Effect of complicated, untreated, and uncontrolled diabetes and pre-diabetes on treatment outcome among patients with pulmonary tuberculosis

<bold>Background and aim:</bold> Patients with tuberculosis (TB) and diabetes mellitus (DM) have a higher risk of unfavorable treatment outcomes. We aimed to evaluate the effects of various diabetes statuses on the outcomes among patients with pulmonary TB. <bold>Methods:</bold> Among the patients with pulmonary TB enrolled in the multicenter prospective cohort study of pulmonary TB between 2019 and 2021 in Korea, those with DM were identified. The primary and secondary outcomes were unfavorable outcomes and mortality, respectively. The effect of DM on the outcomes was assessed using multivariable logistic regression analysis. Subgroup analyses were performed to assess the association between various DM statuses (complicated, uncontrolled, untreated DM and prediabetes) and outcomes. <bold>Results:</bold> A total of 1,081 patients were included in the analysis. Patients with DM (adjusted odds ratio [aOR] = 1.64, 95% confidence interval [CI] = 1.09-2.46) and complicated DM (aOR = 1.79, 95% CI = 1.15-2.77) were significantly associated with unfavorable outcome. Based on subgroup analysis, untreated DM at baseline was an independent risk factor for unfavorable outcomes (aOR = 2.72, 95% CI = 1.26–5.61). Complicated (aOR = 2.44, 95% CI = 1.30-4.58) and untreated (aOR = 4.63, 95% CI = 1.69-11.64) diabetes were also significantly associated with mortality. Prediabetes and uncontrolled DM increased unfavorable outcomes and mortality without statistical significance. <bold>Conclusions:</bold> Untreated and complicated DM at the time of TB diagnosis increases the risk of unfavorable outcomes and mortality.