A retrospective cohort study: Tuberculosis in four major metrpolitan areas of Texas

Christina R Nunez, The University of Texas School of Nursing at Houston


Background Effective treatment and identification of key factors affecting treatment are crucial in the battle against tuberculosis. In medical practice individuals receive pharmaceutical treatment through directly observed or non-directly observed therapy modes. Directly observed therapy (DOT) is a tuberculosis treatment practice where patients are observed taking their therapy by a trained DOT worker or healthcare provider. Non-directly observed therapy, also known as self-administered therapy, is when patients are responsible for taking their ordered pharmacological regime without supervision of ingestion of their prescribed therapy. The effectiveness of utilizing DOT in the treatment of tuberculosis has been debated in the medical community (Garner, 2003; Macq, Theobald, Dick, & Dembele, 2003; Volmink, 2009). With the significant number of cases of tuberculosis found in Texas it is an ideal location for study. Aims The specific aims of this study were to compare the impact of directly observed therapy (DOT) with non-directly observed therapy (Non-DOT) on culture conversion time and to determine the impact of DOT and Non-DOT on culture conversion time while controlling for demographic variables (Foreign Born, Age, Race) that may impact treatment outcomes. Methods This study analyzed data collected by the Texas Department of State Health Services utilizing a retrospective cohort design. Data analysis for the study was conducted on data collected from 2007-2011. Adults with culture positive pulmonary drug susceptible tuberculosis who were nondiabetic, not HIV positive, residing in the counties of interest (Harris, Travis, Dallas, Fort Worth), and receiving the standard four drug TB regime were included for the study (N=632). Results Survival analysis utilizing Kaplan-Meier analysis demonstrated that individuals on DOT of treatment had a significantly higher number of days to culture-conversion than those on Non-DOT methods (58.0 vs 45.0 , p=.000). The association of mode of therapy with rate of culture conversion was still significant when other variables were controlled. Conclusions Individuals receiving DOT had a longer culture conversion time than those who were on Non-DOT. Further research is indicated to explore the factors impacting those on DOT for the treatment of tuberculosis. Key Words: Tuberculosis, Culture Conversion, Texas, Directly Observed Therapy.

Subject Area

Nursing|Public health

Recommended Citation

Nunez, Christina R, "A retrospective cohort study: Tuberculosis in four major metrpolitan areas of Texas" (2013). Texas Medical Center Dissertations (via ProQuest). AAI3574406.