The effect of directly observed therapy on the rates of drug resistance and relapse in tuberculosis

Direct observation of the administration of tuberculosis therapy may reduce the incidence of primary drug resistance, acquired drug resistance and relapse. Drug therapy for tuberculosis is usually effective, but only if patients follow the regimen their doctors prescribe. Failure to comply leads to a recurrence of tuberculosis in many patients, often in a more resistant and harder to treat form. A total of 581 patients with tuberculosis were directly observed by health workers each time they took their medicine. This group's recovery rate was then compared to that of a group of 407 patients who were not observed. There was primary drug resistance in 6.7% of the observed group, compared to 13% of the non-observed patients. Acquired resistance was 2.1% in the observed group and 14% in the non-observed group. The overall relapse rate for the non-observed group was 20.9%, but only 5.5% in the observed group.