Characteristics of obstructive sleep apnea in patients with Parkinson's disease.

Parkinson's disease (PD) patients frequently develop obstructive sleep apnea (OSA). In order to clarify the clinical significance of OSA in PD, we compared descriptive variables between PD patients with OSA (PD+OSA) and without (PD-OSA), and between the PD+OSA group and a group of OSA patients without PD (control OSA). The apnea hypopnea index (AHI) cutoff of 15 episodes/hour on polysomnogram (PSG) was used to assign 107 PD patients to groups; OSA-related symptoms and PSG findings were then compared. Demographic and PSG variables were compared between PD+OSA patients and 31 OSA controls. Twenty-four patients with PD (22.4%) were classified as PD+OSA. There were no significant differences in descriptive variables between the PD+OSA and PD-OSA groups. The PD+OSA group had a higher arousal index on PSG than the PD-OSA group, although the two groups had similar ESS scores. The PD+OSA patients had a lower respiratory arousal index and a smaller decrease in oxygen saturation than the control OSA group, despite having a similar AHI. The prevalence of OSA in PD did not differ from that in the general elderly population, indicating that the clinical significance of OSA as a contributor to daytime sleepiness in PD is low.