Table 1 Comparisons of sociodemographic factors, lifestyle behaviors, clinical and biochemical markers, and comorbidities according to smoking status and metabolic syndrome

Sociodemographic factors, n (%)

 Gender

 < 0.001

 < 0.001

 Men

27,898 (34.84)

11,876 (20.24)

16,022 (74.87)

19,885 (30.93)

8013 (50.80)

 Women

52,174 (65.16)

46,797 (79.76)

5377 (25.13)

44,414 (69.07)

7760 (49.20)

 Age, years, mean ± SD

49.65 ± 10.65

49.84 ± 10.69

49.14 ± 10.51

 < 0.001

48.63 ± 10.58

53.81 ± 9.87

 < 0.001

Education level (year)

 < 0.001

 < 0.001

 ≤ 6

4132 (5.16)

3416 (5.82)

716 (3.35)

2724 (4.24)

1408 (8.93)

 7–12

29,548 (36.9)

21,047 (35.87)

8501 (39.73)

22,829 (35.5)

6719 (42.60)

 ≥ 13

46,392 (57.94)

34,210 (58.31)

12,182 (56.93)

38,746 (60.26)

7646 (48.48)

Marriage status

 < 0.001

 < 0.001

 Unmarried

10,492 (13.10)

7688 (13.10)

2804 (13.10)

9102 (14.16)

1390 (8.81)

 Married

59,271 (74.02)

43,449 (74.05)

15,822 (73.94)

47,202 (73.41)

12,069 (76.52)

 Divorce or separation

6835 (8.54)

4488 (7.65)

2347 (10.97)

5440 (8.46)

1395 (8.84)

 Widowed

3474 (4.34)

3048 (5.19)

426 (1.99)

2555 (3.97)

919 (5.83)

Living alone

0.14

0.80

 No

73,558 (91.86)

53,951 (91.95)

19,607 (91.63)

59,060 (91.85)

14,498 (91.92)

 Yes

6514 (8.14)

4722 (8.05)

1792 (8.37)

5239 (8.15)

1275 (8.08)

Lifestyle behaviors, n (%)

 Alcohol drinking

 < 0.001

 < 0.001

 No

73,394 (91.66)

56,937 (97.04)

16,457 (76.91)

59,760 (92.94)

13,634 (86.44)

 Ever

2040 (2.55)

467 (0.8)

1573 (7.35)

1342 (2.09)

698 (4.43)

 Yes

4638 (5.79)

1269 (2.16)

3369 (15.74)

3197 (4.97)

1441 (9.14)

Leisure time physical activity

 < 0.001

 < 0.001

 No

48,101 (60.07)

34,821 (59.35)

13,280 (62.06)

38,836 (60.40)

9265 (58.74)

 Yes

31,971 (39.93)

23,852 (40.65)

8119 (37.94)

25,463 (39.60)

6508 (41.26)

Clinical and biochemical markers, mean ± SD

 Waistline, cm

83.17 ± 10.17

81.84 ± 9.81

86.83 ± 10.25

 < 0.001

80.9 ± 9.1

92.43 ± 8.97

 < 0.001

 BMI, kg/m²

24.22 ± 3.77

23.87 ± 3.69

25.18 ± 3.84

 < 0.001

23.43 ± 3.34

27.41 ± 3.75

 < 0.001

 SBP, mmHg

119.41 ± 17.87

118.29 ± 17.85

122.49 ± 17.58

 < 0.001

115.97 ± 16.37

133.44 ± 16.86

 < 0.001

 DBP, mmHg

73.37 ± 11.03

72.28 ± 10.74

76.35 ± 11.25

 < 0.001

71.48 ± 10.22

81.08 ± 10.86

 < 0.001

 FPG, mg/dL

95.76 ± 20.48

94.74 ± 18.94

98.57 ± 23.98

 < 0.001

92.09 ± 13.43

110.73 ± 33.39

 < 0.001

 HbA1c, %

5.76 ± 0.8

5.74 ± 0.75

5.83 ± 0.91

 < 0.001

5.62 ± 0.56

6.35 ± 1.24

 < 0.001

 TG, mg/dL

116.22 ± 97.32

108.19 ± 80.32

138.25 ± 130.71

 < 0.001

95.78 ± 57.68

199.54 ± 160.84

 < 0.001

 TC, mg/dL

195.91 ± 35.95

196.71 ± 35.91

193.7 ± 35.97

0.024

195.1 ± 34.77

199.19 ± 40.25

 < 0.001

 HDL-C, mg/dL

54.61 ± 13.45

56.3 ± 13.36

50 ± 12.6

 < 0.001

57.07 ± 12.93

44.59 ± 10.59

 < 0.001

 LDL-C, mg/dL

121.11 ± 31.84

121.01 ± 31.74

121.37 ± 32.13

0.16

120.71 ± 31.08

122.73 ± 34.73

 < 0.001

 Albumin, g/dL

4.51 ± 0.23

4.5 ± 0.23

4.55 ± 0.24

 < 0.001

4.51 ± 0.23

4.55 ± 0.23

 < 0.001

 SCr, mg/dL

0.72 ± 0.31

0.67 ± 0.26

0.84 ± 0.4

 < 0.001

0.7 ± 0.26

0.8 ± 0.47

 < 0.001

 eGFR, mL/min/1.73 m²

102.54 ± 14.74

103.62 ± 14.14

99.59 ± 15.92

 < 0.001

104.06 ± 13.92

96.37 ± 16.31

 < 0.001

Comorbidities, n (%)

Hypertension

 < 0.001

 < 0.001

 No

70,545 (88.1)

52,463 (89.42)

18,082 (84.5)

60,322 (93.81)

10,223 (64.81)

 Yes

9527 (11.9)

6210 (10.58)

3317 (15.5)

3977 (6.19)

5550 (35.19)

Hyperlipidemia

 < 0.001

 < 0.001

 No

74,253 (92.73)

54,808 (93.41)

19,445 (90.87)

62,075 (96.54)

12,178 (77.21)

 Yes

5819 (7.27)

3865 (6.59)

1954 (9.13)

2224 (3.46)

3595 (22.79)

Diabetes

 < 0.001

 < 0.001

 No

76,109 (95.05)

56,092 (95.60)

20,017 (93.54)

63,044 (98.05)

13,065 (82.83)

 Yes

3963 (4.95)

2581 (4.40)

1382 (6.46)

1255 (1.95)

2708 (17.17)

Stroke

 < 0.001

 < 0.001

 No

79,588 (99.4)

58,408 (99.55)

21,180 (98.98)

64,059 (99.63)

15,529 (98.45)

 Yes

484 (0.6)

265 (0.45)

219 (1.02)

240 (0.37)

244 (1.55)

Valvular heart disease

 < 0.001

 < 0.001

 No

76,666 (95.75)

56,015 (95.47)

20,651 (96.50)

61,404 (95.50)

15,262 (96.76)

 Yes

3406 (4.25)

2658 (4.53)

748 (3.50)

2895 (4.50)

511 (3.24)

Coronary artery disease

 < 0.001

 < 0.001

 No

79,169 (98.87)

58,197 (99.19)

20,972 (98.00)

63,863 (99.32)

15,306 (97.04)

 Yes

903 (1.13)

476 (0.81)

427 (2.00)

436 (0.68)

467 (2.96)

Arrhythmia

0.001

 < 0.001

 No

76,500 (95.54)

56,141 (95.68)

20,359 (95.14)

61,646 (95.87)

14,854 (94.17)

 Yes

3572 (4.46)

2532 (4.32)

1040 (4.86)

2653 (4.13)

919 (5.83)

Cardiomyopathy

 < 0.001

 < 0.001

 No

79,465 (99.24)

58,299 (99.36)

21,166 (98.91)

63,984 (99.51)

15,481 (98.15)

 Yes

607 (0.76)

374 (0.64)

233 (1.09)

315 (0.49)

292 (1.85)

Congenital heart disease

0.80

0.06

 No

79,919 (99.81)

58,559 (99.81)

21,360 (99.82)

64,186 (99.82)

15,733 (99.75)

 Yes

153 (0.19)

114 (0.19)

39 (0.18)

113 (0.18)

40 (0.25)

Other heart disease

0.39

0.24

 No

79,944 (99.84)

58,584 (99.85)

21,360 (99.82)

64,202 (99.85)

15,742 (99.80)

 Yes

128 (0.16)

89 (0.15)

39 (0.18)

97 (0.15)

31 (0.20)