Group comparison of demographic, clinical and polysomnographic characteristics, 1) between PD patients with and without SDB, and 2) between PD patients with SDB and control subjects with SDB.

BMI: body mass index; Co-SDB: controls with sleep-disordered breathing; ESS: Epworth Sleepiness Scale;NREM: non-REM; PD-SDB: Parkinson’s disease patients with sleep-disordered breathing; PD-wo: Parkinson’s disease patients without sleep-disordered breathing; REM: rapid eye movement; SaO2: oxygen saturation; SWS: slow wave sleep; SAS-SDQ: Sleep Apnea scale of the Sleep Disorders Questionnaire; UPDRS: Unified Parkinson’s Disease Rating Scale.