REM sleep behavior disorder in patients with Parkinson's disease: clinical and polysomnographic characteristics

The objectives of this study were to describe the characteristics of RBD in a group of PD patients and verify the accuracy of the clinical interview in this group, determine the causes of failure of the interview, as well as to verify the clinical and polysomnographic differences between the groups of PD patients with and without RBD. So, a cross-sectional study was conducted in 88 consecutive PD patients from the outpatient clinic, during a period of 21months. Participants underwent a clinical interview, assessment based on standardized scales (Epworth Sleepiness Scale, Parkinson's disease Questionnaire, Pittsburgh Sleep Quality Index), and video polysomnography. Out of the 88 participants, 55 underwent vPSG which confirmed a diagnosis of RBD. The clinical interview had a high sensitivity (87.5%) but a low specificity (42.1%) for RBD diagnosis and thus the clinical interview alone may miss those without episodes of dream-enacting behavior. We note in this group a higher proportion of men (54.5%) and an average age of 60.4years +/- 10.6. In 54% of patients, RBD preceded motor symptoms of PD. In addition, patients with PD and RBD had lower Apnea-Hypopnea Index in REM sleep and a higher equivalent dose of levodopa than PD patients without RBD. RBD is a prevalent condition in patients with PD, requiring polysomnography for diagnostic confirmation, and is associated with certain particularities in PD.