Table 2.
Patient characteristics in the CureGN IgA nephropathy (IgAN)/IgA vasculitis (IgAV) cohort, by diagnosis and age
| IgAN |
IgAV |
P valuea |
||||||
|---|---|---|---|---|---|---|---|---|
| Pediatric n = 173 |
Adult n = 333 |
Pediatric n = 112 |
Adult n = 49 |
IgAN Ped. versus Adult | IgAV Ped. versus Adult | Ped. IgAN versus IgAV | Adult IgAN versus IgAV | |
| Median (IQR) or n (%) | Median (IQR) or n (%) | Median (IQR) or n (%) | Median (IQR) or n (%) | |||||
| Demographicsb | ||||||||
| Age at diagnosis, yr | 12.1 (9.0–14.9) | 38.3 (29.1–50.0) | 9.1 (6.8–13.3) | 34.6 (24.0–48.5) | <0.001 | <0.001 | <0.001 | 0.13 |
| Age at biopsy, yr | 12.5 (9.9–15.2) | 39.6 (30.1–50.7) | 9.5 (6.9–13.6) | 35.4 (25.8–48.5) | <0.001 | <0.001 | <0.001 | 0.13 |
| Time from diagnosis to enrollment, yr | 1.3 (0.4–3.0) | 1.1 (0.3–3.3) | 0.6 (0.2–1.5) | 0.8 (0.2–1.9) | 0.66 | 0.57 | <0.001 | 0.10 |
| Sex, male | 107 (61.8%) | 196 (58.9%) | 71 (63.4%) | 29 (59.2%) | 0.51 | 0.61 | 0.79 | 0.97 |
| Race, white | 136 (82.4%) | 238 (77.0%) | 99 (91.7%) | 40 (85.1%) | 0.17 | 0.22 | 0.03 | 0.21 |
| Hispanic/Latino | 21 (12.2%) | 60 (18.1%) | 12 (10.7%) | 7 (14.3%) | 0.09 | 0.52 | 0.70 | 0.51 |
| Family history of kidney disease | 51 (30.5%) | 98 (30.5%) | 25 (23.6%) | 14 (29.2%) | 1.00 | 0.46 | 0.21 | 0.85 |
| At biopsyc | ||||||||
| UPCR | 1.1 (0.3–2.3) | 1.6 (0.9–3.3) | 2.1 (0.7–5.0) | 1.5 (0.7–3.7) | <0.001 | 0.36 | <0.001 | 0.76 |
| 3 ≤ UPCR | 22 (18.0%) | 67 (28.5%) | 41 (40.6%) | 11 (30.6%) | <0.001 | 0.18 | 0.001 | 0.68 |
| 1 ≤ UPCR < 3 | 40 (32.8%) | 100 (42.6%) | 24 (23.8%) | 13 (36.1%) | ||||
| 0.3 ≤ UPCR < 1 | 32 (26.2%) | 54 (23.0%) | 24 (23.8%) | 11 (30.6%) | ||||
| UPCR <0.3 | 28 (23.0%) | 14 (6.0%) | 12 (11.9%) | 1 (2.8%) | ||||
| Hematuria | ||||||||
| Negative | 4 (3.1%) | 20 (9.0%) | 3 (2.9%) | 0 (0.0%) | <0.001 | 0.84 | 0.49 | 0.01 |
| Trace | 4 (3.1%) | 11 (5.0%) | 2 (2.0%) | 0 (0.0%) | ||||
| 1+ Small, 11–25 | 6 (4.6%) | 27 (12.2%) | 7 (6.9%) | 1 (2.8%) | ||||
| 2+ Moderate, 26–50 | 16 (12.3%) | 62 (28.1%) | 20 (19.6%) | 7 (19.4%) | ||||
| 3+ Large, 51–250 | 100 (76.9%) | 101 (45.7%) | 70 (68.6%) | 28 (77.8%) | ||||
| Serum albumin, g/dl | 3.7 (3.2–4.1) | 3.8 (3.4–4.2) | 3.4 (2.9–3.8) | 3.5 (2.9–3.8) | 0.07 | 0.63 | 0.001 | 0.002 |
| Serum albumin <3 g/dl | 23 (18.9%) | 30 (12.3%) | 28 (27.7%) | 10 (28.6%) | 0.10 | 0.92 | 0.12 | 0.01 |
| eGFR, ml/min per 1.73 m2 | 98.6 (75.9–122.0) | 51.8 (36.0–87.2) | 109.5 (82.4–127.7) | 67.3 (42.4–105.4) | <0.001 | <0.001 | 0.07 | 0.11 |
| 90 ≤ eGFR | 83 (59.7%) | 67 (23.5%) | 73 (67.0%) | 16 (39.0%) | <0.001 | <0.001 | 0.24 | 0.13 |
| 60 ≤ eGFR < 90 | 40 (28.8%) | 57 (20.0%) | 28 (25.7%) | 6 (14.6%) | ||||
| 30 ≤ eGFR < 60 | 13 (9.4%) | 114 (40.0%) | 4 (3.7%) | 11 (26.8%) | ||||
| eGFR <30 | 3 (2.2%) | 47 (16.5%) | 4 (3.7%) | 8 (19.5%) | ||||
| At enrollmentd | ||||||||
| UPCR | 0.3 (0.1–1.0) | 1.0 (0.3–2.2) | 0.5 (0.2–1.3) | 0.8 (0.2–2.4) | <0.001 | 0.22 | 0.07 | 0.54 |
| 3 ≤ UPCR | 14 (9.8%) | 44 (16.9%) | 17 (16.5%) | 6 (15.4%) | <0.001 | 0.24 | 0.13 | 0.91 |
| 1 ≤ UPCR < 3 | 22 (15.4%) | 88 (33.8%) | 16 (15.5%) | 12 (30.8%) | ||||
| 0.3 ≤ UPCR < 1 | 36 (25.2%) | 68 (26.2%) | 33 (32.0%) | 10 (25.6%) | ||||
| UPCR <0.3 | 71 (49.7%) | 60 (23.1%) | 37 (35.9%) | 11 (28.2%) | ||||
| Hematuria | ||||||||
| Negative | 24 (17.4%) | 44 (17.7%) | 15 (15.3%) | 1 (2.7%) | 0.06 | 0.11 | 0.55 | 0.02 |
| Trace | 10 (7.2%) | 27 (10.8%) | 7 (7.1%) | 4 (10.8%) | ||||
| 1+ Small, 11–25 | 17 (12.3%) | 43 (17.3%) | 6 (6.1%) | 6 (16.2%) | ||||
| 2+ Moderate, 26–50 | 29 (21.0%) | 66 (26.5%) | 24 (24.5%) | 7 (18.9%) | ||||
| 3+ Large, 51–250 | 58 (42.0%) | 69 (27.7%) | 46 (46.9%) | 19 (51.4%) | ||||
| Serum albumin, g/dl | 4.0 (3.7–4.3) | 4.0 (3.6–4.3) | 3.9 (3.4–4.2) | 3.9 (3.4–4.3) | 0.78 | 0.56 | 0.05 | 0.51 |
| Serum albumin <3 g/dl | 11 (9.2%) | 16 (6.4%) | 15 (16.1%) | 6 (20.0%) | 0.33 | 0.62 | 0.12 | 0.01 |
| eGFR, ml/min per 1.73 m2 | 96.5 (83.9–117.6) | 53.3 (36.5–84.4) | 104.6 (89.7–121.5) | 80.1 (49.2–100.2) | <0.001 | <0.001 | 0.05 | 0.001 |
| 90 ≤ eGFR | 98 (64.5%) | 69 (22.3%) | 77 (74.0%) | 17 (41.5%) | <0.001 | <0.001 | 0.42 | 0.02 |
| 60 ≤ eGFR < 90 | 48 (31.6%) | 68 (21.9%) | 23 (22.1%) | 11 (26.8%) | ||||
| 30 ≤ eGFR < 60 | 3 (2.0%) | 119 (38.4%) | 2 (1.9%) | 9 (22.0%) | ||||
| eGFR <30 | 3 (2.0%) | 54 (17.4%) | 2 (1.9%) | 4 (9.8%) | ||||
| Hypertensione | 20 (12.1%) | 69 (21.9%) | 24 (22.2%) | 8 (17.0%) | 0.01 | 0.46 | 0.03 | 0.45 |
| Trajectoryf | ||||||||
| eGFR higher at enrollment than at biopsy | 55 (42.3%) | 101 (38.3%) | 40 (39.6%) | 19 (55.9%) | 0.44 | 0.10 | 0.68 | 0.05 |
| UPCR lower at enrollment than at biopsy | 72 (64.9%) | 114 (60.3%) | 66 (68.8%) | 15 (51.7%) | 0.43 | 0.09 | 0.55 | 0.38 |
| UPCR ever <0.3 prior to or at enrollment | 94 (59.1%) | 90 (28.7%) | 46 (42.2%) | 17 (37.0%) | <0.001 | 0.54 | 0.01 | 0.25 |
eGFR, estimated glomerular filtration rate; IQR, interquartile range; UPCR, urine protein-to-creatinine ratio.
P value from Mann−Whitney U test for continuous variables, χ2 test, or Fisher exact test for categorical variables.
Less than 6% missing for demographic variables.
Total of 26% of UPCR, 27% of hematuria, 25% of serum albumin, and 14% of eGFR values unavailable at biopsy.
Total of 18% of UPCR, 22% of hematuria, 26% of serum albumin, 9% of eGFR, and 5% of hypertension values missing at enrollment.
Systolic blood pressure >140 or diastolic blood pressure >90 for adults; systolic or diastolic blood pressure >95th percentile for pediatric patients.
Total of 21% of eGFR trajectories and 36% of UPCR trajectories unavailable (trajectories require nonmissing values at biopsy and enrollment), and 6% of patients had no UPCR measurements recorded prior to or at enrollment.