An investigation of the association between obesity, acanthosis nigricans, and fasting serum insulin level in 6--9 year old children living on the El Paso-Juarez U.S.-Mexico border

The objectives of this study were to investigate the relationship between fasting serum insulin levels and Acanthosis Nigricans (AN) (a dermatological condition characterized by hyperpigmentation and thickening of the skin in specific body areas such as the neck and knuckles) and obesity among 6 to 9 year old children. Children were selected at random from a pediatric clinic located on the U.S.-Mexico border. Because none of the children participants had a weight for height at or above the 97th percentile of the CDC growth charts, obesity was defined as weight for height at or above the 95th percentile and at risk of overweight between the 85 th and 95th percentiles of the CDC growth charts. Anthropometrics, blood samples for fasting serum insulin and blood glucose, and a picture of the neck were obtained at baseline (n = 85) and 6 months later (n = 49). None of the children partipating had high fasting serum insulin levels and only 2 children had AN degree 2 (moderately severe). At baseline children with a weight for height at or above the 95th, percentile had 15 units less of insulin than children who weighed less. However, 6 months later this was not confirmed, thus the baseline result is considered to be an anomaly. Eventhough statistical significance was not reached, results showed that children without AN had 5 percentiles lower weight for height than children with AN. The most important recommendation from this study is the need to monitor longitudinal growth in children to characterize the individual child's growth pattern. AN seems to be related to longitudinal growth changes. ^

Effects of health disparities on Helicobacter pylori infection among children on the US-Mexico border

The objective of this study is to determine whether health disparities influence the odds of developing H. pylori infections among the children enrolled in the Pasitos Cohort Study on the US-Mexico border. The study variables were the number of prenatal care visits, ways of transportation, car in household, location of health services and insurance coverage. The study recruited eligible pregnant women to complete baseline questionnaires. Every six months after the birth of the child, infection status is measure by the 13-C urea breath test. Results indicate that having medical insurance consistently decreases the odds of being infected. Children with mothers who went to a private physician had decreased odds of infection compared to those utilizing public clinics, and having a car in the household increased the odds of infection. Limitations include bias due to loss to follow-up and the transient nature of the infection.^

Border intervention by Promotores for type 2 diabetes

Purpose of the study. This study had two components. The first component of the study was the development and implementation of an infrastructure that integrated Promotores who teach diabetes self-management into a community clinic. The second component was a six-month randomized clinical trial (RCT) designed to test the effectiveness of the Promotores in changing knowledge, beliefs, and HbA1c levels among Mexican American patients with type 2 diabetes. ^ Methods. Starfield's adaptation of the Donbedian structure, process, and outcome methodology was used to develop a clinic infrastructure that allowed the integration of Promotores as diabetes educators. The RCT of the culturally sensitive Promotores-led 10-week diabetes self-management program compared the outcomes of 63 patients in the intervention group with 68 patients in a wait-list, usual care control group. Participants were Mexican Americans, at least 18 years of age, with type 2 diabetes, who were patients at a Federally Qualified Health Center on the Texas-Mexico border. At baseline, three months, and six months, data were collected using the Diabetes Knowledge Questionnaire (DKQ, the Health Beliefs Questionnaire (HBQ, and HbA1c levels were drawn by the clinic laboratory. A mixed model methodology was used to analyze the data. ^ Results. The infrastructure to support a Promotores-led diabetes self-management course designed in concert with administration, the physicians, and the CDE, resulted in (1) employment of Promotores to teach diabetes self-management courses; (2) integration of provider and nurse oversight of course design and implementation; (3) management of Promotora training, and the development of teaching competencies and skills; (4) coordination of care through communication and documentation policies and procedures; (5) utilization of quality control mechanisms to maintain patient safety; and (6) promotion of a culturally competent approach to the educational process. The RCT resulted in a significant improvement in the intervention group's DKQ scores over time (F [1, 129] = 4.77, p = 0.0308), and in treatment by time (F [2, 168] = 5.85, p = 0.0035). Neither the HBQ scores nor the HbA1c changed over time. However, the baseline HbA1c was 7.49, almost at the therapeutic level. The DKQ, HBQ, and HbA1c results were significantly affected by age; the DKQ and HbA1c by years with diabetes. ^ Conclusions. The clinic model provides a systematic approach to safely address the educational needs of large numbers of patients with type 2 diabetes who live in communities that suffer from a lack of health care professionals. The Promotores-led diabetes self-management course improved the knowledge of patients with diabetes and may be a culturally sensitive strategy for meeting patient educational needs. The low baseline HbA1c levels in this border community suggested that patients in this Federally Qualified Health Center on the Texas-Mexico border were experiencing good medical management of their diabetes. ^

Drinking water quality perception along the U.S.-Mexico border

Drinking water-related exposures within populations living in the United States-Mexico border region, particularly among Hispanics, is an area that is largely unknown. Specifically, perceptions that may affect water source selection is an issue that has not been fully addressed. This study evaluates drinking water quality perceptions in a mostly Hispanic community living along the United States-Mexico border, a community also facing water scarcity issues. Using a survey that was administered during two seasons (winter and summer), data were collected from a total of 608 participants, of which 303 were living in the United States and 305 in Mexico. A (random) convenience sampling technique was used to select households and those interviewed were over 18 years of age. Statistically significant differences were observed involving country of residence (p=0.002). Specifically, those living in Mexico reported a higher use of bottled water than those living in the United States. Perception factors, especially taste, were cited as main reasons for not selecting unfiltered tap water as a primary drinking water source. Understanding what influences drinking water source preference can aid in the development of risk communication strategies regarding water quality. ^

Helicobacter pylori infection and the effect on growth in a cohort of children in the US/Mexico border

Helicobacter pylori (H. pylori) is an S-shaped or curved gram-negative bacterium that is mostly found in the human stomach. H. pylori causes gastritis in adults and children, which can lead to gastric ulcers or risk of cancer. Transmission of this bacterial infection remains to be unknown but is mostly acquired during childhood. Little is known about the effect H. pylori has on growth in children. Although some studies have reported that H. pylori is associated with subnormal growth, the association of H. pylori with growth retardation and malnutrition is poorly described. Data from this study comes from The Pasitos Cohort Study which draws its population from three border communities which include Socorro and San Elizario in Texas, as well as Ciudad Juarez, Chihuahua, Mexico. Birth documentation was obtained for 803 infants and 472 entered follow-up. This cohort study allowed us to assess the growth of children from 6 months to the seventh anniversary, and describe the prevalence of underweight, short stature and overweight in the study population. We also tested the hypothesis that children in the Pasitos Cohort Study who were ever infected with H. pylori show an increased risk of growth retardation or malnutrition at 66 months of age. Using the 2000 CDC Growth Reference, we found that the mean BMI of the study population increased as children grew older, while the mean of their height for age decreased slightly. The proportion of children who were classified as of short stature was under 5%, while those considered underweight were less than 10% at selected six-months of age intervals. Using the subset of children who were 66 months of age we found that the risk of underweight was higher among those who ever tested positive for H. pylori infection using the urea breath test; however, due to small numbers of children with 'wasting' this difference was not statistically significant. Moreover, since the six cases of under weight occurred among children of low socio-economic status we could not rule out potential confounding. The risk of developing short stature was not different among those ever infected and those who never tested positive for H. pylori infection. ^

Crossing the border for dental care: Factors related to dental health among the south Texas border region

Objectives. The purpose of this thesis is to understand the underlying socioeconomic characteristics affecting dental insurance coverage, yearly dental visits, and factors related to visiting a dentist in Mexico among border region residents. Methods. Using data from the Border Epidemiological Study of Aging, dental utilization in the previous 12 months, dental visits to Mexico, and dental insurance (proxy) were calculated utilizing logistic regression. Three different models were utilized for the dependent variables adjusting for diverse socioeconomic characteristics such as gender, age, marital status, income, education, years of residence in the United States (for immigrants), English proficiency, general health status, employment and dental insurance. Results. After adjustment, diverse variables were significant for the three different models calculated. Conclusion. Although the Mexican health market constitutes a viable option for dental services for border residents, dental insurance and dental yearly visits were lower in this region when compared to national averages. ^

Barriers to cross-border research projects: A prelude to improving professional collaborations between the United States and Mexico

Study objective. This was a secondary data analysis of a study designed and executed in two phases in order to investigate several questions: Why aren't more investigators conducting successful cross-border research on human health issues? What are the barriers to conducting this research? What interventions might facilitate cross-border research? ^ Methods. Key informant interviews and focus groups were used in Phase One, and structured questionnaires in Phase Two. A multi-question survey was created based on the findings of focus groups and distributed to a wider circle of researchers and academics for completion. The data was entered and analyzed using SPSS software. ^ Setting. El Paso, TX located on the U.S-Mexico Border. ^ Participants. Individuals from local academic institutions and the State Department of Health. ^ Results. From the transcribed data of the focus groups, eight major themes emerged: Political Barriers, Language/Cultural Barriers, Differing Goals, Geographic Issues, Legal Barriers, Technology/Material Issues, Financial Barriers, and Trust Issues. Using these themes, the questionnaire was created. ^ The response rate for the questionnaires was 47%. The largest obstacles revealed by this study were identifying a funding source for the project (47% agreeing or strongly agreeing), difficulties paying a foreign counterpart (33% agreeing or strongly agreeing) and administrative changes in Mexico (31% agreeing or strongly agreeing). ^ Conclusions. Many U.S. investigators interested in cross-border research have been discouraged in their efforts by varying barriers. The majority of respondents in the survey felt financial issues and changes in Mexican governments were the most significant obstacles. While some of these barriers can be overcome simply by collaboration among motivated groups, other barriers may be more difficult to remove. Although more evaluation of this research question is warranted, the information obtained through this study is sufficient to support creation of a Cross-Border Research Resource Manual to be used by individuals interested in conducting research with Mexico. ^

Self medication behaviors of illegal immigrants living along the U.S.-Mexico border

Mexican immigrants make up the largest subgroup of Hispanics living in the United States. The largest percentage of illegal immigrants comes from México. As such they are a subpopulation with limited access to health care and social services; their health seeking behaviors including self-medication behaviors that, aside from the intake of antibiotics, have not been studied in depth. The analysis of the data presented sought to document the medication behaviors of illegal immigrants living in El Paso County along the U.S.-México border. Of the 80 participants, 31 were taking medication on a regular basis. Of these, 28 claimed that at least one of the medications had been prescribed by a physician, 13 people had bought at least one of their medications in México, nine participants claimed that they had not paid for at least one of the medications they were taking, ten participants reported that they had skipped the doses of at least one of their medications due to monetary constraints. Participants were also asked if they had purchased medication in México during the year prior to the study, 68 of the 80 (85%) participants had bought 295 pharmaceutical products across the border themselves or through a third party. The most frequently purchased medications were antibiotics (17%), followed by syrups, pomades, creams, eardrops, and cold medicine as a group (15%), followed by analgesics (13%) and other non steroidal anti-inflammatory drugs (12%) and oral hypoglycemic agents (6%). ^

Knowledge of exercise recommendations and energy intake from foods and beverages in relation to exercise behaviors within two Hispanic border communities

This research is a secondary analysis of the Qué Sabrosa Vida population-based cross-sectional study of two predominately Mexican American communities located along the Texas-Mexico border in 2000. There were two aims for this research. The first was to determine the relationship between knowledge of exercise and water recommendations, and exercise behavior and water consumption. The second was to determine the relationship between exercise behavior and percentage of energy consumption from beverages. Chi-square analysis revealed the majority of both populations had adequate knowledge about water and exercise recommendations, although significant percentages of the populations (>40%) did not consume water or exercise in adequate amounts. Knowledge was found to be a component of both behaviors, as it was more prevalent in the adults who exercised and consumed water in adequate amounts. Analysis of variance revealed no significant difference between overall beverage calorie percentage and exercise level (all p-values > 0.05); both regions and genders reported ∼18% of total caloric intake from beverages. There was no disproportionate influence of beverage calories on total caloric intake, after controlling for water consumption and independent of exercise behavior. These findings suggest that overall caloric intake, from both foods and beverages, may be the most influential factor to the energy imbalance contributing to the obesity crisis in these Hispanic border populations. ^

Assessment of markers of medication literacy in a US-Mexico border community

Each year an estimated 180,000 people in the United States (U.S.) die as a result of medication errors, now considered a major public health problem. If a patient cannot correctly act on information related to medication use or "Medication Literacy" there is an increased potential for error. Medication use issues are unique on the US-Mexico border because they include high rates of herbal products and medication products from Mexico as well as issues related to the preferred language (English or Spanish) of the patient. To evaluate the medication literacy in a US-Mexico border community, this retrospective study evaluates 180 subjects representing four diverse economic segments of a metropolitan US-Mexico Border community who have taken a Medication Literacy Assessment. The assessment tool has been created to understand how patients interpret medication information for prescription, over-the-counter, herbal, and Mexican medication product use, and how they problem-solve medication questions. The Medication Literacy Assessment tool specifically assesses document literacy (e.g., prescription labels), prose literacy (e.g., patient leaflets), numeracy (e.g., calculations and measurements) as well as qualitative data related to medication use practices. The main hypothesis of this study is that the ability to interpret and use medications will vary based on education, language (Spanish or English), and recruitment sites (economically diverse communities). The results will provide information to better characterize medication use in a primarily Hispanic population on the US-Mexico border and may be used to influence policy decisions regarding prescription and over-the-counter product information.^

Predictors of diagnostic delay among tuberculosis patients in a U.S.-Mexico border community

Delays in diagnosis of pulmonary tuberculosis have detrimental effects on the health of the ailing patient as well as the people around him or her. These effects are magnified in highly-travelled parts of the world. Identifying factors predictive of diagnostic delay is challenging, as these vary widely by culture and geography. Predictors of delay for tuberculosis patients living in the Northeastern Mexican city of Matamoros, a binationally-transited area, have yet to be described. Using secondary analysis of a retrospective survey, this study sought to identify predictors of diagnostic delay in a sample of culture-positive tuberculosis patients in Matamoros. Sociodemographic, behavioral, and health-related factors were measured and compared. Using bivariate and step-wise regression analyses at an alpha level of 0.05, the author found the following to be statically significant predictors for this sample (R 2=0.171): prior treatment of diabetes, recurrence of tuberculosis, and having ever used cocaine. A question assessing knowledge of immunocompromised subgroups was also identified as a predictor, although its implications are unclear. Notably, the instrument did not distinguish between patient and health system delay. In summary, more research should be conducted in the Matamoros area in order to fully understand the dynamics of delayed diagnosis and its application to public health practice.^

A community-based assessment of the spatiotemporal distribution of influenza in a U.S.-Mexico border county during the spring 2009 novel H1N1 swine-origin influenza A pandemic

This study retrospectively evaluated the spatial and temporal disease patterns associated with influenza-like illness (ILI), positive rapid influenza antigen detection tests (RIDT), and confirmed H1N1 S-OIV cases reported to the Cameron County Department of Health and Human Services between April 26 and May 13, 2009 using the space-time permutation scan statistic software SaTScan in conjunction with geographical information system (GIS) software ArcGIS 9.3. The rate and age-adjusted relative risk of each influenza measure was calculated and a cluster analysis was conducted to determine the geographic regions with statistically higher incidence of disease. A Poisson distribution model was developed to identify the effect that socioeconomic status, population density, and certain population attributes of a census block-group had on that area's frequency of S-OIV confirmed cases over the entire outbreak. Predominant among the spatiotemporal analyses of ILI, RIDT and S-OIV cases in Cameron County is the consistent pattern of a high concentration of cases along the southern border with Mexico. These findings in conjunction with the slight northward space-time shifts of ILI and RIDT cluster centers highlight the southern border as the primary site for public health interventions. Finally, the community-based multiple regression model revealed that three factors—percentage of the population under age 15, average household size, and the number of high school graduates over age 25—were significantly associated with laboratory-confirmed S-OIV in the Lower Rio Grande Valley. Together, these findings underscore the need for community-based surveillance, improve our understanding of the distribution of the burden of influenza within the community, and have implications for vaccination and community outreach initiatives.^

Association of maternal sphinganine:sphingosine ratio and folate levels with neural tube defects along the South Texas border

Neural tube defects (NTDs) remain elevated in Hispanic women along the South Texas Border, despite folate supplementation and folate fortification of cereal products. Missmer et al. examined the relationships between fumonisins, a class of corn mycotoxin, and NTDs in Hispanic women who ate corn tortillas and found increased odds ratios with increasing exposure, as measured by serum sphinganine:sphingosine (sa:so) ratios. This study examined the interactions between categorized maternal serum folate levels and stratified sa:so ratios and the resultant odds ratios of NTDs, stratified by type (anencephaly and spina bifida). The hypothesis was that the above normal folate category would have lower odds ratios of NTDs at given sa:so ratio categories and that there would be a difference in odds ratio patterns for anencephaly and spina bifida. Methods. Data for 406 Hispanic women were obtained from the Missmer case-control study. Sa:so ratios were calculated and subjects were stratified into “below normal,” “normal,” and above normal range for folate. A logistic regression model was applied, controlling for BMI, serum B12, lab batch, and conception date. Results. While OR’s of NTDs increased for increasing sa:so ratios, OR’s for “above normal” folate were not decreased at any sa:so ratio and there was no statistically significant difference between OR’s of anencephaly and spina bifida. Conclusion. Folate does not appear to be protective against the potential teratogenic effect of fumonisins and did not differ in effect on OR’s of NTD by type. More research is necessary to determine the extent of fumonisin exposure in Hispanic women along the South Texas Border.^

A comparison of healthcare access, healthcare utilization and asthma self-management for Hispanic children in border and non-border regions of Texas

The purpose of this culminating experience was to investigate the relationships between healthcare utilization, insurance coverage, and socioeconomic characteristics of children with asthma along the Texas-Mexico Border. A secondary data analysis was conducted on cross-sectional data from the Texas Child Asthma Call-back Survey, a follow-up survey to the random digit dialed Behavior Risk Factor Surveillance Study (BRFSS) conducted between 2006-2009 ( n = 556 adults living in households with a child with asthma).^ The proportion of Hispanic children with asthma in Border areas of Texas was more than twice that of non-Border areas (84.8% vs. 28.8%). Parents in Border areas were less likely to have their own health insurance (OR = 0.251, 95% C.I. = 0.117-0.540) and less likely to complete the survey in English than Spanish (OR = 0.251 95% C.I. = 0.117-0.540) than parents in non-Border areas. No significant socio-economic or health care utilization differences were noted between Hispanic children living in Border areas compared to Hispanic children living in non-Border areas. Children with asthma along the Texas-Mexico Border, regardless of ethnicity and language, have insurance coverage rates, reported cost barriers to care, symptom management, and medication usage patterns similar to those in non-Border areas. When compared to English-speakers, Spanish-speaking parents in Texas as a whole are far less likely to be taught what to do during an asthma attack (50.2% vs. 78.6%).^ Language preference, rather than ethnicity or geographical residence, played a larger role on childhood asthma-related health disparities for children in Texas. Spanish-speaking parents in are less likely to receive adequate asthma self-management education. Investigating the effects of Hispanic acculturation rates and incongruent parent-child health insurance coverage may provide better insight into the health disparities of children along the Texas-Mexico Border.^

Pre-pregnancy obesity on the border and pregnancy complications: A secondary analysis comparing post-natal adult women in Matamoros, Mexico and Cameron County, Texas

Obesity during pregnancy is a serious health concern which has been associated with many adverse health outcomes for both the mother and the infant. In addition, data on the prevalence of obesity and its effects on pregnant women living in the border region are limited. This goal of this study was to examine the prevalence of preconception obesity among women living on each side of the Brownsville-Matamoros border who have just given birth, the relationship between obesity and pregnancy complications for the total population, and these associations by location. Study participants were drawn from a sample (n=947) from the Brownsville-Matamoros Sister City Project which included women from 10 border region hospitals (6 in Matamoros, 4 in Cameron County) who were recruited based on hospital log records indicating they had given birth to a live infant. De-identified data from verbal questionnaires administered within twenty-four hours after birth were analyzed to determine prevalence of preconception obesity on both sides of the border, and associated pregnancy outcomes for women residing in the United States and those in Mexico. Participants with missing height or weight data were excluded from analyses in this study, resulting in a final sample of 727 women. Significant associations were found between pre-pregnancy obesity and adverse pregnancy outcomes (OR=1.85, CI=1.30–2.64), hypertensive conditions (OR=2.76, CI=1.72–4.43), and macrosomia (OR=6.77, CI=1.13–40.57) using the total sample. Comparisons between the United States and Mexico sides of the border showed differences; associations between preconception obesity and adverse pregnancy outcomes were marginally significant among women in the United States (p=0.05), but failed to reach significance within this group for each individual complication. However, significant associations were found between obesity and preeclampsia (OR=3.61, CI=2.14–6.10), as well as obesity and the presence of one or more adverse pregnancy outcome (OR=2.29, CI=1.30–4.02), among women in Mexico. The results from this analysis provide new information specific to women on the Texas and Mexico border, a region that had not previously been studied. These significant associations between preconception obesity and adverse birth outcomes indicate that efforts to prevent obesity should focus on women of childbearing age, especially in Mexico.^