Table 1. Demographic and clinical characteristics of the study participants.
| Variables | Healthy controls | IgA nephropathy | p |
|---|---|---|---|
| N | 490 | 140 | |
| Age (years) † | 37.82 ± 9.89 | 33.79 ± 8.96 | 0.001* |
| Sex (male/female) | 307/183 | 70/70 | 0.01** |
| BMI (kg/m2)† | - | 23.35 ± 4.67 | |
| SBP (mmHg) † | - | 121.25 ± 14.37 | |
| DBP (mmHg) † | - | 75.9 ± 12.34 | |
| Hemoglobin (g/L)‡ | 137 (132–143) | 134 (118.75–148.25) | 0.503* |
| Albumin (g/L)‡ | 48.8 (47.2–50.3) | 40.29 (34.74–44.7) | 0.001* |
| Creatinine (umol/L)‡ | 85.5 (74–95.75) | 87.5 (72.25–112.9) | 0.001* |
| BUN (mmol/L)‡ | 4.75 (4.19–5.56) | 5.66 (4.38–6.99) | 0.001* |
| eGFR (mL/min/1.73 m2)‡ | - | 102.02 (84.39–145.08) | |
| IgA (g/L)‡ | - | 2.60 (1.86–3.28) | |
| Serum Complement C3 (g/L)‡ | - | 0.92 (0.73–1.07) | |
| Serum Complement C4 (g/L)‡ | - | 0.21 (0.17–0.25) | |
| Proteinuria (g/day)‡ | - | 1.27 (0.54–2.73) | |
| Lee's glomerular grading system | |||
| Grade I | - | 21 (15.00%) | |
| Grade II | - | 29 (20.71%) | |
| Grade III | - | 53 (37.86%) | |
| Grade IV–V | - | 37 (26.43%) | |
| The Oxford classification of tubular atrophy/interstitial fibrosis | |||
| 0–25% | - | 126 (90.00%) | |
| 26–50% | - | 14 (10.00%) |
BMI: Body Mass Index; SBP: systolic blood pressure; DBP: diastolic blood pressure; BUN: blood urea nitrogen; eGFR: estimated glomerular filtration rate; IgA: immunoglobulin A; C3: complement 3; C4: complement 4.
†Data with normal distribution expressed as arithmetic mean ± standard deviation (SD);
‡Data with skew distribution were expressed as median (interquartile range);
*Statistical differences between groups tested using unpaired Student's t test;
**Statistical differences between groups tested using chi-square test.