Table 2.
Baseline characteristics of the study participants by frailty status
| Robust (frailty index ≤0·10; n=291 954) | Prefrail (>0·10 to <0·25; n=205 075) | Frail (frailty index ≥0·25; n=15 694) | Total (n=512 723) | ||
|---|---|---|---|---|---|
| Sociodemographics | |||||
| Sex | |||||
| Men* | 121 947 (58·0%) | 82 619 (39·3%) | 5636 (2·7%) | 210 202 | |
| Women* | 170 007 (56·2%) | 122 456 (40·5%) | 10 058 (3·3%) | 302 521 | |
| Age, years | 48·9 (9·7) | 55·8 (10·4) | 61·7 (9·2) | 52·0 (10·7) | |
| <50 years* | 167 335 (72·6%) | 61 239 (26·6%) | 1816 (0·8%) | 230 390 | |
| 50–64 years* | 102 747 (49·5%) | 97 532 (47·0%) | 7234 (3·5%) | 207 513 | |
| ≥65 years* | 21 872 (29·2%) | 46 304 (61·9%) | 6644 (8·9%) | 74 820 | |
| Place of residence | |||||
| Urban area | 127 309 (43·6%) | 91 827 (44·8%) | 7056 (45·0%) | 226 192 (44·1%) | |
| Rural area | 164 645 (56·4%) | 113 248 (55·2%) | 8638 (55·0%) | 286 531 (55·9%) | |
| Schooling | |||||
| No formal school | 43 418 (17·9%) | 46 712 (19·2%) | 5048 (20·1%) | 95 178 (18·6%) | |
| Primary school (ages 6–11 years) | 88 216 (31·7%) | 714 44 (33·1%) | 5527 (32·9%) | 165 187 (32·2%) | |
| Middle school (ages 12–14 years) | 90 382 (28·2%) | 51 487 (28·5%) | 3005 (29·0%) | 144 874 (28·3%) | |
| High school (ages 15–17 years) | 50 130 (15·8%) | 25 926 (14·2%) | 1452 (12·8%) | 77 508 (15·1%) | |
| College or university | 19 808 (6·4%) | 9506 (5·1%) | 662 (5·2%) | 29 976 (5·8%) | |
| Medical history†‡ | |||||
| Hypertension | 52 531 (20·2%) | 116 194 (52·8%) | 11 863 (67·2%) | 180 588 (35·2%) | |
| Heart disease | 1335 (0·6%) | 10 311 (4·2%) | 3826 (16·3%) | 15 472 (3·0%) | |
| Stroke or transient ischaemic attack | 516 (0·2%) | 6079 (2·4%) | 2289 (9·3%) | 8884 (1·7%) | |
| Emphysema or bronchitis | 1593 (0·6%) | 8492 (4·0%) | 3203 (18·7%) | 13 288 (2·6%) | |
| Tuberculosis | 1876 (0·7%) | 4755 (2·2%) | 1028 (5·3%) | 7659 (1·5%) | |
| Asthma | 372 (0·1%) | 1641 (0·9%) | 793 (6·2%) | 2806 (0·5%) | |
| Peptic ulcer | 5774 (1·9%) | 12 490 (6·2%) | 1751 (11·9%) | 20 015 (3·9%) | |
| Gallstone diseases | 7486 (2·5%) | 20 116 (10·0%) | 3395 (21·0%) | 30 997 (6·0%) | |
| Rheumatoid arthritis | 2041 (0·7%) | 6996 (3·3%) | 1587 (9·3%) | 10 624 (2·1%) | |
| Fracture | 11 172 (3·7%) | 21 697 (10·9%) | 2575 (18·8%) | 35 444 (6·9%) | |
| Neurasthenia | 877 (0·3%) | 3742 (1·8%) | 1080 (7·0%) | 5699 (1·1%) | |
| Diabetes | 3567 (1·3%) | 21 946 (10·0%) | 4787 (26·7%) | 30 300 (5·9%) | |
| Cancer | 420 (0·2%) | 1807 (0·8%) | 351 (1·7%) | 2578 (0·5%) | |
| Chronic kidney disease | 1700 (0·6%) | 4804 (2·5%) | 1071 (7·0%) | 7575 (1·5%) | |
| Symptoms and signs† | |||||
| Short of breath or slows down when walking | 2661 (0·9%) | 21 647 (10·9%) | 8302 (53·1%) | 32 610 (6·4%) | |
| Sleep problem | 22 511 (7·7%) | 54 903 (26·8%) | 8452 (53·7%) | 85 866 (16·7%) | |
| Abnormal frequency of bowel movement | 7869 (2·6%) | 12 611 (6·5%) | 2178 (15·1%) | 22 658 (4·4%) | |
| Body pain or discomfort | 854 (0·3%) | 3694 (2·1%) | 1012 (8·0%) | 5560 (1·1%) | |
| Cough frequently | 3745 (1·2%) | 12 380 (6·6%) | 3445 (25·6%) | 19 570 (3·8%) | |
| Dental problem | 11 885 (6·1%) | 32 592 (12·0%) | 4603 (17·0%) | 49 080 (9·6%) | |
| Low level of physical activity | 26 252 (10·8%) | 66 638 (28·2%) | 9450 (48·6%) | 102 340 (20·0%) | |
| Unintentional weight loss in the past 12 months | 15 248 (4·9%) | 32 726 (17·2%) | 5092 (37·1%) | 53 066 (10·3%) | |
| Have felt sad or depressed in the past 12 months | 2823 (0·9%) | 10 172 (5·9%) | 2543 (23·0%) | 15 538 (3·0%) | |
| Self-reported poor health status | 8413 (2·8%) | 35 391 (17·6%) | 9287 (59·9%) | 53 091 (10·4%) | |
| Physical measurement† | |||||
| BMI <18·5 kg/m2 or ≥28·0 kg/m2 | 21 519 (7·2%) | 49 458 (24·8%) | 5724 (38·6%) | 76 701 (15·0%) | |
| WHR ≥0·95 for men or ≥0·90 for women | 48 336 (17·4%) | 97 182 (45·8%) | 9633 (58·0%) | 155 151 (30·3%) | |
| Heart rate <60 beats per min or >100 beats per min | 12 058 (3·9%) | 24 688 (13·1%) | 3387 (25·7%) | 40 133 (7·8%) | |
| FEV1:FVC <0·7 | 5999 (2·4%) | 17 767 (7·5%) | 3921 (18·3%) | 27 687 (5·4%) | |
| Frailty index | |||||
| Mean frailty index | |||||
| Men | 0·055 (0·028) | 0·148 (0·035) | 0·283 (0·039) | 0·098 (0·062) | |
| Women | 0·055 (0·028) | 0·149 (0·036) | 0·285 (0·040) | 0·101 (0·065) | |
| Frailty index at the 99th centile | |||||
| Men | 0·098 | 0·232 | 0·411 | 0·286 | |
| Women | 0·098 | 0·232 | 0·429 | 0·286 | |
Data are n (%) or mean (SD), unless otherwise stated. Baseline characteristics were adjusted for age, sex, and study area, except in the cases where age, sex, or study area was the independent variable. BMI=body-mass index. FEV1=forced expiratory volume in 1 s. FVC=forced vital capacity. WHR=waist to hip ratio.
*
The percentages for these rows were calculated by use of the total number of participants in different sex or age groups as the denominator.
†
The percentages for these categories represent the proportion of the deficit in different frailty statuses.
‡
The statuses of hypertension and diabetes were based on self-reported diagnosis by a doctor and baseline measurements. Other medical histories were based on self-reports of diagnoses by doctors.