Table 1.
Characteristics of the GDCN and French ANCA vasculitis cohorts*
| GDCN cohort (n = 347) | French cohort (n = 434) | P | |
|---|---|---|---|
| Age, years | |||
| Mean ± SD | 58 ± 18 | 56 ± 15 | 0.0009 |
| Median (range) | 63 (2–92) | 57 (2–87) | – |
| Men | 183 (53) | 237 (55) | 0.60 |
| African American | 33 (9) | 6 (1) | <0.0001 |
| White | 311 (90) | 409 (94) | 0.0169 |
| PR3 ANCA seropositive† | 140 (40) | 252 (58) | <0.0001 |
| Median followup, months | 45 | 44 | 0.69 |
| Diagnosis | <0.0001 | ||
| Wegener's granulomatosis | 59 (17) | 285 (66) | |
| Microscopic polyangiitis | 199 (57) | 143 (33) | |
| Kidney-limited disease | 89 (26) | 6 (1) | |
| Organ involvement | |||
| Kidney | 305 (88) | 308 (71) | <0.0001 |
| Lung | 169 (49) | 253 (58) | 0.0075 |
| Upper respiratory tract | 106 (31) | 270 (62) | <0.0001 |
| Skin | 87 (25) | 162 (37) | 0.0003 |
| Serum creatinine level, μmoles/liter | |||
| Mean ± SD | 422 ± 324 | 193 ± 211 | <0.0001 |
| Median (range) | 327 (44–1,909) | 107 (45–1,730) | – |
| Treatment | 0.50 | ||
| Corticosteroids alone | 46 (13) | 48 (11) | |
| Cyclophosphamide plus corticosteroids | 270 (78) | 356 (82) | |
| Other immunosuppressant plus corticosteroids | 15 (4) | 13 (3) | |
| No treatment | 16 (5) | 17 (4) | |
| Patients with ≥1 risk factor for relapse | 224 (65) | 337 (78) | <0.0001 |
| Outcome | |||
| Treatment resistance‡ | 76 (23) | 58 (14) | 0.0013 |
| Remission | 255 (77) | 359 (86) | 0.0013 |
| Relapse§ | 106 (42) | 193 (54) | 0.003 |
| Overall median time to relapse, months | 45 | 44 | 0.57 |
| Median time to relapse among patients experiencing relapse, months | 16 | 30 | 0.0009 |
*
Except where indicated otherwise, values are the number (%) of patients.
†
The group of patients with proteinase 3 antineutrophil cytoplasmic antibody (PR3 ANCA) included those with PR3 and/or cytoplasmic ANCA.
‡
In the Glomerular Disease Collaborative Network (GDCN) cohort, 331 patients were treated; in the French cohort, 417 patients were treated.
§
Percentages of patients who experienced a relapse are based on the numbers of patients in whom remission was achieved (255 in the GDCN cohort and 359 in the French cohort).