Body mass index predictive of sputum culture conversion among MDR-TB patients in Indonesia.

Setting: Programmatic management of drug-resistant tuberculosis at Persahabatan Hospital, Jakarta, Indonesia.

Objective: To evaluate the association between body mass index (BMI) and sputum culture conversion during treatment for multidrug-resistant tuberculosis (MDR-TB).

Design: We conducted a retrospective cohort study of 212 MDR-TB patients. MDR-TB was confirmed using culture in liquid medium and line-probe assay. Patients were treated with a standardised regimen unless they were resistant to any of the drugs tested. Study outcomes were time to culture conversion (primary) and probability of conversion within 4 months (secondary). Data were analysed using Kaplan-Meier curves, discrete time-survival analysis and Poisson regression.

Results: Compared to patients with normal weight (BMI ≥18.5 kg/m(2)), severely underweight patients (BMI <16 kg/m(2)) had longer time to initial conversion (adjusted hazard ratio [aHR] 0.55, 95%CI 0.37-0.84) and a lower probability of sputum culture conversion within 4 months (adjusted relative risk 0.67, 95%CI 0.54-0.83). Other predictors for longer sputum culture conversion were female sex (aHR 0.55, 95%CI 0.39-0.78), resistance to injectables (aHR 0.59, 95%CI 0.42-0.83) and high baseline smear grade (aHR 0.33, 95%CI 0.18-0.60).

Conclusion: Severe underweight was associated with longer time to initial sputum culture conversion among MDR-TB patients.