Factors associated with unsuccessful treatment outcome for tuberculosis in previously treated patients in Cali, Colombia, during the period 2015-2019

Introduction. The success rates in the treatment of tuberculosis are suboptimal. Objective. To identify associated factors with the lack of success of antituberculosis treatment in patients with a tuberculosis treatment history. Materials and methods. We performed a retrospective, analytical, observational, and cohort study of patients reentering the Mycobacterium program in Cali, Colombia. We included patients over 15 years old with pulmonary tuberculosis between 2015 and 2019 and a history of tuberculosis treatment. Patients with drug-resistant tuberculosis were excluded. Results. A total of 605 patients with a treatment history were included, 60% due to unfinished treatment and 40% due to relapse. Compared to patients reentering due to relapse (ORa=2.34, CI=1.62-3.38), the independent variables associated with treatment failure at discharge were homelessness (ORa=2.45, CI=1.54-3.89), substance dependence (ORa=1.95, CI=1.24-3.05), tuberculosis/HIV coinfection (ORa=1.69, CI=1.00-2.86), diabetes (ORa=1.89, CI=1.29-2.77), and unfinished previous tuberculosis treatment due to follow-up loss, abandonment, or other causes. Programmatic variables favoring treatment success were voluntary HIV testing counseling (p<0.001) and HIV testing (p<0.001). Conclusion. Homelessness, substance dependence, tuberculosis/HIV coinfection, diabetes, and incomplete previous treatment due to loss to follow-up, abandonment, or treatment failure hindered the success of antituberculosis. These characteristics should be identified and addressed during the initial care of patients reentering treatment for tuberculosis.