Table 1 Summary and baseline characteristics of included studies

Jousilahti et al. (2000)

Finland

7176 (48.5)

25–64

13

T national hospital discharge register (ICD-8 & ICD-9)

M: 10.8, 16.4, 24.6, 64.2

W: 7, 9.9, 13.6, 33.9

Age, study year, smoking, TC, SBP, DBP, BMI

Kim et al. (2005)

Korea

108 464 (100)

35–59

10

The Korea Medical Insurance Corporation (KMIC)

< 35, (35–69) and ≥ 70

Age, BMI, blood pressure, FBG, TC, smoking, and alcohol consumption

Korantzopoulos et al. (2009)

Greece

175 (53.2)

77.6 *

5

History, physical examination, imaging study (non-contrast brain CT scan), full cardiac evaluation and carotid Doppler ultrasound

< 16, 16–21, 21–27, > 27

Sex, age, smoking habits, BMI, HTN, DM, metabolic syndrome and serum levels of lipid parameters, glucose, insulin, creatinine, uric acid, AST, ALT, ALP, and total bilirubin

Shimizu et al. (2010)

Japan

3471 (36.7)

40–69

18.1 ^a

Physicians examination, CT/MRI, clinical criteria

M: < 15, (15–24), (24–45), > 45

W: < 8, (9–11), (11–16),

> 16

Age and community, BMI, smoking, alcohol intake, TC, serum triglycerides, serum albumin, AST, ALT, SBP, antihypertensive medication use, and DM

Weikert et al. (2013)

Germany

940 (38.9)

35–65

8.2 ^b

Medical records and death certificates, brain imaging (MRI or CT), and ICD-10

GGT: M: (3.3–15.4), (16.5–25.3), (26.4–42.9), (44.0-2401)

W: (1.1–7.7), (8.8–12.1), (13.2–19.8), (20.9–485)

ALT: M: (5.5–17.6), (18.7–24.2), (25.3–35.2), (36.3–265)

W: (2.2–12.1), (13.2–15.4), (16.5–20.9), (22.0-209)

Age, sex, BMI, waist circumference, smoking, alcohol intake, education, sports, HTN, DM, total and HDL-cholesterol, and hsCRP

Shimizu et al. (2013)

Japan

4098 (38.1)

40–69

16

National insurance claims, physicians, death certificates, and cardiovascular risk surveys

M: 63, (63–72), (73–83), (84–96),96

W: 59, (59–70), (71–82), (83–98), 98

Age and community, BMI, smoking, alcohol consumption, TC, serum albumin, AST, ALT, g-GTP, GFR, SBP, antihypertensive medication use, DM, thyroid disease, and for women menopausal status

Ryu et al. (2014)

South Korea

558 (51.6%)

20–82

1

MRI brain, assessment of FLIAR and T1-weighted sequences

<53, (54–63), (64–76), ≥ 77

Age, sex, HTN, DM, smoking, CHD, serum phosphate, calcium, ALT, LDL-cholesterol, C-reactive protein (log-transformed), and GFR

Tan et al. (2016)

China

760

(57.0)

18–39

5.5

WHO criteria and CT or MRI scan

AST: (5–18), (19–22), (23–29), (30–531)

GGT: (7–16), (17–25), (26–42), (43–898)

Age, gender, HTN, DM, dyslipidemia, atrial fibrillation, history of stroke, alcohol consumption and smoking, NIHSS score, and SBP

Dar et al. (2016)

Pakistan

288 (73.8)

40–80

0.5

CT scan of brain was performed, and diagnosis was confirmed

> 27 IU/L

N/A

Liang et al. (2017)

China

312

(64.2)

65.59 *

2.5

According to the WHO criteria

N/A

Age, sex, SBP, DBP, cigarette smoking

Uehara et al. (2018)

Japan

55 (67)

69.3 *

7.5

DWI to evaluate whether acute ischemic lesions were present

ALP: ≥292 U/L

N/A

Alexander et al. (2018)

United States of America

13,607 (45%)

64.7 *

4

Medical records and death certificates

AST: M: (15.4, 18.5, 21.3, 25.5), W: AST (14.1, 16.4, 19.4, 23.1)

ALT: M: (12.1, 15.1, 18.9, 24.2), W: (9.3, 12.5, 14.9, 19.2)

GGT: M: (17.0 21.6, 28.1, 41.8), W: (12.8, 16.9, 22.6, 31.2)

Age, race, and Framingham stroke risk factors

Yang et al. (2018)

South Korea

236,889 (51.9%)

20–84

10

General health clinical examination and ICD-10, code: I63

(10–17), (13–25), (18–39), (32–90)

Age, sex, alcohol consumption, BMI, SBP, FBG, TC, hemoglobin, AST, ALT, DM, previous stroke, HTN, atrial fibrillation, ischemic heart disease, heart failure, liver disease, cancer, CKD, osteoporotic fracture, smoking status, antiepileptic drug or rifampicin use, pregnancy within 1 year, and social economic status

Yang et al. (2020)

South Korea

525 (59.6)

68.93 *

15

The National Institutes of Health Stroke Scale score, and TOAST classification

M: ≤20, (21–29), (30–53), and ≥ 54

W: ≤14, (15–21),

(22–34), and ≥ 35

Sex, age, BMI, SBP, FBG, TC, AST, ALT, previous stroke, HTN, DM, hyperlipidemia, liver disease, and smoking

Ruban et al. (2020)

United States of America

5,504 (43.7)

45–46

24.2 ^a

Stroke hospitalizations records, ICD-9 or ICD-10 and physician review

AST: M: <12, 12–15, 16–21, ≥ 25; W: <16,

16–18, 19–21, ≥ 22

ALT: M: <18, 18–21, 21–25, ≥ 22; W: <12, 10–12, 13–16, ≥ 17

GGT: M: <18, 18–24, 25–37, ≥ 38; W: <13, 13–17, 18–28, ≥ 29

Age, sex, race-center; BMI, smoking status, drinking status, education level, SBP, HTN medication, DM, HDL, TC, lipids medication, and CHD

Lee et al. (2021)

Korea

118,375 (56.5%)

57.8 *

5

Medical records and ICD, code: I63

<16, (≥ 16, < 24)

(≥ 24, < 41), ≥ 41

Age, gender, BMI, systolic BP, FBG, TC, eGFR, smoking amount (pack-year), alcohol intake and physical activity

Li et al. (2022)

China

8,506 (68.03)

62.33 *

4

WHO criteria, and neuroimaging (MRI or brain CT)

M: <19, 19–27, 27–43,

≥ 43

W: <14, 14–20, 20–29, ≥ 29)

Age and sex, BMI, smoking, alcohol consumption, medical histories, SBP, DBP, NIHSS score at admission, pre-stroke mRS score, TOAST types (including large-artery atherosclerosis, cardioembolic, small-vessel occlusion, other determined etiology, and undetermined cause), medications during hospitalization (including antiplatelet therapy, anticoagulation treatment, antihypertensive treatment, lipid-lowering drugs), and laboratory tests (FBG, TC, triglycerides, ALT, AST levels)

Kim et al. (2023)

Korea

1,968 (63.6)

48–87

8.9 ^a

Hospitalization records with stroke code ICD-10, code: I63

M: ≤20, 21–30, 31–52, ≥ 54

W: ≤11, 12–15, 16–22, ≥ 23

Age, sex, residential area, health insurance type, insurance premium, BMI, fasting serum glucose, TC, AST, ALT, cigarette smoking, alcohol consumption, physical activity, family history of stroke, Charlson comorbidity index, and aspirin use, presence of atrial fibrillation/flutter

Liu et al. (2023)

China

11,408 (43.2)

M: 65.2 * W:58.9 *

7.3 ^c

Hospital records, and medical insurance documents

M: < 69, 69–84, 84–100, > 100

W: < 71, 71–87, 87–105, > 105

Age, admission batch, BMI, smoking status, drinking status, physical activity, HTN, hyperlipidemia, DM, aspirin usage, anticoagulants usage, menopausal status (women only), family history of CVD, and eGFR, WBC

Arafa et al. (2023)

Japan

3,379 (45.7)

< 50, 50–59,

60–69, or ≥ 70 **

16.7 ^a

The US National Survey of Stroke criteria based on CT or MRI images

ALT: ≤ 30, 31–50, > 50

AST: ≤ 30, 31–50, > 50

GGT: ≤ 50, 51–100, > 100

Age, BMI, smoking, alcohol consumption, HTN, DM, HDL-C, TC, CKD, and cardiac murmur