Table 1.
Baseline Characteristics of UK PREDICT TB Cohort, Stratified by Whether or Not Participants Progressed to Incident TB during Follow-up
| TB Free | TB Progressors | Total | |
|---|---|---|---|
| Sex | |||
| M | 4,673 (49.2) | 56 (52.3) | 4,729 (49.2) |
| F | 4,758 (50.1) | 51 (47.7) | 4,809 (50) |
| Missing | 72 (0.8) | 0 (0) | 72 (0.7) |
| Age, yr | |||
| ≤35 | 5,455 (57.4) | 71 (66.4) | 5,526 (57.5) |
| >35 | 4,026 (42.4) | 36 (33.6) | 4,062 (42.3) |
| Missing | 22 (0.2) | 0 (0) | 22 (0.2) |
| Median (IQR) | 33 (26–47) | 30 (26–39) | 33 (26–47) |
| Ethnicity | |||
| Indian | 3,939 (41.5) | 42 (39.3) | 3,981 (41.4) |
| White | 1,161 (12.2) | 12 (11.2) | 1,173 (12.2) |
| Black African | 1,126 (11.8) | 12 (11.2) | 1,138 (11.8) |
| Mixed | 881 (9.3) | 11 (10.3) | 892 (9.3) |
| Pakistani | 891 (9.4) | 15 (14) | 906 (9.4) |
| Bangladeshi | 712 (7.5) | 4 (3.7) | 716 (7.5) |
| Black Caribbean | 237 (2.5) | 5 (4.7) | 242 (2.5) |
| Other | 315 (3.3) | 5 (4.7) | 320 (3.3) |
| Missing | 241 (2.5) | 1 (0.9) | 242 (2.5) |
| UK Born | |||
| No | 7,917 (83.3) | 91 (85) | 8,008 (83.3) |
| Yes | 1,536 (16.2) | 16 (15) | 1,552 (16.1) |
| Missing | 50 (0.5) | 0 (0) | 50 (0.5) |
| Contact or migrant | |||
| Contact | 4,711 (49.6) | 70 (65.4) | 4,781 (49.8) |
| Migrant | 4,692 (49.4) | 37 (34.6) | 4,729 (49.2) |
| Missing | 100 (1.1) | 0 (0) | 100 (1) |
| BCG vaccinated | |||
| No | 1,457 (15.3) | 13 (12.1) | 1,470 (15.3) |
| Yes | 6,538 (68.8) | 80 (74.8) | 6,618 (68.9) |
| Missing | 1,508 (15.9) | 14 (13.1) | 1,522 (15.8) |
| QFT-GIT | |||
| <0.35 | 6,603 (69.5) | 34 (31.8) | 6,637 (69.1) |
| 0.35–0.69 | 398 (4.2) | 7 (6.5) | 405 (4.2) |
| 0.7–3.99 | 793 (8.3) | 27 (25.2) | 820 (8.5) |
| ≥4 | 552 (5.8) | 26 (24.3) | 578 (6) |
| Indeterminate | 119 (1.3) | 3 (2.8) | 122 (1.3) |
| Missing | 1,038 (10.9) | 10 (9.3) | 1,048 (10.9) |
| T-SPOT.TB | |||
| <5 | 6,257 (65.8) | 33 (30.8) | 6,290 (65.5) |
| 5–7 | 316 (3.3) | 3 (2.8) | 319 (3.3) |
| 8–49 | 876 (9.2) | 30 (28) | 906 (9.4) |
| ≥50 | 416 (4.4) | 27 (25.2) | 443 (4.6) |
| Indeterminate | 119 (1.3) | 2 (1.9) | 121 (1.3) |
| Missing | 1,519 (16) | 12 (11.2) | 1,531 (15.9) |
| BCG-adjusted TST, mm* | |||
| <5 | 5,739 (60.4) | 30 (28) | 5,769 (60) |
| 5–9 | 805 (8.5) | 22 (20.6) | 827 (8.6) |
| 10–14 | 612 (6.4) | 18 (16.8) | 630 (6.6) |
| ≥15 | 576 (6.1) | 31 (29) | 607 (6.3) |
| Missing | 1,771 (18.6) | 6 (5.6) | 1,777 (18.5) |
| Follow-up, yr | |||
| Median (IQR) | 4.69 (3.82–5.52) | 0.51 (0.21–1.34) | 4.68 (3.78–5.51) |
| Total | 9,503 | 107 | 9,610 |
Definition of abbreviations: BCG = bacillus Calmette-Guérin; IQR = interquartile range; QFT-GIT = QuantiFERON Gold-In-Tube; TB = tuberculosis; TST = tuberculin skin test; UK PREDICT = UK Prognostic Evaluation of Diagnostic IFN-γ Release Assays Consortium.
Data are presented as n (%) unless otherwise specified.
*
For participants with previous BCG vaccination (defined by self-report and scar inspection), 10 mm was deducted from the quantitative TST result to adjust for the associated sensitization to BCG (“BCG-adjusted TST”).