Effects of diabetes mellitus on retreatment of Tuberculosis: A multi-centered case-control study from Bangladesh

Several studies suggested that diabetes mellitus (DM) worsens the tuberculosis (TB) treatment outcome. But information regarding the association of DM with retreatment of TB is very scarce in Bangladesh. Present study aimed to assess the effects of DM on retreatment of TB.

This case-control study was conducted among 254 patients (127 cases and 127 controls) from January 2022 - December 2022. Patients were recruited by purposive sampling from 92 centers of the Diabetic Association of Bangladesh (BADAS). Data were collected by face-to-face interview and record reviewing with the help of semi-structured questionnaire and checklist respectively. Quality of data was maintained in all stages of the study. Data were analyzed by using IBM SPSS software. Informed written consent was taken from each patient prior to the study. Ethical issues were maintained strictly.

Present study matched the age and sex of cases and controls. The study revealed that majority of case (89.0) and controls (97.6) were married. Among cases 78.0 % had DM and among controls 64.6 % had DM. Among diabetic patients, 78.8 % cases' and 64.6 % controls' HbA1C level was not within normal range. The study found that, the number of episodes of previous TB (AOR = 3.088, ρ = 0.019), presence of DM (AOR = 2.817, ρ = 0.012) and uncontrolled HbA1C level (AOR = 2.500, ρ = 0.028) were independently associated with retreatment of TB.

The study found that presence of DM, uncontrolled HbA1C level and multiple episodes of previous TB were the risk factors for retreatment of TB. So, a separate guideline for treatment of TB-DM patients should be established to prevent retreatment cases.