Predictors of noncompliance to pulmonary tuberculosis treatment: An insight from South America

PURPOSE: To investigate the factors associated with a higher risk of noncompliance to tuberculosis (TB) treatment in Porto Alegre, Brazil. METHODS: We identified 478 adult patients for this case-control study undergoing treatment for confirmed pulmonary TB. Cases (noncompliance) were defined as patients who stopped treatment for more than 30 consecutive days (n = 118). Controls were defined as all patients who completed treatment and were cured (n = 360). Factors associated with noncompliance were calculated with unadjusted and adjusted odds ratio (OR). RESULTS: The rate of noncompliance in our study was 25%. The factors of noncompliance after adjustments in the overall population were, in order of magnitude, living in an area of lower income (OR = 4.35, 95%CI: 2.50–7.58), abuse of drugs (OR = 2.73, 95%CI: 1.47–5.09), nonadherence to a previous treatment regimen (OR = 2.1, 95%CI: 1.28–3.45), and history of smoking (OR = 1.72, 95%CI: 1.00–3.00). Age, race, gender, level of education, HIV infection or diabetes status were not associated with a higher risk of noncompliance. In the subgroup of re-treatment cases, poverty (OR = 2.65; 95%CI = 1.06–6.66), smoking history (OR = 2.94; 95%CI = 1.09–7.92), male gender (OR = 3.25; 95%CI = 1.32–8.0), and younger age (OR = 4.3; 95%CI = 1.15–16.07) were also associated with a higher risk of dropout. CONCLUSION: Predictors of poor compliance to TB treatment were low income, abuse of drugs, re-treatment cases and history of smoking.