Noncompliance with directly observed therapy for tuberculosis. Epidemiology and effect on the outcome of treatment

Abstract

Study objectives: To describe the epidemiology and clinical consequences of noncompliance with directly observed therapy (DOT) for treatment of tuberculosis.

Design: Retrospective review.

Setting: An urban tuberculosis control program that emphasizes DOT.

Patients: All patients treated with outpatient DOT from 1984 to 1994.

Measurements and results: We defined noncompliance as follows: (1) missing > or = 2 consecutive weeks of DOT; (2) prolongation of treatment > 30 days due to sporadic missed doses; or (3) incarceration for presenting a threat to public health. Poor outcomes of therapy were defined as a microbiologic or clinical failure of initial therapy, relapse, or death due to tuberculosis. Fifty-two of 294 patients (18%) who received outpatient DOT fulfilled one or more criteria for noncompliance. Using multivariate logistic regression, risk factors for noncompliance were alcohol abuse (odds ratio, 3.0; 95% confidence interval, 1.2 to 7.5; p = 0.02) and homelessness (odds ratio, 3.2; 95% confidence interval, 1.5 to 7.2; p = 0.004). Noncompliant patients had poor outcomes from the initial course of therapy more often than compliant patients: 17 of 52 (32.7%) vs 8 of 242 (3.3%); relative risk was 9.9; 95% confidence interval was 4.5 to 21.7 (p < 0.001).

Conclusions: In an urban tuberculosis control program, noncompliance with DOT was common and was closely associated with alcoholism and homelessness. Noncompliance was associated with a 10-fold increase in the occurrence of poor outcomes from treatment and accounted for most treatment failures. Innovative programs are needed to deal with alcoholism and homelessness in patients with tuberculosis.