A mixed-methods study on impact of silicosis on tuberculosis treatment outcomes and need for TB-silicosis collaborative activities in India.

Globally, silicosis and tuberculosis (TB) have been targeted for elimination by 2030. The study's objectives were to determine the association of silicosis with unfavorable TB treatment outcomes, as well as to explore experts' perspectives on improving treatment outcomes among silico-tuberculosis patients. A retrospective cohort study evaluated TB treatment outcomes in Khambhat block, the western part of India, between 138 patients with silico-tuberculosis and 2610 TB patients without silicosis in February-March 2022. 'Unfavorable TB treatment outcomes' was defined as a patient stopping treatment for at least one month, a positive sputum smear at the end of treatment, or, a patient dying while on treatment. During April-July 2022, fifteen in-depth interviews with experts in the field of silicosis/tuberculosis were audio-recorded, transcribed, and analyzed to generate codes (thematic analysis). On multivariable logistic regression analysis, patients with silico-tuberculosis had a 2.3 (95% CI 1.6-3.4) times higher odds of unfavorable treatment outcomes. The experts recommended collaborative TB-silicosis activities for improving treatment outcomes of patients with silico-tuberculosis. I conclude from the study's findings that silicosis is associated with unfavorable TB treatment outcomes in this study setting. All patients with silicosis should be screened for TB and treated according to national TB program guidelines. All patients with TB who have a history of occupational dust exposure should be evaluated for silicosis and provided appropriate pulmonary/vocational rehabilitation.