The present study aimed to assess the association of outcomes with comprehension, adherence and behavioral characteristics of tuberculosis (TB) patients using fixed-dose combination (FDC) therapy in the city of Contagem, MG, Brazil. This study used standardized questionnaires to collect data. Outcomes included cure in 77.2% (64/ 83), noncompliance with treatment in 20.4% (17/ 83), and absence of organ failure or death cases. The rate of adherence to treatment was high (71.1% - 59/ 83), while the level of comprehension of the treatment was insufficient for the majority of patients (72.3% - 60/ 83). When a greater number of medicines was used, the chance of noncompliance with treatment increased exponentially (p = 0.00 - OR 1.72). Light-skinned black patients, alcoholics and those who live with HIV/ AIDS showed a significant association with noncompliance with treatment (p=0.039 - OR 3.38, p=0.002 - OR 4.68, and p=0.001 - OR 9.68, respectively). Comprehension also presented a significant association with noncompliance with treatment (p=0.01 and OR 5.76 and CI 1.49-22.29). The probability of noncompliance with treatment in the first few months was greater than in the subsequent months. This study demonstrates that if the TB patients had a better understanding of the treatment, the outcome would have been more favorable as regards a proper cure.