Lipid profiles and ischemic stroke risk: variations by sex within racial/ethnic groups

Figures & data

Table 1 Characteristics of patients with acute stroke on admission, by sex within racial/ethnic groups

Characteristic	Race/ethnicity
	White (n=2,156)	African American (n=605)	South Asian (n=273)	Hispanic (n=256)
Female, %a	55.0	59.7	40.7	46.9
Mean age in years (± SD)
Male	70.3 (14.2)	64.3 (13.2)	64.5 (13.8)	62.8 (14.7)
Female	75.3 (14.2)	64.9 (15.4)	66.0 (15.6)	65.1 (17.4)
P-valuea	<0.0001	NS	NS	NS
Clinical measurements on admission
Mean TC in mg/dL (± SD)b
Male	165.2 (42.9)	166.6 (48.3)	172.8 (44.2)	171.2 (54.3)
Female	176.9 (45.2)	184.7 (45.2)	171.5 (46.1)	183.1 (45.0)
P-valueb,c	<0.0001	<0.0001	NS	NS
Mean HDL in mg/dL (± SD)b
Male	39.6 (11.3)	40.7 (14.4)	39.4 (11.6)	38.3 (11.5)
Female	46.6 (14.6)	48.1 (15.0)	44.5 (11.8)	43.7 (10.4)
P-valueb,c	<0.0001	<0.0001	0.0010	0.0006
Mean LDL in mg/dL (± SD)b
Male	101.8 (37.1)	103.1 (38.3)	108.4 (37.4)	110.4 (44.3)
Female	106.1 (39.6)	115.9 (38.5)	101.5 (39.1)	112.1 (36.1)
P-valueb,c	0.0177	0.0006	NS	NS
Mean systolic blood pressure in mmHg (± SD)
Male	150.1 (28.3)	153.5 (32.2)	153.8 (31.9)	149.6 (27.6)
Female	154.8 (32.1)	154.0 (32.1)	161.6 (33.3)	154.1 (28.8)
P-valuec	0.0006	NS	NS	NS
Mean diastolic blood pressure in mmHg (± SD)b
Male	83.1 (17.8)	87.3 (21.2)	87.1 (18.1)	83.3 (16.3)
Female	82.4 (19.4)	85.4 (19.3)	88.0 (25.2)	82.5 (18.3)
Mean body mass index in kg/m^2 (± SD)b
Male	27.7 (5.5)	28.0 (6.4)	25.4 (4.3)	27.9 (4.3)
Female	27.1 (6.3)	29.8 (7.5)	26.5 (5.8)	28.8 (7.0)
P-valuec	0.0059	0.0029	NS	NS
Geometric mean fasting blood glucose in mg/dL (95% CI)b
Male	125.0 (122.3–127.8)	126.9 (120.7–133.5)	126.5 (119.3–134.1)	128.5 (120.4–137.2)
Female	119.7 (117.4–121.9)	126.5 (121.3–131.8)	138.2 (127.6–149.8)	128.5 (119.3–138.4)
Geometric mean HbA1c in % (95% CI)b
Male	6.3 (6.2–6.4)	6.5 (6.3–6.7)	6.8 (6.5–7.0)	6.4 (6.2–6.7)
Female	6.2 (6.1–6.3)	6.5 (6.4–6.7)	6.9 (6.6–7.2)	6.4 (6.1–6.6)
Geometric mean triglycerides in mg/dL (95% CI)b
Male	107.6 (103.9–111.3)	92.9 (86.1–100.3)	115.9 (106.3–126.4)	107.9 (94.5–123.1)
Female	107.4 (104.2–110.6)	91.6 (86.5–97.0)	115.6 (104.0–128.4)	117.2 (106.3–129.2)

Notes:

a χ² test P<0.0001.

b Statistical test did not include missing values (~12%–17% for TC, LDL/HDL and 35% for HbA_1c); also P-values for variables that were not statistically significantly different by sex are not shown.

c Analysis of variance for comparing means.

Abbreviations: CI, confidence interval; HbA_1c, glycated hemoglobin; HDL, high-density lipoprotein; LDL, low-density lipoprotein; NS, not significant at P=0.05 level; SD, standard deviation; TC, total cholesterol.

Table 2 Percentage severity of hypercholesterolemia and lipid profiles for acute stroke patients, by sex within racial/ethnic groups

	Race/ethnicity (N=3,290)				P-valuea
	White	African American	South Asian	Hispanic
LDL-c level on admission ≥100 mg/dL, %b
Yes (n=1,346)	47.9	57.9	52.8	56.2	0.0003
Male	42.6	36.2	63.6	48.7
Female	57.4	63.8	36.4	51.3
No (n=1,299)	52.1	42.1	47.2	43.8
P-valuec	0.0462	0.0111	NS	NS
Cholesterol reducers on admission, %d
Yes (n=1,394)	45.0	37.3	37.5	38.3	0.0007
Male	48.3	43.1	61.8	53.1
Female	51.7	56.9	38.2	46.9
No (n=1,890)	55.0	62.8	62.5	61.7
P-valuec	0.0058	NS	NS	NS
Cholesterol reducers at discharge, %
Statin (n=1,852)e	55.0	60.5	65.6	59.2	0.0027
Male	47.4	40.2	64.5	56.7
Female	52.6	59.8	35.5	43.3
P-value	0.0076	NS	0.0325	NS
Other medications	1.2	0.8	0.4	1.2
Contraindicated	5.4	3.8	4.0	7.0
None prescribed	37.3	34.1	31.3	28.6

Notes:

a χ² test for differences between racial/ethnic groups

b 19.6% data missing

c χ² test differences between the sexes within a racial/ethnic group

d less than 0.2% (n=6) data missing

e about 6% data missing.

Abbreviations: LDL-c, low-density lipoprotein cholesterol; NS, not significant at P<0.05 level.

Table 3 Proportion of prescription medication use and the prevalence of most common stroke risk factors prior to admission, by sex within racial/ethnic groups

	Race/ethnicity
	White (n=2,156)	African American (n=605)	South Asian (n=273)	Hispanic (n=256)
History of prescription medication use
Antihypertensive medications, %
Male	42.7	40.7	58.8	54.1
Female	57.3	59.3	41.2	45.9
P-valuea	0.0003	NS	NS	NS
Cholesterol-reducing medications, %
Male	48.3	43.1	61.8	53.1
Female	51.7	56.9	38.2	46.9
P-valuea	0.0060	NS	NS	NS
Antiplatelet medications, %b
Male	45.1	38.8	63.4	57.6
Female	54.9	61.2	36.6	42.4
Anticoagulant medications, %
Male	44.9	41.0	63.5	41.7
Female	55.1	59.0	36.5	58.3
P-valuea	NS	NS	NS	0.0216
Diabetic medications, %
Male	47.2	39.9	61.1	54.3
Female	52.8	60.1	38.9	45.7
Prevalence of most common stroke risk factors
Hypertension, %
Male	43.8	40.5	58.3	53.6
Female	56.2	59.5	41.7	46.4
P-valuea	0.0362	NS	NS	NS
Diabetes mellitus, %
Male	48.7	41.2	57.3	50.6
Female	51.4	58.8	42.7	49.4
P-valuea	0.0287	NS	NS	NS
Cardiac disease, %c
Male	47.0	43.8	68.7	59.7
Female	53.0	56.2	31.3	40.3
Dyslipidemia, %
Male	48.0	38.2	65.0	50.0
Female	52.0	61.8	35.0	50.0
P-valuea	0.0374	NS	NS	NS
Smoking history, %
Male	58.0	55.9	92.0	76.2
Female	42.0	44.1	8.0	23.8
P-valuea	<0.0001	0.0009	0.0005	0.0271
Previous stroke/TIAd
Male	47.5	39.0	61.2	50.7
Female	52.5	61.0	38.2	49.3
Any combinatione
Male	41.9	41.6	56.0	54.3
Female	58.1	58.4	44.0	45.7
P-valuea	0.0045	NS	NS	NS

Notes:

a χ² test for differences between racial/ethnic groups

b if P-values for statistical test were entirely not statistically significantly different by sex within racial/ethnic groups they were omitted from the table

c cardiac disease includes atrial fibrillation, prost heart valve, coronary artery disease/prior myocardial infarction, carotid stenosis, peripheral vascular diseases, and heart failure

d TIA duration <24 hours

e any combination of these risk factors.

Abbreviations: NS, not significant at P<0.05 level; prost, prosthetic; TIA, transient ischemic attack.

Table 4 Percentages of clinical diagnosis related to acute stroke, by sex within racial/ethnic groupsa

Diagnosis	Race/ethnicityb
	White (n=2,156)	African American (n=605)	South Asian (n=273)	Hispanic (n=256)
Ischemic stroke (n=1,541)c,d
Male	44.0	40.4	58.8	52.4
Female	56.0	59.6	41.2	47.6
Large artery atherosclerosis (n=360)
Male	42.3	48.3	44.4	56.3
Female	57.7	51.7	55.6	43.7
Small artery occlusions (n=354)
Male	47.1	31.8	52.5	44.0
Female	52.9	68.2	47.5	56.0
Cardioembolism (n=261)
Male	43.5	61.8	81.8	50.0
Female	56.5	38.2	18.2	50.0
Stroke of other determined and undetermined causes (n=547)
Male	42.8	36.3	68.8	55.2
Female	57.2	65.7	31.3	44.8
TIAe (n=1,179)
Male	44.5	35.8	61.5	51.1
Female	55.5	64.2	38.5	48.9
Subarachnoid hemorrhage (n=129)
Male	36.6	44.0	50.0	57.1
Female	63.4	56.0	50.0	42.9
Intracerebral hemorrhage (n=380)
Male	52.2	54.2	58.3	55.9
Female	47.8	45.8	41.7	44.1
Stroke not otherwise specified (n=23)
Male	42.9	50.0	100.0	100.0
Female	57.1	50.0	0.0	0.0
No stroke-related diagnosis (n=21)
Male	75.0	0.0	50.0	75.0
Female	25.0	100.0	50.0	25.0

Notes:

a Less than 0.5% of data was missing

b χ² test for differences between sexes within a racial/ethnic group

c ischemic stroke subtyping, based on classification scheme from the Trial of ORG 10172 in Acute Stroke Treatment (TOAST)

d approximately 1.2% of the data of ischemic stroke patients lacked subtyping information

e TIA duration <24 hours.

Abbreviation: TIA, transient ischemic attack.

Table 5 Relative risk, stroke risk factors as predictors of ischemic stroke subtypes,a by sex within racial/ethnic groups

Variable	Relative risk (95% CI)
	White	African American	South Asian	Hispanic
Age (per 10 years)
Male	0.98 (0.87–1.11)	1.22 (1.05–1.41)	0.83 (0.58–1.17)	1.13 (0.86–1.49)
Female	1.20 (1.06–1.37)	0.98 (0.76–1.26)	1.27 (1.02–1.58)	1.20 (0.93–1.55)
Smoking (Yes =1, No =0)
Male	1.03 (0.73–1.46)	0.98 (0.51–1.88)	–b	–c
Female	1.82 (1.36–2.45)	1.01 (0.33–3.15)	–	–
HDL (per 10 mg/dL)
Male	0.91 (0.78–1.05)	0.75 (0.61–0.93)	0.62 (0.35–1.09)	1.09 (0.92–1.30)
Female	0.88 (0.80–0.96)	1.06 (0.95–1.18)	0.93 (0.74–1.18)	1.01 (0.73–1.40)
Triglycerides (per 10 mg/dL)
Male	0.99 (0.97–1.01)	0.94 (0.88–1.00)	0.98 (0.93–1.04)	1.01 (0.97–1.05)
Female	0.97 (0.95–1.00)	0.99 (0.94–1.05)	1.01 (0.99–1.02)	0.99 (0.93–1.04)

Notes:

a Ischemic stroke subtyping based on classification scheme from the Trial of ORG 10172 in Acute Stroke Treatment (TOAST)

b due to the absence of women smokers in a dataset for South Asians, no comparison was done

c regression equation did not converge when smoking was included in the variable, small sample size-smoking was not included in the analysis.

Abbreviations: CI, confidence interval; HDL, high-density lipoprotein.

Table S1 Category of clinical characteristic measures on admission, by sex within racial/ethnic groups, in percentages

	Sex
	Male				Female
	Race/ethnicity				Race/ethnicity
	White (n=971)	African American (n=361)	South Asian (n=111)	Hispanic (n=120)	White (n=1,185)	African American (n=244)	South Asian (n=162)	Hispanic (n=136)
TC, %
Desirable (TC <200 mg/dL)	67.4	66.4	68.5	57.4	61.4	57.3	68.5	57.5
Borderline high (TC 200–239 mg/dL)	10.8	14.3	13.0	11.8	14.5	19.1	10.8	19.2
High (TC >240 mg/dL)	5.1	5.0	6.8	7.3	6.8	9.4	7.2	9.2
Missing	16.7	14.3	11.7	23.5	17.4	14.1	13.5	14.2
LDL, %
Near/above optimal (LDL <129 mg/dL)	66.5	66.4	64.2	56.6	64.5	60.1	70.3	61.6
Borderline high (LDL 130–159 mg/dL)	11.1	13.5	16.7	13.2	11.0	13.3	9.9	14.2
High (LDL 160–189 mg/dL)	4.6	5.7	6.2	5.9	5.2	10.2	2.7	7.5
Very high (LDL ≥190 mg/dL)	2.0	1.6	1.8	2.2	2.4	2.5	4.5	2.5
Missing	15.8	12.7	11.1	22.1	16.9	13.9	12.6	14.2
HDL, %
Low (HDL <40 mg/dL)	46.1	43.9	54.3	44.9	27.9	24.1	30.6	34.2
Mid-range (40 mg/dl ≤ HDL <60 mg/dL)	32.5	34.8	30.9	27.2	40.5	46.3	46.0	45.8
High (HDL ≥60 mg/dL)	4.5	7.4	3.1	4.4	14.1	15.5	9.9	5.8
Missing	16.8	13.9	11.7	23.5	17.5	14.1	13.5	14.2
TG, %
Normal (TG <150 mg/dL)	62.9	71.7	61.7	58.1	63.7	73.4	55.9	63.3
Borderline high (TG 150–199 mg/dL)	12.5	9.8	14.2	8.8	12.2	8.3	19.8	9.2
High (TG 200–499 mg/dL)	7.4	4.5	12.4	8.8	6.3	4.4	9.9	12.5
Very high (TG ≥500 mg/dL)	0.4	0.4	0.6	0.7	0.3	0.0	0.9	0.8
Missing	16.8	13.5	11.1	23.5	17.5	13.9	13.5	14.2
Blood Pressure Classification, %a
Normal (≤120/80 mmHg)	42.5	31.2	34.6	38.2	43.8	37.1	36.0	42.5
Prehypertension (120–139/80–89 mmHg)	20.7	22.5	26.5	27.9	20.8	21.6	18.0	20.8
Stage 1 hypertension (140–159/90–99 mmHg)	19.0	20.5	14.8	14.0	15.0	16.3	18.0	11.7
Stage 2 hypertension (>160/100 mmHg)	11.4	18.9	19.8	10.3	13.0	14.4	18.0	16.7
Missing	6.4	7.0	4.3	9.6	7.4	10.5	9.9	8.3
Blood glucose classification, %b
FBG <126 mm/dLc	54.1	49.2	58.0	46.3	57.0	50.4	41.4	51.7
FBG ≥126 mm/dL	35.0	40.2	35.8	41.2	31.1	35.7	46.0	38.3
Missing	10.9	10.6	6.2	12.5	11.7	13.9	12.6	10.0
HbA1c classifications, %b
HbA1c <6.5%	44.0	39.3	38.3	39.0	44.8	37.1	29.7	42.5
HbA1c ≥6.5%	19.3	27.1	32.7	27.2	16.5	30.2	43.2	21.7
Missing	36.8	33.6	29.0	33.8	38.7	32.7	27.0	35.8
BMI, %c
Underweight (BMI ≤18.5 kg/m^2)	0.5	1.6	1.9	0.0	3.6	2.5	4.5	2.5
Normal (BMI <24.9 kg/m^2)	29.2	29.2	49.4	25.0	35.1	20.2	36.0	23.3
Overweight (25.0< BMI <29.9 kg/m^2)	36.1	32.8	29.6	41.9	27.1	28.8	24.3	33.3
Obese (BMI ≥30.0 kg/m^2)	24.1	25.8	14.8	22.8	22.1	33.8	19.8	30.8
Missing	10.1	9.8	4.3	10.3	12.1	14.7	15.3	10.0

Notes:

a Blood pressure level based on the seventh report of the Joint National Committee on Hypertension, (JNC7)

b classification based on the criteria for diagnosis of diabetes by the American Diabetes Association, 2010

c BMI based on the Centers for Disease Control and Prevention BMI guidelines for weight status.

Abbreviations: BMI, body mass index; FBG, fasting blood glucose; HbA_1c, glycated hemoglobin; HDL, high-density lipoprotein; LDL, low-density lipoprotein; TC, total cholesterol; TG, triglycerides.