Cost-effectiveness of a mTB-Tobacco intervention for smoking cessation in people with tuberculosis: an economic evaluation of a cluster randomised controlled trial

Background: High prevalence of smoking tobacco among people with tuberculosis (TB) contribute towards poor outcomes in low- and middle-income countries. A mobile phone-based intervention for smoking cessation among this population (mTB-Tobacco) was evaluated for its cost-effectiveness alongside a cluster randomised controlled trial in Pakistan and Bangladesh. Methods: A two-arm superiority cluster randomised controlled trial with 6 months follow up was conducted between September 2023 and January 2025 in Dhaka, Bangladesh and Punjab, Pakistan. The trial compared the mTB-Tobacco intervention with usual care as control. Participants included those older than or equal to 15 years of age, diagnosed with drug-sensitive pulmonary TB in the past 4 weeks, smoked tobacco daily but willing to quit, and had access to mobile phones. Eighteen TB health facilities (cluster) were randomised to mTB-Tobacco group (n = 720 participants) and nine to usual care (n = 360 participants). The primary analysis was an incremental cost-utility analysis from a public/voluntary sector perspective and primary outcome measure was Quality-Adjusted Life Years (QALYs). Total costs included the costs of TB treatment, costs of intervention or control, and costs of doctor visit and hospital stay. Secondary and sensitivity analyses were also conducted. Findings: Total costs were INT (international dollars) 36. 17 (95% CI 3. 65-65. 81) higher and QALYs were 0. 017 (95% CI 0. 003-0. 030) higher in mTB-Tobacco group than usual care group. Incremental cost-effectiveness ratio was calculated at INT2127. 64 per QALY gained. Estimates by country suggested mTB-Tobacco being unlikely cost-effective in Bangladesh (ICER = INT4261. 11 per QALY gained) but likely cost-effective in Pakistan (ICER = INT1024. 29 per QALY gained). Interpretation: If decision makers in the public/voluntary sector are willing to pay over INT2100 for one additional QALY gained, mTB-Tobacco intervention could likely be cost-effective. Funding: The UK NIHR Global Health Research Unit on Respiratory Health (RESPIRE) (NIHR132826).