Two Global Epidemics: The Interrelationship Between Tobacco Dependence and Tuberculosis

Tuberculosis (TB) and tobacco use are two major global health problems that are concentrated within the same populations, particularly in low- and middle-income countries, and mutually reinforce one another. Tobacco smoke weakens host defence against Mycobacterium tuberculosis by impairing mucociliary clearance, alveolar macrophage function, autophagy, antimicrobial responses, and T-cell-mediated immunity. Epidemiological evidence indicates that active smoking increases the risk of TB infection and disease, while clinical studies associate smoking with a higher bacillary burden, cavitary and extensive pulmonary involvement, delayed microbiological conversion, loss to follow-up, recurrence, and mortality. However, the association between smoking and drug resistance is multifactorial, and evidence supporting direct causality remains limited. Repeated contact with healthcare services during TB treatment provides a unique opportunity to deliver tobacco cessation interventions. Integrating brief counselling, behavioural support, pharmacotherapy, and mobile health interventions into TB programmes may improve both cessation success and long-term TB outcomes. This narrative review summarises current evidence on the epidemiology, biological mechanisms, clinical consequences, and integrated control strategies underlying the relationship between tobacco use and TB.