Prognosis of Ischemic Stroke Patients Undergoing Endovascular Thrombectomy is Influenced by Systemic Inflammatory Index Through Malignant Brain Edema

Figures & data

Figure 1 Flow chart of the inclusion of the study population.

Table 1 Baseline Clinical Characteristics of the MCE and No MCE Patients

Variables	ALL (n=675)	No MCE (n=543)	MCE (n=132)	P
Demographic characteristics
Age, y, mean (SD)	67.1(11.4)	66.9(11.5)	68.3(11.0)	0.171
Female sex, n (%)	273(40.4)	216(39.8)	57(43.2)	0.475
Past Medical History, n (%)
Hypertension	445(65.9)	343(63.2)	102(77.3)	0.002
Diabetes mellitus	112(16.6)	86(15.8)	26(19.7)	0.285
Atrial fibrillation	327(48.4)	256(47.1)	71(53.8)	0.171
Clinical data
Admission SBP, median (IQR)	149(130–161)	149(130–161)	149(130–163)	0.732
Admission DBP, median (IQR)	80(73–90)	80(74–90)	82(70–91)	0.880
Admission NIHSS, median, (IQR)	15(12–19)	14(12–18)	18(16–21)	<0.001
Admission ASPECT, median, (IQR)	9(7–10)	9(8–10)	7(5–9)	<0.001
IV-rtPA, n (%)	129(19.1)	98(18.0)	31(23.5)	0.154
Occlusion site, n (%)
ICA	312(46.2)	218(40.1)	94(71.2)	<0.001
MCA-M1	363(53.8)	325(59.9)	38(28.8)
TOAST type, n (%)
LAA	230(34.1)	195(35.9)	35(26.5)	0.061
CE	368(54.5)	284(52.3)	84(63.6)
Others	77(11.4)	64(11.8)	13(9.8)
Procedure process
OTP, median (IQR)	280(220–345)	280(220–346)	280(223–343)	0.999
OTR,median (IQR)	350(286–429)	347(283–420)	370(313–441)	0.036
Collateral, n (%)
Grade 0	115(17.0)	56(10.3)	59(44.7)	<0.001
Grade 1	232(34.4)	179(33.0)	53(40.2)
Grade 2	328(48.6)	308(56.7)	20(15.2)
mTICI (2b/3), n (%)	540(80.0)	458(84.3)	82(62.1)	<0.001
Laboratory data on admission
FBG, mmol/L,mean (SD)	7.2(5.1)	6.9(5.3)	8.5(3.5)	0.001
Leukocytes, 103/μL, mean (SD)	10.6(4.1)	10.1(3.4)	12.7(5.7)	<0.001
Neutrophils, 103/μL, mean (SD)	8.9(3.8)	8.3(3.2)	11.1(5.3)	<0.001
Lymphocytes, 103/μL, mean (SD)	1.1(0.6)	1.2(0.6)	0.9(0.5)	<0.001
Platelets,103/μL,mean (SD)	171.6(60.4)	173.0(61.2)	165.8(56.7)	0.222
SII index, 103/μ, mean (SD)	1.75(1.47)	1.57(1.30)	2.46(1.86)	<0.001
90d mRS ≤ 2, n (%)	325(48.1)	313(57.6)	12(9.1)	<0.001
90d Death, n(%)	141(20.9)	59(10.9)	82(62.1)	<0.001

Abbreviations: MCE, Malignant cerebral edema; SD, standard deviation; IQR, interquartile range; SBP, systolic blood pressure; DBP, diastolic blood pressure; NIHSS, National Institutes of Health Stroke Scale; ASPECT, Alberta Stroke Program Early CT; IV-rtPA, intravenous alteplase; TOAST, the Trial of ORG 10172 in Acute Stroke Treatment; LAA, large-artery atherosclerosis; CE, cardioembolic; ICA, internal carotid artery; MCA-M1, M1 segment of the middle cerebral artery; OTP, onset-to-puncture time; OTR, onset-to-reperfusion time; mTICI, modified Thrombolysis in Cerebral Infarction; FBG, fasting blood glucose; SII, systemic immune inflammatory index; mRS modified Rankin Scale.

Table 2 Multivariate Analysis of Different Variables in MCE Patients

Independent Variable	Adjusted OR	95% CI	P-value
Hypertension	1.743	0.999–3.041	0.050
Admission NIHSS	1.059	1.012–1.108	0.012
Admission ASPECT	0.750	0.670–0.840	<0.001
Collateral
Grade 0		Reference
Grade1	0.524	0.296–0.928	0.027
Grade2	0.175	0.089–0.345	<0.001
Occlusion site
ICA		Reference
MCA-M1	0.356	0.217–0.585	<0.001
OTR	1.000	0.999–1.002	0.900
mTICI (2b/3)	0.388	0.229–0.658	<0.001
FBG	1.037	1.002–1.074	0.041
SII	1.209	1.034–1.413	0.017

Abbreviations: OR, odds ratio; CI, confidence interval; NIHSS, National Institutes of Health Stroke Scale; ASPECT, Alberta Stroke Program Early CT; ICA, internal carotid artery; MCA-M1, M1 segment of the middle cerebral artery; OTR, onset-to-reperfusion time; mTICI, modified Thrombolysis in Cerebral Infarction; FBG, fasting blood glucose; SII, systemic immune inflammatory index.

Table 3 Baseline Clinical Characteristics for Different Prognosis

Variables	mRS≤2(n=325)	mRS>2 (n=350)	P
Demographic characteristics
Age, y, mean (SD)	63.8(11.3)	70.2(10.7)	<0.001
Female sex, n (%)	105(32.3)	168(48.0)	<0.001
Past Medical History, n (%)
Hypertension	192(59.1)	253(72.3)	<0.001
Diabetes mellitus	36(11.1)	76(21.7)	<0.001
Atrial fibrillation	120(36.9)	207(59.1)	<0.001
Clinical data
Admission SBP, median (IQR)	146(129–160)	150(134–165)	0.016
Admission DBP, median (IQR)	80(73–90)	80(74–91)	0.635
Admission NIHSS, median, (IQR)	14(11–17)	17(14–20)	<0.001
Admission ASPECT,median, (IQR)	9(8–10)	8(7–9)	<0.001
IV-rtPA, n (%)	65(20.0)	64(18.3)	0.571
Occlusion site, n (%)
ICA	118(36.3)	194(55.4)	<0.001
MCA-M1	207(63.7)	156(44.6)
TOAST type, n (%)
LAA	134(41.2)	96(27.4)	<0.001
CE	143(44.0)	225(64.3)
Others	48(14.8)	29(8.3)
Procedure process
OTP, median (IQR)	284(220–347)	270(220–344)	0.644
OTR,median (IQR)	347(280–415)	355(294–435)	0.106
Collateral, n (%)
Grade 0	13(4.0)	102(29.1)	<0.001
Grade 1	93(28.6)	139(39.7)
Grade 2	219(67.4)	109(31.2)
mTICI (2b/3), n (%)	294(90.5)	246(70.3)	<0.001
Laboratory data on admission
FBG, mmol/L,mean (SD)	6.4(6.1)	8.0(3.6)	<0.001
SII <2.14, n (%)	274(84.3)	216(61.7)	<0.001

Abbreviations: mRS, modified Rankin Scale; SD, standard deviation; IQR, interquartile range; SBP, systolic blood pressure; DBP, diastolic blood pressure; NIHSS, National Institutes of Health Stroke Scale; ASPECT, Alberta Stroke Program Early CT; IV-rtPA, intravenous alteplase; TOAST, the Trial of ORG 10172 in Acute Stroke Treatment; LAA, large-artery atherosclerosis; CE, cardioembolic; ICA, internal carotid artery; MCA-M1, M1 segment of the middle cerebral artery; OTP, onset-to-puncture time; OTR, onset-to-reperfusion time; mTICI, modified Thrombolysis in Cerebral Infarction; FBG, fasting blood glucose; SII, systemic immune inflammatory index.

Table 4 Multivariate Analysis of Factors Influencing 90-Day Prognosis

Independent Variable	Adjusted OR	95% CI	P-value
Age	0.992	0.967–1.018	0.544
Female:Male	1.068	0.624–1.826	0.811
Hypertension	1.922	1.063–3.477	0.031
Diabetes mellitus	0.947	0.497–1.806	0.869
Atrial fibrillation	0.745	0.430–1.293	0.295
Admission SBP	0.998	0.988–1.009	0.755
Admission NIHSS	1.058	1.011–1.107	0.015
Admission ASPECT	0.750	0.669–0.840	<0.001
Collateral
Grade 0		Reference
Grade1	0.483	0.265–0.883	0.018
Grade2	0.159	0.079–0.322	<0.001
Occlusion site
ICA		Reference
MCA-M1	0.362	0.217–0.604	<0.001
mTICI (2b/3)	0.349	0.201–0.605	<0.001
FBG	1.040	1.002–1.079	0.037
SII (≥2.14)	3.639	2.197–6.027	<0.001

Abbreviations: OR, odds ratio; CI, confidence interval; SBP, systolic blood pressure; NIHSS, National Institutes of Health Stroke Scale; ASPECT, Alberta Stroke Program Early CT; ICA, internal carotid artery; MCA-M1, M1 segment of the middle cerebral artery; mTICI, modified Thrombolysis in Cerebral Infarction; FBG, fasting blood glucose; SII, systemic immune inflammatory index.

Figure 2 Distribution of modified Rankin Scale (MRS) scores at day 90 according to grouping of SII cutoff values.

Figure 3 Analysis of the mediating effect of postoperative cerebral edema on the relationship between SII and functional outcome.