Sleep disorders in neuromuscular diseases

Abstract

Patients with neuromuscular disorders (NMD) are especially vulnerable to sleep-related dysfunction. Sleep-disordered breathing often precedes diurnal respiratory failure in NMD patients, requiring timely recognition and management with noninvasive ventilation (NIV). This paper reviews the mechanisms, diagnostic evaluation, and management of sleep disorders in various neuromuscular diseases. The severity, duration, and type of NMD influence the pattern of sleep disturbance. Several investigators have addressed other clinical aspects including rating scales for sleep complaints, hypocretin-1 deficiency, excessive daytime somnolence, and relation of sleep disorder with length of CTG trinucleotide repeats in myotonic dystrophy. Benefits of NIV on quality of life and survival in adults and children with chronic NMD are well established, and recently have been documented even in patients with nocturnal hypoventilation and daytime normocapnia. In contrast, the timing for investigation with polysomnography and for initiation of NIV is debated. Patients with chronic NMD should be routinely assessed for sleep-disordered breathing and sleep complaints, because these are treatable complications in an otherwise progressive disease process. Further research is needed to establish the indications for polysomnography and to determine the optimal timing for initiating NIV to treat sleep-disordered breathing in patients with neuromuscular diseases.