South to North Migration Patterns of Tuberculosis Patients Diagnosed in the Mexican Border with Texas.

The Mexican state of Tamaulipas serves as a migration waypoint into the US. Here, we determined the contribution of immigrants to TB burden in Tamaulipas. TB surveillance data from Tamaulipas (2006-2013) was used to conduct a cross-sectional characterization of TB immigrants (born outside Tamaulipas) and identify their association with TB treatment outcomes. Immigrants comprised 30.8% of TB patients, with > 99% originating from internal Mexican migration. Most migration was from South to North, with cities adjacent to the US border as destinations. Immigrants had higher odds of risk factors for TB [older age (≥ 65 year old, OR 2.4, 95% CI 2.1, 2.8), low education (OR 1.3, 95% CI 1.2, 1.4), diabetes (OR 1.2, 95% CI 1.1, 1.4)], or abandoning treatment (adjusted OR 1.2, 95% CI 1.0, 1.5). There is a need to identify strategies to prevent TB more effectively in Tamaulipas, a Mexican migration waypoint.

Diabetes screen during tuberculosis contact investigations highlights opportunity for new diabetes diagnosis and reveals metabolic differences between ethnic groups.

Type 2 diabetes (T2D) is a prevalent risk factor for tuberculosis (TB), but most studies on TB-T2D have focused on TB patients, been limited to one community, and shown a variable impact of T2D on TB risk or treatment outcomes. We conducted a cross-sectional assessment of sociodemographic and metabolic factors in adult TB contacts with T2D (versus no T2D), from the Texas-Mexico border to study Hispanics, and in Cape Town to study South African Coloured ethnicities. The prevalence of T2D was 30.2% in Texas-Mexico and 17.4% in South Africa, with new diagnosis in 34.4% and 43.9%, respectively. Contacts with T2D differed between ethnicities, with higher smoking, hormonal contraceptive use and cholesterol levels in South Africa, and higher obesity in Texas-Mexico (p < 0.05). PCA analysis revealed striking differences between ethnicities in the relationships between factors defining T2D and dyslipidemias. Our findings suggest that screening for new T2D in adult TB contacts is effective to identify new T2D patients at risk for TB. Furthermore, studies aimed at predicting individual TB risk in T2D patients, should take into account the heterogeneity in dyslipidemias that are likely to modify the estimates of TB risk or adverse treatment outcomes that are generally attributed to T2D alone.

Tuberculosis-diabetes epidemiology in the border and non-border regions of Tamaulipas, Mexico.

Type 2 diabetes mellitus (DM) is a re-emerging risk factor for TB development and adverse TB outcomes. As a follow-up of our previous study in 1998-2004, we reassessed prevalence of DM and its associated factors among 8431 TB patients using surveillance data from 2006 to 2013 for the Mexican state of Tamaulipas, across the border with Texas. Prevalence of DM was 25.2%, with an increase of at least 2.8% over the study period. Newly discovered factors associated with TB-DM (versus no DM) were lower education and higher unemployment (p < 0.001), which are reportedly associated with poorer DM management. At least 15% of the DM patients were newly-diagnosed and younger than those previously diagnosed, showing the importance of early DM diagnosis at TB clinics. TB-DM patients were more likely to have smear-positive, pulmonary (versus extra-pulmonary) and drug-resistant TB (1.9-, 3.8- and 1.4-fold, respectively). During treatment, TB-DM patients were more likely to be smear-positive, and less likely to die or abandon TB treatment. Thus, the increasing prevalence of DM among TB, and its association with low education, features of a more contagious TB, and drug resistance, highlight the need for design of TB management programs in DM patients, blood testing of all new TB patients for DM, and if positive for DM, testing for drug resistance.

Socioeconomic context and the food landscape in Texas: results from hotspot analysis and border/non-border comparison of unhealthy food environments.

PURPOSE: The purpose of this paper is to describe the food landscape of Texas using the CDC's Modified Retail Food Environment (mRFEI) and to make comparisons by border/non-border. METHODS: The Modified Retail Food Environment index (mRFEI (2008)) is an index developed by the CDC that measures what percent of the total food vendors in a census track sell healthy food. The range of values is 0 (unhealthy areas with limited access to fruits and vegetables) to (100-Healthy). These data were linked to 2010 US Census socioeconomic and ethnic concentration data. Spatial analysis and GIS techniques were applied to assess the differences between border and non-border regions. Variables of interest were mRFEI score, median income, total population, percent total population less than five years, median age, % receiving food stamps, % Hispanic, and % with a bachelor degree. RESULTS: Findings from this study reveal that food environment in Texas tends to be characteristic of a "food desert". Analysis also demonstrates differences by border/non-border location and percent of the population that is foreign born and by percent of families who receive food stamps. CONCLUSIONS: Identifying the relationship between socioeconomic disparity, ethnic concentration and mRFEI score could be a fundamental step in improving health in disadvantage communities, particularly those on the Texas-Mexico border.

Cardiovascular disease risk among the Mexican American population in the Texas-Mexico border region, by age and length of residence in United States.

INTRODUCTION: Although the relationship between health behaviors and outcomes such as smoking and obesity with longer residence in the United States among Mexican American immigrants is established, the relationship between length of residency in the United States and risk for cardiovascular disease (CVD) is not fully understood. The objective of this study was to determine the relationship between immigrant status, length of residence in the United States, age, and CVD markers in a sample of Mexican American adults living in Brownsville, Texas. METHODS: We categorized participants in the Cameron County Hispanic Cohort study as immigrants in the United States for 10 years or less, immigrants in the United States for more than 10 years, or born in the United States. We conducted logistic and ordinary least squares regression for self-reported chronic conditions and CVD biomarkers. RESULTS: We found bivariate differences in the prevalence of self-reported conditions and 1 CVD biomarker (low-density lipoprotein cholesterol) by length of residence in the middle (41-64 y) and younger (18-40 y) age groups. After adjusting for covariates, the following varied significantly by immigrant status: stroke and high cholesterol (self-reported conditions) and diastolic blood pressure, systolic blood pressure, total cholesterol, and low-density lipoprotein cholesterol (CVD biomarkers). CONCLUSION: The association between immigrant status, length of residence in the United States, and CVD markers varied. The effect of length of residence in the United States or immigrant status may depend on age and may be most influential in middle or older age.

Region of birth and cardiovascular disease in Mexican Americans living in the Texas-Mexico border.

The study aims to determine whether place of origin has an effect on Mexican American cardiovascular disease (CVD) risk on the South Texas Border. Although many studies have investigated the effect of immigration on Mexican American health, few have considered how region of origin may impact CVD risk. Subjects in the Cameron County Cohort Study were divided into 3 groups according to place of origin: Southern Mexico, Northern Mexico, and U.S. Border States. Descriptive statistics and regression analyses were conducted using CVD biomarkers and self-reported angina, stroke, and elevated blood pressure. Logistic regression revealed that subjects born in U.S. Border States and Northern Mexico states were significantly less likely to have high glucose levels (p < .05) than those born in Southern Mexico. Subjects born in Northern Mexico were less likely to have high triglycerides (p = .05). This study illustrates the importance of considering region of origin in studying the effect of immigration on Mexican American health beyond the standard: number of years in the United States.

Application of a novel method for assessing cumulative risk burden by county.

The purpose of this study is to apply the Human Security Index (HSI) as a tool to detect social and economic cumulative risk burden at a county-level in the state of Texas. The HSI is an index comprising a network of three sub-components or "fabrics"; the Economic, Environmental, and Social Fabrics. We hypothesized that the HSI will be a useful instrument for identifying and analyzing socioeconomic conditions that contribute to cumulative risk burden in vulnerable counties. We expected to identify statistical associations between cumulative risk burden and (a) ethnic concentration and (b) geographic proximity to the Texas-Mexico border. Findings from this study indicate that the Texas-Mexico border region did not have consistently higher total or individual fabric scores as would be suggested by the high disease burden and low income in this region. While the Economic, Environmental, Social Fabrics (including the Health subfabric) were highly associated with Hispanic ethnic concentration, the overall HSI and the Crime subfabric were not. In addition, the Education, Health and Crime subfabrics were associated with African American racial composition, while Environment, Economic and Social Fabrics were not. Application of the HSI to Texas counties provides a fuller and more nuanced understanding of socioeconomic and environmental conditions, and increases awareness of the role played by environmental, economic, and social factors in observed health disparities by race/ethnicity and geographic region.

Impact of Hispanic ethnic concentration and socioeconomic status on obesity prevalence in Texas counties.

The purpose of this study is to determine whether Hispanic ethnic concentration is associated with a higher prevalence of obesity and, if this relationship exists, whether it is affected by the socioeconomic environment. The study uses the Texas Behavioral Risk Factor Surveillance System (BRFSS) linked to 2000 census data to access the relationship between prevalence of obesity, Hispanic ethnic concentration, poverty and level of education at a county-level. The findings suggest that the association of Hispanic ethnic concentration and obesity varies by socioeconomic environment. Although little influence was observed for % poverty, the relationship between Hispanic ethnic concentration and obesity differed by county-level educational attainment. High proportion of residents with a bachelor's degree is associated with a low prevalence of obesity; counties with both high % Hispanic and high % with Bachelor's degrees had the lowest prevalence of obesity. Our results suggest that promoting and improving education, perhaps including training on healthful living, may serve as an effective means of curbing current obesity trends and associated health problems in Hispanic and possibly other ethnic communities.

Using the Framingham Risk Score to evaluate immigrant effect on cardiovascular disease risk in Mexican Americans.

BACKGROUND: This study uses the Framingham Risk Score (FRS) for 10-year cardiovascular disease (CVD) to evaluate differences between Mexican American immigrants and the U.S.-born population. METHODS AND RESULTS: Data from the Cameron County Hispanic Cohort (N=1,559). Average total risk scores were generated by age group for each gender. Regression analysis was conducted adjusting for covariates and interaction effects. Both women and men in the CCHC sample who were long-term immigrant residents (mean FRS scores women 4.2 with p<.001 vs. men 4.0 with p<.001) or born in the U.S. (mean FRS scores women 4.6 with p<.001 vs. men 3.3 with p<.001) had significantly higher risk scores than immigrants who had only been in this country for less than 10 years. The interaction model indicates that differences between immigrant and native-born Mexican Americans are most greatly felt at lowest levels of socioeconomic status for men in the CCHC. CONCLUSIONS: This study suggests that in terms of immigrant advantage in CVD risk, on whom, where, and how the comparisons are being made have important implications for the degree of difference observed.