A Retrospective Comparative Study on Median Time to Sputum Culture Conversion in Multi-Drug Resistant Pulmonary Tuberculosis Patients in Pastoral and Non-Pastoral Settings in Southeast Oromia, Ethiopia

Abstract

Purpose

Sputum culture conversion to negative is an indicator of good interim treatment outcome. Pastoralist community has lesser access to healthcare services. This study aimed to compare the time to culture conversion (TTSCC) between the pastoral and non-pastoral settings and identify its determinants among drug-resistant pulmonary TB patients.

Patients and Methods

Four hundred forty-seven drug-resistant pulmonary TB patients were included from selected hospitals of southeastern Oromia, Ethiopia. Kaplan–Meier model using the Log rank test was fit to compute and compare median TTSCC between study participants from the pastoral and non-pastoral settings. The Cox proportional hazard model was fit to identify factors associated with the TTSCC. Adjusted hazard ratio (AHR) with a 95% confidence interval (CI) was used to report the strength of association. Statistical significance was declared at p < 0.05.

Results

The study participants’ median age (interquartile range) was 29 (24–36) years. The overall median TTSCC among the current study participants was 67 (95% CI, 64–70) days. It was significantly different for patients from the pastoral and non-pastoral settings (p-value <0.001). The median TTSCC for patients from pastoral and non-pastoral settings was 101 (95% CI, 81–121) and 63 (95% CI, 61–64) days. To mention few determinants, patients from the pastoral setting had a 69% lower chance [HR = 0.31 (95% CI 0.24–0.41)] of shorter TTSCC than patients from the non-pastoral setting. Furthermore, patients with baseline body mass index greater than 18.5Kg/M² had a 35% higher chance of shorter TTSCC [HR = 1.35 (95% CI 1.07–1.71)] compared to their counterparts.

Conclusion

The median TTSCC among the study participants from pastoral was longer than those from non-pastoral setting. The pastoral setting, under-nutrition, previous exposure to anti-TB drugs and drug regimen categories were among the notable determinants of the TTSCC among our study participants. Hence, due attention should be given to patients with these determinants during the treatment.

Keywords:

• Ethiopia
• multi-drug tuberculosis
• Oromia
• pastoral setting
• time to sputum culture conversion
• treatment outcome

Acknowledgments

The authors would like to thank Addis Ababa University, College of Medicine and Health Science, for providing financial support for the process of data collection. The authors would also like to thank the selected health facilities leaders and the data collectors for their support, without which this work would not have been practical.

Abbreviations

Am, Amikacin; Bdq, Bedaquiline; Cm, Capreomycin; Cfz, Clofazimine; Cs, Cycloserine; E, Ethambutol; Eto, Ethionamide; Km, Kanamycin; Lfx, Levofloxacin; Lzd, Linezolid; Mfx, Moxifloxacin; PAS, Para-aminosalicylic acid; Pto, Protionamide; Z, Pyrazinamide.

Data Sharing Statement

Data used for this study can be accessed by a formal request from the paper’s corresponding author.

Ethics Approval and Informed Consent

Ethical clearance was obtained from Addis Ababa University Ethical Review board. Upon the ethical approval, a permission letter to conduct the study was obtained from Oromia regional health bureau and submitted to the selected hospitals. Tuberculosis clinic heads gave consent for accessing and extracting data from records at each hospital. The consent included consent for publication. Patient names and identification numbers were removed to ensure the confidentiality of patient information. Instead, anonymous codes were used to identify individual records for data cleaning. In general, this study was conducted in accordance with the Helsinki declaration.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

All authors of this paper confirm that they have no conflicts of interest in this study.