Excessive fragmentary myoclonus in Machado–Joseph disease

• Published in: Sleep medicine Vol. 15; no. 3; pp. 355 - 358
• Main Authors: dos Santos, Diogo Fernandes, Pedroso, José Luiz, Braga-Neto, Pedro, Silva, Giselle Melo Fontes, de Carvalho, Luciane Bizari Coin, Prado, Lucila B.F, Barsottini, Orlando Graziani P, do Prado, Gilmar Fernandes
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2014
• Subjects: Adult; Case-Control Studies; Excessive fragmentary myoclonus; Female; Humans; Machado-Joseph Disease - complications; Machado–Joseph disease; Male; Middle Aged; Neurology; Nocturnal Myoclonus Syndrome - etiology; Nocturnal Myoclonus Syndrome - physiopathology; Nonmotor symptoms; Polysomnography; Risk Factors; Sleep - physiology; Sleep disorders; Sleep Medicine; Spinocerebellar ataxia; Excessive fragmentary myoclonus; Sleep disorders; Nonmotor symptoms; Polysomnography; Spinocerebellar ataxia; Machado–Joseph disease
• ISSN: 1389-9457; 1878-5506
• DOI: 10.1016/j.sleep.2013.09.025

Abstract Objective Machado–Joseph disease (MJD) is a neurodegenerative disease which usually presents several clinical findings including cerebellar ataxia and other extracerebellar features, such as Parkinsonism, dystonia, peripheral neuropathy, and lower motor neuron disease. Some data have demonstrated a high frequency of sleep disorders in these patients, including excessive daytime sleepiness (EDS), insomnia, obstructive sleep apnea (OSA), rapid eye movement (REM) sleep behavior disorder (RBD), and restless legs syndrome (RLS). Herein, we aimed to describe the high frequency of excessive fragmentary myoclonus (EFM) in MJD. Materials and methods We recruited 44 patients with MJD and 44 healthy controls. All participants underwent an all-night polysomnography (PSG). EFM was evaluated and defined in accordance to the criteria of the American Academy of Sleep Medicine. Results Half of the MJD patients ( n = 22) had EFM diagnosed through PSG, though no healthy control participant presented this finding ( P < .0001). In the MJD group, older participants and men had a higher frequency of EFM. There was no correlation between EFM and the following data: body mass index (BMI), apnea–hypopnea index (AHI), EDS, loss of atonia during REM sleep, periodic limb movements during sleep (PLMS), RLS, RBD, ataxia severity, the number of cytosine–adenine–guanine trinucleotide (CAG) repeats, disease duration, sleep efficiency, sleep fragmentation, and sleep stage percentages between patients with or without EFM. Conclusion EFM is highly prevalent in patients with MJD. Our study demonstrates that EFM must be included in the clinical spectrum of sleep disorders in MJD patients.