Excessive Daytime Sleepiness in Patients with Myasthenia Gravis

Area of Science:

• Neurology
• Sleep Medicine

Background:

• Myasthenia gravis (MG) is a neuromuscular disease affecting voluntary muscle strength.
• Excessive daytime sleepiness (EDS) is a common but understudied symptom in MG.
• Previous research has not extensively utilized objective sleepiness measures in MG patients.

Purpose of the Study:

• To investigate the prevalence of EDS in myasthenia gravis using objective sleep testing.
• To compare the diagnostic efficacy of objective sleepiness measures versus subjective sleepiness questionnaires in MG.
• To determine if MG patients exhibit objective signs of EDS.

Main Methods:

• Recruited eight patients with mild-to-moderate myasthenia gravis.
• Administered objective sleep assessments: Maintenance of Wakefulness Test (MWT), Polysomnography (PSG), Multiple Sleep Latency Test (MSLT).
• Utilized subjective sleepiness and fatigue questionnaires, including the Epworth Sleepiness Scale (ESS).

Main Results:

• Seven out of eight MG patients showed objective evidence of EDS.
• Only two patients had abnormal Epworth Sleepiness Scale scores.
• Objective sleepiness measures and subjective scores demonstrated poor correlation.

Conclusions:

• Objective testing is superior to subjective scales like the ESS for detecting EDS in myasthenia gravis.
• The Epworth Sleepiness Scale may be inadequate for diagnosing EDS in MG, potentially leading to under-reporting.
• Myasthenia gravis patients frequently experience significant daytime sleepiness that requires objective assessment.