Programmatic nutritional support and tuberculosis treatment outcomes: a natural experiment in West Africa

BACKGROUND: Undernutrition is the leading risk factor for tuberculosis (TB), yet evidence on programmatic nutritional support during treatment is limited. Benin and Togo are neighboring West African counties. Benin provides in-kind food support to all people with drug-susceptible TB; neighbouring Togo does not. This created the opportunity for a natural experiment. METHODS: We conducted a prospective cohort study at 13 sites in Benin and Togo (September 2023-June 2024). We compared recipients of nutritional support with non-recipients, using Beninese non-recipients as an internal comparison. Primary outcomes were ≥5% weight gain at month 2, change in 6-minute walk test (6MWT) distance, and pill-count adherence. We used multivariable regression adjusted for pre-specified covariates. RESULTS: Of 769 participants, 450 received nutritional support and 319 did not. Recipients had higher odds of ≥5% weight gain at month 2 (adjusted odds ratio [aOR] 1.57, 95% CI 1.13-2.19) and ≥10% at month 6 (aOR 1.92, 1.35-2.74), greater 6MWT improvement (adjusted β 40.6 m, 26.5-54.6), and higher adherence (aOR 3.43, 1.81-6.51). Mortality was lower among recipients (aOR 0.32, 0.11-0.93). Sputum conversion and treatment success did not differ. Beninese non-recipients resembled Togolese participants across outcomes. CONCLUSION: Programmatic nutritional support was associated with improved weight gain, functional recovery, adherence, and lower mortality during TB treatment, supporting its integration into national TB programmes.