Table 1.
Baseline demographic and clinical data
| Contacts (n=4861) | Migrants (n=4749) | All participants (n=9610) | |
|---|---|---|---|
| Sex | |||
| Female | 2400 (49·4%) | 2329 (49·0%) | 4729 (49·2%) |
| Male | 2433 (50·1%) | 2376 (50·0%) | 4809 (50·0%) |
| Data missing | 28 (0·6%) | 44 (0·9%) | 72 (0·8%) |
| Ethnicity | |||
| Bangladeshi | 201 (4·1%) | 515 (10·8%) | 716 (7·5%) |
| Black African | 770 (15·8%) | 368 (7·8%) | 1138 (11·8%) |
| Black Caribbean | 235 (4·8%) | 7 (0·2%) | 242 (2·5%) |
| Indian | 1352 (27·8%) | 2629 (55·4%) | 3981 (41·4%) |
| Mixed | 654 (13·5%) | 238 (5·0%) | 892 (9·3%) |
| Other | 194 (4·0%) | 126 (2·7%) | 320 (3·3%) |
| Pakistani | 398 (8·2%) | 508 (10·7%) | 906 (9·4%) |
| White | 942 (19·4%) | 231 (4·9%) | 1173 (12·2%) |
| Data missing | 115 (2·4%) | 127 (2·7%) | 242 (2·5%) |
| Age (years) | |||
| Median (IQR) | 32 (25–44) | 33 (26–51) | 33 (26–47) |
| ≤35 years | 2849 (58·6%) | 2677 (56·4%) | 5526 (57·5%) |
| >35 years | 2005 (41·3%) | 2057 (43·3%) | 4062 (42·3%) |
| Data missing | 7 (0·1%) | 15 (0·3%) | 22 (0·2%) |
| UK born | |||
| No | 3414 (70·2%) | 4594 (96·7%) | 8008 (83·3%) |
| Yes | 1423 (29·3%) | 129 (2·7%) | 1552 (16·2%) |
| Data missing | 24 (0·5%) | 26 (0·6%) | 50 (0·5%) |
| Previous tuberculosis contact before recent exposure | |||
| Yes | 670 (13·8%) | 537 (11·3%) | 1207 (12·6%) |
| No | 4035 (83·0%) | 3988 (84·0%) | 8023 (83·5%) |
| Data missing | 156 (3·2%) | 224 (4·7%) | 380 (4·0%) |
| Previous tuberculosis diagnosis | |||
| Yes | 140 (2·9%) | 213 (4·5%) | 353 (3·7%) |
| No | 4642 (95·5%) | 4428 (93·2%) | 9070 (94·4%) |
| Data missing | 79 (1·6%) | 108 (2·3%) | 187 (2·0%) |
| BCG-vaccination status* | |||
| Vaccinated | 3685 (75·8%) | 2933 (61·8%) | 6618 (68·9%) |
| Not vaccinated | 536 (11·0%) | 934 (19·7%) | 1470 (15·3%) |
| Data missing | 640 (13·2%) | 882 (18·6%) | 1522 (15·8%) |
| BCG vaccination (all)† | |||
| Vaccinated | 4155 (85·5%) | 3791 (79·8%) | 7946 (82·7%) |
| Not vaccinated | 536 (11·0%) | 934 (19·7%) | 1470 (15·3%) |
| Data missing | 170 (3·5%) | 24 (0·5%) | 194 (2·0%) |
| Diabetes | |||
| Yes | 325 (6·7%) | 481 (10·1%) | 806 (8·4%) |
| No | 4519 (93·0%) | 4245 (89·4%) | 8764 (91·2%) |
| Data missing | 17 (0·3%) | 23 (0·5%) | 40 (0·4%) |
| Haematological malignancy | |||
| Yes | 10 (0·2%) | 6 (0·1%) | 16 (0·2%) |
| No | 4815 (99·1%) | 4689 (98·7%) | 95.4 (98·9%) |
| Data missing | 36 (0·7%) | 54 (1·1%) | 90 (0·9%) |
| HIV status (self-reported) | |||
| Positive | 43 (0·9%) | 12 (0·3%) | 55 (0·6%) |
| Negative | 4636 (95·4%) | 4239 (89·3%) | 8875 (92·4%) |
| Data missing | 182 (3·7%) | 498 (10·5%) | 680 (7·1%) |
| Smoking status | |||
| Smoker | 1172 (24·1%) | 635 (13·4%) | 1807 (18·8%) |
| Non-smoker | 3659 (75·3%) | 4078 (85·9%) | 7736 (80·5%) |
| Data missing | 31 (0·6%) | 36 (0·8%) | 67 (0·7%) |
| Previous solid organ transplant | |||
| Yes | 15 (0·3%) | 10 (0·2%) | 25 (0·3%) |
| No | 4813 (99·0%) | 4697 (98·9%) | 9510 (99·0%) |
| Data missing | 33 (0·7%) | 42 (0·9%) | 75 (0·8%) |
| Anti-TNF α (self-report) | |||
| Yes | 17 (0·3%) | 15 (0·3%) | 32 (0·3%) |
| No | 4664 (96·0%) | 4114 (86·6%) | 8778 (91·3%) |
| Data missing | 180 (3·7%) | 620 (13·1%) | 800 (8·3%) |
| Immunosuppressive drug use | |||
| Yes | 43 (0·9%) | 32 (0·7%) | 75 (0·8%) |
| No | 4639 (95·4%) | 4086 (86·0%) | 8725 (90·8%) |
| Data missing | 179 (3·7%) | 631 (13·3%) | 810 (8·4%) |
| Drug or alcohol misuse | |||
| Yes | 166 (3·4%) | 32 (0·7%) | 198 (2·1%) |
| No | 4672 (96·1%) | 4677 (98·5%) | 9349 (97·3%) |
| Data missing | 23 (0·5%) | 40 (0·8%) | 63 (0·7%) |
| Homeless status | |||
| Homeless | 111 (2·3%) | 73 (1·5%) | 184 (1·9%) |
| Not homeless | 4728 (97·3%) | 4642 (97·8%) | 9370 (97·5%) |
| Data missing | 22 (0·5%) | 34 (0·7%) | 56 (0·6%) |
| BMI (kg/m2) | |||
| Mean (SD) | 25·3 (4·9) | 25·0 (4·6) | 25·1 (4·8) |
| Data missing | 368 (7·6%) | 307 (6·5%) | 675 (7·0%) |
| Occupation | |||
| Health-care sector | 257 (5·3%) | 95 (2·0%) | 352 (3·7%) |
| Social or prison sector | 33 (0·7%) | 9 (0·2%) | 42 (0·4%) |
| Laboratory or pathology worker | 11 (0·2%) | 4 (0·1%) | 15 (0·2%) |
| Agricultural or animal care | 0 | 0 | 0 |
| Education | 974 (20·0%) | 708 (14·9%) | 1682 (17·5%) |
| None | 1119 (23·0%) | 1881 (39·6%) | 3000 (31·2%) |
| Other | 2257 (46·4%) | 1691 (35·6%) | 3948 (41·1%) |
| Unknown | 210 (4·3%) | 361 (7·6%) | 571 (5·9%) |
| Travel in previous 2 years‡ | |||
| Yes | 1822 (37·5%) | 1741 (36·7) | 3563 (37·1%) |
| No | 2880 (59·2%) | 2071 (43·6%) | 4951 (51·5%) |
| Data missing | 159 (3·3%) | 937 (19·7%) | 1096 (11·4%) |
| Travel before previous 2 years‡ | |||
| Yes | 1630 (33·5%) | 1403 (29·5%) | 3033 (31·6%) |
| No | 2817 (58·0%) | 2247 (47·3%) | 5064 (52·7%) |
| Data missing | 414 (8·5%) | 1099 (23·1%) | 1513 (15·7%) |
Data are n (%), median (IQR), or mean (SD). BMI=body-mass index. TNF=tumour necrosis factor.
*
Ascertained by scar, medical record, or reliable recall.
†
Includes those assumed to have BCG (BCG data missing and participant non-UK born).
‡
Travelled or lived outside of the UK (not including western Europe, the USA, Canada, and Australia).