Active versus passive case finding for tuberculosis in marginalised and vulnerable populations in India: comparison of treatment outcomes

Abstract

Background: Community-based active case finding (ACF) for tuberculosis (TB) implemented among marginalised and vulnerable populations in 285 districts of India resulted in reduction of diagnosis delay and prevalence of catastrophic costs due to TB diagnosis. We were interested to know whether this translated into improved treatment outcomes. Globally, there is limited published literature from marginalised and vulnerable populations on the independent effect of community-based ACF on treatment outcomes when compared to passive case finding (PCF). Objectives: To determine the relative differences in unfavourable treatment outcomes (death, loss-to-follow-up, failure, not evaluated) of ACF and PCF-diagnosed people. Methods: Cohort study involving record reviews and interviews in 18 randomly selected districts. We enrolled all ACF-diagnosed people with new smear-positive pulmonary TB, registered under the national TB programme between March 2016 and February 2017, and an equal number of randomly selected PCF-diagnosed people in the same settings. We used log binomial models to adjust for confounders. Results: Of 572 enrolled, 275 belonged to the ACF and 297 to the PCF group. The proportion of unfavourable outcomes were 10.2% (95% CI: 7.1%, 14.3%) in the ACF and 12.5% (95% CI: 9.2%, 16.7%) in the PCF group (p = 0.468). The association between ACF and unfavourable outcomes remained non-significant after adjusting for confounders available from records [aRR: 0.83 (95% CI: 0.56, 1.21)]. Due to patient non-availability at their residence, interviews were conducted for 465 (81.3%). In the 465 cohort too, there was no association after adjusting for confounders from records and interviews [aRR: 1.05 (95% CI: 0.62, 1.77)]. Conclusion: We did not find significant differences in the treatment outcomes. Due to the wide CIs, studies with larger sample sizes are urgently required. Studies are required to understand how to translate the benefits of ACF to improved treatment outcomes.

Community health workers augment the cascade of TB detection to care in urban slums of two metro cities in India

“…A recently published study from Myanmar reported similar treatment outcomes between cases identi ed actively and passively [28]. Similarly, another study in India did not nd any signi cant difference in the TB treatment outcomes of people detected through active case nding as compared to passive case nding among marginalized and vulnerable populations [29]. Previous studies had the limitation of not adjusting for the potential baseline characteristics and also the follow-up characteristics [28].…”

Does tuberculosis screening improve individual outcomes? A systematic review

“…From 27,270 articles, 18 were eligible [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] (Figure 1 and Table 2); seven were not reported in the previous review [20,[29][30][31][32]36,37]. We only identified n=12/23 (52%) of the outcome indicators sought (Table 1); no studies reported on the remainder.…”

“…Seven observational studies reported on risk groups, including prisoners, [29][30][31][32] migrants, [33] miners, [34] and homeless people. [32,35].…”

“…Four involved established European and South African CXR screening programmes [32][33][34][35]. Three studies from India and Brazil reported on one-off/limited ACF using symptoms [29][30][31].…”

Case finding strategies under National Tuberculosis Elimination Programme (NTEP)

“…It is pertinent to note that before more evidence is generated, patients diagnosed with TB through ACF should be particularly monitored for treatment outcomes when compared from those diagnosed by PCF, as studies in the past had reported variable treatment outcomes. 24 , 25 , 26 …”