Baseline characteristics and laboratory findings
| Variables | G1-1, 2 (N=465) | G1-3 (n=103) Extremely rapid eGFR decline | P value | G2-1, 2 (N=2139) | G2-3 (N=513) Extremely rapid eGFR decline | P value | G3-1, 2 (N=2215) | G3-3 (N=222) Extremely rapid eGFR decline | P value |
| Age (years)* | 67(51, 76) | 74(65.5, 80) | <0.001 | 73(65, 79) | 75(67, 80) | 0.002 | 74(67, 81) | 76(65, 83) | 0.402 |
| Female sex (%) | 54.6 | 48.5 | 0.264 | 44.0 | 46.8 | 0.253 | 39.9 | 42.8 | 0.396 |
| Comorbidity of DM (%) | 30.5 | 24.3 | 0.207 | 25.2 | 24.2 | 0.614 | 26.0 | 19.8 | 0.042 |
| History of AKI (%) | 2.1 | 1.9 | 0.895 | 1.6 | 2.3 | 0.243 | 2.6 | 5.0 | 0.045 |
| BMI (kg/m2) | 22.4, 4.4 | 21.9, 4.2 | 0.236 | 23.0, 3.9 | 22.3, 3.9 | <0.001 | 22.9, 3.8 | 22.1, 3.6 | 0.013 |
| SBP (mm Hg) | 131, 27 | 134, 29 | 0.479 | 134, 26 | 132, 26 | 0.107 | 134, 26 | 132, 28 | 0.424 |
| DBP (mm Hg) | 76, 17 | 73, 18 | 0.059 | 75, 14 | 74, 16 | 0.226 | 73, 15 | 73, 16 | 0.995 |
| Use of RASB (%) | 43.4 | 46.6 | 0.559 | 52.0 | 52.2 | 0.933 | 59.3 | 52.2 | 0.041 |
| eGFR (mL/min/1.73 m2) | 99.8, 17.8 | 99.4, 23.9 | 0.251 | 62.5, 10.2 | 64.2, 10.7 | <0.001 | 43.2, 7.3 | 48.7, 10.3 | <0.001 |
| Serum creatinine (mg/dL) | 0.56, 0.11 | 0.56, 0.13 | 0.696 | 0.84, 0.16 | 0.81, 0.17 | <0.001 | 1.21, 0.37 | 1.09, 0.38 | <0.001 |
| BUN (mg/dL) | 14.0, 4.9 | 14.8, 6.5 | 0.785 | 17.3, 5.3 | 17.7, 6.2 | 0.610 | 22.4, 7.2 | 21.1, 8.6 | <0.001 |
| Haemoglobin (mg/dL) | 12.3, 2.1 | 11.3, 2.3 | <0.001 | 12.7, 1.9 | 11.9, 2.2 | <0.001 | 12.0, 2.0 | 11.2, 2.2 | <0.001 |
| Serum T-chol (mg/dL) | 192, 54 | 163, 44 | <0.001 | 189, 44 | 181, 45 | <0.001 | 188, 45 | 181, 60 | 0.003 |
| Serum uric acid (mg/dL) | 4.7, 1.6 | 4.7, 1.9 | 0.819 | 5.7, 1.5 | 5.5, 1.6 | 0.077 | 6.4, 1.6 | 6.2, 2.0 | 0.047 |
| Serum albumin (g/dL) | 3.55, 0.74 | 3.17, 0.78 | <0.001 | 3.91, 0.55 | 3.64, 0.69 | <0.001 | 3.86, 0.56 | 3.41, 0.69 | <0.001 |
| CRP (mg/dL)* | 0.3(0.3, 1.6) | 1.2(0.3, 4.1) | <0.001 | 0.3(0.3, 0.6) | 0.3(0.3, 1.5) | <0.001 | 0.3(0.3, 0.6) | 0.7(0.3, 2.8) | <0.001 |
| Transferrin saturation (%) | 24.0, 14.6 | 25.3, 13.6 | 0.512 | 24.8, 13.4 | 24.1, 13.5 | 0.560 | 26.5, 13.3 | 23.8, 14.5 | 0.024 |
| Ferritin (ng/mL)* | 118(35, 307) | 152(74, 580) | 0.189 | 111(44, 271) | 208(61, 381) | 0.038 | 164(63, 328) | 190(87, 423) | 0.397 |
| Haemoglobin A1c (%) | 6.8, 1.8 | 6.8, 2.1 | 0.660 | 6.4, 1.4 | 6.2, 1.2 | 0.007 | 6.3, 1.2 | 6.1, 1.0 | 0.137 |
| Urine protein† | 1.6, 1.5 | 1.3, 1.3 | 0.053 | 1.2, 1.4 | 1.0, 1.3 | 0.029 | 1.4, 1.5 | 1.4, 1.5 | 0.983 |
| Urine protein‡ | 2(0, 3) | 1(0, 2) | <0.001 | 0(0, 2) | 0(0, 2) | 0.029 | 1(0, 3) | 1(0, 3) | 0.983 |
Data are shown as mean (SD), value (%).
*Median (first quartile, third quartile), as appropriate.
†Continuous value of urine protein test by dipstick.
‡Semi-quantitative test of urine protein by dipstick 50% (25%, 75%).
AKI, acute kidney injury; BMI, body mass index; BUN, blood urea nitrogen; CRP, C reactive protein; DBP, diastolic blood pressure; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; RASB, renin–angiotensin system blocker; SBP, systolic blood pressure; T-chol, total cholesterol.