Table 1 Baseline characteristics

No. of participants

2805

832

498

432

1043

 Sex: male

1370 (48.84%)

306 (36.78%)

240 (48.19%)

204 (47.22%)

620 (59.44%)

<0.001

 Age (years)

80.00 (73.00, 87.00)

86.00 (78.00, 94.00)

81.00 (74.00, 88.00)

80.00 (73.00, 87.00)

75.00 (71.00, 81.00)

<0.001

Education

<0.001

 No school

1434 (51.12%)

530 (63.70%)

278 (55.82%)

221 (51.16%)

405 (38.83%)

 1 year or more

1371 (48.88%)

302 (36.30%)

220 (44.18%)

211 (48.84%)

638 (61.17%)

Marital status

<0.001

 In marriage

1398 (49.84%)

304 (36.54%)

230 (46.18%)

209 (48.38%)

655 (62.80%)

 Not in marriage

1407 (50.16%)

528 (63.46%)

268 (53.82%)

223 (51.62%)

388 (37.20%)

Income

0.002

 Rich

548 (19.54%)

136 (16.35%)

97 (19.48%)

75 (17.36%)

240 (23.01%)

 Fair/poor

2257 (80.46%)

696 (83.65%)

401 (80.52%)

357 (82.64%)

803 (76.99%)

Residence

<0.001

 Urban

1264 (45.06%)

327 (39.30%)

241 (48.39%)

192 (44.44%)

504 (48.32%)

 Rural

1541 (54.94%)

505 (60.70%)

257 (51.61%)

240 (55.56%)

539 (51.68%)

Living with family

2273 (81.03%)

671 (80.65%)

391 (78.51%)

358 (82.87%)

853 (81.78%)

0.325

 Current smoking

582 (20.75%)

143 (17.19%)

106 (21.29%)

92 (21.30%)

241 (23.11%)

0.018

 Current drinking

553 (19.71%)

119 (14.30%)

94 (18.88%)

90 (20.83%)

250 (23.97%)

<0.001

 Current exercise

1121 (39.96%)

267 (32.09%)

204 (40.96%)

165 (38.19%)

485 (46.50%)

<0.001

Regular intake of foods

 Fruits

1071 (38.18%)

266 (31.97%)

182 (36.55%)

157 (36.34%)

466 (44.68%)

<0.001

 Vegetables

2559 (91.23%)

727 (87.38%)

451 (90.56%)

391 (90.51%)

990 (94.92%)

<0.001

 Meats

2076 (74.01%)

602 (72.36%)

374 (75.10%)

301 (69.68%)

799 (76.61%)

0.025

 Fish

1236 (44.06%)

346 (41.59%)

216 (43.37%)

174 (40.28%)

500 (47.94%)

0.012

 Eggs

1944 (69.30%)

549 (65.99%)

349 (70.08%)

275 (63.66%)

771 (73.92%)

<0.001

 Beans

1527 (54.44%)

425 (51.08%)

262 (52.61%)

225 (52.08%)

615 (58.96%)

0.003

Comorbidities

 Hypertension

841 (29.98%)

227 (27.28%)

151 (30.32%)

141 (32.64%)

322 (30.87%)

0.190

 Diabetes

114 (4.06%)

32 (3.85%)

22 (4.42%)

9 (2.08%)

51 (4.89%)

0.092

 Heart diseases

319 (11.37%)

94 (11.30%)

59 (11.85%)

65 (15.05%)

101 (9.68%)

0.031

 Cerebrovascular diseases

179 (6.38%)

59 (7.09%)

29 (5.82%)

30 (6.94%)

61 (5.85%)

0.640

 Respiratory diseases

302 (10.77%)

115 (13.82%)

40 (8.03%)

58 (13.43%)

89 (8.53%)

<0.001

 Cancer

15 (0.53%)

2 (0.24%)

4 (0.80%)

2 (0.46%)

7 (0.67%)

0.454

ADL disability

295 (10.52%)

184 (22.12%)

35 (7.03%)

50 (11.57%)

26 (2.49%)

<0.001