Risk factors associated with default from multidrug-resistant tuberculosis treatment, South Africa, 1999–2001

SETTING: Multidrug-resistant tuberculosis (MDR-TB) treatment centers in five provinces, South Africa.

OBJECTIVES: To estimate the mortality and evaluate risk factors associated with default from MDR-TB treatment.

DESIGN: Using registries and a standardized questionnaire, we conducted a case-control study among patients diagnosed and treated for MDR-TB. Cases were defined as patients who began MDR-TB treatment between 1 October 1999 and 30 September 2001 and defaulted from treatment for more than 2 months; controls were defined as patients who began MDR-TB treatment during the same time and were cured, completed or failed.

RESULTS: After initial identification and reclassification, 269 cases and 401 controls were confirmed eligible for interview. Further investigation revealed that 74 (27%) cases and 44 (10%) controls had died. Among 96 cases located who consented and were interviewed, 70% had defaulted after receiving at least 6 months of treatment. In a multivariate model, the strongest individual risk factors for default included reporting smoking marijuana or mandrax during treatment, and having an unsatisfactory opinion about the attitude of health care workers.

CONCLUSION: Mortality among MDR-TB defaulters was high. Interventions to reduce default from MDR-TB treatment should center on substance abuse treatment, patient education and support and improving provider-patient relationships.