okkersen
- Department of Neurology, Donders Institute for Brain Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Baziel van Engelen
- Department of Neurology, Donders Institute for Brain Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Benno Küsters
- Department of Pathology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Martin Lammens
- Department of Pathological Anatomy, University of Antwerp, Antwerp, Belgium
| | - Eleonora Aronica
- Amsterdam UMC, University of Amsterdam, Department of Neurology and Pathology, Amsterdam Neuroscience Institute, Amsterdam, the Netherlands
| | - Joost Raaphorst
- Amsterdam UMC, University of Amsterdam, Department of Neurology and Pathology, Amsterdam Neuroscience Institute, Amsterdam, the Netherlands
| | - Anne-Marie van Cappellen van Walsum
- Medical Imaging, Anatomy, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
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Opioid use may be associated with postoperative complications in myotonic dystrophy type 1 with high-grade muscular impairment. Sci Rep 2021; 11:8. [PMID: 33431966 PMCID: PMC7801477 DOI: 10.1038/s41598-020-76217-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 10/22/2020] [Indexed: 12/25/2022] Open
Abstract
Individuals with myotonic dystrophy type 1 (DM1) reportedly have a higher risk of postoperative complications than those without DM1; however, factors related to perioperative complications in DM1 patients remain unclear. We aimed to identify the risk factors that may be associated with postoperative complications in DM1 patients. We reviewed medical records of 256 patients with DM1 from 1998 to 2018, among whom 42 (16.4%) had previously undergone 51 surgeries under general and regional anaesthesia. Among the 42 patients, 11 (21.5%) had 13 postoperative complications including respiratory complications, sustained hypotension, wound infection and dehiscence, artery thrombosis and occlusion, and delayed recovery from anaesthesia. There were significant inter-group differences between the non-complicated and complicated groups considering the following parameters: high-grade (≥ 3) muscular impairment rating scale (MIRS), extubation time, postoperative opioid use, and hospital length of stay. Furthermore, univariate analysis revealed that an MIRS score ≥ 3 (odds ratio [OR] 9.346, confidence interval [CI] 1.761–49.595, p = 0.009) and postoperative opioid use (OR 8.000, CI 1.772–36.127, p = 0.007) were the only statistically significant factors. Therefore, clinicians should be cautious in administering opioids, particularly in patients with a high-grade MIRS score during the perioperative period.
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Predicting daytime sleepiness and fatigue: a 9-year prospective study in myotonic dystrophy type 1. J Neurol 2019; 267:461-468. [PMID: 31673761 DOI: 10.1007/s00415-019-09592-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/16/2019] [Accepted: 10/17/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Daytime sleepiness and fatigue are prominent symptoms of myotonic dystrophy type I (DM1) that exact a heavy toll on patients' quality of life, but information is scarce on their predictive factors. This study aimed to determine factors that may influence levels of daytime sleepiness and fatigue in a large cohort of DM1 patients followed for 9 years. METHODS This study included 115 patients with DM1 at baseline (Time 1, T1) and at Time 2 (T2) who were questioned for daytime sleepiness, fatigue, history of depression, psychological distress, pain, hypothyroidism, and sleep habits. Also, their muscular impairment and intellectual quotient were evaluated. Regression models were used to identify correlates of daytime sleepiness and fatigue while controlling for time effect. RESULTS Both daytime sleepiness and fatigue increased between T1 and T2, but their rate of change are higher when CTG repeat number is higher (p < 0.05). Also, higher psychological distress level is associated with higher daytime sleepiness and fatigue levels both at T1 and T2 (p < 0.01). Moreover, patients with a history of depression report higher daytime sleepiness levels both at T1 and T2 (p < 0.05). In addition, patients with higher fatigue levels both at T1 and T2 have more severe muscular impairment (p < 0.01) and report a longer habitual sleep duration (p < 0.05). Finally, a higher BMI and a history of hypothyroidism predict higher daytime sleepiness levels at T2 (p < 0.05). CONCLUSION This study identified potentially modifiable risk factors of future daytime sleepiness and fatigue in DM1 patients, including BMI, psychological distress, hypothyroidism, and sleep habits.
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Ho G, Cardamone M, Farrar M. Congenital and childhood myotonic dystrophy: Current aspects of disease and future directions. World J Clin Pediatr 2015; 4:66-80. [PMID: 26566479 PMCID: PMC4637811 DOI: 10.5409/wjcp.v4.i4.66] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/07/2015] [Accepted: 09/25/2015] [Indexed: 02/06/2023] Open
Abstract
Myotonic dystrophy type 1 (DM1) is multisystem disease arising from mutant CTG expansion in the non-translating region of the dystrophia myotonica protein kinase gene. While DM1 is the most common adult muscular dystrophy, with a worldwide prevalence of one in eight thousand, age of onset varies from before birth to adulthood. There is a broad spectrum of clinical severity, ranging from mild to severe, which correlates with number of DNA repeats. Importantly, the early clinical manifestations and management in congenital and childhood DM1 differ from classic adult DM1. In neonates and children, DM1 predominantly affects muscle strength, cognition, respiratory, central nervous and gastrointestinal systems. Sleep disorders are often under recognised yet a significant morbidity. No effective disease modifying treatment is currently available and neonates and children with DM1 may experience severe physical and intellectual disability, which may be life limiting in the most severe forms. Management is currently supportive, incorporating regular surveillance and treatment of manifestations. Novel therapies, which target the gene and the pathogenic mechanism of abnormal splicing are emerging. Genetic counselling is critical in this autosomal dominant genetic disease with variable penetrance and potential maternal anticipation, as is assisting with family planning and undertaking cascade testing to instigate health surveillance in affected family members. This review incorporates discussion of the clinical manifestations and management of congenital and childhood DM1, with a particular focus on hypersomnolence and sleep disorders. In addition, the molecular genetics, mechanisms of disease pathogenesis and development of novel treatment strategies in DM1 will be summarised.
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Cognitive impairment in myotonic dystrophy type 1 is associated with white matter damage. PLoS One 2014; 9:e104697. [PMID: 25115999 PMCID: PMC4130603 DOI: 10.1371/journal.pone.0104697] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/11/2014] [Indexed: 11/19/2022] Open
Abstract
Objective To investigate grey (GM) and white matter (WM) abnormalities and their effects on cognitive and behavioral deficits in a large, phenotypically and genotypically well-characterized cohort of classic adult (aDM1, age at onset ≥20 years) or juvenile (jDM1, age at onset <20 years) patients with myotonic dystrophy type 1 (DM1). Methods A case-control study including 51 DM1 patients (17 jDM1 and 34 aDM1) and 34 controls was conducted at an academic medical center. Clinical, cognitive and structural MRI evaluations were obtained. Quantitative assessments of regional GM volumes, WM hyperintensities (WMHs), and microstructural WM tract damage were performed. The association between structural brain damage and clinical and cognitive findings was assessed. Results DM1 patients showed a high prevalence of WMHs, severe regional GM atrophy including the key nodes of the sensorimotor and main cognitive brain networks, and WM microstructural damage of the interhemispheric, corticospinal, limbic and associative pathways. WM tract damage extends well beyond the focal WMHs. While aDM1 patients had severe patterns of GM atrophy and WM tract damage, in jDM1 patients WM abnormalities exceeded GM involvement. In DM1, WMHs and microstructural damage, but not GM atrophy, correlated with cognitive deficits. Conclusions WM damage, through a disconnection between GM structures, is likely to be the major contributor to cognitive impairment in DM1. Our MRI findings in aDM1 and jDM1 patients support the hypothesis of a degenerative (premature aging) origin of the GM abnormalities and of developmental changes as the principal substrates of microstructural WM alterations in DM1.
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Caillet-Boudin ML, Fernandez-Gomez FJ, Tran H, Dhaenens CM, Buee L, Sergeant N. Brain pathology in myotonic dystrophy: when tauopathy meets spliceopathy and RNAopathy. Front Mol Neurosci 2014; 6:57. [PMID: 24409116 PMCID: PMC3885824 DOI: 10.3389/fnmol.2013.00057] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/20/2013] [Indexed: 01/18/2023] Open
Abstract
Myotonic dystrophy (DM) of type 1 and 2 (DM1 and DM2) are inherited autosomal dominant diseases caused by dynamic and unstable expanded microsatellite sequences (CTG and CCTG, respectively) in the non-coding regions of the genes DMPK and ZNF9, respectively. These mutations result in the intranuclear accumulation of mutated transcripts and the mis-splicing of numerous transcripts. This so-called RNA gain of toxic function is the main feature of an emerging group of pathologies known as RNAopathies. Interestingly, in addition to these RNA inclusions, called foci, the presence of neurofibrillary tangles (NFT) in patient brains also distinguishes DM as a tauopathy. Tauopathies are a group of nearly 30 neurodegenerative diseases that are characterized by intraneuronal protein aggregates of the microtubule-associated protein Tau (MAPT) in patient brains. Furthermore, a number of neurodegenerative diseases involve the dysregulation of splicing regulating factors and have been characterized as spliceopathies. Thus, myotonic dystrophies are pathologies resulting from the interplay among RNAopathy, spliceopathy, and tauopathy. This review will describe how these processes contribute to neurodegeneration. We will first focus on the tauopathy associated with DM1, including clinical symptoms, brain histology, and molecular mechanisms. We will also discuss the features of DM1 that are shared by other tauopathies and, consequently, might participate in the development of a tauopathy. Moreover, we will discuss the determinants common to both RNAopathies and spliceopathies that could interfere with tau-related neurodegeneration.
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Affiliation(s)
- Marie-Laure Caillet-Boudin
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
| | - Francisco-Jose Fernandez-Gomez
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
| | - Hélène Tran
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
| | - Claire-Marie Dhaenens
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
| | - Luc Buee
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
| | - Nicolas Sergeant
- Alzheimer and Tauopathies, Faculty of Medicine, Jean-Pierre Aubert Research Centre, Institute of Predictive Medicine and Therapeutic Research, Inserm, UMR 837 Lille, France ; University of Lille Nord de France, UDSL Lille, France
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Sleep-Wake Cycle and Daytime Sleepiness in the Myotonic Dystrophies. JOURNAL OF NEURODEGENERATIVE DISEASES 2013; 2013:692026. [PMID: 26316996 PMCID: PMC4437277 DOI: 10.1155/2013/692026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 07/19/2013] [Accepted: 08/03/2013] [Indexed: 01/19/2023]
Abstract
Myotonic dystrophy is the most common type of muscular dystrophy in adults and is characterized by progressive myopathy, myotonia, and multiorgan involvement. Two genetically distinct entities have been identified, myotonic dystrophy type 1 (DM1 or Steinert's Disease) and myotonic dystrophy type 2 (DM2). Myotonic dystrophies are strongly associated with sleep dysfunction. Sleep disturbances in DM1 are common and include sleep-disordered breathing (SDB), periodic limb movements (PLMS), central hypersomnia, and REM sleep dysregulation (high REM density and narcoleptic-like phenotype). Interestingly, drowsiness in DM1 seems to be due to a central dysfunction of sleep-wake regulation more than SDB. To date, little is known regarding the occurrence of sleep disorders in DM2. SDB (obstructive and central apnoea), REM sleep without atonia, and restless legs syndrome have been described. Further polysomnographic, controlled studies are strongly needed, particularly in DM2, in order to clarify the role of sleep disorders in the myotonic dystrophies.
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Abstract
Myotonic dystrophy type 1 (DM1) represents the 1 chronic neuromuscular disease with the most prominent sleep disorders, including excessive daytime sleepiness (EDS), sleep apneas, periodic leg movements during sleep, and rapid eye movement sleep dysregulation. The large majority of DM1 patients complain about EDS, which may have a deleterious impact on work, domestic responsibilities, social life, and quality of life. Here, we review the extant literature and report that studies are largely supportive of the view that DM1-related EDS is primarily caused by a central dysfunction of sleep regulation rather than by sleep-related disordered breathing (SRDB) or sleep fragmentation. The pathogenesis of EDS in DM1 still remains unclear but several arguments favor a model in which brain/brainstem nuclear accumulations of toxic expanded DM protein kinase (DMPK) gene are responsible for aberrant genes expression in modifying alternative splicing. Regarding management, early recognition, and treatment of SRDB with nocturnal noninvasive mechanical ventilation is first mandatory. However, despite its appropriate management, EDS often persists and may require a psychostimulant but no consensus has been yet established. Further studies are needed to clarify the discrepancies between daytime sleepiness/fatigue complaints and subjective/objective measurement of daytime sleepiness, the role of cognitive impairment and apathy in this relationship, and its reversibility with appropriate management.
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Shepard P, Lam EM, St Louis EK, Dominik J. Sleep disturbances in myotonic dystrophy type 2. Eur Neurol 2012; 68:377-80. [PMID: 23108384 DOI: 10.1159/000342895] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 08/06/2012] [Indexed: 11/19/2022]
Abstract
Sleep disorders in myotonic dystrophy type 1 (DM1) are common and include sleep-disordered breathing, hypersomnia, and fatigue. Little is known regarding the occurrence of sleep disturbance in myotonic dystrophy type 2 (DM2). We hypothesized that DM2 patients may frequently harbor sleep disorders. We reviewed medical records of all genetically confirmed cases of DM2 seen at our sleep center between 1997 and 2010 for demographic, laboratory, overnight oximetry, and polysomnography (PSG) data. Eight patients (5 women, 3 men) with DM2 were identified. Excessive daytime sleepiness was seen in 6 patients (75%), insomnia in 5 (62.5%), and excessive fatigue in 4 (50%). Obstructive sleep apnea was diagnosed in 3 of 5 patients (60%) studied with PSG. Respiratory muscle weakness was present in all 6 patients (100%) who received pulmonary function testing. Four of 8 (50%) met criteria for diagnosis of restless legs syndrome. The clinical spectrum of DM2 may include a wide range of sleep disturbances. Although respiratory muscle weakness was frequent, sustained sleep-related hypoxia suggestive of hypoventilation was not seen in our patients. Further prospective studies are needed to examine the frequency and scope of sleep disturbances in DM2.
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Affiliation(s)
- Paul Shepard
- Mayo Center for Sleep Medicine, Division of Pulmonary and Critical Care Medicine, Departments of Medicine and Neurology, Mayo Clinic and Foundation, Rochester, MN 55905, USA
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Dauvilliers YA, Laberge L. Myotonic dystrophy type 1, daytime sleepiness and REM sleep dysregulation. Sleep Med Rev 2012; 16:539-45. [PMID: 22465566 DOI: 10.1016/j.smrv.2012.01.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 01/02/2012] [Accepted: 01/07/2012] [Indexed: 12/14/2022]
Abstract
Myotonic dystrophy type 1 (DM1), or Steinert's disease, is the most common adult-onset form of muscular dystrophy. DM1 also constitutes the neuromuscular condition with the most significant sleep disorders including excessive daytime sleepiness (EDS), central and obstructive sleep apneas, restless legs syndrome (RLS), periodic leg movements in wake (PLMW) and periodic leg movements in sleep (PLMS) as well as nocturnal and diurnal rapid eye movement (REM) sleep dysregulation. EDS is the most frequent non-muscular complaint in DM1, being present in about 70-80% of patients. Different phenotypes of sleep-related problems may mimic several sleep disorders, including idiopathic hypersomnia, narcolepsy without cataplexy, sleep apnea syndrome, and periodic leg movement disorder. Subjective and objective daytime sleepiness may be associated with the degree of muscular impairment. However, available evidence suggests that DM1-related EDS is primarily caused by a central dysfunction of sleep regulation rather than by sleep fragmentation, sleep-related respiratory events or periodic leg movements. EDS also tends to persist despite successful treatment of sleep-disordered breathing in DM1 patients. As EDS clearly impacts on physical and social functioning of DM1 patients, studies are needed to identify the best appropriate tools to identify hypersomnia, and clarify the indications for polysomnography (PSG) and multiple sleep latency test (MSLT) in DM1. In addition, further structured trials of assisted nocturnal ventilation and randomized trials of central nervous system (CNS) stimulant drugs in large samples of DM1 patients are required to optimally treat patients affected by this progressive, incurable condition.
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Affiliation(s)
- Yves A Dauvilliers
- National Reference Network for Narcolepsy, Sleep-Disorders Center, Department of Neurology, Hôpital Gui de Chauliac, Inserm U1061, UM1, Montpellier, France.
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Orlikowski D, Chevret S, Quera-Salva MA, Laforêt P, Lofaso F, Verschueren A, Pouget J, Eymard B, Annane D. Modafinil for the treatment of hypersomnia associated with myotonic muscular dystrophy in adults: a multicenter, prospective, randomized, double-blind, placebo-controlled, 4-week trial. Clin Ther 2009; 31:1765-73. [PMID: 19808135 DOI: 10.1016/j.clinthera.2009.08.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Myotonic muscular dystrophy type 1 (MMD1) is the most common form of adult MD, with a mean prevalence of 1 in 8000. Excessive daytime sleepiness (ie, hypersomnia) is a common complication of MMD1. OBJECTIVE The aim of this study was to evaluate the efficacy and tolerability of modafinil for the treatment of hypersomnia in adults with MMD1. METHODS This multicenter, prospective, randomized, double-blind, placebo-controlled study consisted of a prerandomization period (90 to 2 days before randomization) and a 4-week randomization period in which patients were assigned to receive either active treatment (modafinil 300 mg/d) or placebo. The study was conducted at 3 clinics in France between February 2000 and June 2002. Adult patients aged > or =18 years, with genetically proven MMD1, an Epworth Sleepiness Scale (ESS) score >10, and a mean latency to sleep onset < or =8 minutes measured by the Multiple Sleep Latency Test (MSLT) were eligible. The primary efficacy end point was the Maintenance of Wakefulness Test (MWT) score at 4 weeks. Secondary end points included the mean MSLT score and scores from the ESS, physician's assessment of the therapeutic effect and the patient's global self-assessment via visual analog scale, the 17-item Hamilton Depression Rating Scale, and the Short Form Health Survey (SF-36) quality-of-life assessment. RESULTS A total of 28 patients (15 men, 13 women; mean [SD] age, 40 [12.7] years [range, 18-69 years]; 100% white; modafinil group, 13; placebo group, 15) completed the study without protocol violations. Of the 28 patients with MMD1 included in the analysis, 21 had adult-onset MMD1. At 4 weeks, the mean MWT score was 16.4 (3.3) minutes in the modafinil group and 15.8 (3.8) minutes in the placebo group (P = NS). At the end of the randomization period, there were no significant between-group differences in any secondary outcome. A total of 8 patients (4 in each group) reported > or =1 adverse event, including digestive, neurologic, and skin symptoms. Weight loss was reported in 1 patient (2 kg). CONCLUSION In this small study conducted in an adult population with MMD1 and a high prevalence of hyper-somnia, modafinil had no significant effects on daytime somnolence measured using objective MWTs.
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Affiliation(s)
- David Orlikowski
- Center for Neuromuscular Disease, Intensive Care Unit and Sleep Laboratory and Functional Exploration Department, Raymond Poincaré Hospital, Paris Ile de France Ouest, Versailles Saint Quentin University, 92380 Garches, France
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Laberge L, Dauvilliers Y, Bégin P, Richer L, Jean S, Mathieu J. Fatigue and daytime sleepiness in patients with myotonic dystrophy type 1: to lump or split? Neuromuscul Disord 2009; 19:397-402. [PMID: 19403309 DOI: 10.1016/j.nmd.2009.03.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 02/18/2009] [Accepted: 03/23/2009] [Indexed: 10/20/2022]
Abstract
We assessed the relationship and clinical correlates of fatigue and Excessive Daytime Sleepiness (EDS) in 200 myotonic dystrophy type 1 (DM1) patients by means of questionnaire and neuropsychological evaluation. Fatigue levels were higher in patients with EDS and daytime sleepiness levels higher in patients with excessive fatigue. However, EDS without fatigue was rarely observed. Also, DM1 patients with fatigue (with or without EDS) showed greater muscular impairment, CTG repeats, abnormalities regarding personality, depressive symptoms and lower health-related quality of life (HRQoL) than patients without these symptoms. These findings do not readily support the contention that fatigue and EDS constitute distinct clinical manifestations in DM1. Clinicians should systematically evaluate both symptoms since fatigue and EDS have a greater impact on HRQoL than fatigue alone. However, specific rating scales for fatigue in DM1 have yet to be devised.
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Affiliation(s)
- Luc Laberge
- ECOBES, Cégep de Jonquière, Jonquière, Qc, Canada; Département des sciences de l'éducation et de psychologie, Université du Québec à Chicoutimi, 555, boul. de l'Université, Chicoutimi, Qc, Canada G7H 2B1.
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16
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Souayah N, Tick Chong PS, Dreyer M, Cros D, Schmahmann JD. Myotonic dystrophy type 1 presenting with ventilatory failure. J Clin Neuromuscul Dis 2007; 9:252-255. [PMID: 17989589 DOI: 10.1097/cnd.0b013e3181520095] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVE To report a series of patients with adult onset myotonic dystrophy type 1 (DM1) in whom the presenting symptom was ventilatory failure. BACKGROUND Ventilatory failure is a common complication of DM1 and may be a presenting symptom in the setting of anesthesia or surgery, but it is not known to be a heralding manifestation. METHOD Case series. RESULTS AND DISCUSSION Three adults developed dyspnea leading to ventilatory failure, with no cardiac or pulmonary causes identified. Case 1 required intubation for ventilator support and was sedated with propofol. There was no clinical myotonia, and electromyography (EMG) demonstrated brief runs of myotonic discharges. Examination 3 weeks later off propofol revealed percussion myotonia, and EMG evidence of long runs of myotonic discharges. Genetic testing confirmed the diagnosis of DM1. Case 2 had cataracts and ptosis but no known diagnosis of DM and no previous neurological impairments. Case 3 was previously neurologically asymptomatic but her son had congenital DM1. The diagnosis was confirmed by EMG in cases 2 and 3, and both patients were managed with bilevel ventilation (BIPAP). CONCLUSION Myotonic dystrophy type 1 should be considered in the differential diagnosis of acute ventilatory failure in adults.
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Affiliation(s)
- Nizar Souayah
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA.
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17
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Abstract
Myotonic dystrophy types 1 (DM1) and 2 (DM2) are similar yet distinct autosomal-dominant disorders characterized by muscle weakness, myotonia, cataracts, and multiple organ involvement, including the brain. One key difference between DM1 and DM2 is that a congenital form has been described for DM1 only. Expression of RNA transcripts containing pathogenic repeat lengths produces defects in alternative splicing of multiple RNAs, sequesters specific repeat-binding proteins, and ultimately leads to developmentally inappropriate splice products for a particular tissue. Whether brain pathology in its entirety in adult DM1 and DM2 is caused by interference in RNA processing remains to be determined. This review focuses on the similarities and differences between DM1 and DM2 with respect to neuropsychological, neuropathological, and neuroimaging data relating to cerebral involvement, with special emphasis on the clinical relevance and social consequences of such involvement.
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Affiliation(s)
- Giovanni Meola
- Department of Neurology, University of Milan, IRCCS Policlinico San Donato, San Donato Hospital, Via Morandi 30, 20097 San Donato Milanese, Milan, Italy.
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18
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Shahrizaila N, Kinnear WJM, Wills AJ. Respiratory involvement in inherited primary muscle conditions. J Neurol Neurosurg Psychiatry 2006; 77:1108-15. [PMID: 16980655 PMCID: PMC2077539 DOI: 10.1136/jnnp.2005.078881] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Patients with inherited muscle disorders can develop respiratory muscle weakness leading to ventilatory failure. Predicting the extent of respiratory involvement in the different types of inherited muscle disorders is important, as it allows clinicians to impart prognostic information and offers an opportunity for early interventional management strategies. The approach to respiratory assessment in patients with muscle disorders, the current knowledge of respiratory impairment in different muscle disorders and advice on the management of respiratory complications are summarised.
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Affiliation(s)
- N Shahrizaila
- Department of Neurology, Queen's Medical Centre, Nottingham NG7 2UH, UK
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20
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Talbot K, Stradling J, Crosby J, Hilton-Jones D. Reduction in excess daytime sleepiness by modafinil in patients with myotonic dystrophy. Neuromuscul Disord 2003; 13:357-64. [PMID: 12798791 DOI: 10.1016/s0960-8966(03)00030-0] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Patients with myotonic dystrophy frequently suffer from excess daytime sleepiness, which can be a significant cause of disability. Previous studies have indicated that this excess daytime sleepiness is only occasionally due to obstructive sleep apnoea and may be principally of central nervous system origin. Modafinil has been successfully used to treat narcolepsy, a central disorder causing excess daytime sleepiness. We have investigated the use of this drug in myotonic dystrophy patients with excess daytime sleepiness. Patients were recruited from a clinic population on the basis of screening with the Epworth Sleepiness Scale. Patients scoring 10 and above were invited to participate in a randomized double-blind crossover trial of modafinil versus placebo, with four weeks in each arm of the study separated by a 2-week washout period. Patients were assessed by polysomnography at baseline. The primary outcome measures were change in both the Epworth Sleepiness Scale and a modified Maintenance of Wakefulness Test, which were measured at the start of each arm of the trial and in week 3 of each intervention period. In agreement with previous smaller studies, sleepiness is not correlated with CTG expansion size. Treatment with modafinil showed a non-significant reduction in median Epworth Sleepiness Scale. However, the median Maintenance of Wakefulness Test score was prolonged by treatment (31.7-40 min, P=0.006). There were no significant adverse cardiac effects of the drug in this group of patients (resting 12 lead and 24 h ECG monitoring). Selected patients with myotonic dystrophy and excess daytime sleepiness may benefit from modafinil. In this patient group the Epworth Sleepiness Scale may not be the most reliable measure of sleepiness. Despite the potential for cardiac disease in these patients, the drug was well tolerated with no adverse effects.
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Affiliation(s)
- K Talbot
- Department of Clinical Neurology, University of Oxford, Radcliffe Infirmary, Woodstock Road, Oxford OX2 6HE, UK
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21
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Miyamoto T, Miyamoto M, Suga T, Aizawa C, Takekawa H, Hirata K. Methylphenidate hydrochloride for excessive daytime sleepiness in a patient with myotonic dystrophy. Psychiatry Clin Neurosci 2002; 56:271-2. [PMID: 12047591 DOI: 10.1046/j.1440-1819.2002.00965.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 28-year-old man with a history of myotonic dystrophy (MyD) is described. His progressively worsening excessive daytime sleepiness (EDS) was treated with methylphenidate hydrochloride. Polysomonography (PSG), the multiple sleep latency test (MSLT), middle latency-evoked response, and auditory event-related potentials were used to assess the cause of EDS. The PSG detected small numbers of central sleep apneic episodes. Mean sleep latency, which was determined by MSLT, increased from 5 min before treatment to 14 min after treatment. The Pa, P1, and N1 amplitudes at the Cz site increased after treatment, but P3 latency remained unchanged. These observations suggest that EDS and impairment of cognitive and information processing seen in a patient with MyD may be caused by a central nervous system disorder.
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Affiliation(s)
- Tomoyuki Miyamoto
- Department of Neurology, Dokkyo University School of Medicine, Shimotsuga, Tochigi, Japan.
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22
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Abstract
Pediatric neurologic diseases are often associated with different kinds of sleep disruption (mainly insomnia, less frequently hypersomnia or parasomnias). Due to the key-role of sleep for development, the effort to ameliorate sleep patterns in these children could have important prognostic benefits. Study of sleep architecture and organization in neurologic disorders could lead to a better comprehension of the pathogenesis and a better treatment of the disorders. This article focuses on the following specific neurologic diseases: nocturnal frontal lobe epilepsy and abnormal motor behaviors of epileptic origin, evaluating differential diagnosis with parasomnias; achondroplasia, confirming the crucial role of craniofacial deformity in determining sleep-disordered breathing; neuromuscular diseases, mainly Duchenne's muscular dystrophy and myotonic dystrophy; cerebral palsy, evaluating either the features of sleep architecture and the importance of the respiratory problems associated; headaches, confirming the strict relationships with sleep in terms of neurochemical and neurobehavioral substrates; and finally a review on the effectiveness of melatonin for sleep problems in children with neurologic syndromes and mental retardation, blindness, and epilepsy.
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Affiliation(s)
- M Zucconi
- Sleep Disorders Center, Department of Neurology, IRCCS H San Raffaele, Milano, Italy
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Giubilei F, Antonini G, Bastianello S, Morino S, Paolillo A, Fiorelli M, Ferretti C, Fieschi C. Excessive daytime sleepiness in myotonic dystrophy. J Neurol Sci 1999; 164:60-3. [PMID: 10385049 DOI: 10.1016/s0022-510x(99)00042-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The aim of the present study was to assess whether or not there is any correlation between magnetic resonance imaging (MRI) abnormalities and excessive daytime sleepiness (EDS) in a consecutive series of patients with myotonic dystrophy (MD). The influences of nocturnal breathing abnormalities and sleep morphology on EDS were also evaluated. Ten MD patients were studied by means of an all-night polysomnographic recording, the multiple sleep latency test (MSLT) and MRI. Diagnosis of MD was established on the basis of the clinical and electrophysiological evidence of myotonia as well as of the characteristic genetic pattern. No patient had respiratory failure. Polysomnography and MSLT were also evaluated in ten healthy age-matched controls under the same environmental conditions. The mean MSLT value was significantly lower in patients than in controls. Five of the ten patients were found to have pathological EDS. The quantitative sleep variables and the nocturnal apnoeas in these five patients were not significantly different from those of the patients without EDS. As two patients did not undergo MRI because of claustrophobia, the MRI data were considered in eight patients. Corpus callosum (CC) atrophy was detected in four patients, whereas three patients showed hyperintense areas in the white matter. No correlation was found between EDS and MRI indexes of subcortical atrophy as well as volume of the hyperintense areas. By contrast, a correlation was found between the MSLT value and the reduction in the anterior area of the CC. Our data suggest that CC atrophy might occur in MD patients, and that the size of the CC anterior area might be associated with EDS.
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Affiliation(s)
- F Giubilei
- Department of Neurological Sciences, University La Sapienza, Rome, Italy
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Bégin P, Mathieu J, Almirall J, Grassino A. Relationship between chronic hypercapnia and inspiratory-muscle weakness in myotonic dystrophy. Am J Respir Crit Care Med 1997; 156:133-9. [PMID: 9230737 DOI: 10.1164/ajrccm.156.1.9509041] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We studied 134 patients with Steinert's myotonic dystrophy (MD) in order to determine the prevalence of chronic hypercapnia, the level of muscle weakness and forced expiratory volume at which hypercapnic respiratory failure is likely to occur, and how clinical assessment might help predict hypercapnic respiratory failure. Subjects were divided into five classes with a muscular disability rating scale (MDRS): 0 = no clinical impairment (n = 9), I = minimal signs of impairment (n = 11), II = distal weakness (n = 41), III = moderate proximal weakness (n = 62), and IV = nonambulatory (n = 11). The prevalence of hypercapnia (PaCO2 > or = 43 mm Hg) was found to be 0%, 27%, 29%, 45% and 55% for MDRS 0 to 4, respectively (p = 0.03). A multiple regression analysis limited to clinical data showed that daytime hypersomnolence was a significant cofactor with the MDRS (p = 0.01) in predicting PaCO2 (r = 0.40). Among respiratory parameters, FVC, respiratory muscle strength (RMS), and maximal inspiratory pressure against occluded airways (PImax) were found to be predictors of nearly equal strength, explaining 16%, 15%, and 14% of the PaCO2 variance, respectively. In multiple regression analysis, sex, daytime sleepiness, and the expected/observed FVC ratio for a given RMS were found to be significant cofactors with PImax in predicting PaCO2 (r = 0.51). It is concluded that respiratory insufficiency should be suspected in MD patients with proximal weakness or daytime sleepiness. The likelihood of hypercapnia also increases with volume restriction and respiratory muscle weakness. Our study suggests that the combination of inspiratory muscle weakness and loading plays a predominant role in the pathogenesis of chronic alveolar hypoventilation in MD patients. The occurrence of daytime hypersomnolence suggests that other factors, such as low central ventilatory drive or sleep apnea, might play an additional role.
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Affiliation(s)
- P Bégin
- Department of Medicine, University of Montréal, Québec, Canada
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Antonini G, Morino S, Fiorelli M, Fiorini M, Giubilei F. Selegiline in the treatment of hypersomnolence in myotonic dystrophy: a pilot study. J Neurol Sci 1997; 147:167-9. [PMID: 9106123 DOI: 10.1016/s0022-510x(96)05328-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Patients with myotonic dystrophy frequently complain of hypersomnolence, a symptom which seriously restricts their social life. The pathogenesis of this symptom is a matter of debate: it has been attributed to both alveolar hypoventilation and pathological changes in the brainstem. As selegiline has been shown to reduce the number of sleep attacks in nacrolepsy, we tested whether hypersomnolence in myotonic dystrophy would respond to the same treatment. Ten patients with myotonic dystrophy received selegiline/placebo (20 mg daily) in a double-blind crossover trial. We monitored daytime sleepiness by means of a multiple sleep latency test. Treatment appeared to be well tolerated but did not alter hypersomnolence in myotonic dystrophy. Further studies to assess the effect of higher doses of selegiline are warranted.
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Affiliation(s)
- G Antonini
- Dipartimento di Scienze Neurologiche, Università di Roma La Sapienza, Italy
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Di Costanzo A, Toriello A, Mottola A, Di Iorio G, Bonavita V, Tedeschi G. Relative sparing of extraocular muscles in myotonic dystrophy: an electrooculographic study. Acta Neurol Scand 1997; 95:158-63. [PMID: 9088384 DOI: 10.1111/j.1600-0404.1997.tb00088.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We studied 40 patients with myotonic dystrophy (MD) to investigate whether saccadic eye movement (SEM) abnormalities have a central or peripheral origin. SEMs were recorded by electrooculography and analyzed by a computer system. Six patients were followed up to 2-7 years. Slow SEMs were present in 70% of patients, while saccadic latency and accuracy were within normal ranges. Peak saccadic velocity (PSV) did not correlate with disease duration and muscular disability, and showed a significant reduction only in 1 patient during the follow-up. Muscular disability correlated significantly with age and disease duration and worsened in 4 patients over time. The doll's head maneuver elicited vestibular compensatory eye movements with high velocities. These findings suggest that the extraocular muscles are at least partially spared in MD and that supranuclear structures, most likely the burst cells in brainstem reticular formation, may contribute to the slowing of SEMs.
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Affiliation(s)
- A Di Costanzo
- Institute of Neurological Sciences, Faculty of Medicine, Second University of Naples, Italy
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