Table 2.

Selected baseline characteristics of TBI patients by 4 serum sodium classes.

Variable	Overall	Class 1	Class 2	Class 3	Class 4	p
N	852	603	173	13	63
Age	64.00 (44.00–78.00)	64.00 (46.00–79.00)	60.00 (35.00–74.00)	52.00 (30.00–64.00)	71.00 (56.00–81.00)	0.007
Gender (%)						0.564
Female	275 (32.28)	188 (31.18)	62 (35.84)	3 (23.08)	22 (34.92)
Male	577 (67.72)	415 (68.82)	111 (64.16)	10 (76.92)	41 (65.08)
Race (%)						0.548
White	460 (53.99)	335 (55.56)	83 (47.98)	6 (46.15)	36 (57.14)
Black	47 (5.52)	34 (5.64)	8 (4.62)	1 (7.69)	4 (6.35)
Others	345 (40.49)	234 (38.81)	82 (47.40)	6 (46.15)	23 (36.51)
GCS	15.00 (12.00–15.00)	15.00 (12.00–15.00)	15.00 (12.00–15.00)	15.00 (15.00–15.00)	14.00 (12.00–15.00)	0.022
SpO2, %	100 (97–100)	100 (97–100)	100 (98–100)	100 (97–100)	99 (96–100)	0.002
Glucose, mg/dl	137.57 ± 37.10	136.45 ± 36.53	144.28 ± 38.43	131.05 ± 35.69	131.23 ± 37.44	0.029
WBC, k/ul	11.67 ± 4.44	11.47 ± 4.32	12.75 ± 4.51	10.75 ± 3.73	10.87 ± 5.06	0.001
Diuretic use (%)						<0.001
No	574 (67.37)	428 (70.98)	92 (53.18)	7 (53.85)	47 (74.60)
Yes	278 (32.63)	175 (29.02)	81 (46.82)	6 (46.15)	16 (25.40)
Hypertension (%)						0.743
No	496 (58.22)	354 (58.71)	96 (55.49)	9 (69.23)	37 (58.73)
Yes	356 (41.78)	249 (41.29)	77 (44.51)	4 (30.77)	26 (41.27)
CKD (%)						0.049
No	779 (91.43)	557 (92.37)	159 (91.91)	11 (84.62)	52 (82.54)
Yes	73 (8.57)	46 (7.63)	14 (8.09)	2 (15.38)	11 (17.46)
Diabetes (%)						0.887
No	676 (79.34)	476 (78.94)	140 (80.92)	11 (84.62)	49 (77.78)
Yes	176 (20.66)	127 (21.06)	33 (19.08)	2 (15.38)	14 (22.22)
30-day mortality (%)						0.003
Alive	710 (83.33)	520 (86.24)	129 (74.57)	10 (76.92)	51 (80.95)
Dead	142 (16.67)	83 (13.76)	44 (25.43)	3 (23.08)	12 (19.05)
90-day mortality (%)						<0.001
Alive	702 (82.39)	518 (85.90)	124 (71.68)	10 (76.92)	50 (79.37)
Dead	150 (17.61)	85 (14.10)	49 (28.32)	3 (23.08)	13 (20.63)