Table 2 Baseline characteristics of study participants in CHNS 2004 and anthropometric measures in 2015 by gender (N = 4207)

Age (years, mean ± SD)

44.8 ± 11.2

45.3 ± 10.5

0.123

Ethnicity (N, %)

0.876

 Han Chinese

1687 (86.3)

1947 (86.5)

 Minority

268 (13.7)

305 (13.5)

Education level (N, %)^a

< 0.001

 Illiteracy

157 (8.1)

587 (26.3)

 Primary school

503 (26.0)

630 (28.2)

 Middle school

1216 (62.9)

982 (43.9)

 College or above

58 (3.0)

37 (1.7)

Marital status (N, %)^b

< 0.001

 Married

1718 (89.0)

2073 (92.9)

 Other

213 (11.0)

158 (7.1)

Work status (N, %)^c

< 0.001

 Employed

1525 (78.9)

1380 (61.8)

 Unemployed

408 (21.1)

853 (38.2)

Residency (N, %)

0.984

 Urban area

529 (27.1)

610 (27.1)

 Rural area

1426 (72.9)

1642 (72.9)

Total energy (kcal/d, mean ± SD)

2449.2 ± 682.8

2086.6 ± 567.3

< 0.001

Physical activity (MET-h/week, mean ± SD)

148.2 ± 129.0

139.3 ± 114.2

0.019

Sleep duration (N, %)^d

< 0.001

 ≤7 h

498 (26.3)

466 (21.2)

 7–9 h

903 (47.6)

1040 (47.3)

 ≥9 h

496 (26.2)

695 (31.6)

BMI (kg/m²)

24.2 ± 4.5

24.4 ± 4.1

0.091

WC (cm)

85.9 ± 12.9

83.1 ± 12.7

< 0.001

General obesity (N, %)

0.031

 Yes

254 (13.0)

345 (15.3)

 No

1701 (87.0)

1907 (84.7)

Central obesity (N, %)

< 0.001

 Yes

755 (38.6)

1016 (45.1)

 No

1200 (61.4)

1236 (54.9)

Current smoking (N, %)

< 0.001

 Yes

1178 (60.3)

76 (3.4)

 No

777 (39.7)

2176 (96.6)

Alcohol consumption (N, %)

< 0.001

 Yes

1249 (63.9)

194 (8.6)

 No

706 (36.1)

2058 (91.4)