title: Sleep disturbances in myotonic dystrophy type 2.
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.
authors.affiliation: 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.
authors.forename: Paul
authors.initials: P
authors.lastname: Shepard
authors.forename: Erek M
authors.initials: EM
authors.lastname: Lam
authors.forename: Erik K
authors.initials: EK
authors.lastname: St Louis
authors.forename: Jacob
authors.initials: J
authors.lastname: Dominik
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000503:physiopathology*; D005221:Fatigue / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020967:Myotonic Disorders / Q000150:complications* / Q000503:physiopathology; D009223:Myotonic Dystrophy; D011446:Prospective Studies; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000209:etiology*