The disease burden from tuberculosis (TB) and diabetes mellitus (DM) is increasing globally. Current evidence suggests that DM increases the odds of developing TB. This risk is highest in the low-and middle-income countries, where the burden of TB is high. Immune dysfunction due to DM increases the propensity to develop TB. Both DM and TB complicate each other and present enormous clinical challenges. This review article discusses the close interaction between the 2 comorbidities and also advocate for consideration of integration of dual-screening strategies for DM and TB in clinical care especially in areas with high prevalence of both diseases.
Global Burden and Distribution of Tuberculosis and Diabetes MellitusTuberculosis (TB) and diabetes mellitus (DM) are of notable public health importance worldwide. The World Health Organisation estimated approximately 8.7 million incident cases of TB with approximately 1.45 million deaths due to TB in 2011 globally. 1 The International Diabetes Federation in 2011 estimated approximately 366 million people to have DM. This figure is projected to rise to 552 million by 2030. 2 Approximately 183 (50%) million people with DM are undiagnosed worldwide. 2,3 Southeast Asia faces the greatest burden of TB globally with 41.6% of TB patients living in the region, followed by Africa and West Pacific regions both with 20.8% of TB patients. It should be noted that 95% of TB patients globally live in developing countries. 1 The Western Pacific region has the highest burden of DM globally with 36% of the world's DM patients living in this region. However, 80% of patients with diabetes globally live in lowand middle-income countries which also have a considerably high prevalence of TB. Approximately 20% and 5% of the DM patients worldwide live in Southeast Asia and Africa, respectively. 3 In India, a developing country with one of the highest dual prevalence of TB and DM, the estimated prevalence of DM in 2010 was 51 million and it is projected to increase to 70 million by 2025. Approximately 15% of TB cases have been attributable to DM. 3Y5 China, also a country with a high dual prevalence of DM and TB has an estimated 0.9 to 1.2 million TB cases annually. 1 One recent national survey among 46,000 representative adults in China estimated approximately 92 and 148 million people to have DM and pre diabetes, respectively. 6 In Africa, a disproportionate magnitude of people living with both conditions has been documented in most countries. Egypt, for example, has one of the largest proportions of people living with DM in Africa (estimates of 7.5 million people in 2012) 3 but a relatively low number of TB patients (incidence rate of 18/100,000 in 2010) 7 . South Africa, one of the populous African countries has high incidence of TB (981/100,000 in 2010) 7 and low estimates of people living with DM (estimated to be 1.9 million people in 2011), although a rising pattern in the prevalence of DM is being noted. 3 This clearly exemplifies an increased burden of disease from DM and TB mainly ...