Table 3. Patient outcomes stratified by AKIN classification of AKI.

	No AKI (n = 3,985)		AKIN stage 1 (n = 455)		AKIN stage 2 (n = 56)		AKIN stage 3 (n = 76)
	mean ± SD/count	column	mean ± SD/count	column	mean ± SD/count	column	mean ± SD/count	column
Age, years	66.6 ± 11.0		68.6 ± 11.0a		67.7 ± 11.5		70.2 ± 9.6a
Additive EuroSCORE	4.9 ± 3.1		6.2 ± 3.6a		7.3 ± 3.9a		7.5 ± 3.7a, b
Median length of stay, days	7 (IQR 4)		9 (IQR 8)c		11 (IQR 13)c		17 (IQR 34)c
Died as inpatient	87	2.2%	34c	7.5%	7c	12.5%	38c	50%

AKIN stage 1: increase in serum creatinine ≥26.5 μmol/l (0.3 mg/dl) or increase to ≥150–199% from baseline. AKIN stage 2: increase in serum creatinine to 200–299% (>2- to 2.9-fold) from baseline. AKIN stage 3: increase in serum creatinine to ≥300% (≥3-fold) from baseline or serum creatinine ≥354 μmol/l (4.0 mg/dl) with an acute rise of at least 44.25 μmol/l (0.5 mg/dl) or initiation of RRT. Stepwise increases in median length of stay and inpatient mortality were noted with increasing AKIN grade.

^ap < 0.05 when compared to no AKI

^bp < 0.05 when compared to AKIN 1

^cp < 0.001 all groups.