Tuberculosis in Brazil

Diabetes is recognized as a significant risk factor in the global post-2015 tuberculosis (TB) strategy, with 13 countries (Afghanistan, Bangladesh, Brazil, Cambodia, China, India, Indonesia, Myanmar, Pakistan, Philippines, Russian Federation, Thailand, and Vietnam) accounting for 60% of new TB cases. Stabilizing diabetes prevalence at 2015 levels in these countries could reduce TB incidence by 20.3% and mortality by 42.7% by 2035, preventing 1.1 million TB deaths over 20 years. The impact of reducing diabetes on TB is sensitive to factors like relapse, progression risks, transmission rates, partial immunity, and TB-specific mortality. However, rising diabetes prevalence and increased BMI might counteract these benefits since, while being overweight or obese lowers TB risk, it increases diabetes risk. There's a pressing need for collaboration between communicable and non-communicable disease sectors to create integrated health policies, involving bidirectional screening for diabetes and TB at primary healthcare centers and adapting the DOTS framework for managing non-communicable diseases in resource-limited settings.[1]

A multicenter prospective observational cohort study titled "RePORT-Brazil" involved individuals aged ≥18 years with culture-confirmed pulmonary tuberculosis (PWTB) and their close contacts. The study enrolled 1038 patients with culture-positive pulmonary tuberculosis, of which 592 had close contacts who participated in the study. It was found that 643 (62%) of the 1038 PWTB had dysglycemia at baseline. Specifically, within the current study, 62% of PWTB exhibited dysglycemia (prediabetes or diabetes mellitus, PDM or DM), with 37.9% having diabetes mellitus. A total of 1573 contacts were followed up. At baseline, only 1% (n = 16) of the close contacts had a confirmed diagnosis of tuberculosis, whereas 42% (n = 658) were diagnosed with latent tuberculosis infection (LTBI). Additionally, only 5% (n = 81) of the tuberculosis contacts were diagnosed with diabetes mellitus. The study concluded that PWTB with dysglycemia were at a higher risk of transmitting M. tuberculosis to their close contacts, as demonstrated in this well-characterized, large, multicenter cohort in Brazil.[2]

References:

1. Pan, S.C., Ku, C.C., Kao, D., Ezzati, M., Fang, C.T. and Lin, H.H., 2015. Effect of diabetes on tuberculosis control in 13 countries with high tuberculosis: a modelling study. The lancet Diabetes & endocrinology, 3(5), pp.323-330. See also: Lin TB Lab

2. Arriaga, M.B., Rocha, M.S., Nogueira, B.M., Nascimento, V., Araújo-Pereira, M., Souza, A.B., Andrade, A.M., Costa, A.G., Gomes-Silva, A., Silva, E.C. and Figueiredo, M.C., 2021. The effect of diabetes and prediabetes on Mycobacterium tuberculosis transmission to close contacts. The Journal of Infectious Diseases, 224(12), pp.2064-2072.