OBJECTIVES: Myasthenia Gravis (MG) is a neuro-muscular junction disorder caused by autoantibodies disrupting neuromuscular transmission resulting in impaired activities of daily living. The relationship between MG severity and ADL is not well understood. Using the MG-ADL score, a measure of MG impact on ADL, we assess how increased MG severity impacts ADL.

METHODS: Data were drawn from the Adelphi MG Disease Specific Programme™, a point-in-time survey of MG-treating physicians in France, Germany, Italy, Spain, the UK and USA, March – September 2020. Physicians provided data on consecutively consulting MG patients including demographics, clinical characteristics, MG Foundation of America (MGFA) classification of severity and disease impact. Demographics and MGFA score analyses were descriptive, modified MG-ADL score was created using questioning close to the validated tool and a linear regression was run versus MGFA class.

RESULTS: Data were provided by 222 physicians on 1232 MG patients with modified MG-ADL scores (Mean age: 54.2 [standard deviation; SD±16.32], 50.2% female). Mean time from diagnosis to survey was 3.8 years (SD±4.78). MGFA class at survey was reported for all patients. In all, 29.8% were MGFA class I with ocular symptoms only, 47.0% were class II (mild) and 23.2% class III/IV (moderate/severe). Class I patients had a mean modified MG-ADL score of 1.8 (SD±1.97), those in class II averaged 3.0 (SD±2.98) and those in class III/IV averaged 6.0 (SD±4.26). Class II patients were associated with a 1.6 rise in MG-ADL from class I (p<0.01). Class III/IV patients were associated with a 4.2 rise in MG-ADL score from class I (p<0.01).

CONCLUSIONS: These results show worse MG severity aligns with higher impairment of ADL. Treatments that reduce MG severity would greatly benefit patients and improve ADLs. Further patient-centric research could shed light on the specific aspects of the MG-ADL measure which are most burdensome to patients with MG.