title: Daytime sleepiness, sleep disturbance and functioning impairment in bipolar disorder.
abstract: OBJECTIVE
  To verify the prevalence and clinical impact of excessive daytime sleepiness (EDS) in outpatients with bipolar disorder.
  
  
  METHODS
  Eighty-one outpatients with bipolar disorder and 79 healthy control subjects were recruited. Patients were required not to be acutely manic or depressed. We used the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index and the Functioning Assessment Short Test to assess sleepiness, sleep problems and functioning, respectively.
  
  
  RESULTS
  Patients had a higher prevalence of sleepiness (40%) than the control group (18%). Sleepiness and sleep disturbance had independent impacts on disability in the multivariable model.
  
  
  CONCLUSIONS
  This study suggests that EDS is a relevant clinical dimension in patients with bipolar disorder. It is a frequent symptom that often overlaps with other sleep disturbances. This study also reveals that once present it has the potential to increase functional impairment.
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Julio C
authors.initials: JC
authors.lastname: Walz
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Pedro V
authors.initials: PV
authors.lastname: Magalhães
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Ramiro
authors.initials: R
authors.lastname: Reckziegel
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Monise
authors.initials: M
authors.lastname: Costanzi
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Larriany
authors.initials: L
authors.lastname: Giglio
authors.affiliation: 1 Bipolar Disorders Program & INCT Translational Medicine, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Flávio
authors.initials: F
authors.lastname: Kapczinski