Table 2. Baseline characteristics.

Characteristics	No Early AKI (N = 847)	Early AKI(N = 54)	p-value
Age, in years [median (IQR)]	39 (26–52)	42 (26–57)	0.4
Age >55 (%)	20	33	0.04
Male gender (%)	72	83	0.08
Injury Severity Score [mean (SD)]	23 (13)	26 (14)	0.5
Time from injury to emergency room arrival [mean (SD)] (in minutes)	78 (15)	79 (17)	0.4
Baseline creatinine [median (IQR)] (in mg/dL)*	1.1 (0.9–1.3)	1.4 (1.0–1.6)	<0.0001
Glasgow coma score [median (IQR)]	15 (3–15)	14 (3–15)	0.3
Mean blood pressure [mean (SD)] (in mm Hg)	124 (35)	115 (38)	0.4
Diabetes mellitus (%)	5.2%	7.4%	0.5
Hypertension (%)	6.0	7.4	0.6
Maximum head AIS (%)			0.2
1–2	12	0
3	41	28
4	31	39
5	16	33
Maximum Chest AIS (%)			0.05
1–2	11	13
3	36	29
4	40	31
5	13	27
Maximum ABD AIS (%)			0.002
1–2	50	39
3	28	30
4	17	8
5	5	19

AKI: Acute kidney injury; IQR: Inter-quartile range; SD: Standard deviation; ED: Emergency department;

AIS: Abbreviated injury score.

^*Lowest creatinine within 24 hours.