Table 1.
Demographic and Clinical Characteristics of the Participants at Baseline.*
| Characteristic | Prednisone Alone (N = 60) | Thymectomy plus Prednisone (N = 66) |
|---|---|---|
| Female sex — no. (%) | 39 (65) | 50 (76) |
| Age — yr | ||
| Median | 33 | 32 |
| Range | 18–64 | 18–63 |
| Race or ethnic group — no. (%)† | ||
| Asian | 4 (7) | 6 (9) |
| Black | 6 (10) | 7 (11) |
| Hispanic | 17 (28) | 17 (26) |
| Non-Hispanic white | 30 (50) | 31 (47) |
| Other | 3 (5) | 5 (8) |
| Therapy at enrollment — no. (%) | ||
| Pyridostigmine | 56 (93) | 60 (91) |
| Glucocorticoid | 47 (78) | 49 (74) |
| Previous therapy — no. (%) | ||
| Intravenous immune globulin | 13 (22) | 12 (18) |
| Plasma exchange | 7 (12) | 9 (14) |
| MGFA class — no. (%)‡ | ||
| IIa | 25 (42) | 25 (38) |
| IIb | 14 (23) | 18 (27) |
| III | 20 (33) | 21 (32) |
| IV | 1 (2) | 2 (3) |
| Duration of disease — yr | ||
| Median | 1.14 | 1.08 |
| Range | 0.15–4.38 | 0.02–4.41 |
| QMG score§ | 12.35±4.90 | 11.40±5.12 |
| Prednisone use at baseline | ||
| No. of patients (%) | 47 (78) | 49 (74) |
| Dose — mg | 42.49±23.52 | 43.43±28.92 |
Plus–minus values are means ±SD. There were no significant between-group differences in the characteristics at baseline. Percentages may not sum to 100 because of rounding.
Race and ethnic group were self-reported. Other race included mixed race, Native American, and Alaskan Native.
Myasthenia Gravis Foundation of America (MGFA) class II indicates mild generalized weakness, class III moderate generalized weakness, and class IV severe generalized weakness. A notation of “a” denotes predominantly limb or axial weakness, and “b” predominantly bulbar weakness.
Three participants in the group that received prednisone alone and one in the thymectomy group withdrew without completing the baseline Quantitative Myasthenia Gravis (QMG) test. QMG scores range from 0 to 39, with higher scores indicating more severe disease.