Table 1 Baseline characteristics of participants with metabolic syndrome. Continuous variables that follow a normal distribution are represented as mean ± standard deviation, other continuous variables are shown as median and quartiles, while the t-test or wilcoxon rank-sum test was applied to detect significant difference between surviving group and deceased group. Categorical variables are displayed as count and proportion with the chi-square test employed to determine the difference between two groups. Abbreviations: BMI, body mass index; TC, total cholesterol; TG, triglyceride; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; FBG, fasting blood glucose; FINS, fasting insulin; SCr, serum creatinine; eGFR, estimated glomerular filtration rate; UACR, urine albumin to creatinine ratio; TyG, triglyceride-glucose; HOMA-IR, homeostasis model assessment - insulin resistance; HOMA-IS, homeostasis model assessment - insulin sensitivity; HOMA-β, homeostasis model assessment of beta-cell function; QUICKI, quantitative insulin sensitivity check index; IGR, insulin glucose ratio; e-IS, estimated insulin sensitivity; Bennett ISI, Bennett’s insulin sensitivity index.

Age, years, mean (SD)

51.81 ± 15.92

69.36 ± 11.75

<0.001

Gender

<0.001

Male

2141(41.4%)

729(48.67%)

Female

3023(58.6%)

769(51.33%)

Race/Ethnicity, n (%)

<0.001

Mexican American

1106(21.4%)

220(14.69%)

Other Hispanic

482(9.3%)

71(4.73%)

Non-Hispanic White

2338(45.2%)

923(61.62%)

Non-Hispanic Black

980(18.9%)

246(16.42%)

Other races

258(4.9%)

38(2.54%)

Education level, n (%)

<0.001

Below high school

1507(29.2%)

602(40.19%)

High school graduate or GED

1065(20.6%)

382(25.50%)

Some college or above

2592(50.2%)

514(34.31%)

Poverty-to-income ratio

<0.001

≤1.5

1887(36.5%)

622(41.52%)

1.5–4.0

2050(39.7%)

658(43.93%)

>4.0

1227(23.8%)

514(34.31%)

Marital status, n (%)

<0.001

Married or living with a partner

3346(64.8%)

820(54.74%)

Never married

687(13.3%)

127(8.48%)

Widowed, divorced, or separated

1131(21.9%)

551(36.78%)

Alcohol use, n (%)

<0.001

Never drinking

2259(43.7%)

850(56.74%)

1–5 drinks/month

2580(50.0%)

599(39.99%)

5–10 drinks/month

249(4.8%)

39(2.60%)

>10 drinks/month

76(1.5%)

10(0.67%)

Smoking, n (%)

<0.001

Never

2791(54.0%)

624(41.66%)

Former

1381(26.8%)

619(41.32%)

Current

992(19.2%)

255(17.02%)

Waist circumference, cm

110.78 ± 13.47

110.54 ± 12.80

0.529

BMI, kg/m²

33.62 ± 6.41

31.86 ± 5.67

<0.001

Comorbidities

Congestive heart failure, n (%)

162(3.13%)

202(13.48%)

<0.001

Coronary artery disease, n (%)

394(7.6%)

378(25.23%)

<0.001

Hypertension, n (%)

3470(67.2%)

1276(85.18%)

<0.001

Stroke, n (%)

186(3.6%)

175(11.68%)

<0.001

Chronic kidney disease, n (%)

495(9.6%)

745(49.73%)

<0.001

Diabetes, n (%)

1311(25.4%)

633(42.26%)

<0.001

Cancer, n (%)

495(9.6%)

291(19.43%)

<0.001

Antidiabetic medicines, n (%)

965(18.7%)

481(32.11%)

<0.001

Baseline characteristics of laboratory blood test

TC, mmol/L

5.19 ± 1.17

5.13 ± 1.18

0.080

TG, mmol/L

2.06 ± 1.60

2.07 ± 1.48

0.829

LDL-C, mmol/L

3.39 ± 1.17

3.55 ± 2.23

0.777

HDL-C, mmol/L

1.19 ± 0.34

1.25 ± 0.40

<0.001

HbA1c (%)

5.6(5.30,5.90)

5.9(5.50,6.70)

<0.001

FBG, mmol/L

5.77(5.38,6.22)

6.13(5.47,7.38)

<0.001

FINS, pmol/L

94.62(64.92,140.16)

84.57(55.07,138.75)

<0.001

SCr, umol/L

75.14 ± 27.06

93.35 ± 55.42)

<0.001

eGFR, mL/min/1.73 m2

87.24 ± 25.27

79.59 ± 38.37

<0.001

UACR (mg/g)

7.50(4.83,14.90)

15.89(7.14 ± 50.00)

<0.001

Insulin resistance indices

TyG

9.09 ± 0.63

9.20 ± 0.66

<0.001

HOMA-IR

3.87(2.36,6.08)

3.20(1.53,6.27)

<0.001

HOMA-IS

0.24(0.15,0.40)

0.31(0.16,0.65)

<0.001

HOMA-β

123.67(75.28,198.83)

73.76(23.09,130.34)

<0.001

QUICKI

0.32(0.30,0.36)

0.32(0.29,0.38)

0.052

IGR, U/mol

2.47(1.55,3.76)

1.66(0.73,2.87)

<0.001

e-IS

4.28 ± 1.52

4.16 ± 1.49

0.009

Bennett ISI

1.09(0.91,1.32)

1.10(0.84,1.49)

<0.001