A Mixed-Methods Study to Examine the Role of Psychosocial Stress and Air Pollution on Hypertension in Mexican-Origin Hispanics.

PURPOSE: Independent and combined effects of air pollution and psychosocial stressors on hypertension, a risk factor for cardiovascular disease, among Hispanics are not well studied. METHODS: We administered a pilot-tested questionnaire on individual- and neighborhood-level psychosocial stressors, developed with community input, to nearly 2500 individuals from the MD Anderson Cancer Center cohort of Mexican-Americans. We used data from local air quality monitors to estimate individual exposures to ozone (O3) and fine particulate matter (PM2.5) for the 12-month period preceding enrollment using inverse distance interpolation. We applied logistic regression models to examine relationships between exposures to psychosocial stressors and air pollution with prevalent hypertension and used stratified analyses to examine the interacting effects of these two exposures on hypertension. RESULTS: There was a positive association between prevalent hypertension and a high frequency of feeling anxious or depressed (prevalence odds ratio (POR) = 1.36, 95% CI [1.06-1.75]) and experiencing aches and pains (POR = 1.29, 95% CI [1.01-1.64]). The odds of having hypertension were also elevated among those worrying about their own health (POR = 1.65, 95% CI [1.30-2.06]) or about not having enough money (POR = 1.27, 95% CI [1.01-1.6]). We observed an inverse association between O3 and hypertension. There was no interaction between psychosocial stressors and O3 on hypertension. CONCLUSION: Our findings add to the evidence of a positive association between individual and family stressors on hypertension among Hispanics and other racial/ethnic groups. Contrary to previous studies reporting positive associations, our results suggest that long-term exposure to O3 may be inversely related to prevalent hypertension.

The Association of Smoking with English and Spanish Language Use as a Proxy of Acculturation Among Mexican-Americans.

To better characterize the relation of acculturation, based on language use, to smoking status among Mexican-Americans, a large study sample from an ongoing cohort of Mexican-American households in Texas was stratified into current smokers and non-smokers. Four language-use groups were created based on Low/High use of Spanish and English, representing different degrees of acculturation. Participants who reported high English but low Spanish use had the highest smoking prevalence (20.1 %), followed by High English/High Spanish (13.6 %), Low English/High Spanish (8.7 %), and Low English/Low Spanish (6.4 %). Current smokers were more likely to be male, have lower than high school education, currently consume alcohol or had consumed alcohol but quit, and report low Spanish/high English use. Consistent with recent models of acculturation, individuals can differ both in their maintenance of the native language and adoption of a new language and both dimensions are important in predicting tobacco use.

Using a Community-Engaged Approach to Develop a Bilingual Survey about Psychosocial Stressors among Individuals of Mexican Origin.

Hypertension is on the rise among Hispanics and is highest among those of Mexican origin. Recent studies have found a positive association between air pollution and blood pressure and hypertension. Moreover, a link between hypertension and adverse socioeconomic conditions is well established. However, less is known about psychosocial stressors, although their impact on coronary heart disease has been shown. To address this gap in the literature, community perspectives of the health consequences of environmental exposures and psychosocial stressors experienced among the Mexican-origin population in Houston, Texas were obtained through participation in focus groups, the establishment of a Neighborhood Council of Advisors (NCA), and the testing of a pilot questionnaire. Taken together, the findings from the community were used to develop a culturally sensitive, bilingual questionnaire for an investigation of the combined effects of environmental and psychosocial stressors on hypertension among individuals of Mexican origin.

The Relationship between Native American Ancestry, Body Mass Index and Diabetes Risk among Mexican-Americans.

Higher body mass index (BMI) is a well-established risk factor for type 2 diabetes, and rates of obesity and type 2 diabetes are substantially higher among Mexican-Americans relative to non-Hispanic European Americans. Mexican-Americans are genetically diverse, with a highly variable distribution of Native American, European, and African ancestries. Here, we evaluate the role of Native American ancestry on BMI and diabetes risk in a well-defined Mexican-American population. Participants were randomly selected among individuals residing in the Houston area who are enrolled in the Mexican-American Cohort study. Using a custom Illumina GoldenGate Panel, we genotyped DNA from 4,662 cohort participants for 87 Ancestry-Informative Markers. On average, the participants were of 50.2% Native American ancestry, 42.7% European ancestry and 7.1% African ancestry. Using multivariate linear regression, we found BMI and Native American ancestry were inversely correlated; individuals with <20% Native American ancestry were 2.5 times more likely to be severely obese compared to those with >80% Native American ancestry. Furthermore, we demonstrated an interaction between BMI and Native American ancestry in diabetes risk among women; Native American ancestry was a strong risk factor for diabetes only among overweight and obese women (OR = 1.190 for each 10% increase in Native American ancestry). This study offers new insight into the complex relationship between obesity, genetic ancestry, and their respective effects on diabetes risk. Findings from this study may improve the diabetes risk prediction among Mexican-American individuals thereby facilitating targeted prevention strategies.

A cross-sectional analysis of polycyclic aromatic hydrocarbons and diesel particulate matter exposures and hypertension among individuals of Mexican origin.

BACKGROUND: Epidemiological studies have found that particulate matter is associated with increases in blood pressure. Yet, less is known about the effects of specific sources or constituents of particulate matter, such as diesel particulate matter or polycyclic aromatic hydrocarbons (PAHs). We evaluated associations between self-reported hypertension and residential air levels of diesel particulate matter and PAHs among individuals of Mexican origin living in a large inner city. METHODS: The Mano a Mano cohort (established in 2001 by the University of Texas MD Anderson Cancer Center) is comprised of individuals of Mexican origin residing in Houston, Texas. Using geographical information systems, we linked modeled annual estimates of PAHs and diesel particulate matter at the census tract level from the 2002 and 2005 U.S. Environmental Protection Agency's National-Scale Air Toxics Assessment to baseline residential addresses of cohort members who enrolled from 2001 to 2003 or 2004 to 2006, respectively. For each enrollment period, we applied mixed-effects logistic regression models to determine associations between diesel particulate matter and PAHs, separately, and self-reported hypertension while adjusting for confounders and the clustering of observations within census tracts and households. RESULTS: The study population consisted of 11218 participants of which 77% were women. The mean participant age at baseline was 41 years. Following adjustment for age, there was a dose-dependent, positive association between PAHs and hypertension (medium exposure, adjusted odds ratio (OR) = 1.09, 95% CI: 0.88-1.36; high exposure, OR = 1.40, 95% CI: 1.01-1.94) for individuals enrolled during 2001-2003; associations were generally similar in magnitude, but less precise, following adjustment for age, gender, smoking, and BMI. No association was detected for the later period. There was no evidence of an association between residential levels of diesel particulate matter and hypertension. CONCLUSIONS: This study builds on a limited number of prior investigations of the association between ambient air levels of PAHs or diesel particulate matter and hypertension by focusing on a relatively young cohort of predominantly adult women of Mexican origin. Future analyses are warranted to explore associations in the cohort using incident hypertension when sufficient data become available and to further examine associations between specific chemical constituents of particulate matter and hypertension in this and other populations.

Family Cohesion and Moderate-to-Vigorous Physical Activity Among Mexican Origin Adolescents: A Longitudinal Perspective.

BACKGROUND: Existing racial/ethnic disparities in physical activity during childhood increase Hispanics' risk of developing chronic diseases, which serves to increase health disparities. This study examined associations of family cohesion and conflict with self-reported moderate-to-vigorous physical activity (MVPA), controlling for psychosocial covariates such as subjective social status, anxiety, and sensation-seeking. METHODS: 1000 Mexican origin adolescents reported their MVPA levels approximately 2 years apart. Psychosocial covariates, family cohesion and conflict were measured at the first assessment. Generalized Linear Models were used to prospectively examine the relationship between family cohesion and conflict and subsequent MVPA based on 711 participants who had low levels of baseline MVPA. RESULTS: 35% of boys and 24% of girls reported adequate MVPA levels at follow-up; girls were less likely to report adequate MVPA (RR = 0.76; 95% CI: 0.61-0.93) than boys. Overall, family cohesion was associated with MVPA (P = .01), but family cohesion was not (P = .41). Gender-based analyses revealed that adequate MVPA was associated with family cohesion (RR = 1.40; 95% CI: 1.03-1.88), sensation seeking (RR = 1.05; 95% CI: 1.00-1.10), and age (RR = 0.85; 95% CI: 0.74-0.98) among girls and with subjective social status (RR = 1.20; 95% CI: 1.08-1.33) among boys. CONCLUSIONS: The family social environment and gender differences should be addressed in health promotion programs targeting MVPA.

Association of acculturation, nativity, and years living in the United States with biobanking among individuals of Mexican descent.

BACKGROUND: Biobanking is the collection of human biospecimens (tissues, blood, and body fluids) and their associated clinical and outcome data. Hispanics are less likely to provide biologic specimens for biobanking. The purpose of this study was to investigate the association of acculturation, nativity status, and years living in the United States with participation in biobanking among individuals of Mexican descent. METHODS: Participants were 19,212 adults of Mexican descent enrolled in an ongoing population-based cohort in Houston, TX. Participants were offered the opportunity to provide a blood, urine, or saliva sample for biobanking. Acculturation was assessed with the bidimensional acculturation scale for Hispanics and scores were categorized into "low acculturation," "bicultural," and "high-acculturation." RESULTS: After multivariable adjustment, we found an increased likelihood of participation in biobanking among individuals classified as "bicultural" as compared with "highly acculturated" individuals [OR, 1.58; 95% confidence intervals (CI), 1.10-2.26]. The associations of nativity status and years living in the United States with biobanking were not statistically significant. After stratifying by gender, the associations of acculturation, nativity status, and years living in the United States with biobanking were not statistically significant. CONCLUSION: Although individuals of Mexican descent who were "bicultural" were more likely to participate in biobanking than individuals who were "highly acculturated," the difference in rates of participation among acculturation categories was small. The high participation rate in biospecimen collection is likely due to extensive community-engaged research efforts. Future studies are warranted to understand individuals' participation in biobanking. IMPACT: Community-engaged research efforts may increase Hispanics' participation in biobanking. Cancer Epidemiol Biomarkers Prev; 23(3); 402-8. ©2014 AACR.

Prostate cancer in Mexican-Americans: identification of risk factors.

BACKGROUND: There is a paucity of information regarding prostate cancer (PCa) risk factors among Hispanics, the fastest-growing ethnic group in the United States. METHODS: This population-based case-control study included 176 Texas men of Mexican descent with PCa and 174 age- and ethnicity-matched controls. Demographic, lifetime occupational history, family history of cancer, lifestyle (e.g., smoking, alcohol, diet, and recreational physical activity) and anthropometric information were collected by personal interviews. Chemical exposure and physical activity were determined using job-exposure matrices for each reported job. RESULTS: Logistic regression models adjusted for relevant covariates were used to evaluate their independent effects. Compared to controls, cases were three times more likely to work in jobs with high agrichemical exposure (OR = 3.44, 95% CI 1.84-6.44), and 54% less likely to work in jobs with moderate/high occupational physical activity (OR = 0.46, 95% CI 0.28-0.77). In analyses stratified by stage, cases with organ-confined PCa were three times more likely to have high agrichemical exposure (OR = 3.39, 9%CI 1.68-6.84), and 56% less likely to have moderate/high levels of occupational physical activity (OR = 0.44, 95% CI 0.26-0.76). Increased risk of being diagnosed with advanced PCa was associated with obesity at time of diagnosis (OR = 2.50, 95% CI 1.20-5.20) and high levels of agrichemical exposure (OR = 4.65, 95% CI 1.97-10.97), but not with occupational physical activity. CONCLUSIONS: This case-control study, the first conducted in a homogeneous Hispanic population, identified modifiable PCa risk factors, such as physical activity and agrichemical exposure, which may be useful in developing interventions for this understudied population.

Maternal BMI and country of birth as indicators of childhood obesity in children of Mexican origin.

OBJECTIVE: The goal of this study was to evaluate the relationship between maternal and childhood BMI at baseline in a group of 5- to 18-year-old children and their mothers, all of whom were of Mexican origin, low socioeconomic status, and enrolled in a cohort study in Houston, TX. RESEARCH METHODS AND PROCEDURES: Using data from 438 mother-child dyads residing in the same household, we completed logistic regression analyses to determine maternal factors associated with the child being overweight or at-risk-for-overweight, after adjusting for the child's gender, age, and level of physical activity and other maternal confounders. RESULTS: Almost one-half of the boys and girls (47% and 44%, respectively) were either overweight or at-risk-for-overweight. Obese mothers were twice as likely to have an overweight and/or at-risk-for-overweight child compared with normal-weight mothers. Women born in the U.S. were twice as likely to have an overweight and/or at-risk-for-overweight child compared with women born in Mexico. In addition, women with less than a high school education were twice as likely to have an overweight child compared with their more educated peers. DISCUSSION: The high prevalence of overweight or at-risk-for-overweight among Mexican-origin children of low socioeconomic status suggests a continued need to develop and implement culturally sensitive preventive interventions for this minority population. Our data also suggest a need to tailor such interventions particularly for children of obese mothers and those born in the U.S.

Birthplace, years of residence in the United States, and obesity among Mexican-American adults.

OBJECTIVE: To evaluate the association between birthplace (Mexico or U.S.) and obesity in men and women and to analyze the relationship between duration of U.S. residency and prevalence of obesity in Mexican immigrants. RESEARCH METHODS AND PROCEDURES: We used cross-sectional data from 7503 adults of Mexican descent residing in Harris County, TX, to evaluate the relationships among BMI, birthplace, and years of residency in the U.S., controlling for demographic characteristics, physical activity level, and acculturation level. RESULTS: U.S.-born adults had an increased risk (between 34% and 65%) of obesity compared with their Mexican-born counterparts. After controlling for recognized confounders and risk factors, this association was maintained in the highly acculturated only. Among highly acculturated obese U.S.-born men, 6% of the cases were attributable to the joint effect of birthplace and acculturation; in women, this proportion was 25%. Among Mexican-born women, there was an increasing trend in mean BMI with increasing duration of residency in the U.S.. Compared with immigrants who had lived in the U.S. for <5 years, Mexican-born women who had resided in the U.S. for >or=15 years had an adjusted BMI mean difference of 2.12 kg/m2 (95% confidence interval, 1.53-2.72). DISCUSSION: Mexican-born men and women have a lower risk of obesity than their U.S.-born counterparts, but length of U.S. residency among immigrants, especially in women, is directly associated with risk of obesity. Development of culturally specific interventions to prevent obesity in recent immigrants may have an important public health effect in this population.

Self-Rated Health Among Adult Women of Mexican Origin.

Self-rated health (SRH), a consistent predictor of mortality among diverse populations, is sensitive to health indicators and social factors. American-born Hispanics report better SRH than their foreign-born counterparts but simultaneously report poorer health indicators and have shorter life expectancy. Using a matched prospective cross-sectional design, we analyzed data from 631 age-matched pairs of women, born in the United States or Mexico, enrolled in a cohort study based in Houston, Texas. Our first goal was to describe the relationships between SRH and health behaviors, physician-diagnosed chronic conditions, acculturation, and socioeconomic status (SES) by birthplace. Our second goal was to investigate the relative influence of SES, acculturation, health behaviors, and physician-diagnosed conditions in explaining expected differences in SRH between the two groups. Number of chronic conditions reported, particularly depression, more strongly influenced SRH than SES, acculturation, or reported health risk behaviors and the influence of birthplace is accounted for by these factors.

Effects of nativity, age at migration, and acculturation on smoking among adult Houston residents of Mexican descent.

OBJECTIVES: We investigated differences in smoking behaviors between US-and Mexican-born ever smokers and examined the influence of US culture on smoking initiation. METHODS: Participants were 5030 adults of Mexican descent enrolled in an ongoing population-based cohort in Houston, Tex. RESULTS: More men than women reported current smoking; rates among US-born women were higher than those among Mexican-born women. Smoking rates among US-born men were higher than earlier published rates among Hispanics and non-Hispanic Whites but similar to rates among African Americans. Current smoking rates among Mexican-born women were lower than published rates for Hispanics, non-Hispanic Whites, and African Americans. Older age, male gender, a higher level of acculturation, more than a high school education, and residing in a census tract with a higher median age predicted history of smoking among US-born participants. Among Mexican-born participants, older age, male gender, a higher level of acculturation, and younger age at migration predicted history of smoking. CONCLUSIONS: Smoking interventions for people of Mexican descent should be tailored according to gender, nativity, and acculturation level and should target all ages, not just young people.