Baseline characteristics of the patients according to CKD severity.
| Characteristics | CKD 3b, n = 74 | CKD 4, n = 44 | p |
|---|---|---|---|
| Age, yrs, mean ± SD | 44.7 ± 13.4 | 40.8 ± 13.6 | 0.129 |
| Female, % (n) | 87.8 (65) | 81.8 (36) | 0.368 |
| SLE duration, yrs, mean ± SD | 12.3 ± 11.4 | 9.3 ± 6.7 | 0.116 |
| Race/ethnicity, % (n) | 0.35 | ||
| White | 67.6 (50) | 56.8 (25) | |
| Black | 17.6 (13) | 15.9 (7) | |
| Chinese | 4.1 (3) | 11.4 (5) | |
| Other | 10.8 (8) | 15.9 (7) | |
| LN class, % (n) | 0.655 | ||
| II | 27 (20) | 20.5 (9) | |
| III | 18.9 (14) | 15.9 (7) | |
| IV | 29.7 (22) | 43.2 (19) | |
| V | 16.2 (12) | 15.9 (7) | |
| IV/V | 2.7 (2) | 0 (0) | |
| Activity index, mean ± SD | 4.5 ± 4.1 | 5.8 ± 4.8 | 0.149 |
| Chronicity index, mean ± SD | 2.3 ± 2.6 | 2.8 ± 2.9 | 0.334 |
| Creatinine, μmol/l, mean ± SD | 149 ± 20 | 202 ± 56 | < 0.001 |
| eGFR, ml/min/1.73 m2, mean ± SD | 37.5 ± 5.5 | 24.4 ± 6.1 | < 0.001 |
| Proteinuria > 0.5 g/day, % (n) | 58.1 (43) | 54.5 (24) | 0.558 |
| Proteinuria, g/day, median (IQR) | 1.1 (0.4–3.4) | 1.0 (0.3–3.3) | 0.952 |
| Active urinary sediment, n (%)* | 3 (4.1) | 2 (4.5) | 0.898 |
| Anti-dsDNA+, % (n) | 59.5 (44) | 54.5 (24) | 0.795 |
| Low C3/C4, % (n) | 48.6 (36) | 50 (22) | 0.887 |
| Hb < 12 g/dl, % (n) | 27 (20) | 47.7 (21) | 0.022 |
| Systolic BP, mmHg, mean ± SD | 137 ± 22 | 139 ± 24 | 0.51 |
| Diastolic BP, mmHg, mean ± SD | 84 ± 12 | 85 ± 12 | 0.635 |
| Antihypertensives, % (n) | 63.5 (47) | 68.2 (30) | 0.795 |
| Treated with ACEI/ARB, % (n) | 51.4 (38) | 47.7 (21) | 0.703 |
| Diabetes, % (n) | 12.2 (9) | 13.6 (6) | 0.725 |
| Treated with statins, % (n) | 24.3 (18) | 20.5 (9) | 0.628 |
| Glucocorticosteroids, % (n) | 82.4 (61) | 86.4 (38) | 0.574 |
| Mean prednisone dose, mg/day, mean ± SD | 21.9 ± 19.2 | 19.3 ± 17.0 | 0.495 |
| Cumulative glucocorticosteroid dose, g, median** | 16.4 | 16.6 | 0.796 |
| Antimalarials, % (n) | 39.2 (29) | 36.4 (16) | 0.76 |
| Immunosuppressives, % (n) | 51.4 (38) | 63.6 (28) | 0.194 |
↵* Casts and/or hematuria > 10 red blood cells per high power field.
↵** From LN diagnosis (time of biopsy) up to the baseline. CKD: chronic kidney disease; SLE: systemic lupus erythematosus; LN: lupus nephritis; eGFR: estimated glomerular filtration rate; IQR: interquartile range; Hb: hemoglobin; BP: blood pressure; ACEI: angiotensin-converting enzyme inhibitors; ARB: angiotensin receptor blockers.