Table 1 Characteristics of the study participants by sex (%)

%

73.9

17.8

2.4

1.1

4.8

100

90.2

6.2

0.8

0.5

2.3

100

Teeth

Number

10.7±10.7

14.7±10.6

16.0±11.5

12.7±11.1

12.9±11.1

11.7±10.8

8.9±10.3

13.0±10.3

16.1±11.1

10.6±12.7

13.3±10.6

9.3±10.4

Age

Years

83.0±10.7

79.9±10.3

76.7±9.4

78.4±10.2

78.7±9.2

82.0±10.7

85.4±12.1

82.1±11.6

79.1±11.1

82.4±14.5

81.1±11.9

85.1±12.1

Age group

Years

65–69

325 (16.1)

100 (20.7)

20 (30.8)

8 (25.8)

30 (22.7)

483 (17.7)

457 (13.8)

49 (21.5)

11 (36.7)

5 (29.4)

21 (25.3)

543 (14.8)

70–74

263 (13.1)

100 (20.7)

16 (24.6)

6 (19.4)

25 (18.9)

410 (15.0)

397 (12.0)

26 (11.4)

1 (3.3)

2 (11.8)

14 (16.9)

440 (12.0)

75–79

275 (13.7)

83 (17.1)

12 (18.5)

7 (22.6)

29 (22.0)

406 (14.9)

413 (12.5)

37 (16.2)

6 (20.0)

2 (11.8)

11 (13.3)

469 (12.8)

80–84

318 (15.8)

63 (13.0)

5 (7.7)

2 (6.5)

13 (9.8)

401 (14.7)

412 (12.5)

36 (15.8)

5 (16.7)

3 (17.6)

7 (8.4)

463 (12.6)

≥ 85

832 (41.3)

138 (28.5)

12 (18.5)

8 (25.8)

35 (26.5)

1,025 (37.6)

1,625 (49.2)

80 (35.1)

7 (23.3)

5 (29.4)

30 (36.1)

1,747 (47.7)

Ethnicity

Han

1,811 (90.0)

465 (96.1)

62 (95.4)

31 (100.0)

129 (97.7)

2,498 (91.7)

3,002 (90.9)

221 (96.9)

29 (96.7)

17 (100.0)

81 (97.6)

3,350 (91.5)

Minority

202 (10.0)

19 (3.9)

3 (4.6)

0 (0.00)

3 (2.3)

227 (8.3)

302 (9.1)

7 (3.1)

1 (3.3)

0 (0.00)

2 (2.4)

312 (8.5)

Residence

City

1,121 (55.7)

325 (67.1)

41 (63.1)

19 (61.3)

87 (65.9)

1,593 (58.5)

1,749 (52.9)

144 (63.2)

15 (50.0)

12 (70.6)

60 (72.3)

1,980 (54.1)

Rural

892 (44.3)

159 (32.9)

24 (36.9)

12 (38.7)

45 (34.1)

1,132 (41.5)

1,555 (47.1)

84 (36.8)

15 (50.0)

5 (29.4)

23 (27.7)

1,682 (45.9)

Geographical region

Northern China

415 (20.6)

103 (21.3)

22 (33.8)

5 (16.1)

71 (53.8)

616 (22.6)

745 (22.5)

36 (15.8)

16 (53.3)

2 (11.8)

52 (62.7)

851 (23.2)

Eastern China

533 (26.5)

175 (36.2)

19 (29.2)

11 (35.5)

7 (5.3)

745 (27.3)

860 (26.0)

87 (38.2)

4 (13.3)

10 (58.8)

5 (6.0)

966 (26.4)

Central China

481 (23.9)

110 (22.7)

10 (15.4)

4 (12.9)

5 (3.8)

610 (22.4)

803 (24.3)

81 (35.5)

3 (10.0)

1 (5.9)

7 (8.4)

895 (24.4)

South-western China

584 (29.0)

96 (19.8)

14 (21.5)

11 (35.5)

49 (37.1)

754 (27.7)

896 (27.1)

24 (10.5)

7 (23.3)

4 (23.5)

19 (22.9)

950 (25.9)

Education level, years

0

538 (26.7)

56 (11.6)

9 (13.8)

2 (6.5)

21 (15.9)

626 (23.0)

2,153 (65.2)

90 (39.5)

9 (30.0)

12 (70.6)

31 (37.3)

2,295 (62.7)

1–6

906 (45.0)

196 (40.5)

21 (32.3)

14 (45.2)

50 (37.9)

1,187 (43.6)

766 (23.2)

70 (30.7)

13 (43.3)

2 (11.8)

32 (38.6)

883 (24.1)

>6

569 (28.3)

232 (47.9)

35 (53.8)

15 (48.4)

61 (46.2)

912 (33.5)

385 (11.7)

68 (29.8)

8 (26.7)

3 (17.6)

20 (24.1)

484 (13.2)

Health

Good

998 (49.6)

263 (54.3)

40 (61.5)

21 (67.7)

68 (51.5)

1,390 (51.0)

1,512 (45.8)

114 (50.0)

19 (63.3)

9 (52.9)

46 (55.4)

1,700 (46.4)

Average

766 (38.1)

158 (32.6)

14 (21.5)

7 (22.6)

55 (41.7)

1,000 (36.7)

1,303 (39.4)

79 (34.6)

7 (23.3)

4 (23.5)

31 (37.3)

1,424 (38.9)

Poor

249 (12.4)

63 (13.0)

11 (16.9)

3 (9.7)

9 (6.8)

335 (12.3)

489 (14.8)

35 (15.4)

4 (13.3)

4 (23.5)

6 (7.2)

538 (14.7)

Household income

1 (poor)

446 (22.2)

61 (12.6)

17 (26.2)

8 (25.8)

15 (11.4)

547 (20.1)

828 (25.1)

27 (11.8)

6 (20.0)

5 (29.4)

6 (7.2)

872 (23.8)

2

453 (22.5)

75 (15.5)

6 (9.2)

7 (22.6)

22 (16.7)

563 (20.7)

756 (22.9)

36 (15.8)

8 (26.7)

1 (5.9)

17 (20.5)

818 (22.3)

3

483 (24.0)

97 (20.0)

14 (21.5)

5 (16.1)

30 (22.7)

629 (23.1)

796 (24.1)

44 (19.3)

7 (23.3)

2 (11.8)

21 (25.3)

870 (23.8)

4

263 (13.1)

98 (20.2)

11 (16.9)

3 (9.7)

30 (22.7)

405 (14.9)

382 (11.6)

42 (18.4)

4 (13.3)

1 (5.9)

23 (27.7)

452 (12.3)

5 (wealthy)

368 (18.3)

153 (31.6)

17 (26.2)

8 (25.8)

35 (26.5)

581 (21.3)

542 (16.4)

79 (34.6)

5 (16.7)

8 (47.1)

16 (19.3)

650 (17.7)

Smoking habit

Never

1,020 (50.7)

145 (30.0)

16 (24.6)

8 (25.8)

46 (34.8)

1,235 (45.3)

3,090 (93.5)

212 (93.0)

28 (93.3)

14 (82.4)

71 (85.5)

3,415 (93.3)

0–14 years

550 (27.3)

165 (34.1)

22 (33.8)

13 (41.9)

49 (37.1)

799 (29.3)

171 (5.2)

13 (5.7)

0 (0.0)

1 (5.9)

10 (12.0)

195 (5.3)

≥15 years

443 (22.0)

174 (36.0)

27 (41.5)

10 (32.3)

37 (28.0)

691 (25.4)

43 (1.3)

3 (1.3)

2 (6.7)

2 (11.8)

2 (2.4)

52 (1.4)

Drinking habit

Never

1,177 (58.5)

232 (47.9)

29 (44.6)

17 (54.8)

58 (43.9)

1,513 (55.5)

2,973 (90.0)

189 (82.9)

25 (83.3)

15 (88.2)

72 (86.7)

3,274 (89.4)

Current drinker

462 (23.0)

165 (34.1)

23 (35.4)

8 (25.8)

47 (35.6)

705 (25.9)

183 (5.5)

23 (10.1)

4 (13.3)

0 (0.0)

4 (4.8)

214 (5.8)

Former drinker

374 (18.6)

87 (18.0)

13 (20.0)

6 (19.4)

27 (20.5)

507 (18.6)

148 (4.5)

16 (7.0)

1 (3.3)

2 (11.8)

7 (8.4)

174 (4.8)

Marital status

Married

1,209 (60.1)

343 (70.9)

50 (76.9)

22 (71.0)

94 (71.2)

1,718 (63.0)

1,041 (31.5)

96 (42.1)

13 (43.3)

9 (52.9)

32 (38.6)

1,191 (32.5)

Unmarried

804 (39.9)

141 (29.1)

15 (23.1)

9 (29.0)

38 (28.8)

1,007 (37.0)

2,263 (68.5)

132 (57.9)

17 (56.7)

8 (47.1)

51 (61.4)

2,471 (67.5)

Brush frequency

Less than once

655 (32.5)

82 (16.9)

13 (20.0)

0 (0.0)

27 (20.5)

777 (28.5)

1,061 (32.1)

32 (14.0)

5 (16.7)

2 (11.8)

14 (16.9)

1,114 (30.4)

Once or more

1,358 (67.5)

402 (83.1)

52 (80.0)

31 (100.0)

105 (79.5)

1,948 (71.5)

2,243 (67.9)

196 (86.0)

25 (83.3)

15 (88.2)

69 (83.1)

2,548 (69.6)

Hypertension

Yes

763 (37.9)

242 (50.0)

31 (47.7)

16 (51.6)

61 (46.2)

1,113 (40.8)

1,445 (43.7)

109 (47.8)

18 (60.0)

6 (35.3)

48 (57.8)

1,626 (44.4)

No

1,250 (62.1)

242 (50.0)

34 (52.3)

15 (48.4)

71 (53.8)

1,612 (59.2)

1,859 (56.3)

119 (52.2)

12 (40.0)

11 (64.7)

35 (42.2)

2,036 (55.6)

Diabetes

Yes

170 (8.4)

67 (13.8)

11 (16.9)

3 (9.7)

18 (13.6)

269 (9.9)

319 (9.7)

33 (14.5)

5 (16.7)

1 (5.9)

15 (18.1)

373 (10.2)

No

1,843 (91.6)

417 (86.2)

54 (83.1)

28 (90.3)

114 (86.4)

2,456 (90.1)

2,985 (90.3)

195 (85.5)

25 (83.3)

16 (94.1)

68 (81.9)

3,289 (89.8)

BMI

<18.5

263 (13.1)

56 (11.6)

5 (7.7)

4 (12.9)

9 (6.8)

337 (12.4)

615 (18.6)

33 (14.5)

2 (6.7)

4 (23.5)

8 (9.6)

662 (18.1)

18.5–24.9

1,285 (63.8)

287 (59.3)

38 (58.5)

21 (67.7)

68 (51.5)

1,699 (62.3)

1,916 (58.0)

138 (60.5)

17 (56.7)

7 (41.2)

43 (51.8)

2,121 (57.9)

≥25

465 (23.1)

141 (29.1)

22 (33.8)

6 (19.4)

55 (41.7)

689 (25.3)

773 (23.4)

57 (25.0)

11 (36.7)

6 (35.3)

32 (38.6)

879 (24.0)

Cardiovascular

Yes

483 (24.0)

126 (26.0)

15 (23.1)

5 (16.1)

41 (31.1)

670 (24.6)

796 (24.1)

65 (28.5)

8 (26.7)

2 (11.8)

27 (32.5)

898 (24.5)

No

1,530 (76.0)

358 (74.0)

50 (76.9)

26 (83.9)

91 (68.9)

2,055 (75.4)

2,508 (75.9)

163 (71.5)

22 (73.3)

15 (88.2)

56 (67.5)

2,764 (75.5)

Sugar frequency

Almost every day

219 (10.9)

64 (13.2)

11 (16.9)

5 (16.1)

24 (18.2)

323 (11.9)

387 (11.7)

22 (9.6)

3 (10.0)

5 (29.4)

15 (18.1)

432 (11.8)

At least per week or month

635 (31.5)

149 (30.8)

17 (26.2)

10 (32.3)

44 (33.3)

855 (31.4)

952 (28.8)

72 (31.6)

13 (43.3)

4 (23.5)

28 (33.7)

1,069 (29.2)

Rarely or occasionally

1,159 (57.6)

271 (56.0)

37 (56.9)

16 (51.6)

64 (48.5)

1,547 (56.8)

1,965 (59.5)

134 (58.8)

14 (46.7)

8 (47.1)

40 (48.2)

2,161 (59.0)

ADL capacity

Non-disabled

1,658 (82.4)

445 (91.9)

60 (92.3)

28 (90.3)

114 (86.4)

2,305 (84.6)

2,533 (76.7)

196 (86.0)

24 (80.0)

15 (88.2)

62 (74.7)

2,830 (77.3)

Disabled

355 (17.6)

39 (8.1)

5 (7.7)

3 (9.7)

18 (13.6)

420 (15.4)

771 (23.3)

32 (14.0)

6 (20.0)

2 (11.8)

21 (25.3)

832 (22.7)