Red cell distribution width: a novel predictive biomarker for stroke risk after transient ischaemic attack

Figures & data

Figure 1. Flow chart for enrollment of the retrospective cohort study.

Table 1. The clinical characteristics of the study samples.

Characteristics	TIA (n = 103)	IS (n = 206)	HS (n = 51)	p^1-Value	p^2-Value	p^3-Value
Age (years), mean (SD)	58.94 (10.54)	58.94 (10.54)	58.88 (1.33)		.895	.884
Male, n (%)	59 (57)	118 (57)	39 (68)		.173	.142
Alcohol consumption, n (%)	19 (17)	42 (20)	9 (18)	.461	.554	.444
Current smoking, n (%)	23 (22)	67 (33)	12 (24)	.084	.521	.225
Hypertension, n (%)	64 (62)	145 (70)	39 (77)	.157	.258	.409
Diabetes mellitus, n (%)	26 (25)	82 (40)	19 (37)	.030*	.171	.476
Coronary heart disease, n (%)	11 (11)	28 (14)	5 (10)	.586	.561	.354
Time from onset to hospital (h)	19.52 (8.00)	21.20 (12.00)	24.42 (9.00)	.258	.000***	.000***
BMI, mean (SD)	24.97 (3.44)	25.36 (3.03)	24.42 (2.73)	.155	.485	.035*
SBP (mm Hg), mean (SD)	144.70 (23.46)	155.67 (25.09)	142.59 (20.12)	.000***	.759	.001**
DBP (mm Hg), mean (SD)	89.43 (15.45)	96.22 (14.94)	91.57 (13.02)	.000***	.195	.041*
WBC (10^9/Ul), mean (SD)	7.20 (2.04)	7.49 (1.95)	7.63 (1.86)	.130	.099	.593
N/L, mean (SD)	2.70 (1.46)	2.72 (1.47)	2.76 (1.38)	.016*	.283	.431
HGB (10^9/L), mean (SD)	141.06 (13.34)	141.79 (15.66)	143.92 (14.48)	.715	.178	.229
RBC (10^9/L), mean (SD)	4.68 (0.56)	4.74 (0.47)	4.71 (0.40)	.082	.364	.749
PLT (10^9/L), mean (SD)	232.56 (54.74)	236.11 (61.30)	208.45 (53.06)	.615	.038*	.009**
ALT (U/L), median (IQR)	19 (14–23)	18 (13–27)	19 (14–25)	.970	.557	.600
TBIL (μmol/L), mean (SD)	13.72 (4.92)	12.31 (5.91)	13.05 (5.35)	.038*	.029*	.574
CR (μmol/L), mean (SD)	70.56 (20.60)	68.66 (17.59)	67.28 (15.71)	.068	.011*	.002**
CRP (mg/L), median (IQR)	2.80 (1.10–4.70)	3.90 (1.70–7.20)	3.50 (1.60–6.70)	.002*	.048*	.711
FIB (g/L), median (IQR)	2.59 (2.18–2.93)	2.57 (2.31–3.12)	2.67 (2.30–3.03)	.111	.207	.945
ALB (g/L), median (IQR)	42.01 (40.0–43.8)	40.80 (39.18–42.65)	41.50 (38.80–43.3)	.001**	.038*	.950
UA (μmol/L), mean (SD)	365.24 (102.49)	344.44 (91.79)	352 (90.27)	.187	.216	.017*
HCY (mmol/L), mean (SD)	10.36 (4.50)	12.28 (6.96)	13.05 (8.19)	.040*	.044*	.589
TG (mmol/L), mean (SD)	1.53 (0.76)	1.65 (0.87)	1.79 (1.41)	.193	.250	.856
TC (mmol/L), mean (SD)	4.98 (1.05)	5.07 (1.17)	4.71 (0.89)	.660	.077	.023*
LDL (mmol/L), mean (SD)	3.04 (0.89)	3.20 (1.03)	2.93 (0.72)	.259	.562	.111
HDL (mmol/L), mean (SD)	1.29 (0.27)	1.24 (0.27)	1.18 (0.20)	.179	.018*	.164
FBG (mmol/L), mean (SD)	6.09 (1.79)	7.22 (2.97)	6.20 (1.95)	.000***	.934	.010*
RDW (%)	12.84 (1.19)	13.35 (1.59)	13.32 (1.08)	.000***	.001**	.255
Medication history, n (%)
Antihypertensive therapy	50 (49)	117 (57)	18 (35)	.184	.138	.077
Antiglycemic therapy	12 (11)	45 (22)	8 (16)	.573	.867	.367
Antiplatelet therapy	36 (35)	94 (46)	26 (51)	.095	.143	.389
Statin therapy	5 (5)	16 (8)	6 (12)	.713	.133	.279
Thrombolysis treatment	29 (28)	92 (45)		.001**
Stroke scale
ABCD^2 scores median (IQR)	5 (4–6)	6 (4–7)	6 (5–7)	.001**	.000***	.253
NIHSS scores median (IQR)	3 (3–5)	6 (3–7)	6 (4–8)	.000***	.000***	.665
MRS scores median (IQR)	0	1 (0–1)	1 (0–2)	.000***	.000***	.614
Aetiology classification, n (%)
LAA	20 (19)	45 (22)		.404
SVO	28 (27)	89 (43)		.038*
CE	16 (16)	35 (17)		.459
SUE	39 (38)	37 (18)		.003**
Mortality, n (%)
Number of deaths after 30 days	0 (0)	2 (0.009)	1 (0.019)			.489

BMI: body mass index, defined as weight in kilograms divided by the square of height in metres; SBP: systolic blood pressure; DBP: diastolic blood pressure; WBC: white blood cells; N/L:Neutrophilic/lymphocytes; HGB: haemoglobin; RBC: red blood cell; RDW: red blood cell distribution width; PLT: blood platelet; ALT: alanine transaminase; TBIL: total bilirubin；CR: creatinine; CRP: c reactive protein; FIB: fibrinogen; ALB: albumin; UA: uric acid; HCY: Homocysteine; TG: triglycerid; TC: total cholesterol; LDL: low-density lipoprotein cholesterol; HDL: high-density lipoprotein cholesterol; FBG: fasting blood-glucose; ABCD²:Age, Blood Pressure, Clinical Features, Duration, and Diabetes; National Institutes of Health Stroke Scale: NIHSS; Modified Rankin Scale: MRS; Values are expressed as Mean ± SD, median (IQR). p¹: TIA vs. IS patients; p²: TIA patients vs. HS patients; p³: IS patients vs. HS patients. The differences were considered significant if p-value < .05. ***p-Value < .001, **p-value < .01, *p-value < .05.

Figure 2. (A–F) Correlation analysis about oxidative stress and inflammatory markers.

Table 2. Risk factors for stroke using multiple logistic regression.

	OR	95% CI	p-Value
Risk factors for IS
RDW	2.523	1.464–3.345	.002**
CRP	1.098	1.035–1.164	.007*
ALB	0.844	0.766–0.930	.001**
HCY	1.062	1.010–1.116	.019*
GLU	1.240	1.062–1.449	.007*
Risk factors for HS
RDW	1.511	1.101–2.074	.011*
TB	1.079	1.006–1.156	.032*

The differences were considered significant if p-value < .05. ***p-Value <.001, **p-value < .01, *p-value < .05.

Figure 3. (A–D) Distribution characteristics of RDW value in TIA and stroke group, age, stroke onset time and stroke aetiology.

Table 3. Distribution characteristics of RDW value in age, stroke onset time and stroke aetiology.

	TIA (n = 103)	IS (n = 206)	HS (n = 51)	p^1-Value	p^2-Value	p^3-Value
Age distribution of RDW
≥30 to <45 years, median (SD)	12.71 (0.64)	13.16 (1.77)	12.76 (0.79)	.863	.819	.975
≥45 to <60 years, median (SD)	13.07 (1.54)	13.21 (1.31)	13.09 (0.83)	.384	.824	.453
≥60 to ≤80 years, median (SD)	13.26 (0.83)	13.55 (1.79)	13.90 (1.22)	.184	.023*	.064
Time of stroke after TIA
1 day, median (SD)		14.11 (1.43)	14.29 (1.63)			.749
2 days, median (SD)		13.57 (1.39)	13.66 (1.08)			.390
3–7 days, median (SD)		13.00 (0.89)	13.03 (0.64)			.423
Stroke aetiology
LAA (SD)	12.53 (0.87)	13.45 (1.73)		.017*
SVO (SD)	13.20 (1.43)	13.13 (0.95)		.682
CE (SD)	12.59 (0.68)	12.90 (0.89)		.259
SUE (SD)	12.77 (1.26)	13.57 (1.99)		.002*

p¹: TIA vs. IS patients; p²: TIA patients vs. HS patients; p³: IS patients vs. HS patients. The differences were considered significant if p-value < .05. ***p-Value < .001, **p-value < .01, *p-value < .05.

Figure 4. The ROC curve analysis of admission RDW for predicting the stroke after TIA.

Figure 5. The ROC curve analysis of admission RDW for predicting the stroke aetiology.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.