Table 1.
Patient characteristics in the CureGN IgA nephropathy (IgAN)/IgA vasculitis (IgAV) cohort, by diagnosis
| All N = 667 |
IgAN n = 506 |
IgAV n = 161 |
P valuea | |
|---|---|---|---|---|
| Median (IQR) or n (%) | Median (IQR) or n(%) | Median (IQR) or n (%) | ||
| Demographicsb | ||||
| Age at diagnosis, yr | 23.9 (12.1–40.9) | 28.8 (14.7–43.5) | 12.7 (7.6–22.4) | <0.001 |
| Age at biopsy, yr | 24.3 (12.6–41.8) | 29.6 (15.0–43.9) | 13.0 (8.3–22.4) | <0.001 |
| Time from diagnosis to enrollment, yr | 1.0 (0.3–2.9) | 1.2 (0.3–3.1) | 0.6 (0.2–1.5) | <0.001 |
| Sex, male | 403 (60.4%) | 303 (59.9%) | 100 (62.1%) | 0.61 |
| Race, white | 513 (81.6%) | 374 (78.9%) | 139 (89.7%) | 0.003 |
| Hispanic/Latino | 100 (15.1%) | 81 (16.1%) | 19 (11.8%) | 0.18 |
| Family history of kidney disease | 188 (29.3%) | 149 (30.5%) | 39 (25.3%) | 0.22 |
| At biopsyc | ||||
| UPCR | 1.5 (0.7–3.3) | 1.4 (0.7–3.0) | 1.8 (0.7–4.6) | 0.04 |
| 3 ≤ UPCR | 141 (28.5%) | 89 (24.9%) | 52 (38.0%) | 0.01 |
| 1 ≤ UPCR < 3 | 177 (35.8%) | 140 (39.2%) | 37 (27.0%) | |
| 0.3 ≤ UPCR < 1 | 121 (24.5%) | 86 (24.1%) | 35 (25.5%) | |
| UPCR < 0.3 | 55 (11.1%) | 42 (11.8%) | 13 (9.5%) | |
| Hematuria | ||||
| Negative | 27 (5.5%) | 24 (6.8%) | 3 (2.2%) | 0.03 |
| Trace | 17 (3.5%) | 15 (4.3%) | 2 (1.4%) | |
| 1+ Small, 11–25 | 41 (8.4%) | 33 (9.4%) | 8 (5.8%) | |
| 2+ Moderate, 26–50 | 105 (21.5%) | 78 (22.2%) | 27 (19.6%) | |
| 3+ Large, 51–250 | 299 (61.1%) | 201 (57.3%) | 98 (71.0%) | |
| Serum albumin, g/dl | 3.7 (3.2–4.1) | 3.8 (3.4–4.1) | 3.4 (2.9–3.8) | <0.001 |
| Serum albumin <3 g/dl | 91 (18.2%) | 53 (14.5%) | 38 (27.9%) | <0.001 |
| eGFR, ml/min per 1.73 m2 | 78.7 (46.1–110.9) | 70.6 (41.8–101.6) | 103.5 (70.3–122.5) | <0.001 |
| 90 ≤ eGFR | 239 (41.6%) | 150 (35.4%) | 89 (59.3%) | <0.001 |
| 60 ≤ eGFR < 90 | 131 (22.8%) | 97 (22.9%) | 34 (22.7%) | |
| 30 ≤ eGFR < 60 | 142 (24.7%) | 127 (30.0%) | 15 (10.0%) | |
| eGFR <30 | 62 (10.8%) | 50 (11.8%) | 12 (8.0%) | |
| At enrollmentd | ||||
| UPCR | 0.6 (0.2–1.7) | 0.7 (0.2–1.8) | 0.5 (0.2–1.6) | 0.37 |
| 3 ≤ UPCR | 81 (14.9%) | 58 (14.4%) | 23 (16.2%) | 0.33 |
| 1 ≤ UPCR < 3 | 138 (25.3%) | 110 (27.3%) | 28 (19.7%) | |
| 0.3 ≤ UPCR < 1 | 147 (27.0%) | 104 (25.8%) | 43 (30.3%) | |
| UPCR <0.3 | 179 (32.8%) | 131 (32.5%) | 48 (33.8%) | |
| Hematuria | ||||
| Negative | 84 (16.1%) | 68 (17.6%) | 16 (11.9%) | 0.02 |
| Trace | 48 (9.2%) | 37 (9.6%) | 11 (8.1%) | |
| 1+ Small, 11–25 | 72 (13.8%) | 60 (15.5%) | 12 (8.9%) | |
| 2+ Moderate, 26–50 | 126 (24.1%) | 95 (24.5%) | 31 (23.0%) | |
| 3+ Large, 51–250 | 192 (36.8%) | 127 (32.8%) | 65 (48.1%) | |
| Serum albumin, g/dl | 4.0 (3.6–4.3) | 4.0 (3.7–4.3) | 3.9 (3.4–4.3) | 0.03 |
| Serum albumin <3 g/dl | 48 (9.7%) | 27 (7.3%) | 21 (17.1%) | 0.001 |
| eGFR, ml/min per 1.73 m2 | 82.9 (48.8–105.2) | 75.8 (43.5–100.1) | 100.1 (82.4–118.7) | <0.001 |
| 90 ≤ eGFR | 261 (43.0%) | 167 (36.1%) | 94 (64.8%) | <0.001 |
| 60 ≤ eGFR < 90 | 150 (24.7%) | 116 (25.1%) | 34 (23.4%) | |
| 30 ≤ eGFR < 60 | 133 (21.9%) | 122 (26.4%) | 11 (7.6%) | |
| eGFR <30 | 63 (10.4%) | 57 (12.3%) | 6 (4.1%) | |
| Hypertensione | 121 (19.1%) | 89 (18.5%) | 32 (20.6%) | 0.56 |
| Trajectoryf | ||||
| eGFR higher at enrollment than at biopsy | 215 (40.6%) | 156 (39.6%) | 59 (43.7%) | 0.40 |
| UPCR lower at enrollment than at biopsy | 267 (62.8%) | 186 (62.0%) | 81 (64.8%) | 0.59 |
| UPCR ever <0.3 prior to or at enrollment | 247 (39.3%) | 184 (38.9%) | 63 (40.6%) | 0.70 |
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.