Sleep and breathing in neuromuscular disorders

This chapter gives an overview of the control of breathing during sleep and wakefulness in normal individuals, its alteration in various neuromuscular disorders, types of sleep-disordered breathing (SDB), mechanism and pathogenesis of respiratory failure in neuromuscular diseases, clinical features including impact on breathing during sleep causing SDB and sleep dysfunction, and an approach to patients with suspicion of SDB, laboratory techniques and principles of treatment. Neuromuscular disorders traditionally include all diseases caused by dysfunction of the motor units. Sleep dysfunction related mostly to SDB is very common in neuromuscular diseases, particularly in the advanced stage, but occasionally occurs as a presenting symptom. The most common neuromuscular disorders causing SDB and sleep dysfunction consist of: motor neuron disease, poliomyelitis and postpolio syndrome, myasthenia gravis including myasthenic syndrome, acute inflammatory demyelinating polyradiculoneuropathy, phrenic neuropathy, muscular dystrophies including myotonic dystrophies, and congenital myopathies. Many of these conditions are treatable whereas others show relentless progression of the disease, but even in those conditions quality of life may be improved with prolongation of the natural course of the illness by timely and adequate treatment of SDB.