Respiratory and Sleep Problems in Children with Duchenne Muscular Dystrophy

Respiratory and Sleep Problems in Children with Duchenne Muscular Dystrophy

Duchenne Muscular Dystrophy (DMD) is a progressive neuromuscular condition that primarily affects boys and leads to gradual weakening of the skeletal muscles, including those responsible for breathing. As the condition advances, it can cause serious respiratory and sleep problems, particularly during the night. Sleep disordered breathing and night-time respiratory failure are significant concerns in children with  Duchenne Muscular Dystrophy (DMD)  and require timely diagnosis and intervention—most importantly through pulmonary function tests, sleep studies, and appropriate use of BiPAP support.

Why Do Children with Duchenne Muscular Dystrophy (DMD) Develop Sleep Problems?

As Duchenne Muscular Dystrophy (DMD) progresses, the respiratory muscles—including the diaphragm and intercostal muscles—become weaker. During sleep, especially during REM sleep, these weakened muscles are unable to maintain normal breathing patterns. This results in hypoventilation, where breathing becomes too shallow, leading to low oxygen and high carbon dioxide levels during the night.

Initially, breathing difficulties are only present during sleep, but without proper monitoring and support, this may progress to daytime respiratory issues.

Night-Time Respiratory Failure in Duchenne Muscular Dystrophy (DMD)

Night-time respiratory failure often starts with subtle symptoms that are easily overlooked. Common signs include:

• Restless or disturbed sleep

• Loud snoring or pauses in breathing (apnea)

• Early morning headaches

• Excessive daytime sleepiness

• Night sweats

• Poor concentration and fatigue

These are indicators of sleep disordered breathing and potential nocturnal hypoventilation, which can be detected early through appropriate evaluation.

Role of Pulmonary Function Tests (PFTs)

Regular pulmonary function testing (PFT) is critical in monitoring the progression of respiratory muscle weakness in children with Duchenne Muscular Dystrophy. Spirometry and other lung function assessments can help detect early declines in lung capacity and respiratory strength, even before symptoms appear.

Key benefits of regular PFTs include:

• Tracking the decline in respiratory function over time

• Identifying the right time to perform a sleep study

• Helping in the early initiation of non-invasive ventilation like BiPAP

• Guiding the overall respiratory management plan

It is generally recommended to start annual PFTs by age 6–7 or earlier if symptoms develop. As the disease progresses, more frequent testing (every 6 months) may be advised.

Role of Sleep Study in Diagnosing Sleep Disordered Breathing

A polysomnography (sleep study) is essential in diagnosing sleep disordered breathing in Duchenne Muscular Dystrophy (DMD)

. It helps evaluate:

• Oxygen levels

• Carbon dioxide retention (capnography)

• Apnea and hypopnea episodes

• Breathing effort

• Sleep quality

Detecting nocturnal hypoventilation or apneas early allows timely intervention to prevent further respiratory decline.

Use of BiPAP in Duchenne Muscular Dystrophy

When nocturnal hypoventilation or respiratory distress is detected, BiPAP (Bilevel Positive Airway Pressure) is the preferred non-invasive ventilation strategy. It provides two levels of pressure—higher during inhalation and lower during exhalation—which supports weak respiratory muscles more effectively than CPAP.

Benefits of BiPAP therapy:

• Supports ventilation during sleep

• Improves oxygenation and removes excess CO₂

• Enhances sleep quality

• Reduces daytime fatigue and morning headaches

• Delays the onset of daytime respiratory failure

• Improves quality of life and survival

BiPAP is typically introduced at night and can be extended to daytime use as respiratory needs increase.

Importance of Regular Monitoring and Follow-up

A multidisciplinary approach is essential in managing respiratory and sleep issues in Duchenne Muscular Dystrophy (DMD)

. This includes:

• Regular pulmonary function tests

• Periodic sleep studies

• Home pulse oximetry if required

• Routine clinical assessments by a pediatric pulmonologist

This proactive monitoring allows for early identification and timely intervention, preventing complications and improving long-term outcomes.