title: Factors associated with the effect of pramipexole on symptoms of idiopathic REM sleep behavior disorder.
abstract: BACKGROUND
  The clinical effectiveness of pramipexole (PPX), a candidate treatment for idiopathic rapid eye movement sleep behavior disorder (iRBD), varies among individuals. This study investigates factors associated with PPX effectiveness for treating RBD symptoms.
  
  
  METHODS
  Ninety-eight consecutive patients with RBD who had taken PPX or clonazepam (CNZP) for more than three months were enrolled. Factors associated with PPX effectiveness were examined: the ratio of REM sleep without atonia to total REM sleep (RWA/REM), length of RBD morbidity, frequency of vocalization or abnormal behavior, and Sniffin' Stick Test scores. These factors were also compared among the responders to PPX monotherapy, CNZP monotherapy, and PPX + CNZP combined therapy.
  
  
  RESULTS
  PPX was efficacious in 61.7% (50/81) of the subject patients. RWA/REM was associated with PPX effectiveness. The cut-off rate of RWA/REM for predicting PPX effectiveness was estimated as 16.8%. Responders to PPX + CNZP combined therapy showed significantly higher RWA/REM and frequency of vocalization or dream enactment behavior than either responders to monotherapy with PPX or to CNZP.
  
  
  CONCLUSIONS
  PPX is probably applicable as an alternative to CNZP, especially for mild iRBD cases with a lower rate of RWA. Results of this study suggest that dopaminergic dysfunction can play a role in iRBD pathophysiology.
authors.affiliation: Japan Somnology Center, Neuropsychiatric Research Institute, Tokyo, Japan. taeko_ssi@yahoo.co.jp
authors.forename: Taeko
authors.initials: T
authors.lastname: Sasai
authors.forename: Masato
authors.initials: M
authors.lastname: Matsuura
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Inoue
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D052160:Benzothiazoles / Q000627:therapeutic use*; D002998:Clonazepam / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077487:Pramipexole; D020187:REM Sleep Behavior Disorder / Q000188:drug therapy*
chemical_list: D000978:Antiparkinson Agents; D052160:Benzothiazoles; D002998:Clonazepam; D000077487:Pramipexole