From the Guidelines
A sleep study is indicated for myasthenia gravis patients when there are symptoms suggesting sleep-disordered breathing, such as daytime tiredness, fatigue, excessive daytime sleepiness, or a history of respiratory complications. According to the American College of Chest Physicians clinical practice guideline and expert panel report 1, sleep testing can be helpful when concern exists that pulmonary function tests (PFT) and clinical evaluation are not capturing complications such as hypoventilation. The guideline suggests considering sleep history and symptoms to determine the need for testing, with a consensus recommendation to use sleep testing to identify sleep-disordered breathing and minimal undesirable effects with no indication of harm 1.
Key Indications for Sleep Study
- Symptoms suggesting sleep-disordered breathing, such as daytime tiredness, fatigue, excessive daytime sleepiness
- History of respiratory complications
- Pediatric patients or adults with symptoms such as daytime tiredness, fatigue, excessive daytime sleepiness, history of respiratory complications
- When PFT and clinical evaluation are not capturing complications such as hypoventilation
Diagnostic Testing
Polysomnography is not necessary for adult patients to manage neuromuscular disease (NMD) if PFT or overnight oximetry (ONO) criteria support using non-invasive ventilation (NIV) 1. However, full polysomnography is suggested at least once in pediatric patients and adults with symptoms such as daytime tiredness, fatigue, excessive daytime sleepiness, history of respiratory complications. Home-based overnight capnography is feasible and has been used as one of the criteria to initiate respiratory support 1.
Clinical Considerations
The evaluation is crucial before initiating medications that may worsen respiratory function, such as high-dose corticosteroids or certain immunosuppressants. Early detection and treatment of sleep-disordered breathing in these patients can improve quality of life, reduce exacerbation risk, and optimize overall disease management. Transcutaneous and end-tidal CO2 may be helpful in detecting hypoventilation and initiating and managing NIV 1.
From the Research
Indications for Sleep Study in Myasthenia Gravis
A sleep study may be indicated for patients with myasthenia gravis (MG) who experience:
- Excessive daytime sleepiness (EDS) 2
- Poor sleep quality 3, 4
- Sleep-related respiratory disorders, such as sleep-disordered breathing (SDB) 3, 4
- Restless syndrome 3
- Disturbed sleep patterns, including difficulty initiating or maintaining sleep 5, 6
Patient Characteristics
Sleep studies may be particularly relevant for MG patients with:
- Higher disease severity, as measured by the Myasthenia Gravis Foundation of America (MGFA) grade 5
- Greater neck circumference, which may be associated with sleep apnea 5
- Higher body mass index (BMI), which may contribute to sleep disturbances 5
- Older age, which may be associated with EDS 5
Assessment Tools
Sleep studies in MG patients may utilize various assessment tools, including: