Tuberculosis among economic migrants: A cross‐sectional study of the risk of poor treatment outcomes and impact of a treatment adherence intervention among temporary residents in an urban district in Ho Chi Minh City, Viet Nam

Abstract

Background: Tuberculosis (TB) remains a major cause of avoidable deaths. Economic migrants represent a vulnerable population due to their exposure to medical and social risk factors. These factors expose them to higher risks for TB incidence and poor treatment outcomes. Methods: This cross-sectional study evaluated WHO-defined TB treatment outcomes among economic migrants in an urban district of Ho Chi Minh City, Viet Nam. We measured the association of a patient’s government-defined residency status with treatment success and loss to follow-up categories at baseline and performed a comparative interrupted time series analysis to assess the impact of community-based adherence support on treatment outcomes. Results: Short-term, inter-province migrants experienced lower treatment success (aRR=0.95 [0.92-0.99], p=0.010) and higher loss to follow-up (aOR=1.98 [1.44-2.72], p<0.001) than permanent residents. Intra-province migrants were similarly more likely to be lost to follow-up (aOR=1.86 [1.03-3.36], p=0.041). There was evidence that patients >55 years of age (aRR=0.93 [0.89-0.96], p<0.001), relapse patients (aRR=0.89 [0.84-0.94], p<0.001), and retreatment patients (aRR=0.62 [0.52-0.75], p<0.001) had lower treatment success rates. TB/HIV co-infection was also associated with lower treatment success (aRR=0.77 [0.73-0.82], p<0.001) and higher loss to follow-up (aOR=2.18 [1.55-3.06], p<0.001). The provision of treatment adherence support increased treatment success (IRR(β 6 )=1.07 [1.00, 1.15], p=0.041) and reduced loss to follow-up (IRR(β 6 )=0.17 [0.04, 0.69], p=0.013) in the intervention districts. Loss to follow-up continued to decline throughout the post-implementation period (IRR(β 7 )=0.90 [0.83, 0.98], p=0.019). Conclusions: Economic migrants, particularly those crossing provincial borders, have higher risk of poor treatment outcomes and should be prioritized for tailored adherence support. In light of accelerating urbanization in many regions of Asia, implementation trials are needed to inform evidence-based design of strategies for this vulnerable population.

Trends of Tuberculosis Treatment Outcomes of Notified Cases in Three Refugee Camps in Sudan: A Four-year Retrospective Analysis, 2014–2017

“…As defined in the End TB strategy, the 2020 TB treatment success rate target is at least 90% [2]. Generally, TB treatment success in the refugee population can be affected by factors including less adherence to treatment, death, noncompletion due to lost to follow-up (LTFU), malnutrition, and other coexisting illnesses such as HIV coinfection [8,20,21]. Studies showed lower treatment success rate among refugees in Ethiopia (75.1%) [22] and in refugees hosted in different countries (ranging from 63.6 to 77.5%) [23][24][25][26][27][28].…”

South to North Migration Patterns of Tuberculosis Patients Diagnosed in the Mexican Border with Texas

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