Sleep disordered breathing in Parkinson's disease: Assessing the relevance of REM behavior sleep disorder and hypoxic...

The effects of sleep disordered breathing (SDB) in Parkinson's Disease (PD) are poorly understood. Data is uncertain regarding correlation with REM sleep behavior disorder (RBD) and the effects on non-motor symptoms. Markers of hypoxic burden other than the Apnea-Hypopnea Index (AHI) have been overlooked. We aimed to assess the relation between SDB, RBD and non-motor symptoms in PD patients.

71 PD patients (29 with RBD) were compared with healthy controls matched for sex, age and AHI, regarding video-PSG data, including obstructive AHI (total, REM and NREM), Mean O₂ Saturation %, number of O² desaturations >4 % (NuO₂des), Minimal O₂ desaturation (MinO₂des), O₂ Desaturation Index and % of time with O₂ Saturation <90 %. 32 patients were also assessed for non-motor symptoms.

PD patients presented significantly lower sleep efficiency (SE), REM sleep duration and AHI in REM and higher MinO₂des. These findings were replicated on RBD patients when compared with their respective controls but not on non-RBD patients (except for lower SE). There was a very significant association between the NuO₂des and cardiovascular symptoms; hallucinations were significantly associated with NREM AHI and very significantly associated with MinO₂des.

Compared to subjects with same AHI, PD patients showed lower SE, lower AHI during REM sleep and less O₂ desaturation. These differences were related to the presence of RBD, suggesting a protective role of REM sleep without atonia. SDB, and particularly O₂ desaturation markers, bear a significant association with cardiovascular symptoms and hallucinations.