Table 1.
Clinical data and outcomes
| Characteristics | Total (n=1222) | AKI (n=256) | No AKI (n=966) | P value |
| Age, years | 57 (45–67) | 63.5 (52–72) | 55 (44–65) | <0.001 |
| Male, n (%) | 666 (54.5) | 151 (59.0) | 515 (53.3) | 0.105 |
| BMI, kg/m2 | 22 (19.6–24.7) | 22.3 (19.9–25.0) | 21.9 (19.6–24.6) | 0.395 |
| Pre-existing clinical conditions | ||||
| Hypertension, n (%) | 252 (20.6) | 81 (31.6) | 171 (17.7) | <0.001 |
| Diabetes mellitus, n (%) | 121 (9.9) | 52 (20.3) | 69 (7.1) | <0.001 |
| Chronic kidney disease, n (%) | 26 (2.1) | 21 (8.2) | 5 (0.5) | <0.001 |
| Cerebrovascular disease, n (%) | 127 (10.4) | 50 (19.5) | 77 (8.0) | <0.001 |
| Chronic obstructive pulmonary disease, n (%) | 35 (2.9) | 18 (7.0) | 17 (1.8) | <0.001 |
| Coronary artery disease, n (%) | 53 (4.3) | 24 (9.4) | 29 (3.0) | <0.001 |
| Heart failure, n (%) | 31 (2.5) | 22 (8.6) | 9 (0.9) | <0.001 |
| Cancer, n (%) | 227 (18.6) | 50 (19.5) | 177 (18.3) | 0.659 |
| Sepsis, n (%) | 98 (8.0) | 70 (27.3) | 28 (2.9) | <0.001 |
| Admission type, n (%) | <0.001 | |||
| Elective surgical, n (%) | 863 (70.6) | 84 (32.8) | 779 (80.6) | |
| Emergency surgical, n (%) | 83 (6.8) | 33 (12.9) | 50 (5.2) | |
| Medical, n (%) | 276 (22.6) | 139 (54.3) | 137 (14.2) | |
| Baseline serum creatinine, mg/dL | 0.78 (0.64–0.96) | 0.76 (0.58–1.09) | 0.79 (0.65–0.94) | 0.949 |
| Baseline eGFR, mL/min/1.73 m2 | 119.4 (97.6–145.4) | 122.9 (83.3–158.7) | 118.7 (100.4–142.9) | 0.950 |
| Parameters at ICU admission | ||||
| sCr, mg/dL | 0.87 (0.72–1.07) | 0.97 (0.72–1.55) | 0.85 (0.72–1.02) | <0.001 |
| NT-proBNP, pg/mL | 97.1 (29.4–464.4) | 871.0 (225.8–2919.3) | 66.2 (23.7–206.2) | <0.001 |
| sCysC, mg/L | 0.78 (0.61–1.06) | 1.15 (0.83–1.85) | 0.75 (0.58–0.94) | <0.001 |
| APACHE Ⅱ score | 7 (4–10) | 11 (8–16) | 6 (4–9) | <0.001 |
| UP, mL/kg/hour | 1.67 (1.20–2.26) | 1.37 (0.89–2.20) | 1.73 (1.26–2.27) | <0.001 |
| Outcomes | ||||
| ICU mortality, n (%) | 40 (3.3) | 33 (12.9) | 7 (0.7) | <0.001 |
| In-hospital mortality, n (%) | 53 (4.3) | 40 (15.6) | 13 (1.3) | <0.001 |
| ICU stay, days | 2 (2–4) | 6 (3–13.3) | 2 (2–3) | <0.001 |
| Hospital stay, days | 16 (12–23) | 22 (13–33.3) | 15 (11–21) | <0.001 |
| ICU costs, CNY | 39 461.7 (28 966.2–59 437.2) | 66 140.1 (36 526.0–131 843.8) | 37 667.5 (27 881.5–48 238.4) | <0.001 |
| Total costs, CNY | 58 295.3 (44 201.6–98 602.8) | 128 945.6 (71 506.8–199 685.4) | 52 773.8 (40 856.2–78 718.9) | <0.001 |
Continuous variables are expressed as mean±SD or median (25th to 75th percentile, IQR). Categorical variables are expressed as a n (%).
AKI, acute kidney injury; BMI, body mass index; CNY, Chinese yuan; eGFR, estimated glomerular filtration rate; ICU, intensive care unit; NT-proBNP, N-terminal pro-B-type natriuretic peptide; APACHE Ⅱ score, Acute Physiology and Chronic Health Evaluation Ⅱ score; sCr, serum creatinine; sCysC, serum cystatin C; UP, urine production first 24 hours after admission.