The role of Diabetes mellitus comorbidity on Tuberculosis treatment outcomes in Nepal: A prospective cohort study

Aim: The Objective of this study was to assess the effect of Diabetes Mellitus (DM) on treatment outcomes of tuberculosis (TB) patients in the Central Development Region of Nepal. Methods: A prospective cohort study was conducted in central Nepal. The study population of n=408 was consecutively recruited from treatment centers of all 19 districts of central Nepal. The TB cases (n=306) and TB with DM (n=102) cases were followed up for the estimation of blood glucose level, HbA1c level, and sputum examination on 2, 5, and 6 months after TB treatment started. The Generalized Estimating Equation (GEE) was performed to identify the risk ratio among TB and TB with DM cases on treatment outcome. Results: Our study identified that the magnitude of treatment failure among the tuberculosis cases was 19.7% (95% CI: 17.44-21.95). The GEE analysis observed that factors associated with the treatment failure had uncontrolled DM (HbA1C ≥7 %) (adj.RR=5.24, 95% CI: 2.58-10.62, P value <0.001), aged ≥ 45 (adj.RR= 6.13, 95% CI: 2.55-14.76, P value <0.001), had inadequate financial status (adj.RR= 2.33, 95% CI: 1.07-5.06, P value 0.033) and had prior TB (adj.RR=2.33, 95% CI: 1.09-4.97, P value 0.028) respectively. Conclusion: The prevalence of worsening TB treatment among patients with TB and DM was significantly higher than those who had TB only. Poor glycaemic control, increasing age, inadequate financial status, and previous history of tuberculosis were strong predictors of worsening tuberculosis treatment outcomes.