Lack of weight gain and increased mortality during and after treatment among adults with drug-resistant tuberculosis: a retrospective cohort study in Georgia, 2009-2020.

Background: While low body mass index (BMI) is associated with poor tuberculosis (TB) treatment outcomes, the impact of weight gain during TB treatment is unclear. To address this knowledge gap, we assessed whether a lack of weight gain is associated with all-cause mortality during and after TB treatment. Methods: We conducted a retrospective cohort study among adults with newly diagnosed multidrug or extensively drug-resistant (MDR/XDR) pulmonary TB in Georgia between 2009-2020. The exposure was a change in BMI during the first 3-6 months of TB treatment. All-cause mortality during and after TB treatment was assessed using the National Death Registry. We used competing-risk Cox proportional hazard models to estimate adjusted hazard ratios (aHRs) between BMI change and all-cause mortality. Results: Among 720 adult participants, 21% had low BMI (<18.5 kg·m Conclusions: Weight loss during TB treatment (among those with normal baseline BMI) or no weight gain (among those with low baseline BMI) was associated with increased rates of all-cause mortality. Our findings suggest that scaling up weight management interventions among those with M/XDR TB may be beneficial.