Predictors and Prognostic Factors of Myasthenia Gravis Outcome

Change in MG-specific Activities of Daily Living scale (MG-ADL).

The MG Activities of Daily Living (MG- ADL) Scale an easily administered, 8-item questionnaire. Each item is graded on a 4- point symptom severity scale (0 = normal, 3 = most severe), with the total score ranging from 0 to 24. Test items emphasize the functional impact of muscle weakness (eg, the ability to comb one's hair or brush one's teeth instead of hand grip or outstretched arm strength tests) rather than its quantitation. The MG-ADL requires no special equipment or training and can be administered in 10 minutes. The MG-ADL test domains include ocular (2 items), oropharyngeal (3 items), respiratory (1 item), and extremity/limb (2 items).

Change in MG quality of life 15 (MG-QOL15).

Everyday clinical use led to the development of an abbreviated 15-item version, the MG-QOL15. These 15 items were derived from the mobility (9 items), symptoms (3 items), general contentment (1 item), and emotional well-being (2 items) domains of the 60-item version. Each of the items/statements (eg, "I have limited my social activity because of my condition") is scored by patients on a 5-point scale ranging from 0 ("not at all") to 4("very much") based on their experience over the previous 4 weeks; the item scores are summed to generate a total score ranging from 0 to 60.

Change in MG manual muscle testing (MG-MMT).

The MG-MMT assesses the strength or function of 30 muscle groups typically affected by MG and includes a total of 18 items, with 12 assessed bilaterally, and 6 assessed as single items (lid closure, cheek puff, tongue protrusion, jaw closure, neck flexion, and neck extension). Each item is scored on a 5- point severity scale, based on the severity of muscle weakness \[0 = no weakness, 1 = weak/mild (25%) impairment, 2 = weak/moderate (50%) impairment, 3 = weak/severe (75%) impairment, 4 = paralyzed/unable to perform\]. Bilateral scores are summed for a total item score, and all item scores are summed for a total MG-MMT score. MG-MMT scores range from 0 to 120; domains include ocular (3 items, including eyelid closure), facial/oropharyngeal (3 items), axial strength (neck flexion/extension; 2 items), and limb strength (10 items).

Change in MG composite (MGC) Score.

The MG Composite (MGC) Scale is considered a mixed outcome measure that incorporates both physician-evaluated and patient-reported outcome items. In creating this composite scale, the developers sought to minimize the number of items (and thus administration time), to maximize the sensitivity and clinical relevance of each item, and to weight items (as recommended by the Myasthenia Gravis Foundation of America MGFA task force) commensurate with their impact on functional status, QOL, overall health status, and prognosis.13 The MGC Scale is composed of individual items from outcome measures (including the quantitative myasthenia gravis score (QMG), the MG-ADL, and the MG-MMT). Total score spans from 0 to 50.

The proportion of patients with treatment related adverse effects.

Adverse effects of treatment of myasthenia gravis

The proportion of patients reaching minimal manifestations (MM) or better

Clinical statuses of patients are assessed and categorized according to Myasthenia Gravis Foundation of America (MGFA) postintervention status (PIS). It assesses the clinical state of MG patients at any time after institution of treatment for MG