3 Key Takeaways
Plain English Summary- 01Core Finding
We conducted an observational cohort study in Lima, Peru, enrolling 4,500 index participants.
- 02Study Evidence
Tested in a observational cohort study at the real-world cohort stage.
- 03Practical Meaning
Observational cohort findings reveal real-world links, though lifestyle or unmeasured factors cannot be fully ruled out without an RCT.
What This Means for You
Our results show that in this large household cohort, cavitary extent on chest radiograph and cough duration in people with TB were associated with increased TB transmission risk and showed dose-response relationships with TB infection. These simple, readily available indicators may help target preventive interventions in high-burden settings; however, associations with incident TB remain uncertain.
The Discovery
Interrupting TB transmission is a priority in high-burden settings. Identifying highly infectious people with TB may guide targeted interventions. We conducted an observational cohort study in Lima, Peru, enrolling 4,500 index participants. Of the 4,044 people with microbiologically confirmed TB, 3,109 had at least 1 household contact (HHC), yielding 12,767 HHCs. Index participants underwent chest radiograph and TB symptom assessment, from which we derived a modified Bandim TB score. We assessed HHCs for TB infection at baseline and 6 months, and for incident TB disease over 12 months. We analyzed associations between index participant indicators and TB outcomes in HHCs using modified Poisson regression with generalized estimating equations, adjusting for relevant covariates. Among child HHCs, baseline TB infection risk increased with greater cavitary extent (adjusted trend P = .005) and longer cough duration (adjusted trend P = .002), with similar trends at 6 months. Among cavitation categories, multiple-quadrant involvement was associated with the highest baseline infection risk (adjusted prevalence risk ratio, 1.62; 95% CI, 1.10-2.39), but not with incident disease (adjusted cumulative risk ratio, 1.20; 95% CI, 0.56-2.60). Among cough duration categories, ≥ 56 days showed the highest baseline infection risk (adjusted prevalence risk ratio, 1.59; 95% CI, 1.18-2.13), but not incident disease (adjusted cumulative risk ratio, 1.30; 95% CI, 0.85-1.99). The modified Bandim TB score was not associated with transmission risk.
How It Works, Simply
This pulmonology research focuses on airway remodeling & alveolar gas-exchange pathway. Researchers evaluated it using an observational cohort study at the real-world cohort stage of medical research.
3 Key Takeaways
Clinical Takeaways- 01Core Finding
We conducted an observational cohort study in Lima, Peru, enrolling 4,500 index participants.
- 02Study Evidence
Tested in a observational cohort study at the real-world cohort stage.
- 03Practical Meaning
Observational cohort findings reveal real-world links, though lifestyle or unmeasured factors cannot be fully ruled out without an RCT.
Key Numbers
Biological Mechanism & Study Design
Study Design & Cohort
Observational cohort study
Observational cohort study · Real-World Cohort
Biological Pathway & Modality
Airway remodeling & alveolar gas-exchange pathway
Intervention: Pragmatic Clinical indicators of Tuberculosis Transmission Risk: a Household Contact
Experimental Findings & Endpoints
Interrupting TB transmission is a priority in high-burden settings.
Identifying highly infectious people with TB may guide targeted interventions. We conducted an observational cohort study in Lima, Peru, enrolling 4,500 index participants.
Of the 4,044 people with microbiologically confirmed TB, 3,109 had at least 1 household contact (HHC), yielding 12,767 HHCs. Index participants underwent chest radiograph and TB symptom assessment, from which we derived a modified Bandim TB score.
We assessed HHCs for TB infection at baseline and 6 months, and for incident TB disease over 12 months. We analyzed associations between index participant indicators and TB outcomes in HHCs using modified Poisson regression with generalized estimating equations, adjusting for relevant covariates.
Among child HHCs, baseline TB infection risk increased with greater cavitary extent (adjusted trend P = .005) and longer cough duration (adjusted trend P = .002), with similar trends at 6 months. Among cavitation categories, multiple-quadrant involvement was associated with the highest baseline infection risk (adjusted prevalence risk ratio, 1.62; 95% CI, 1.10-2.39), but not with incident disease (adjusted cumulative risk ratio, 1.20; 95% CI, 0.56-2.60).
Among cough duration categories, ≥ 56 days showed the highest baseline infection risk (adjusted prevalence risk ratio, 1.59; 95% CI, 1.18-2.13), but not incident disease (adjusted cumulative risk ratio, 1.30; 95% CI, 0.85-1.99). The modified Bandim TB score was not associated with transmission risk.
Clinical Translation & Practice Context
Our results show that in this large household cohort, cavitary extent on chest radiograph and cough duration in people with TB were associated with increased TB transmission risk and showed dose-response relationships with TB infection.
These simple, readily available indicators may help target preventive interventions in high-burden settings; however, associations with incident TB remain uncertain.
The Bottom Line · Clinical Pearl
“Our results show that in this large household cohort, cavitary extent on chest radiograph and cough duration in people with TB were associated with increased TB transmission risk and showed dose-response relationships with TB infection.”
Published in Chest · Current Stage: Real-World Cohort