Table 2.
Risk Factors for Tuberculosis Amongst Children Less than 19 Years of Age.
| Characteristic | Coprevalent Tuberculosis, Adjusted Odds Ratio (95% CI) | Incident Tuberculosis, Adjusted Hazard Ratio (95% CI) | All Tuberculosis, Adjusted Odds Ratio (95% CI) |
|---|---|---|---|
| All Studies (N = 137,647) | |||
| Male Sex | 1.05 (0.96, 1.13) | 0.99 (0.88, 1.13) | 1.03 (0.94, 1.12) |
| Tuberculosis Infection‡ | |||
| Tuberculin Skin Test Induration ≥10 mm | 18.30 (14.87, 22.52) | 3.34 (2.86, 3.89) | 7.05 (6.27, 7.94) |
| QuantiFERON Gold In-Tube Test, ≥0.35 IU/mL | 21.90 (8.41, 57.06) | 6.47 (2.21, 18.90) | 14.26 (6.94, 29.28) |
| ELISPOT, >8 spot-forming cells* | 7.77 (1.69, 35.63) | 1.91 (0.64, 5.70) | 3.06 (6.94, 29.28) |
| HIV infection | 2.80 (1.62, 4.85) | 5.31 (2.39, 11.81) | 3.55 (2.20, 5.74) |
| Prior Tuberculosis Event | 6.58 (4.40, 9.84) | 3.20 (2.22, 4.51) | 5.30 (3.99, 7.06) |
| Preventive Drug Therapy Regimen† | |||
| All children | … | 0.37 (0.30, 0.47) | … |
| TST+ or IGRA+ | … | 0.15 (0.11, 0.20) | … |
| TST+ or IGRA+, Propensity-Score Matched | … | 0.09 (0.05, 0.15) | … |
| TST- or IGRA- | … | 0.65 (0.40, 1.06) | … |
| TST- or IGRA-, Propensity-Score Matched | … | 0.66 (0.40, 1.10) | … |
| BCG vaccination | |||
| 5–18 years of age | 0.96 (0.70, 1.31) | 0.91 (0.70, 1.18) | 0.90 (0.73, 1.10) |
| <5 years of age | 0.62 (0.45, 0.85) | 0.71 (0.46, 1.08) | 0.64 (0.50, 0.84) |
| Prospective (versus Retrospective) Data Collection | 3.00 (1.45, 6.21) | 3.42 (1.83, 6.42) | 2.38 (1.38, 4.13) |
Abbreviations: TST, Tuberculin Skin Test. IGRA, Interferon Gamma Release Assay. CI, confidence interval. HIV, human immunodeficiency virus. BCG, bacillus Calmette–Guérin.
Both prospective and retrospective studies are included in this analysis. This analysis was repeated with stratification of the prospective/retrospective nature of the data collection; this stratified analysis can be seen in the Supplementary Appendix. Each row represents a distinct statistical model. Each statistical model is adjusted for the variable of interest, baseline child age and sex, whether data was collected prospectively or retrospectively, and the study. The referent group for each row is the opposing value of the listed characteristic. For example, for HIV infection the reference group is children living without HIV. This includes sub-characteristics of variables. For example, the referent group for the sub-characteristic ‘Tuberculin Skin Test Induration ≥10 mm’ under the variable ‘Tuberculosis Infection’ is participants with a ‘Tuberculin Skin Test Induration <10 mm’. Measures of association are reported with 95% confidence intervals for all outcomes. Odds ratios are reported for “All Tuberculosis” which includes both prevalent and incident tuberculosis as one outcome. Prevalent tuberculosis was defined as any diagnosed disease before 90 days from the baseline evaluation. Incident tuberculosis was defined as diagnosed tuberculosis at or after 90 days from the initial contact investigation visit. In this case, contacts with prevalent tuberculosis are not given or protected by preventive therapy.
All tests for tuberculosis infection (tuberculin skin test, QuantiFERON Gold In-Tube test, and ELISpot tests) were administered at baseline. TST/IGRAs may be used in the case definition for tuberculosis, potentially leading to diagnostic bias. Odds Ratios for tests of tuberculosis infection may be understood as “Diagnostic Odds Ratios”.
Administration of preventive therapy, including any type of preventive therapy regimen.
Propensity score matching is based on the age and sex of the contact and whether the study design is prospective or retrospective.
A preventive drug therapy regimen was defined as iniitation of any regimen given and started to children at the baseline visit. These included isoniazid for six months, isoniazid for nine months, rifampin for three months, and rifapentine for three months. Preventive therapy was administered to children at the discretion of each study site and we accepted each study’s decision to administer preventive therapy. Completion of preventive therapy was not reported for almost all studies.