Sleep disorders and neuromuscular disease.

Breathing is the most important executive function of sleep. Compromise of the ventilatory mechanism is the principal consequence of a neuromuscular dysfunction in the individual who is asleep. This includes alterations of the lower motor neuron, the neuromuscular junction, and muscle. The primordial phenomenon in rapid eye movement (REM) sleep respiratory physiology is that the diaphragm assumes all functions of respiration. Any dysfunction of the diaphragm, whether neurogenic or neuromuscular, will interfere with breathing during REM sleep. So prevalent are sleep respiratory difficulties in patients with neuromuscular disorders that there should be a low threshold to obtain nocturnal polysomnography in these patients with sleep complaints. In patients with a neuromuscular disorder and nocturnal ventilatory compromise, positive airway pressure ventilation improves the quality of sleep and in doing so improves the overall quality of life.