Table 3.
Risk of tuberculosis (TB) among populations with characteristics that might affect exposure and immunity
| Population and definition of positive test result | Among test positive participants | Compared with test negative participants | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| No of cohorts | No of participants | Total (mean) person years follow-up | Active TB events (%)* | TB rate per 1000 person years (95% CI)† | I2 (%) | No of cohorts | Incidence rate ratio (95% CI)† | I2 (%) | ||
| General population‡: | ||||||||||
| TST ≥10 mm | 3 | 33 811 | 249 093 (7.4) | 55 (0.2) | 0.3 (0.1 to 1.1) | 96 | - | - | - | |
| Age <18 years: | ||||||||||
| TST ≥10 mm | 3 | 3388 | 30 642 (9.0) | 26 (0.5) | 0.8 (0.1 to 6.4) | 93 | 1 | 4.9 (2.7 to 8.8) | N/A | |
| Age ≥65 years: | ||||||||||
| QFT-G(IT) positive | 2 | 1879 | 3752.3 (2.0) | 42 (2.2) | 11.2 (8.3 to 15.1) | 0 | 1 | 1.3 (0.1 to 14.1) | N/A | |
| TST ≥10 mm | 2 | 1376 | 3937.5 (2.9) | 14 (1.0) | 3.6 (2.1 to 6.0) | 0 | 2 | 2.2 (0.9 to 5.2) | 0 | |
| Recent immigrant or refugee arrival§: | ||||||||||
| All IGRA positive | 4 | 1597 | 4673 (2.9) | 50 (3.1) | 10.7 (8.1 to 14.1) | 0 | 4 | 10.9 (6.3 to 18.9) | 0 | |
| TST ≥5 mm | 3 | 2145 | 8132 (3.8) | 103 (3.5) | 9.5 (4.3 to 21.0) | 90 | 2 | 6.4 (2.4 to 16.5) | 0 | |
| TST ≥10 mm | 3 | 10 735 | 103 142 (9.6) | 133 (1.7) | 2.7 (1.0 to 7.1) | 96 | 2 | 4.0 (2.1 to 7.9) | 34 | |
| Prisoners: | ||||||||||
| TST ≥10 mm | 3 | 739 | 777 (1.1) | 21 (6.1) | 45.0 (9.0 to 224.6) | 93 | 3 | 31.0 (4.1 to 233.9) | 0 | |
| Occupational risk factor§: | ||||||||||
| All IGRA positive | 8 | 1467 | 3665 (2.5) | 11 (0.7) | 3.0 (1.7 to 5.4) | 0 | 3 | 4.9 (0.5 to 48.3) | 50 | |
| TST ≥5 mm | 3 | 401 | 837 (2.1) | 3 (0.7) | 3.6 (1.2 to 11.1) | 0 | 1 | 0.5 (0.1 to 5.0) | N/A | |
| TST ≥10 mm | 6 | 2696 | 5580 (2.1) | 14 (0.7) | 2.8 (1.3 to 6.1) | 34 | 4 | 1.7 (0.7 to 4.2) | 0 | |
TST=tuberculin skin test; QFT-G(IT)=QuantiFERON Gold-In-Tube; IGRA=interferon-gamma release assay; N/A=not applicable.
*
Percentage represents pooled cumulative incidence estimated from random effects meta-analysis.
†
Pooled estimates using random effects meta-analysis.
‡
Data provided for reference. Populations are from British Columbia and Saskatchewan, Canada, and Florida, USA.
§
See supplementary S1 for a further description of studies comprising these analyses.