Table 1.
Clinical and laboratory characteristics of the patients diagnosed with IgA nephropathy at the time of renal biopsy, and the patients classified by O-grades.
| Characteristic variable | a | b | P value | ||
|---|---|---|---|---|---|
| All patients | O-grade I | O-grade II | O-grade III | ||
| Number of patients, n [male, n (%)] | 871 [356 (41)] | 260 [101 (38.9)] | 525 [220 (41.9)] | 86 [35 (40.7)] | 0.7131 |
| At the time of biopsy | |||||
| Age (year) | 31 (24–41) | 30 (24–42) | 30 (24–40) | 34.5 (27–46.3) | 0.006 |
| Duration from onset to biopsy (year) | 3 (1–8) | 3 (1–8) | 4 (1–8) | 3 (1–8) | 0.73 |
| BMI (kg/m2) | 21.3 (19.6–23.5) | 21.4 (19.4–23.6) | 21.2 (19.6–23.4) | 21.7 (19.8–24.1) | 0.38 |
| MAP (mm Hg) | 89.7 (81.3–99) | 88 (80.2–97) | 89.3 (80.7–99.3) | 95 (86.6–106) | < 0.001 |
| Proteinuria (g/day) | 0.68 (0.3–1.4) | 0.34 (0.14–0.69) | 0.78 (0.4–1.49) | 1.73 (0.9–3.1) | < 0.001 |
| Haematuria (/HPF) | 20 (10–50) | 20 (10–50) | 30 (10–50) | 30 (10–100) | 0.015 |
| Serum creatinine (mg/dL) | 0.79 (0.67–1.0) | 0.78 (0.64–0.98) | 0.78 (0.68–1.0) | 0.96 (0.77–1.29) | < 0.001 |
| eGFR (mL/min/1.73 m2) | 77.0 (60.0–95.6) | 79.6 (65.5–96.9) | 78.0 (60.4–98.0) | 59.0 (48.8–75.7) | < 0.001 |
| BUN (mg/dL) | 14.8 (12.2–17.9) | 14.4 (11.9–16.8) | 14.7 (12.1–17.8) | 17.6 (13.6–21.5) | < 0.001 |
| Uric acid (mg/dL) | 5.5 (4.5–6.7) | 5.1 (4.2–6.4) | 5.5 (4.6–6.8) | 6.3 (5.3–7.3) | < 0.001 |
| Total cholesterol (mg/dL) | 192.0 (168–225) | 190 (165–215) | 192 (168–225) | 217 (175–248) | < 0.001 |
| Oxford classification | |||||
| M0, M1, n (%) | 441, 430 (49) | 220, 40 (15) | 213, 312 (59) | 8, 78 (91) | < 0.001 |
| E0, E1, n (%) | 479, 391 (45) | 252, 8 (3.1) | 220, 304 (58) | 7, 79 (92) | < 0.001 |
| S0, S1, n (%) | 243, 628 (72) | 160, 100 (38) | 75, 450 (86) | 8, 78 (91) | < 0.001 |
| T0, T1, T2, n (%) | 631, 189 (22), 51 (6) | 250, 10 (5.3), 0 (0) | 367, 131 (25), 27 (5.1) | 14, 48 (56), 24 (28) | < 0.001 |
| C0, C1, C2, n (%) | 454, 370 (42), 46 (5) | 255, 5 (1.9), 0 (0) | 199, 311 (59), 14 (2.7) | 0, 54 (63), 32 (37) | < 0.001 |
| Total score | 2.5 ± 1.6 | 0.63 ± 0.48 | 3.0 ± 0.78 | 5.2 ± 0.47 | < 0.001 |
| Treatments | |||||
| Corticosteroids/immunosuppressors | 426 (49) | 77 (30) | 285 (54) | 64 (74) | < 0.001 |
| RAS inhibitors | 293 (34) | 65 (25) | 186 (35) | 42 (49) | < 0.001 |
| At the final follow-up | |||||
| Observation period (years) | 8 (4–10) | 7.5 (4–10) | 9 (4–10) | 8.3 (4.5–10) | 0.23 |
| Number of patients with ESRD, n (%) | 115 (13) | 8 (3.1) | 49 (9.3) | 18 (21) | < 0.001 |
O-grade new grading system utilising the total score of each variable in the Oxford classification (MEST-C), BMI body mass index, MAP mean arterial pressure, HPF high-power field, M1 mesangial hypercellularity, E1 endocapillary hypercellularity, S1 segmental glomerulosclerosis/adhesion, T1 tubular atrophy/interstitial fibrosis 26–50%, T2 50%, C1 cellular/fibrocellular crescents 1–25%, C2 > 25%; RAS, renin-angiotensin system.