Table 4.

Multivariable analyses of independent effects of multiple biomarkers on clinical outcomes

Biomarker	Adjusted HR (95% CI)	P-value
Renal recovery
IL-8	0.80 (0.70–0.91)	<0.001
TNFR-I	0.63 (0.50–0.79)	<0.001
Mortality
IL-8	1.26 (1.14–1.39)	<0.001
MIF	1.18 (1.08–1.28)	<0.001
TNFR-I	1.26 (1.02–1.56)	0.03

Only significant results for time to renal recovery and mortality from Cox models are shown. All models were adjusted for differences in age; race; sex; Charlson comorbidity score without age; history of chronic hypoxemia, liver disease and immunocompromised state; premorbid serum creatinine; nephrotoxic cause of AKI; diagnosis of sepsis; presence of oliguria at initiation of RRT; use of mechanical ventilation, intensity of RRT and other biomarkers. Models were not adjusted for APACHE II score due to multicolinearity between APACHE II score and biomarkers.

For time to renal recovery model, a HR >1 indicates that per natural log increase in biomarker concentration is associated with faster recovery and <1 indicates slower recovery. For time to death, a HR of >1 indicates that per natural log increase in biomarker concentration is associated with shorter time to death and <1 indicates longer time to death.

The models included 682 subjects due to missing premorbid creatinine data in 134 subjects and DR-5 marker levels in 1 subject. Models were not constructed for IL-1β, TNF and GM-CSF due to high censoring of biomarker data.

IL, interleukin; MIF, macrophage migration inhibitory factor; TNFR-I, tumor necrosis factor receptor-I.