Predictors of tuberculosis treatment success under the DOTS program in Namibia

ABSTRACT

Objectives: Optimal treatment success rates are critical to end tuberculosis in Namibia. Despite the scale-up of high quality directly observed therapy short-course strategy (DOTS) in Namibia, treatment success falls short of the global target of 90%. The objective of this study was to ascertain the predictors of treatment success rates under DOTS in Namibia to provide future direction.

Methods: A nation-wide comparative analysis of predictors of treatment success was undertaken. Tuberculosis cases in the electronic tuberculosis register were retrospectively reviewed over a 10-year period, 2004–2016. The patient, programmatic, clinical, and treatment predictors of treatment success were determined by multivariate logistic regression modeling using R software.

Results: 104,603 TB cases were registered at 300 DOTS sites in 37 districts. The 10-year period treatment success rate was 80%, and varied by region (77.2%–89.2%). The patient’s sex and age were not significant predictors. The independent predictors for treatment success as were: Region of DOTS implementation (p=0.001), type of directly observed treatment (DOT) supporter (p<0.001), sputum conversion at 2 months (p=0.013), DOT regimen (p<0.001), cotrimoxazole prophylaxis (p=0.002), and HIV co-infection (p=0.001).

Conclusion: Targeted programmatic, clinical and treatment interventions are required to enhance DOTS treatment success in Namibia. These are now ongoing.

KEYWORDS:

• DOTS program
• TB
• predictors
• effectiveness
• outcomes

Acknowledgments

The authors wish to acknowledge the assistance rendered by the staff at the National Tuberculosis and Leprosy Programme, Ministry of Health and Social Services in accessing of the data from TB registers.

Author contributions

D. Kibuule, R.K. Verbeeck, R. Nunurai, F.Mavungha, E. Ene and T. Rennie help devise the study; D. Kibuule, and E. Ene undertook the data collection and initial analysis; D. Kibuule, R.K. Verbeeck, B.B. Godman, and T. Rennie produced the first manuscript. All authors contributed to successive drafts as well as the update. All authors approved the final paper.

Declaration of interest

E. Ene is an employee of the Anoixis Corporation. In addition, R. Nunurai, F. Mavungha, A. Thomas, R. Amutenya, and G. Gunther are employees of the Ministry of Health and Social Sciences in Namibia for the TB program. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This paper was not funded.