title: Sleep disorders in spinocerebellar ataxia type 2 patients.
abstract: BACKGROUND
  Sleep disturbances are common features in spinocerebellar ataxias (SCAs). Nevertheless, sleep data on SCA2 come from scarce studies including few patients, limiting the evaluation of the prevalence and determinants of sleep disorders.
  
  
  OBJECTIVE
  To assess the frequency and possible determinants of sleep disorders in the large and homogeneous SCA2 Cuban population.
  
  
  METHODS
  Thirty-two SCA2 patients and their age- and sex-matched controls were studied by video-polysomnography and sleep interviews.
  
  
  RESULTS
  The most striking video-polysomnography features were rapid eye movement (REM) sleep pathology and periodic leg movements (PLMs). REM sleep abnormalities included a consistent reduction of the REM sleep percentage and REM density as well as an increase in REM sleep without atonia (RWA). REM sleep and REM density decreases were closely related to the increase in ataxia scores, whereas the RWA percentage was influenced by the cytosine-adenine-guanine (CAG) repeats. PLMs were observed in 37.5% of cases. The PLM index showed a significant association with the ataxia score and disease duration but not with CAG repeats.
  
  
  CONCLUSIONS
  REM sleep pathology and PLMs are closely related to SCA2 severity, suggesting their usefulness as disease progression markers. The RWA percentage is influenced by the CAG repeats and might thus be a sensitive parameter for reflecting polyglutamine toxicity. Finally, as PLMs are sensible to drug treatment, they represents a new therapeutic target for the symptomatic treatment of SCA2.
authors.affiliation: Centre for the Research and Rehabilitation of Hereditary Ataxias, Holguín, Cuba.
authors.forename: Luis
authors.initials: L
authors.lastname: Velázquez-Pérez
authors.forename: Ursula
authors.initials: U
authors.lastname: Voss
authors.forename: Roberto
authors.initials: R
authors.lastname: Rodríguez-Labrada
authors.forename: Georg
authors.initials: G
authors.lastname: Auburger
authors.forename: Nalia
authors.initials: N
authors.lastname: Canales Ochoa
authors.forename: Gilberto
authors.initials: G
authors.lastname: Sánchez Cruz
authors.forename: Lourdes
authors.initials: L
authors.lastname: Galicia Polo
authors.forename: Reyes
authors.initials: R
authors.lastname: Haro Valencia
authors.forename: Raúl
authors.initials: R
authors.lastname: Aguilera Rodríguez
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Medrano Montero
authors.forename: Jose M
authors.initials: JM
authors.lastname: Laffita Mesa
authors.forename: Inka
authors.initials: I
authors.lastname: Tuin
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D004247:DNA / Q000235:genetics; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D010641:Phenotype; D017286:Polysomnography; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012893:Sleep Wake Disorders / Q000209:etiology*; D012895:Sleep, REM / Q000502:physiology; D020754:Spinocerebellar Ataxias / Q000150:complications* / Q000235:genetics; D019680:Trinucleotide Repeat Expansion; D055815:Young Adult
chemical_list: D015415:Biomarkers; D004247:DNA