Table 1 Comparison of the Demographic and Baseline Characteristics of unmatched and matched AKI and non-AKI groups
From: Role of elevated red cell distribution width on acute kidney injury patients after cardiac surgery
|  | Unmatched Cohort (n = 10,274) | P-value | Matched Cohort (n = 3146) | P-value | ||
|---|---|---|---|---|---|---|
Non-AKI group (n = 6909) | AKI group(n = 3364) | Non-AKI group (n = 1573) | AKI group (n = 1573) | |||
Age (years) | 51.7 ± 14.0 | 56.8 ± 12.3 | <  0.001 | 54.6 ± 12.0 | 54.4 ± 12.1 | 0.782 |
Male, sex | 3584 (51.9%) | 2233 (66.6%) | <  0.001 | 966 (61.4%) | 913 (58.0%) | 0.059 |
Comorbidities | ||||||
 Hypertension | 1748 (25.3%) | 1177 (35%) | <  0.001 | 422 (26.8%) | 457 (29.1%) | 0.177 |
 DM | 628 (9.1%) | 386 (11.5%) | <  0.001 | 139 (8.8%) | 151 (9.6%) | 0.498 |
Creatinine, μmol/L | 75.7 ± 20.6 | 83.6 ± 29.5 | <  0.001 | 77.1 ± 17.3 | 77.8 ± 19.7 | 0.325 |
 eGFR | 93.0 ± 22.1 | 87.3 ± 25.3 | <  0.001 | 91.5 ± 20.7 | 91.0 ± 24.1 | 0.566 |
 BUN | 6.1 ± 2.1 | 7.0 ± 2.8 | <  0.001 | 6.2 ± 1.9 | 6.3 ± 1.8 | 0.063 |
 Albumin baseline | 40.6 ± 3.3 | 40.1 ± 3.3 | <  0.001 | 40.0 ± 3.4 | 39.9 ± 3.5 | 0.162 |
 Hemoglobin, g/dL | 136.5 ± 14.6 | 137.3 ± 15.9 | 0.005 | 134.7 ± 17.0 | 133.6 ± 18.7 | 0.093 |
 WBC, 1000/μL | 6.4 ± 2.0 | 6.5 ± 2.2 | 0.033 | 6.4 ± 2.4 | 6.4 ± 2.0 | 0.532 |
 Elevated RDW, % | 0.3 (0.0, 0.6) | 0.5 (0.1,1.0) | <  0.001 | 0.3 (0.0,0.7) | 0.5 (0.1,1.1) | < 0.001 |
 Platelet fl | 188.8 ± 56.7 | 177.3 ± 56.4 | <  0.001 | 189.2 ± 62.1 | 178.2 ± 58.7 | < 0.001 |
BMI, kg/m2 | 22.9 ± 3.0 | 23.5 ± 3.2 | 0.013 | 22.6 ± 3.2 | 23.3 ± 3.7 | < 0.001 |
 SUA | 351.0 ± 104.7 | 394.0 ± 138.6 | <  0.001 | 355.6 ± 101.0 | 377.0 ± 108.6 | < 0.001 |
NYHA functional class | ||||||
 I-II | 3420 (49.5%) | 1370 (40.7) | <  0.001 | 755 (48.0%) | 610 (38.8%) | < 0.001 |
 III-IV | 3489 (50.5%) | 1995 (59.3) | <  0.001 | 818 (52.0%) | 963 (61.2%) | < 0.001 |
LVEF% | 62.4 ± 8.3 | 61.4 ± 19.3 | 0.071 | 62.1 ± 8.1 | 61.3 ± 9.4 | 0.092 |
CPB time (min) | 81.0 (65.0, 105.0) | 101.0 (78.0, 128.0) | <  0.001 | 80.5 (65.0,105.0) | 99.0 (78.0,126.0) | < 0.001 |
ACC time (min) | 48.0 (36.0, 67.0) | 58.0 (43.0, 78.0) | <  0.001 | 48.0 (37.0,67.0) | 55.0 (41.0,78.0) | < 0.001 |
Pre-operative coronary angiography n (%) | 2543 (36.8) | 1528 (45.4) | < 0.001 | 690 (43.9%) | 617 (39.2%) | 0.009 |
Time interval between coronary angiogram and cardiac surgery (days) | 4 (2, 6) | 4 (2, 6) | 0.212 | 3 (2,6) | 3 (2,6) | 0.981 |