TB Research

Predictors of unsuccessful tuberculosis treatment outcome in Bhutan: A retrospective study using comprehensive national tuberculosis surveillance data.

Thinley Dorji, Karchung Tshering, Lila Adhikari, Thinley Jamtsho, Pavitra Bhujel, Pema Lhaden, Norelle L Sherry, Chantel Lin, et al. (13 authors)

Scientific reports · 2026-02

Abstract

UNLABELLED: Despite the high burden of tuberculosis in Bhutan, data on treatment outcomes are limited. Using a national TB dataset from 2018 to 2021, provided by the National Tuberculosis Reference Laboratory, we conducted a retrospective cohort study to assess treatment outcomes and explore factors associated with unsuccessful TB outcomes. Of the 3,619 patients who received TB treatment, 3,330 had a recorded treatment outcome. Among these, 96.2% (&#x2009;=&#x2009;3,202) had a successful outcome (44.4% (&#x2009;=&#x2009;1,480) were cured and 51.7% (&#x2009;=&#x2009;1,722) completed treatment), and 3.8% (&#x2009;=&#x2009;128) had an unsuccessful outcome (2.8% (&#x2009;=&#x2009;93) died, 0.7% (&#x2009;=&#x2009;23) experienced treatment failure, and 0.4% (&#x2009;=&#x2009;12) were lost to follow-up). Multivariable logistic regression showed patients older than 60 years of age (aOR 4.3; 95% CI 2.09-10.0; p-value&#x2009;<&#x2009;0.001), diagnosed in 2019 (aOR 1.7; 95% CI 1.03&#x2013;2.86; p-value 0.041), 2021 (aOR 1.74; 95% CI 1.03&#x2013;2.97; p-value 0.038), and pulmonary TB (aOR 2.69; 95% CI 1.76&#x2013;4.27; p-value&#x2009;<&#x2009;0.001) were more likely to have an unsuccessful treatment outcome. The proportion of successful TB treatment exceeded the global target rate of 90%, with a low rate of unsuccessful outcomes. Patients with pulmonary TB and elderly patients require active follow-up to ensure their treatment success increases. In-depth studies need to be conducted to understand the circumstances leading to the treatment failures and death.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1038/s41598-026-38023-7.