Tuberculosis Chemotherapy Outcome in the Littoral Region of Cameroon: A Meta-analysis of Treatment Success Rate between 2014 and 2016

Abstract

Background. Tuberculosis (TB) is a public health concern, especially in resource-constrained countries like Cameroon. TB drug resistance is a major obstacle to control and prevent. Design. Data from 2014 to 2016 on the outcome of anti-TB treatment in the Littoral Region were reviewed manually and analysed using the meta-analysis concept. The treatment success rates (TSR) were the primary outcome used for this study. The heterogeneity statistics (I2) was computed to orientate the choice of the best statistical model (binary fixed effect or random) to compute pooled value of TSR. Results. Using an intention-to-treat analysis, the pooled proportions of HIV-uninfected TB patients successfully cured from TB were low and slightly decreased by 1% between 2014 and 2016. Regarding HIV-infected TB patients, pooled values of TSR were lower than those of their HIV-negative counterparts with values ranging from 71% (95% CI: 63%-83%; I2=71.16%) in 2014 to 68% (95% CI: 58%-79%; I2=70.97%) in 2016. In addition, no heterogeneity was found in three years (I2=0.0%; P value = 1). These cure rates were strongly and negatively correlated with the rates of patients lost to follow-up regardless of the year. In HIV-infected patients, the pooled values of ITT analysis-based treatment success rates were 73% (χ2=13.92, P value = 0.0002), 71% (χ2=7.26, P value = 0.007), and 68% (χ2=8.02, P value = 0.004), respectively. The coverage rates with cotrimoxazole (CTX) gradually increased over year ranging from 78.90% in 2014 to 94.17% in 2016, similar to the coverage rate for ARV therapy that was 60.06% in 2014 against 90% in 2016. A positive and statistically significant correlation was found between the success of the anti-TB therapy in HIV-infected patients and coverage rates with CTX and ARV. Conclusion. An improvement in the reduction of percentage of lost to follow-up and coverage with CTX and ARV therapy could greatly increase chances to efficiently control TB in Cameroon.