Breathing problems include an increased susceptibility to chest infections, difficulty coughing and clearing phlegm, breathlessness, and under-breathing (known as hypoventilation) particularly during sleep. This factsheet provides background information on how families can help in the management of respiratory problems and identify symptoms which require investigation.
Who develops breathing problems, and at what age?
Respiratory muscle weakness is relatively common in most neuromuscular conditions and is inevitable in the late stages of Duchenne muscular dystrophy. The age at which respiratory problems develop varies enormously in different conditions. Breathing difficulties can arise shortly after birth in children with severe Type 1 spinal muscular atrophy and during the first few months of life in some other myopathies. Individuals with congenital muscular dystrophy or Type 2 spinal muscular atrophy may run into breathing problems in childhood. Young men with Duchenne muscular dystrophy tend to develop symptoms of nocturnal hypoventilation aged 15-20 years, and respiratory muscle involvement in conditions such as limb girdle muscular dystrophy and acid maltase deficiency may not occur until adulthood.
Respiratory muscle strength can be very variable within and between neuromuscular disorders, therefore investigations and treatment must be tailored to the individual. Long-term management of breathing problems should always be medically supervised.
Recent research (Neuromuscular Disorders November 2002) shown that non-invasive nocturnal ventilation can have a significant effect on extending the life span of children with Duchenne muscular dystrophy (DMD). Overall, better co-ordinated care has probably improved the chances of survival to 25 years from 0% in the 60s to 4% in the 70s and 12% in the 80s. Nocturnal ventilation has increased this possibility to 53% in the 1990s, and these figures are continuing to improve all the time.