Use of pramipexole in REM sleep behavior disorder: results from a case series.

BACKGROUND AND PURPOSE Rapid eye movement (REM) sleep behavior disorder (RBD) has a known association with other medical conditions, including narcolepsy and neurodegenerative diseases such as synuclienopathies. RBD is currently treated with clonazepam as a first-line therapy. Recent research suggests that the pathophysiology underlying RBD may involve a dopaminergic deficiency, given its association with Parkinson syndromes and restless legs syndrome (RLS). We report on the efficacy of pramipexole, a dopaminergic D2-3 receptor agonist, in the treatment of RBD. PATIENTS AND METHODS The first 10 consecutive patients presenting with a history and polysomnographically confirmed RBD were given pramipexole as either a single dose before bedtime or as a divided dose regimen with the first dose given in the early evening and the second dose at bedtime. Medication was titrated to control RBD symptoms and the clinical response was monitored through interviews with the patient, spouse, and close family members during the course of the study at regularly scheduled follow-up visits. RESULTS The mean length of treatment was 13.1 months, and the average total evening dose of pramipexole at the end of the study was 0.89+/-0.31 mg. A divided dose regimen of pramipexole was used in 56% of patients remaining on pramipexole. We found that 89% of patients experienced either a moderate reduction or complete resolution in the frequency of RBD symptoms throughout the duration of the study. Moreover, 67% reported at least a moderate reduction in the severity of remaining symptoms. CONCLUSIONS Pramipexole markedly reduced the frequency and severity of RBD symptoms and appeared to maintain efficacy for up to 25 months as assessed at follow-up visits. Clonazepam may have numerous unwanted side effects in the elderly or narcoleptics with RBD, such as prominent sedation and the potential exacerbation of underlying obstructive breathing in sleep. The potential role of pramipexole in improving RBD and its associated dopamine deficient syndromes warrants further research in the use of dopaminergic agonists as a potential first-line alternative therapy for RBD.