Disease-specific measure of quality of life for myasthenia gravis.

In 2000 a Task Force of the Myasthenia Gravis Foundation of America recommended development of a quality of life (QOL) measure specific for myasthenia gravis (MG). Extant investigations have relied solely on assessment of physical aspects of daily living in conceptualizing QOL, despite research that emphasizes the importance of including psychological factors. In the present study we developed a QOL questionnaire specific to MG (MG-QOL) that assesses both physical and psychological aspects of function. The MG-QOL questionnaire was administered as a secondary measure of efficacy in a recently completed prospective trial of mycophenolate mofetil involving 80 MG patients. Comparisons indicated that the MG-QOL performed better than a nondisease-specific measure of QOL, the SF-36, in demonstrating disease change as assessed by the primary measure, the Quantitative MG score (QMG). The MG-QOL correlated highly with the SF-36, and demonstrated stronger associations with independent physical ability ratings. Results from this study support the use of this new measure of QOL, both clinically and in treatment trials of MG.