Predictors of tuberculosis treatment outcome at Senkatana clinic in Lesotho

Abstract

INTRODUCTION: tuberculosis (TB) is one of the top ten causes of death and the leading cause from a single infectious agent called Mycobacterium tuberculosis. This study aims to evaluate TB treatment outcomes among patients on first-line anti-tuberculosis treatment and identify the factors associated with successful TB treatment outcomes at Senkatana TB clinic in Lesotho from 2015-2017. METHODS: a registry-based retrospective cohort study of all TB first-line cases recorded from 2015 to 2017 was conducted at Senkatana TB clinic. Data were captured and cleaned in Epi info version 7, and exported into Stata version 14 for analysis. Bivariate logistic regression analysis was used to determine factors associated with TB treatment outcome with p-value <0.05 indicating statistical significance. RESULTS: a total of 1,027 TB patients were registered between 2015 and 2017. Of these, 602 (58.6%) were males and 425 (41.4%) were females, with a mean age of 39 years (SD ±12.5). A total of 843 (82.1%) patients were co-infected with HIV, of which 92.3% (n=778) were on anti-retroviral therapy (ART). The analysis of HIV co-infected with TB patients by age showed that the TB/HIV coinfection rate varies with age (p<0.001). Overall treatment success rate was at 73.4% (n= 754) and 273 (26.6%) had poor treatment outcomes, and 118 (11.5%) patients died. The odds of successful TB treatment outcome were higher in females than males (78.1% vs 70.1%, OR 1.52, 95% CI: 1.14 - 2.03, p=0.004). With regards to age, the odds of successful TB treatment outcome were higher for the 20-24 years age group (88.2% vs 65.3%, OR 3.98, 95% CI: 1.42 - 11.22, P=0.009) and 55-59 years (91.7% vs 65.3%, OR 5.84, 95% CI: 1.56 - 21.88, P=0.009), compared to ≥ 65 years age group. In addition, successful TB treatment outcomes were higher among HIV co-infected TB patients who were taking ART during TB treatment than those not taking ART (75.8% vs 23.8%, OR 11.70, 95% CI: 6.40 - 21.43, P<0.001). Patients observed by family members or friends were more likely to develop treatment success (aOR: 1.87, 95% CI: 1.13 - 3.08). Factory workers in high-risk groups had successful treatment outcomes (aOR: 1.77, 95% CI: 1.04 - 3.01). CONCLUSION: tuberculosis treatment success rate was low and constant over the period of three years. Death rate, loss to follow, and not evaluated were high among our study participants and above the World Health Organization (WHO) target. In unadjusted analyses, female sex, younger age, HIV co-infected taking ART, having a treatment observer, and belonging to high-risk groups, were significantly associated with successful TB treatment outcome.