Predictive Values of White Blood Cell Count in Peripheral Blood at Admission on In-Hospital Complications and 90-Day Outcomes of Patients with Aneurysmal Subarachnoid Hemorrhage: Insights from the LongTEAM Registry

Figures & data

Table 1 Baseline Information

Characteristics	Total	WBC^a Level				p^c
		Q1 (<9.87)	Q2 (9.87–12.40)	Q3 (12.40–15.41)	Q4 (≥15.41)
No. of patients	988	246	248	246	248
Age, years, mean±SD	54.8±11.0	56.3±11.2	54.8±10.6	54.7±10.7	53.5±11.5	0.051
Female, n (%)	583 (59.0)	144 (58.5)	147 (59.3)	143 (58.1)	149 (60.1)	0.973
Hypertension, n (%)	581 (58.8)	146 (59.3)	150 (60.5)	129 (52.4)	156 (62.9)	0.104
Hyperlipidemia, n (%)	78 (7.9)	22 (8.9)	21 (8.5)	17 (6.9)	18 (7.3)	0.813
Diabetes mellitus, n (%)	92 (9.3)	24 (9.8)	30 (12.1)	15 (6.1)	23 (9.3)	0.148
Heart disease, n (%)	74 (7.5)	16 (6.5)	17 (6.9)	15 (6.1)	26 (10.5)	0.223
Current smoking, n (%)	263 (26.6)	58 (23.6)	70 (28.2)	68 (27.6)	67 (27.0)	0.649
Current drinking, n (%)	198 (20.0)	57 (23.2)	49 (19.8)	44 (17.9)	48 (19.4)	0.512
Posterior circulation, n (%)	106 (10.7)	29 (11.8)	26 (10.5)	23 (9.3)	28 (11.3)	0.832
Maximum diameter of aneurysm^b, mean±SD	6.56±5.40	6.58±6.42	6.57±5.60	6.77±6.60	6.33±3.64	0.917
Early seizures, n (%)	54 (5.5)	10 (4.1)	14 (5.6)	7 (2.8)	23 (9.3)	0.011
Early loss of consciousness, n (%)	304 (30.8)	42 (17.1)	60 (24.2)	77 (31.3)	125 (50.4)	<0.001
WFNS grade 4–5, n (%)	222 (22.5)	26 (10.6)	37 (14.9)	56 (22.8)	103 (41.5)	<0.001
mFS grade 3–4, n (%)	718 (72.7)	155 (63.0)	176 (71.0)	178 (72.4)	209 (84.3)	<0.001
Graeb score 5–12, n (%)	84 (8.5)	9 (3.7)	13 (5.2)	20 (8.1)	42 (16.9)	<0.001
SEBES score 3–4, n (%)	491 (49.7)	83 (33.7)	118 (47.6)	122 (49.6)	168 (67.7)	<0.001
Acute hydrocephalus, n (%)	387 (39.2)	73 (29.7)	78 (31.5)	104 (42.3)	132 (53.2)	<0.001
Neutrophil-to-lymphocyte ratio, median (IQR)	11.69 (7.54–17.40)	6.98 (4.44–11.48)	10.22 (7.17–14.46)	13.99 (9.44–19.78)	15.88 (10.71–23.58)	<0.001
Treatment modality						0.959
Surgical clipping, n (%)	507 (51.3)	123 (50.0)	127 (51.2)	129 (52.4)	128 (51.6)
Endovascular coiling, n (%)	481 (48.7)	123 (50.0)	121 (48.8)	117 (47.6)	120 (48.4)

Notes: ^aunit of measurement: 10⁹/ L. ^bUnit of measurement: mm. ^cDenotes significance after applying a Bonferroni correction, significance was set at p<0.00833.

Abbreviations: WFNS, world federation of neurological societies; mFS, modified Fisher; SEBES, subarachnoid hemorrhage early brain edema score.

Table 2 Adjusted Odds Ratios of In-Hospital Complications and Functional Outcomes According to WBC Levels at Admission

Variables	WBC^a Level	No.	Model 1			Model 2
			Events, n (%)	Adjusted OR (95% CI)	p	Adjusted OR (95% CI)	p
Cardiac event	Q1	246	88 (35.8)	–	–	–	–
	Q2	248	91 (36.7)	1.11 (0.76–1.62)	0.585	1.01 (0.69–1.48)	0.963
	Q3	246	94 (38.2)	1.20 (0.82–1.75)	0.345	1.01 (0.68–1.49)	0.980
	Q4	248	103 (41.5)	1.45 (0.99–2.10)	0.054	1.01 (0.66–1.53)	0.971
DCI	Q1	246	51 (20.7)	–	–	–	–
	Q2	248	64 (25.8)	1.38 (0.90–2.11)	0.141	1.27 (0.83–1.97)	0.275
	Q3	246	72 (29.3)	1.64 (1.08–2.50)	0.021	1.41 (0.92–2.18)	0.118
	Q4	248	81 (32.7)	1.99 (1.32–3.02)	0.001	1.43 (0.90–2.26)	0.132
Intracranial infection	Q1	246	31 (12.6)	–	–	–	–
	Q2	248	28 (11.3)	0.83 (0.48–1.48)	0.528	0.82 (0.45–1.47)	0.504
	Q3	246	36 (14.6)	1.15 (0.67–2.00)	0.611	1.11 (0.63–1.97)	0.714
	Q4	248	30 (12.1)	0.93 (0.53–1.64)	0.798	0.85 (0.45–1.60)	0.613
Stress ulcer bleeding	Q1	246	46 (18.7)	–	–	–	–
	Q2	248	58 (23.4)	1.39 (0.90–2.16)	0.139	1.27 (0.81–2.00)	0.292
	Q3	246	48 (19.5)	1.11 (0.70–1.74)	0.660	0.89 (0.55–1.43)	0.621
	Q4	248	57 (23.0)	1.41 (0.90–2.19)	0.130	0.86 (0.52–1.43)	0.567
Urinary tract infection	Q1	246	6 (2.4)	–	–	–	–
	Q2	248	5 (2.0)	0.85 (0.26–2.86)	0.798	0.81 (0.24–2.76)	0.732
	Q3	246	5 (2.0)	0.88 (0.26–2.92)	0.829	0.88 (0.25–3.16)	0.850
	Q4	248	12 (4.8)	2.21 (0.81–6.05)	0.124	1.91 (0.59–6.19)	0.280
Anemia	Q1	246	75 (30.5)	–	–	–	–
	Q2	248	71 (28.6)	0.94 (0.62–1.41)	0.750	0.85 (0.56–1.30)	0.457
	Q3	246	76 (30.9)	1.05 (0.69–1.58)	0.834	0.84 (0.54–1.29)	0.428
	Q4	248	93 (37.5)	1.50 (0.99–2.25)	0.051	0.94 (0.60–1.49)	0.792
Hypoproteinemia	Q1	246	73 (29.7)	–	–	–	–
	Q2	248	83 (33.5)	1.28 (0.86–1.92)	0.226	1.16 (0.77–1.76)	0.471
	Q3	246	84 (34.1)	1.31 (0.88–1.97)	0.184	1.08 (0.71–1.64)	0.732
	Q4	248	105 (42.3)	2.07 (1.39–3.08)	<0.001	1.30 (0.83–2.02)	0.253
Pneumonia	Q1	246	49 (19.9)	–	–	–	–
	Q2	248	69 (27.8)	1.67 (1.09–2.56)	0.019	1.45 (0.93–2.27)	0.104
	Q3	246	75 (30.5)	1.91 (1.25–2.91)	0.003	1.39 (0.88–2.19)	0.156
	Q4	248	116 (46.8)	4.16 (2.75–6.31)	<0.001	2.06 (1.30–3.29)	0.002
MCVT	Q1	246	57 (23.2)	–	–	–	–
	Q2	248	60 (24.2)	1.16 (0.75–1.78)	0.509	1.10 (0.71–1.72)	0.664
	Q3	246	64 (26.0)	1.29 (0.84–1.98)	0.250	1.17 (0.74–1.83)	0.515
	Q4	248	71 (28.6)	1.55 (1.01–2.37)	0.043	1.15 (0.71–1.88)	0.567
DVT	Q1	246	16 (6.5)	–	–	–	–
	Q2	248	21 (8.5)	1.41 (0.72–2.80)	0.320	1.45 (0.72–2.91)	0.301
	Q3	246	20 (8.1)	1.34 (0.68–2.68)	0.400	1.42 (0.68–2.98)	0.350
	Q4	248	28 (11.3)	2.01 (1.05–3.85)	0.036	1.98 (0.93–4.20)	0.077
Lipid metabolism disorder	Q1	246	64 (26.0)	–	–	–	–
	Q2	248	57 (23.0)	0.86 (0.57–1.30)	0.472	0.86 (0.56–1.31)	0.472
	Q3	246	67 (27.2)	1.09 (0.73–1.62)	0.693	1.09 (0.72–1.66)	0.681
	Q4	248	57 (23.0)	0.87 (0.57–1.31)	0.496	0.90 (0.57–1.43)	0.654
Mortality at discharge	Q1	246	4 (1.6)	–	–	–	–
	Q2	248	3 (1.2)	0.78 (0.17–3.54)	0.748	0.86 (0.57–1.31)	0.492
	Q3	246	4 (1.6)	1.04 (0.26–4.24)	0.954	0.98 (0.64–1.50)	0.909
	Q4	248	5 (2.0)	1.33 (0.35–5.05)	0.677	1.21 (0.76–1.92)	0.422
Unfavorable outcome at discharge	Q1	246	89 (36.2)	–	–	–	–
	Q2	248	88 (35.5)	1.04 (0.71–1.53)	0.832	0.86 (0.57–1.31)	0.493
	Q3	246	102 (41.5)	1.37 (0.94–2.01)	0.103	0.98 (0.64–1.50)	0.922
	Q4	248	137 (55.2)	2.72 (1.85–4.00)	<0.001	1.21 (0.76–1.92)	0.420
90-day unfavorable outcome	Q1	246	28 (11.4)	-	-	-	-
	Q2	248	29 (11.7)	1.16 (0.65–2.04)	0.620	0.92 (0.51–1.68)	0.786
	Q3	246	51 (20.7)	2.40 (1.43–4.05)	0.001	1.60 (0.91–2.80)	0.102
	Q4	248	73 (29.4)	4.30 (2.59–7.15)	<0.001	1.81 (1.02–3.20)	0.042

Notes: Model 1: adjusted for age, sex, and treatment modality. Model 2: adjusted for Model 1+Early loss of consciousness+WFNS grade 4–5+mFS grade 3–4+Graeb score 5–12+SEBES score 3–4+Acute hydrocephalus+Neutrophil-to-lymphocyte ratio. ^aUnit of measurement: 10⁹/ L.

Abbreviations: DCI, delayed cerebral ischemia; MCVT, muscular calf vein thrombosis; DVT, deep vein thrombosis.

Figure 1 Adjusted odds ratios of (A) pneumonia and (B) 90-day unfavorable outcomes according to baseline WBC level. The reference is the Q1 of the baseline WBC level (9.87×10⁹/L). Data were fitted using a logistic regression model of the restricted cubic spline with five knots (the 5th, 25th, 50th, 75th, 95th percentiles) for baseline WBC level, adjusting for potential covariates.

Figure 2 Kaplan–Meier curves for in-hospital pneumonia.

Table 3 Subgroup Analysis of Association Between WBC Groups and In-Hospital Pneumonia

Subgroup	WBC Level	No. of Patients	Events, n (%)	Adjusted OR (95% CI)	p	p for Interaction
Age						0.040
≤55	Q1	118	18 (15.3)	–
	Q2	130	37 (28.5)	1.83 (0.92–3.62)	0.084
	Q3	129	25 (19.4)	0.94 (0.45–1.95)	0.862
	Q4	146	66 (45.2)	2.21 (1.10–4.41)	0.025
>55	Q1	128	31 (24.2)	–
	Q2	118	32 (27.1)	1.06 (0.58–1.95)	0.843
	Q3	117	50 (42.7)	1.75 (0.96–3.19)	0.067
	Q4	102	50 (49.0)	1.63 (0.85–3.12)	0.143
Sex						0.616
Male	Q1	102	20 (19.6)	–
	Q2	101	35 (34.7)	2.19 (1.08–4.45)	0.029
	Q3	103	32 (31.1)	1.70 (0.80–3.61)	0.168
	Q4	99	50 (50.5)	2.56 (1.16–5.62)	0.020
Female	Q1	144	29 (20.1)	–
	Q2	147	34 (23.1)	1.17 (0.64–2.13)	0.603
	Q3	143	43 (30.1)	1.29 (0.72–2.33)	0.399
	Q4	149	66 (44.3)	1.93 (1.06–3.53)	0.032
Current smoking						0.493
Yes	Q1	58	11 (19.0)	–
	Q2	70	20 (28.6)	2.03 (0.78–5.32)	0.148
	Q3	68	21 (30.9)	1.79 (0.65–4.92)	0.257
	Q4	67	38 (56.7)	4.10 (1.44–11.71)	0.008
No	Q1	188	38 (20.2)	–
	Q2	178	49 (27.5)	1.37 (0.82–2.31)	0.235
	Q3	178	54 (30.3)	1.38 (0.82–2.33)	0.225
	Q4	181	78 (43.1)	1.81 (1.06–3.10)	0.031
Hypertension						0.265
Yes	Q1	146	37 (25.3)	–
	Q2	150	43 (28.7)	1.05 (0.60–1.84)	0.855
	Q3	129	44 (34.1)	1.20 (0.67–2.14)	0.536
	Q4	156	83 (53.2)	1.86 (1.06–3.29)	0.032
No	Q1	100	12 (12.0)	–
	Q2	98	26 (26.5)	3.04 (1.34–6.91)	0.008
	Q3	117	31 (26.5)	2.67 (1.16–6.15)	0.021
	Q4	92	33 (35.9)	3.35 (1.34–8.35)	0.010
WFNS grade						0.314
1–3	Q1	220	36 (16.4)	–
	Q2	211	49 (23.2)	1.54 (0.93–2.54)	0.094
	Q3	190	48 (25.3)	1.63 (0.97–2.72)	0.065
	Q4	145	43 (29.7)	1.85 (1.06–3.22)	0.030
4–5	Q1	26	13 (50.0)	–
	Q2	37	20 (54.1)	1.26 (0.41–3.87)	0.689
	Q3	56	27 (48.2)	0.97 (0.33–2.83)	0.956
	Q4	103	73 (70.9)	2.81 (0.97–8.14)	0.057
Treatment modality						0.329
Surgical clipping	Q1	123	27 (22.0)	–
	Q2	127	45 (35.4)	1.70 (0.94–3.08)	0.080
	Q3	129	40 (31.0)	1.23 (0.67–2.27)	0.504
	Q4	128	67 (52.3)	2.38 (1.28–4.43)	0.006
Endovascular coiling	Q1	123	22 (17.9)	–
	Q2	121	24 (19.8)	1.28 (0.63–2.62)	0.499
	Q3	117	35 (29.9)	1.76 (0.87–3.54)	0.115
	Q4	120	49 (40.8)	1.87 (0.90–3.85)	0.092

Abbreviations: WBC, white blood cell; WFNS, world federation of neurological societies.

Table 4 Subgroup Analysis of Association Between WBC Groups and 90-Day Outcomes

Subgroup	WBC Level	No. of Patients	Events, n (%)	Adjusted OR (95% CI)	p	p for Interaction
Age						0.513
≤55	Q1	118	9 (7.6)	–
	Q2	130	7 (5.4)	0.42 (0.14–1.26)	0.123
	Q3	129	15 (11.6)	1.01 (0.39–2.63)	0.985
	Q4	146	33 (22.6)	1.24 (0.50–3.12)	0.642
>55	Q1	128	19 (14.8)	–
	Q2	118	22 (18.6)	1.15 (0.56–2.35)	0.700
	Q3	117	36 (30.8)	1.60 (0.80–3.22)	0.187
	Q4	102	40 (39.2)	1.73 (0.83–3.64)	0.146
Sex						0.932
Male	Q1	102	10 (9.8)	–
	Q2	101	13 (12.9)	1.16 (0.43–3.15)	0.766
	Q3	103	20 (19.4)	2.35 (0.87–6.36)	0.093
	Q4	99	29 (29.3)	2.39 (0.86–6.68)	0.096
Female	Q1	144	18 (12.5)	–
	Q2	147	16 (10.9)	0.85 (0.39–1.86)	0.691
	Q3	143	31 (21.7)	1.55 (0.76–3.15)	0.228
	Q4	149	44 (29.5)	1.85 (0.90–3.82)	0.097
Current smoking						0.724
Yes	Q1	58	5 (8.6)	–
	Q2	70	7 (10.0)	1.55 (0.36–6.63)	0.557
	Q3	68	14 (20.6)	2.95 (0.72–12.02)	0.132
	Q4	67	18 (26.9)	1.89 (0.45–7.90)	0.383
No	Q1	188	23 (12.2)	–
	Q2	178	22 (12.4)	0.92 (0.46–1.82)	0.803
	Q3	178	37 (20.8)	1.56 (0.82–2.96)	0.173
	Q4	181	55 (30.4)	2.19 (1.14–4.19)	0.018
Hypertension						0.436
Yes	Q1	146	21 (14.4)	–
	Q2	150	21 (14.0)	0.85 (0.42–1.73)	0.652
	Q3	129	29 (22.5)	1.41 (0.71–2.83)	0.329
	Q4	156	56 (35.9)	2.11 (1.08–4.13)	0.028
No	Q1	100	7 (7.0)	–
	Q2	98	8 (8.2)	1.48 (0.44–4.99)	0.527
	Q3	117	22 (18.8)	3.07 (1.02–9.26)	0.047
	Q4	92	17 (18.5)	2.23 (0.63–7.91)	0.212
WFNS grade						0.433
1–3	Q1	220	20 (9.1)	–
	Q2	211	19 (9.0)	1.06 (0.53–2.15)	0.869
	Q3	190	21 (11.1)	1.31 (0.64–2.66)	0.461
	Q4	145	21 (14.5)	1.84 (0.88–3.85)	0.107
4–5	Q1	26	8 (30.8)	–
	Q2	37	10 (27.0)	0.69 (0.21–2.28)	0.539
	Q3	56	30 (53.6)	2.52 (0.85–7.46)	0.094
	Q4	103	52 (50.5)	2.25 (0.79–6.43)	0.130
Treatment modality						0.573
Surgical clipping	Q1	123	15 (12.2)	–
	Q2	127	22 (17.3)	1.25 (0.57–2.72)	0.582
	Q3	129	33 (25.6)	1.84 (0.87–3.90)	0.110
	Q4	128	46 (35.9)	2.12 (0.99–4.54)	0.054
Endovascular coiling	Q1	123	13 (10.6)	–
	Q2	121	7 (5.8)	0.57 (0.20–1.62)	0.295
	Q3	117	18 (15.4)	1.37 (0.57–3.30)	0.485
	Q4	120	27 (22.5)	1.64 (0.67–4.05)	0.280

Abbreviations: WBC, white blood cell; WFNS, world federation of neurological societies.

Figure 3 (A) The timing of pneumonia formation. (B) Relationship between the length of stays and pneumonia. (C) Relationship between the number of complications and pneumonia. (D) Relationship between the total hospital charges and pneumonia (US dollar = 7.11 renminbi [updated on October 10, 2022]).