The Association Between Tuberculosis and Diabetes Among Adults in Chiapas, Mexico

Objectives: In addition to describing the general epidemiology of tuberculosis (TB) in the Mexican state of Chiapas, the main aim of this study is to answer three research questions: (1) to determine if the prevalence of diabetes mellitus (DM) among TB patients is higher than that of the general population, (2) to compare the sociodemographic characteristics of TB-DM patients versus TB-no DM patients, and (3) to investigate the association between DM and adverse TB treatment outcomes. Methods: We used an official TB surveillance dataset in Mexico to conduct secondary data analysis. Our goal was to investigate the epidemiology of DM and other comorbidities among 5,508 new TB cases aged 18 years or older that were diagnosed in Chiapas between 2010 to 2014. Results: We identified 5,508 TB cases registered by the TB surveillance program between 2010–2014. The average TB incidence over the five-year period was higher in jurisdictions that have borders with Guatemala (29.33 cases per 100,000/year) versus non-border jurisdictions (17.66 cases per 100,000/year). The TB incidence was particularly high in the border jurisdiction of Tapachula (54.25 cases per 100,000/year). Forty-one percent (41.0%) of all the cases were unemployed or not-employed and 45.8% had at least one comorbidity. The most common comorbidities were DM (19.1%) and malnutrition (14.4%). The prevalence of DM was significantly higher that of the general population (p-value \u3c0.0001). The TB-DM patients were more likely to be between 41 and 64 years old (OR = 7.5; 95% CI: 6.3, 9.0) or ≥ 65 years (OR = 3.6; 95% CI: 2.9, 4.6), female (OR = 1.4; 95% CI: 1.3, 1.7), work in non-agriculture, a proxy for socio-economic status (OR = 2.7; 95% CI: 2.1, 3.3), and to be unemployed/ not-employed (OR = 2.7; 95% CI: 2.2, 3.4). After adjusting for sociodemographic characteristics, they were more likely to have pulmonary TB (OR = 3.0; 95% CI: 2.2, 4.3), and be from a jurisdiction that has no borders with Guatemala (OR = 1.3; 95% CI: 1.2, 1.6). We found no significant association between having DM and adverse TB treatment outcomes. Malnutrition was more prevalent among the TB- no DM patients (21.1%), and in municipalities with predominant presence of indigenous people (20.2%). After adjusting for age and sex, patients with unfavorable outcomes (treatment failure or death) were more likely to have malnutrition (OR = 1.6; 95% CI: 1.2, 2.1), and HIV (OR = 7.3; 95% CI: 5.1, 10.4). Conclusion: The epidemiology of TB in Chiapas should be studied in the context of its population. In this state, malnutrition and social risk factors for TB (poverty, migration, and rurality) are key players in the epidemiology of TB, but are mutually exclusive from TB patients with DM. Understanding the double burden of DM and malnutrition on the risk of TB epidemic in Chiapas can be particularly helpful when new strategies to control TB are developed