Table 1 Baseline characteristics of the young adult population according to metabolic syndrome burden scores during the four years

Participants, n

1,376,540

1,064,241

160,944

76,096

45,560

29,699

< 0.0001

Men

984,497(71.52)

697,200(65.51)

145,149(90.19)

70,908(93.18)

42,936(94.24)

28,304(95.3)

Women

392,043(28.48)

367,041(34.49)

15,795(9.81)

5188(6.82)

2624(5.76)

1395(4.7)

Age, years

32.41 ± 4.11

32.01 ± 4.16

33.47 ± 3.71

33.87 ± 3.55

34.14 ± 3.46

34.48 ± 3.34

< 0.0001

20–29

352,088(25.58)

311,721(29.29)

24,434(15.18)

8967(11.78)

4600(10.1)

2366(7.97)

30–39

1,024,452(74.42)

752,520(70.71)

136,510(84.82)

67,129(88.22)

40,960(89.9)

27,333(92.03)

Current smokers

512,392(37.22)

349,299(32.82)

79,982(49.7)

40,418(53.11)

25,354(55.65)

17,339(58.38)

< 0.0001

Heavy alcohol drinker

126,604(9.2)

81,771(7.68)

21,439(13.32)

11,325(14.88)

7188(15.78)

4881(16.43)

< 0.0001

Regular exercise (yes)

242,926(17.65)

185,673(17.45)

29,865(18.56)

13,983(18.38)

8275(18.16)

5130(17.27)

< 0.0001

Low income (lower 25%)

377,051(27.39)

282,026(26.5)

47,400(29.45)

23,456(30.82)

14,460(31.74)

9709(32.69)

< 0.0001

Body mass index, kg/m²

23.52 ± 3.6

22.53 ± 2.97

25.73 ± 3.16

27.25 ± 3.28

28.47 ± 3.4

29.81 ± 3.55

< 0.0001

Waist circumference, cm

73.68 ± 7.12

70,202(6.6)

52,771(32.79)

39,519(51.93)

30,594(67.15)

24,307(81.84)

< 0.0001

Systolic blood pressure, mmHg

118.91 ± 12.71

116.44 ± 11.69

124.91 ± 11.78

128.01 ± 11.99

130.47 ± 12.49

133.64 ± 13.33

< 0.0001

Diastolic blood pressure, mmHg

74.81 ± 9.14

73.18 ± 8.43

78.67 ± 8.65

80.87 ± 8.98

82.62 ± 9.55

84.99 ± 10.31

< 0.0001

Fasting plasma glucose, mmol/l

90.56 ± 10.25

89.06 ± 9.5

94.22 ± 10.66

96.02 ± 10.94

97.64 ± 11.25

99.32 ± 11.65

< 0.0001

Total cholesterol, mg/dL

189.04 ± 33.86

184.9 ± 31.98

199.79 ± 35.3

205 ± 36.16

207.94 ± 36.9

209.33 ± 38.23

< 0.0001

Triglycerides, mg/dL^*

104.68(104.57-104.78)

89.7(89.61–89.79)

154.91(154.51-155.31)

186.4(185.73-187.08)

211.72(210.76-212.68)

244.9(243.57-246.23)

< 0.0001

HDL cholesterol, mg/dL

56.21 ± 18.46

58.79 ± 18.42

49.41 ± 16.27

46.57 ± 15.02

44.72 ± 13.86

42.81 ± 14.49

< 0.0001

LDL cholesterol, mg/dL

108.73 ± 32.32

106.01 ± 30.47

116.91 ± 34.94

119.16 ± 36.51

119.74 ± 38.75

117.96 ± 40.32

< 0.0001

Hypertension (%)

99,625(7.24)

37,842(3.56)

20,293(12.61)

15,324(20.14)

13,103(28.76)

13,063(43.98)

< 0.0001

Dyslipidemia (%)

116,293(8.45)

58,991(5.54)

22,972(14.27)

14,568(19.14)

10,641(23.36)

9121(30.71)

< 0.0001

Metabolic syndrome components

Elevated fasting glucose (%)

239,081(17.37)

125,235(11.77)

49,620(30.83)

29,097(38.24)

20,168(44.27)

14,961(50.38)

< 0.0001

Elevated triglycerides (%)

377,870(27.45)

171,008(16.07)

88,799(55.17)

53,764(70.65)

37,029(81.28)

27,270(91.82)

< 0.0001

Reduced HDL cholesterol (%)

187,631(13.63)

84,550(7.94)

39,935(24.81)

26,348(34.62)

19,848(43.56)

16,950(57.07)

< 0.0001

Elevated blood pressure (%)

392,067(28.48)

209,796(19.71)

78,815(48.97)

46,818(61.52)

32,173(70.62)

24,465(82.38)

< 0.0001

Abdominal obesity (%)

217,393(15.79)

70,202(6.6)

52,771(32.79)

39,519(51.93)

30,594(67.15)

24,307(81.84)

< 0.0001

Follow-up duration, median (years)

5.18 (4.14–5.51)

5.18 (4.13–5.51)

5.18 (4.21–5.5)

5.16 (4.18–5.48)

5.15 (4.12–5.47)

5.12 (3.9–5.44)

< 0.0001