Table 1 Characteristics of Participants^a

Age, mean (SD)

72.55 (0.07)

70.67(0.07)

83.73 (0.05)

< 0.001

Sex (%)

< 0.001

 Male

47.58

50.36

28.48

 Female

52.42

49.64

71.51

Education level (%)

< 0.001

 Illiteracy

51.65

49.29

66.18

 1–6 years

36.23

37.83

26.50

 7–9 years

6.25

6.68

3.63

 10–12 years

3.85

4.10

2.32

 more than 12 years

2.01

2.11

1.38

  < 1000 RMB

24.82

24.04

29.57

< 0.001

 1000–4000 RMB

49.51

49.93

46.94

  > 4000 RMB

26.66

26.02

23.49

Marital status (%)

< 0.001

 Married

60.40

65.55

29.03

 Widowed

37.61

32.37

69.50

 Divorce or Never married

1.99

2.07

1.48

Residence (%)

0.044

 Urban

31.86

24.39

26.28

 Rural

68.14

75.61

73.72

Co-residence (%)

< 0.001

 With family member

85.70

86.91

78.30

 Live alone

12.36

11.72

16.23

 In an institution

1.94

1.37

5.43

Drink status (%)

< 0.001

 Never

66.61

66.40

67.94

 Drinking

24.05

24.74

19.85

 Drinking cessation

9.34

8.87

12.20

Smoke status (%)

< 0.001

 Never

60.35

59.24

67.14

 Smoking

26.10

27.59

17.08

 Smoking cessation

13.55

13.18

15.77

 Hypertension

54.05

53.17

59.35

< 0.001

 Diabetes

2.94

3.17

1.54

< 0.001

 Heart disease

10.04

10.06

9.93

0.865

 Cerebrovascular diseases

6.06

6.10

5.78

0.595

 Parkinson’s disease

0.31

0.28

0.52

0.085

 Dementia

0.56

0.37

1.77

< 0.001

 Cancer

0.51

0.55

0.28

0.074

Disability rate (%)

7.82

5.62

21.23

< 0.001

Katz index group (%)

< 0.001

 A

92.19

94.39

78.77

 B

5.09

4.08

11.23

 C

0.60

0.34

2.22

 D

0.37

0.24

1.16

 E

0.36

0.15

1.65

 F

0.53

0.35

16.4

 G

0.35

0.21

1.20

 Others

0.51

0.25

2.13

Death density(%)

6.01

5.07

14.90

< 0.001