Diabetes Mellitus among Patients with Tuberculosis Attending Tb Clinics in Dar es Salaam

Abstract

Background: A bi-directional interaction between diabetes mellitus and tuberculosis is well established and has been likened to that between HIV and TB. Whereas HIV screening is standard of care test in sub Saharan Africa TB programs, the same as yet is not true for diabetes mellitus (DM). Sub Saharan Africa, a region with high TB infection rates, is going through an epidemiological transition period with rapidly rising prevalence of diabetes with majority being undiagnosed. We aimed at characterizing TB patients with DM in order to identify factors associated with TB-DM dual disease among patients attending TB treatment clinics in Dar es Salaam. Objective: To determine the prevalence and describe the characteristics associated with diabetes mellitus among patients with tuberculosis attending TB clinics in Dar-es-salaam Methodology: This was a clinic based descriptive cross sectional study among TB patient’s ≥18years. Demographic information was collected and anthropometric measurements taken. Patients were then tested for diabetes using fasting blood glucose followed by 2hrs post prandial glucose (2h-PPG) after a 75g oral glucose load for those with impaired fasting blood glucose. The association between diabetes and clinical characteristics of the patients were examined using logistic regression analyses. Results: A total of 660 TB patients were recruited into the study among whom 25(3.8%) were known diabetics. 39/635 (6.1%) patients were diagnosed to have DM and in additional 147/635(23.1%) patients had impaired fasting blood glucose. Therefore overall 64/660 (9.7%) of subjects had DM. Diabetes mellitus was more prevalent (15.6%) among TB patients aged ≥45years (p=0.01). Other independent risk factors for DM, on multivariate analysis were, a positive family history of DM (OR 2.8, 95%CI 1.52-5.06) p=0.001and overweight (OR 2.5, 95%CI 1.14-5.34) p=0.02. Conclusions: Diabetes Mellitus was a frequent co morbid condition among TB patients in Dar es Salaam and majority of these TB patients had undiagnosed DM. Screening for DM should be advocated among TB patients aged ≥45 years, those who are overweight or obese and with family history of DM.