Diabetes, undernutrition, migration and indigenous communities: tuberculosis in Chiapas, Mexico

Abstract

We investigated the distribution of comorbidities among adult tuberculosis (TB) patients in Chiapas, the poorest Mexican state, with a high presence of indigenous population, and a corridor for migrants from Latin America. Secondary analysis on 5508 new adult TB patients diagnosed between 2010 and 2014 revealed that the most prevalent comorbidities were diabetes mellitus (DM; 19.1%) and undernutrition (14.4%). The prevalence of DM in these TB patients was significantly higher among middle aged (41-64 years) compared with older adults (⩾65 years) (38.6% vs. 23.2%; P < 0.0001). The prevalence of undernutrition was lower among those with DM, and higher in communities with high indigenous presence. Immigrants only comprised 2% of all TB cases, but were more likely to have unfavourable TB treatment outcomes (treatment failure, death and default) when compared with those born in Chiapas (29.5% vs. 11.1%; P < 0.05). Unfavourable TB outcomes were also more prevalent among the TB patients with undernutrition, HIV or older age, but not DM (P < 0.05). Our study in Chiapas illustrates the challenges of other regions worldwide where social (e.g. indigenous origin, poverty, migration) and host factors (DM, undernutrition, HIV, older age) are associated with TB. Further understanding of these critical factors will guide local policy makers and health providers to improve TB management.

Keywords: Diabetes mellitus (DM); Mexico; indigenous; tuberculosis (TB); undernutrition.

Fig. 1.

Selection of TB cases for data analysis. The initial sample consisted of 6415 records and final analysis was conducted on 5508. We first excluded TB episodes that did not meet the inclusion criteria of age (n = 496), and then excluded an additional 411 episodes that did not correspond to newly diagnosed cases (i.e. entered as treatment failure, relapse, referred or re-entry).

Fig. 2.

Distribution of TB cases in Chiapas by health jurisdiction and border location. Percent of total indicated for each health jurisdiction.

Fig. 3.

Distribution of DM and other comorbidities by sanitary jurisdictions of Chiapas. Border jurisdictions are in black, and non-border jurisdictions are in grey. TG, Tuxtla Gutierrez; VF, Villaflores; TP, Tapachula; TN, Tonala; CM, Comitan; MT, Motozintla; PCH, Pichucalco; PL, Palenque; SCC, San Cristobal de las Casas; OCT, Ocosingo.

Fig. 4.

Distribution of comorbidities by indigenous presence. (a) Proportion of each comorbidity by indigenous presence. (b) Crude and adjusted OR of diabetes or undernutrition by indigenous presence.