Children with neuromuscular problems like Duchenne’s muscular dystrophy or DMD, Spino-muscular atrophy or SMA, congenital myopathies and other muscular dystrophies develop difficulty in breathing during sleep.

Why do children with neuromuscular problems develop breathing difficulty during sleep?

Children with neuromuscular problems have weakness in the various groups of muscles in the body. This weakness also involves the muscles of the chest and hence leading to difficulty in breathing. During sleep the  body muscles relax called hypotonia, which is more marked during REM sleep or dream sleep. Hence, breathing gets difficult during sleep, especially REM sleep or dream sleep.

What are the problems that happen during sleep in children with neuromuscular problems?

Breathing problems in sleep can occur such as pauses in breathing (sleep apneas) and shallow breathing (hypoventilation) leading to accumulation of carbon dioxide (waste gas) in the body. The apneas can sometimes be observed by parents or caregivers. As these apneas happen mostly in REM sleep they sometimes may not be observed. Sleep apnea and hypoventilation in children with neuromuscular disorders lead to frequent awakenings during sleep (arousals) and a disturbed sleep (sleep fragmentation).

Children with neuromuscular disorders having sleep apnea and hypoventilation can have headaches in the morning, due to accumulation of carbon dioxide in the body. They might feel dull, tired and sleepy during the day. Sleep apnea and hypoventilation also leads to frequent chest infections.

When should sleep problems be suspected in children with neuromuscular problems?

These are a few indicators suggesting sleep apnea and hypoventilation in children with neuromuscular problems. Remember that many children with neuromuscular problems may not have clear symptoms.

• Children with neuromuscular problems usually have sleep apnea and hypoventilation once they develop difficulty in walking. Hence, children who are non-ambulatory need to be evaluated for sleep apnea and hypoventilation.
• Children with neuromuscular problems should get a spirometry every 6-12 months. Children with restriction in spirometry should be evaluated for sleep apnea and hypoventilation.
• Children with neuromuscular problems having recurrent chest infections should be evaluated for sleep apnea and hypoventilation.
• Children with neuromuscular problems having any night-time problems such as pause in breathing, gasping or daytime symptoms such as headaches and tiredness should be evaluated for sleep apnea and hypoventilation.

What investigations are required in children with neuromuscular problems suspected to have sleep apnea and hypoventilation?

Children with neuromuscular problems suspected to have sleep apnea and hypoventilation require a sleep study or polysomnography for proper diagnosis. Sleep study gives detailed information on a child’s breathing pattern during sleep, any apneas (cessation in breathing), hypoventilation (shallow breathing), and retention of carbon dioxide (waste gas). For more information on sleep study visit our page on Pediatric Sleep Studies.