Screening for diabetes mellitus in tuberculosis patients in a referral center in Iran

Background: A significant link between diabetes mellitus (DM) and tuberculosis (TB) has been widely demonstrated. DM increases the risk of TB in all aspects. The aims of this study were to assess the prevalence of DM among newly diagnosed TB patients, to screen these patients for DM, and to determine the number needed to screen (NNS) to diagnose new cases of DM. Methods: A prospective cohort descriptive study was carried out in Iranian adults admitted to the National Research Institute of Tuberculosis and Lung Disease from 2012 to 2013 with a new diagnosis of TB. Glycated hemoglobin (HbA1c) and fasting blood glucose (FBG) were measured for all patients. Results: Of the 293 patients included, 101 (34.5%) had DM. DM was newly diagnosed in 45 (19%) patients. The number needed to screen was 5 to identify one new DM case. Age >= 40 years was associated with DM in this population (odds ratio (OR) = 3.91, 95% confidence interval (CI) = 1.47-10.38). Conclusion: Screening for DM should be performed routinely in patients with TB and may improve treatment outcomes.