[Clinical factors affecting quality of life and treatment targets in patients with myasthenia gravis].

Presently, myasthenia gravis (MG) is seldom lethal. However, full remission without immune treatment is not common, and many patients still find it difficult to maintain daily activities. To both determine factors affecting health-related quality of life (QOL) and propose an appropriate treatment target for patients with MG, we evaluated 640 consecutive patients with MG seen at 11 neurological centers. Two-year follow-up data were obtained for 282 patients. Correlations between detailed clinical facotrs and the Japanese version of the 15-item MG-specific QOL scale were analyzed.In the cross-sectional analysis of 640 MG patients, multivariate regression revealed that disease severity as evaluated by MG Composite (p < 0.0001), but not quantitative MG score, total dose of oral prednisolone (p = 0.002), but not current dose, and Cushingoid appearance index (p = 0.0004) showed significant negative effects on QOL. Achieving status of Minimal Manifestations or better with prednisolone ≤ 5 mg/day was found to exert a major positive impact on QOL in both the cross-sectional and 2-year follow-up patient samples and can be recommended as a treatment target.