Characteristics of sleep dysfunction and sleep - disordered breathing in amyotrophic lateral sclerosis patients

Objective To study the characteristics of sleep architecture and sleep - disordered breathing (SDB) in patients with amyotrophic lateral sclerosis (ALS) using polysomnography (PSG). Methods A total of 36 patients with ALS were recruited in this study. According to symptoms of medulla oblongata, the patients were divided into limb involvement group (N = 14) and bulbar palsy group (N = 22). Detailed record of the patients was made including general information and chief complaints of sleep dysfunction and SDB, which covered sleep initiation and maintenance disorders, arousals, difficulty in breathing and snoring, nocturnal polyuria, restless legs syndrome (RLS) and muscle soreness. Appel Amyotrophic Lateral Sclerosis (AALS) Scores were used to assess bulbar function, breathing function,myodynamia and limbs function. PSG was performed to monitor EEG, EOG, EMG, ECG, position, snore, gas flow of mouth and nose, chest breathing, pulse oxygen saturation (SpO 2 ) and sleep-related parameters including total sleep time (TST), sleep efficiency (SE), sleep latency (SL), awakening times, percentage of different non-rapid eye movement (NREM) and rapial eye movement (REM), and apnea hypopnea index (AHI). Pearson correlation analysis evaluated the relationship between AHI of REM, periodic limb movements (PLM) and clinical information, AALS Scores. Results Bulbar palsy group had higher scores in AALS Scores ( P = 0.007), bulbar function ( P = 0.000) and breathing function ( P = 0.000), and lower score in upper limb myodynamia ( P = 0.016) than limb involvement group. Both 2 groups showed disturbed sleep architecture in the performance of sleep fragmentation. Bulbar palsy group had more awakening times ( P = 0.027), lower percentage of REM sleep ( P = 0.009) and less PLM ( P = 0.020) than limb involvement group. The main respiratory event of 2 groups was hypopnea. Bulbar palsy group had higher AHI (P = 0.038) and AHI of REM and NREM ( P = 0.031, 0.049) than limb involvement group. Pearson correlation analysis showed that AHI of REM was positively correlated with duration ( r = 0.654, P = 0.028), AALS total score ( r = 0.458, P = 0.034), bulbar function score ( r = 0.572, P = 0.030) and breathing function ( r = 0.756, P = 0.002). PLM was also positively correlated with duration ( r = 0.574, P = 0.030), AALS total score ( r = 0.321, P = 0.042), upper limb function ( r = 0.656, P = 0.028) and lower limb function ( r = 0.754, P = 0.015). Conclusions Patients with ALS have many types of sleep disorders including insomnia, SDB and periodic limb movements disorder (PLMD). PSG can monitor respiratory event thus providing clinical evidence for the non-invasive ventilation intervention. DOI: 10.3969/j.issn.1672-6731.2017.10.007