Table 1.
Clinical characteristics of drug‐refractory and non‐drug‐refractory myasthenia gravis patients and statistical analysis results.
| Drug‐refractory MG (n = 84) | Non‐drug‐refractory MG (n = 906) | p value | |
|---|---|---|---|
| Age at onset | 44.4 (SD 18.0) | 58.4 (SD 18.8) | <0.0001 |
| Age at onset >65 yo (%) | 12 (14.3) | 428 (47.2) | <0.0001 |
| Sex (female %) | 63 (75) | 410 (45.3) | <0.0001 |
| Antibodies (%) | AChR 68 (81) | AChR 774 (85.4) | 0.037 |
| MuSK 5 (6) | MuSK 21 (2.3) | ||
| AChR+MuSK 1 (1.2) | AChR+MuSK 1 (0.1) | ||
| Seronegative 10 (11.9) | Seronegative 110 (12.1) | ||
| Thymoma (%) | 15/82 (18.3) | 113/890 (12.7) | 0.152 |
| MGFA classification at onset (%) | |||
| I | 18 (21.4) | 375 (41.4) | |
| II | 29 (34.5) | 317 (35.0) | |
| III | 19 (22.6) | 125 (13.8) | <0.0001 |
| IV | 11 (13.1) | 49 (5.4) | |
| V | 3 (3.6) | 22 (2.4) | |
| Unknown | 4 (4.8) | 18 (2.0) | |
| MGFA classification at maximal worsening (%) | |||
| I | 6 (7.1) | 247 (27.3) | |
| II | 13 (15.5) | 260 (28.7) | |
| III | 30 (35.7) | 213 (23.5) | <0.0001 |
| IV | 20 (23.8) | 76 (8.4) | |
| V | 9 (10.7) | 61 (6.7) | |
| Unknown | 6 (7.1) | 49 (5.4) | |
| Generalized MG (onset/maximal worsening, %) | 62/80 (77.5) | 513/888 (57.8) | <0.0001 |
| 72/78 (92.3) | 610/857 (71.2) | <0.0001 | |
| Bulbar symptoms (onset/maximal worsening, %) | 38/80 (47.5) | 345/888 (38.9) | 0.130 |
| 49/78 (62.8) | 419/857 (48.9) | 0.018 | |
| Life‐threatening events (onset/maximal worsening, %) | 11/80 (13.8) | 67/888 (7.5) | 0.051 |
| 22/78 (28.2) | 126/857 (14.7) | 0.002 | |
| Myasthenic crisis (onset/maximal worsening, %) | 3/80 (3.8) | 22/888 (2.5) | 0.492 |
| 9/78 (11.5) | 61/857 (7.1) | 0.156 | |
MG, myasthenia gravis; MGFA, Myasthenia Gravis Foundation of America; AChR, acetylcholine receptor; MuSK, muscle‐specific tyrosine kinase.