Table 1A.
Comparison of clinical risk prediction models for AKI in the ICU
| Kashani et al., 201311 | Malhotra et al., 201713 | Flechet et al., 201714 | |
|---|---|---|---|
| Sample size | n = 728 | n = 2017 | n = 4760 |
| Single- or multi-center | Multi-center | Single-center | Multi-center |
| Type of ICU | Mixed | Mixed | Mixed |
| Validation cohort | No | External validation | Internal validation |
| Physiologic data available | No | Yes (limited) | Yes |
| Biochemical data available | Yes | Yes | Yes |
| #Risk factors in final model | 9 (4 acute; 5 chronic) | 10 (5 acute; 5 chronic) | 13 (10 acute; 3 chronic) |
| Timeframe for examination of | Up to 5 days prior to study | Within 48h following ICU | Pre-admission; ICU |
| clinical variables | enrollment | admission | admission; Day 1 |
| AKI definition | ↑SCr ≥100% in 7d or UOP <0.5 ml/kg/h × >12h | ↑SCr ≥0.3 mg/dl in 48h or ≥50% in 7d | ↑SCr ≥0.3 mg/dl in 48h or ≥50% in 7d |
| RRT included in AKI definition | Yes | No | Yes |
| Timeframe for AKI determination | 12h from biospecimen collection | 7d from study enrollment | 7d from ICU admission |
| Baseline SCr determination | See below* | Mean of all SCr measurements 7-365d prior to admission | See below** |
| How missing baseline SCr was addressed | SCr at the time of enrollment | SCr at ICU admission utilized | SCr back-calculated*** |
| Incident AKI events (%) | 14.0 | 37.2 | 28.5 |
| PPV | NA | 23% for risk score ≥5 | 38% |
| AUC | 0.81 | 0.79 (internal validation) 0.81 (external validation) |
0.86–0.88 (discovery) 0.80–0.84 (validation) |
AKI = acute kidney injury; AUC = area under the receiver operating curve; ED = emergency department; eGFR = estimated glomerular filtration rate; ICU = intensive care unit; MDRD = modification of diet in renal disease; NA = not assessed; PPV = positive predictive value; RRT = renal replacement therapy; SCr = serum creatinine; UOP = urine output.
If at least 5 SCr values were available, the median of all values from 6 months to 6 days prior to enrollment was used. Otherwise, the lowest SCr value in the 5 days prior to enrollment was used.
The lowest SCr within 3 months prior to ICU admission was used for elective admissions, and the lowest SCr within 3 months to 1 week prior to ICU admission was used for patients transferred to the ICU from the emergency department.
Using an eGFR of 75 ml/min/1.73m2 (MDRD equation).