Table 2.
Study characteristics of most frequently studied urine biomarkers for CKD outcomes
| Urine Biomarker | N Studies Available for Pooling | N Studies by Outcome Typea | Pooled N of Participants | Clinical Settings Studied | Diabetes Status of Studies Available | Pooled Relative Risk (95% CI) | I2b | Qb |
|---|---|---|---|---|---|---|---|---|
| KIM-1 | 19 | Incident CKD (5); incident ESKD (4); composite (12) | 22,569 | 4 clinical trials, 15 outpatient cohorts | 5 cohorts with T2DM only, 2 cohorts with T1DM only, 2 cohorts without DM, 10 cohorts of mixed DM status | Overall 1.10 (1.05 to 1.16); incident CKD 1.09 (1.03 to 1.15); incident ESKD 1.19 (1.07 to 1.32); composite 1.07 (1.00 to 1.15) | 26.02% | 24.33 |
| NGAL | 19 | Incident CKD (3); incident ESKD (6); composite (10) | 25,101 | 3 clinical trials, 2 inpatient cohorts, 14 outpatient cohorts | 4 cohorts with T2DM only, 3 cohorts with DM, 12 cohorts of mixed DM status | Overall 1.12 (1.06 to 1.19); incident CKD 1.03 (0.98 to 1.08); incident ESKD 1.39 (1.10 to 1.74); composite 1.10 (1.01 to 1.19) | 71.93% | 64.13 |
| L-FABP | 8 | Incident ESKD (4); composite (4) | 5372 | 2 inpatient cohorts, 6 outpatient cohorts | 3 cohorts with T2DM, 5 cohorts of mixed DM status | Overall 1.25 (1.01 to 1.54); incident ESKD 1.16 (0.66 to 1.55); composite 1.44 (0.94 to 2.21) | 75.38% | 28.43 |
| α1M | 8 | Incident CKD (2); composite (6) | 7966 | 3 clinical trials, 5 outpatient cohorts | 3 cohorts without DM, 5 cohorts of mixed DM status | Overall 1.16 (1.02 to 1.31); incident CKD 1.04 (0.89 to 1.22); composite 1.22 (1.02 to 1.46) | 35.71% | 10.89 |
| UMOD | 8 | Incident CKD (3); Iincident ESKD (1); composite (5) | 7361 | 3 clinical trials, 5 outpatient cohorts | 1 cohort with T2DM only, 3 cohorts without DM, 4 cohorts of mixed DM status | Overall 0.91 (0.74 to 1.11); incident CKD 1.13 (0.87 to 1.45); incident ESKD 0.84 (0.31 to 2.27); composite 0.78 (0.60 to 1.02) | 76.44% | 29.71 |
| EGF | 8 | Incident CKD (1); composite (7) | 7362 | All outpatient cohorts | 1 cohort with T2DM only, 3 cohorts without DM, 1 cohort of mixed DM status | Overall 0.73 (0.53 to 0.99) incident CKD 1.95 (0.92 to 4.13); composite 0.73 (0.53 to 0.99) | 91.43% | 70.00 |
| IL-18 | 6 | Composite outcomes only | 5189 | 3 clinical trials, 3 outpatient cohorts | 1 cohort with T2DM only, 2 cohorts without DM, 3 cohorts of mixed DM status | Overall/composite outcomes only 1.20 (1.07 to 1.36) | 0.00% | 3.86 |
| β2M | 6 | Incident CKD (1); incident ESKD (1); composite (4) | 15,852 | 3 clinical trials, 3 outpatient cohorts | 3 cohorts without DM, 3 cohorts of mixed DM status | Overall 1.23 (0.94 to 1.63) incident CKD 1.70 (0.57 to 5.10); incident ESKD 0.97 (0.83 to 1.13); composite 1.01 (0.93 to 1.09) | 0.00% | 1.36 |
| NAG | 6 | Incident ESKD (2); composite (4) | 3941 | 1 inpatient cohort, 5 outpatient cohorts | 2 cohorts with T2DM only, 4 cohorts of mixed DM status | Overall 1.09 (0.94 to 1.28) incident ESKD 1.05 (0.84 to 1.32); composite 1.13 (0.91 to 1.39) | 63.58% | 13.73 |
| MCP-1 | 6 | Composite outcomes only | 5553 | 2 clinical trials, 4 outpatient cohorts | 3 cohort swith T2DM only, 2 cohorts without DM, 1 cohort of mixed DM status | Overall/composite outcomes only 1.05 (0.71 to 1.53) | 91.1% | 56.33 |
| YKL-40c | 3 | Composite outcomes only | 3132 | 2 clinical trials, 1 outpatient cohort | 1 cohort with T2DM only, 2 cohorts without DM | Overall/composite outcomes only 1.12 (0.98 to 1.29) | 0.00% | 0.46 |
| CKD273 | 2 | Incident CKD only | 3101 | 2 outpatient cohorts | 2 cohorts of mixed DM status | Overall/incident CKD only 1.45 (0.92 to 2.31) | 81.43% | 5.39 |
KIM-1, kidney injury molecule-1; T2DM, type 2 diabetes mellitus; L-FABP, liver-type fatty acid binding protein; α1M, alpha-1-microglobulin; UMOD, uromodulin; EGF, epidermal growth factor; β2M, beta 2 microglobulin NAG, N-acetyl-β-D-glucosaminidase; ; MCP-1, monocyte chemoattractant protein-1.
a
Number of studies not additive as studies may report multiple outcomes of interest.
b
Results in reference to overall pooled RR.
c
Also known as Chitinase 3-like protein 1.