title: Development of excessive daytime sleepiness in early Parkinson disease.
abstract: OBJECTIVE
  To examine the frequency, development, and risk factors of excessive daytime sleepiness (EDS) in a cohort of originally drug-naive patients with incident Parkinson disease (PD) during the first 5 years after diagnosis.
  
  
  METHODS
  One hundred fifty-three drug-naive patients with early PD derived from a population-based incident cohort and 169 control participants were assessed for EDS and reevaluated after 1, 3, and 5 years on medication. EDS was diagnosed according to the Epworth Sleepiness Scale. Cutoff score above 10 was applied. Generalized estimating equation models for correlated data were used to examine associated and risk factors for EDS.
  
  
  RESULTS
  Patients reported EDS more often than control participants at the time of diagnosis and during follow-up. The frequency of EDS in PD increased from 11.8% at baseline to 23.4% after 5 years. Associated factors were male sex, the use of dopamine agonists, and higher Montgomery-Åsberg Depression Rating Scale and Unified Parkinson's Disease Rating Scale-activities of daily living scores. Main risk factor for developing EDS was an increased Epworth Sleepiness Scale score at baseline.
  
  
  CONCLUSIONS
  EDS is more frequent in PD even before treatment initiation compared with control participants and increases in occurrence with disease progression. The main risk factor for developing EDS with time is an early predisposition for sleepiness. In addition, the use of dopamine agonists was associated with the development of EDS. These findings necessitate caution in patients with PD and early increased sleep propensity and when using dopamine agonists.
authors.affiliation: From The Norwegian Centre for Movement Disorders (L.K.T., J.P.L., J.S., M.D.G.), Stavanger; Department of Neurology (L.K.T., M.D.G.), Stavanger University Hospital; and Department of Neurology (O-B.T.), Haukeland University Hospital, Bergen, Norway.
authors.forename: Lena K
authors.initials: LK
authors.lastname: Tholfsen
authors.affiliation: From The Norwegian Centre for Movement Disorders (L.K.T., J.P.L., J.S., M.D.G.), Stavanger; Department of Neurology (L.K.T., M.D.G.), Stavanger University Hospital; and Department of Neurology (O-B.T.), Haukeland University Hospital, Bergen, Norway.
authors.forename: Jan P
authors.initials: JP
authors.lastname: Larsen
authors.affiliation: From The Norwegian Centre for Movement Disorders (L.K.T., J.P.L., J.S., M.D.G.), Stavanger; Department of Neurology (L.K.T., M.D.G.), Stavanger University Hospital; and Department of Neurology (O-B.T.), Haukeland University Hospital, Bergen, Norway.
authors.forename: Jörn
authors.initials: J
authors.lastname: Schulz
authors.affiliation: From The Norwegian Centre for Movement Disorders (L.K.T., J.P.L., J.S., M.D.G.), Stavanger; Department of Neurology (L.K.T., M.D.G.), Stavanger University Hospital; and Department of Neurology (O-B.T.), Haukeland University Hospital, Bergen, Norway.
authors.forename: Ole-Bjorn
authors.initials: OB
authors.lastname: Tysnes
authors.affiliation: From The Norwegian Centre for Movement Disorders (L.K.T., J.P.L., J.S., M.D.G.), Stavanger; Department of Neurology (L.K.T., M.D.G.), Stavanger University Hospital; and Department of Neurology (O-B.T.), Haukeland University Hospital, Bergen, Norway. gjmi@sus.no.
authors.forename: Michaela D
authors.initials: MD
authors.lastname: Gjerstad
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000009:adverse effects*; D015331:Cohort Studies; D006970:Disorders of Excessive Somnolence / Q000209:etiology*; D018491:Dopamine Agonists / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000188:drug therapy*
chemical_list: D000978:Antiparkinson Agents; D018491:Dopamine Agonists