Table 4.

Association between intensity of net ultrafiltration and time to mortality from Gray’s model

Characteristic	Adjusted hazard ratio (95% CI) by time intervala					p value
	5–15 days	15–23 days	23–39 days	39–91 days	91–365 days
High vs low UFNET	0.50 (0.35–0.71)	0.62 (0.46–0.82)	0.73 (0.55–0.97)	0.76 (0.56–1.04)	1.02 (0.71–1.47)	< 0.001
High vs moderate UFNET	0.53 (0.33–0.86)	0.69 (0.46–1.02)	0.75 (0.52–1.09)	0.77 (0.518–1.142)	1.16 (0.72–1.85)	0.039
Moderate vs low UFNET	0.98 (0.62–1.57)	0.87 (0.59–1.27)	0.996 (0.69–1.43)	1.01 (0.69–1.47)	0.844 (0.53–1.34)	0.91

Shown are adjusted hazard ratios estimated from Gray’s model for association between intensity of UF^NET and mortality for each time interval. Models included five time intervals and four time nodes with the default timing of nodes chosen by the statistical program based on the number of observations within each time interval. Hazard ratio < 1 suggests that UF^NET intensity is associated with lower mortality, and hazard ratio > 1 suggests UF^NET intensity is associated with higher mortality. p values reported are for the ranges of hazard ratios from the model

CI confidence interval, UF^NET net ultrafiltration, FO fluid overload, RRT renal replacement therapy, ICU intensive care unit

^aAdjusted for age, sex, race, body mass index, history of liver disease and sequela from liver disease, admission for liver transplantation, admission for surgery, baseline glomerular filtration rate, Acute Physiology and Chronic Health Evaluation III score, presence of sepsis, use of mechanical ventilation, percentage of FO before initiation of RRT, oliguria before initiation of RRT, time to initiation of RRT from ICU admission, mean arterial pressure on first day of RRT initiation, cumulative vasopressor dose and cumulative fluid balance during RRT, first RRT modality and duration of RRT