Using motor vehicle crash records for injury surveillance and research in agriculture and forestry.

PROBLEM: Fatal injuries in the agriculture, forestry, and fishing sector (AgFF) outweigh those across all sectors in the United States. Transportation-related injuries are among the top contributors to these fatal events. However, traditional occupational injury surveillance systems may not completely capture crashes involving farm vehicles and logging trucks, specifically nonfatal events. METHODS: The study aimed to develop an integrated database of AgFF-related motor-vehicle crashes for the southwest (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas) and to use these data to conduct surveillance and research. Lessons learned during the pursuit of these aims were cataloged. Activities centered around the conduct of traditional statistical and geospatial analyses of structured data fields and natural language processing of free-text crash narratives. RESULTS: The structured crash data in each state include fields that allowed farm vehicles or equipment and logging trucks to be identified. The variable definitions and coding were not consistent across states but could be harmonized. All states recorded data fields pertaining to person, vehicle, and crash/environmental factors. Structured data supported the construction of crash severity models and geospatial analyses. Law enforcement provided additional details on crash causation in free-text narratives. Crash narratives contained sufficient text to support viable machine learning models for farm vehicle or equipment crashes, but not for logging truck narratives. DISCUSSION: Crash records can help to fill research and surveillance gaps in AgFF in the southwest region. This supports traffic safety's evolution to the current Safe System paradigm. There is a conceptual linkage between the Safe System and Total Worker Health approaches, providing a bridge between traffic safety and occupational health. PRACTICAL APPLICATIONS: Despite limitations, crash records can be an important component of injury surveillance for events involving AgFF vehicles. They also can be used to inform the selection and evaluation of traffic countermeasures and behavioral interventions.

Risk Perceptions in Agricultural Aviation.

BACKGROUND: Agricultural aircraft operations are an integral part of the agricultural sector. According to the National Agriculture Aviation Association (NAAA), aerial applications are conducted in all 50 states of the U.S. and account for 28% of all treated cropland. A typical application operation consists of an operator (Part 137 certificate holder, permission to apply chemicals to agricultural crops) and one or more pilots. This article explores the risk perceptions of operators (pilots with a Part 137 certificate) and non-operators (pilots without a Part 137 certificate) using data from two industry surveys. METHODS: In an effort to explain the differences between risk perceptions of operators and non-operators, a series of regression analyses were conducted controlling for age, work experience, prior encounters with hazards and history of reported injuries. In addition to exploring the aggregated perceptions across all hazards, perceptions of specific hazards were also examined. RESULTS: Data indicate that non-operators perceive hazards as significantly more dangerous than operators. Power lines are perceived as the most hazardous, followed by communication towers and meteorological towers. The regression results indicate that risk perception differences remain even after controlling for differences in age, work experiences, prior hazard encounters and injuries between the two groups. CONCLUSIONS: Heterogeneity in risk perceptions within an organization can result in discrepancies over daily decision-making concerning operations. Further research is needed to identify the causal factors behind the observed differences.

Crash narrative classification: Identifying agricultural crashes using machine learning with curated keywords.

OBJECTIVE: Traditionally, structured or coded data fields from a crash report are the basis for identifying crashes involving different types of vehicles, such as farm equipment. However, using only the structured data can lead to misclassification of vehicle or crash type. The objective of the current article is to examine the use of machine learning methods for identifying agricultural crashes based on the crash narrative and to transfer the application of models to different settings (e.g., future years of data, other states). METHODS: Different data representations (e.g., bag-of-words [BoW], bag-of-keywords [BoK]) and document classification algorithms (e.g., support vector machine [SVM], multinomial naïve Bayes classifier [MNB]) were explored using Texas and Louisiana crash narratives across different time periods. RESULTS: The BoK-support vector classifier (SVC), BoK-MNB, and BoW-SVC models trained with Texas data were better predictive models than the baseline rule-based algorithm on the future year test data, with F1 scores of 0.88, 0.89, 0.85 vs. 0.84. The BoK-MNB trained with Louisiana data performed the closest to the baseline rule-based algorithm on the future year test data (F1 scores, 0.91 baseline rule-based algorithm vs. 0.89 BoK-MNB). The BoK-SVC and BoK-MNB models trained with Texas and Louisiana data were better productive models for Texas future year test data with F1 scores 0.89 and 0.90 vs. 0.84. The BoK-MNB model trained with both states' data was a better predictive model for the Louisiana future year test data, F1 score 0.94 vs. 0.91. CONCLUSIONS: The findings of this study support that machine learning methodologies can potentially reduce the amount of human power required to develop key word lists and manually review narratives.

Evaluating the Impact of Race and Gender on Environmental Risk Perceptions in the Houston Neighborhood of Manchester.

Previous research has shown that white males tend to perceive risks from environmental exposures as lower than women and members of minority populations, often referred to as the white male effect. However, this effect was mostly demonstrated without regard to the actual lived environment experienced by the study participants. There is growing evidence that differences in risk perceptions cannot be adequately explained through race or gender. This cross-sectional study collected survey data from residents of Manchester, a small neighborhood in Houston, Texas, characterized by industrial sites, unimproved infrastructure, nuisance flooding, and poor air quality. Trained community members attempted a complete census within the geographically compact neighborhood. Logistic regression was used to estimate the relative effect of race on environmental health perceptions adjusted for generational age. In contrast to previous research, our study (N = 109) showed that nonwhite individuals perceived a lower environmental health risk compared with their white counterparts. Comparing female and minority racial groups with white males showed that on most issues, white males had the highest perception of risk. For example, adjusted for age, nonwhite respondents perceived the risk of contact with standing water as significantly lower than white respondents (odds ratio = 0.34; 95% confidence interval = 0.12-0.93). This study supports the hypothesis that when environmental conditions experienced by individuals are the same, minority groups tend to underestimate their risk compared with white males. One possible explanation put forth is that communal norms are created within minority populations through generations of exposure to negative environmental conditions compared with white populations.

A semi-automated tool for identifying agricultural roadway crashes in crash narratives.

Objective: Crash reports contain precoded structured data fields and a crash narrative that can be a source of rich information not included in the structured data. The narrative can be useful for identifying vulnerable roadway users, such as agricultural workers. However, using the narratives often requires manual reviews that are time consuming and costly. The objective of this research was to develop a simple and relatively inexpensive, semi-automated tool for screening crash narratives and expediting the process of identifying crashes with specific characteristics, such as agricultural crashes. Methods: Crash records for Louisiana from 2010 to 2015 were obtained from the Louisiana Department of Transportation (LaDOTD). Records with narratives were extracted and stratified by vehicle type. The majority of analyses focused on a vehicle type of farm equipment (Type T). Two keyword lists, an inclusion list and an exclusion list, were created based on the published literature, subject-matter experts, and findings from a pilot project. Next, a semi-automated tool was developed in Microsoft Excel to identify agricultural crashes. Lastly, the tool's performance was assessed using a gold standard set of agricultural narratives identified through manual review. Results: The tool reduced the search space (e.g., number of narratives that need manual review) for narratives requiring manual review from 6.7 to 59.4% depending on the research question. Sensitivity was high, with 96.1% of agricultural crash narratives being correctly classified. Of the gold standard agricultural narratives, 58.3% included an equipment keyword and 72.8% included a farm equipment brand. Conclusion: This article provides information on how crash narratives can supplement structured crash data. It also provides an easy-to-implement method to facilitate incorporating narratives into safety research along with keyword lists for identifying agricultural crashes.

Influence of Work on Elevated Blood Pressure in Hispanic Adolescents in South Texas.

Literature supports an association between work and cardiovascular disease in adults. The objective of this study was to examine the relationship between current work status and elevated blood pressure in Hispanic adolescents. Participants were students in Hidalgo County, located along the Texas-Mexico border. Participants enrolled in the cohort study in ninth grade with assessments completed once a year for up to three years. Participants completed a self-report survey, while staff measured height, weight, waist circumference, blood pressure, and were screened for acanthosis nigricans. A generalized linear regression model with a logit link function was constructed to assess current work status and elevated blood pressure. Of the 508 participants, 29% had elevated blood pressure, which was associated with being male and other chronic disease indicators (e.g., acanthosis nigricans, overweight/obesity). The mean probability for elevated blood pressure was higher among currently working adolescents compared to those who were not. Findings were statistically significant (p < 0.05) at baseline. The findings illustrate that a large proportion of adolescents along the Texas-Mexico border may have elevated blood pressure and that working may be associated with it. Subsequent research is needed to confirm these findings, as well as to identify the mechanism for how work may increase hypertension in adolescents.

Feasibility of Portable Fingerstick Cholinesterase Testing in Adolescents in South Texas.

Adolescents are particularly vulnerable to the impacts of pesticide exposures, which can be assessed using surveys, environmental measurements, and biomonitoring. Biomonitoring of blood cholinesterase can be used to determine if an individual has been exposed to pesticides. A limitation of blood cholinesterase testing can be the use of a laboratory as well as time to receive results. In addition to laboratory tests, there are fingerstick cholinesterase (ChE) tests, which can eliminate the need for laboratory testing. Some populations, such as farmworkers, would benefit through fingerstick ChE tests. The objective of this pilot study is to determine the feasibility (eg, can the testing be used to assess ChE levels) of using fingerstick ChE testing in adolescent populations living along the Texas-Mexico border where adolescents who often engage in farm work live. A sub-objective was to explore differences in ChE levels by sex. The Model 400 Test-Mate ChE kit by EQM Research Inc (Cincinnati, OH) was used to assess for ChE inhibition in the participants, specifically acetylcholinesterase (AChE), which is 1 of the 2 ChE enzymes. During the postassessment, males had a mean AChE value of 3.75 U/mL (95% CI 3.51-3.98); whereas females had a mean AChE value of 2.86 U/mL (95% CI 2.64-3.08), which was statistically significant. Overall, the study supports the use of field ChE testing in adolescent populations with a small percentage (6.90%) refusing to complete ChE testing.

Single Vehicle Logging-Related Traffic Crashes in Louisiana from 2010-2015.

OBJECTIVES: According to the Centers for Disease Control and Prevention (CDC), highway transportation crashes are the number one cause of fatal occupational injuries in the United States. The rate of fatal crashes in logging far exceeds the average annual rate for all sectors combined, yet few studies examine logging-related transportation crashes, and little is known about factors influencing the frequency of these crashes. The purpose of this study was to identify factors associated with fatal and nonfatal injuries among drivers involved in a single vehicle logging-related crash in Louisiana. METHODS: All crashes involving a single logging vehicle from 2010 to 2015 were extracted from a dataset provided by the Louisiana Department of Transportation and Development. Descriptive statistics were computed to characterize crashes by person, vehicle, and environmental factors. A multiple logistic regression model was constructed to identify variables associated with driver injury (fatal and non-fatal). RESULTS: There were 361 crashes involving a single logging vehicle from 2010 to 2015 in Louisiana. Variables associated with driver injury included no seat belt use (OR = 3.23; 95% CI = 1.47-7.10), a violation issued for careless operation of the vehicle (OR = 3.23; 95% CI = 1.40-7.46), a harmful event classified as cargo or equipment loss or shift (OR = 2.47; 95% CI = 1.27-4.82), and a harmful event classified as the vehicle running off the road to the left (OR = 2.29; 95% CI = 1.12-4.70). CONCLUSION: Injury prevention efforts in the logging industry in Louisiana, including commercial vehicle licensing procedures, could benefit from additional driver training to improve crash avoidance skills and careless driving, seat belt use, and methods for securing loads.

Exploring Demographic and Environmental Factors Related to Unintentional Pesticide Poisonings in Children and Adolescents in Texas.

There is limited literature on the frequency and distribution of pesticide exposures, specifically with respect to demographic and environmental factors in the United States. The purpose of this exploratory study was to investigate geographic trends and factors associated with unintentional pesticide exposures in children and adolescents in Texas. The study used an ecological design with secondary data. A spatial scan statistic, based on a Poisson regression model, was employed to identify spatial clusters of unintentional pesticide-related poison center exposures. Next, logistic regression models were constructed to identify potential demographic and environmental factors associated with unintentional pesticide-related poison center exposures. There were 59,477 unintentional pesticide-related poison center exposures from 2000 to 2013. The spatial scan statistic found a change in the number of counties in the identified clusters (e.g. , aggregation of counties with higher than expected exposures) for two time periods (2000-2006; 2007-2013). Based on the logistic regression models, factors associated with unintentional pesticide-related poison center exposures were percent black or African American population, year structure built, and percent moved in the past 12 months. In conclusion, this study found certain demographic and environmental factors may be associated with unintentional pesticide-related poison center exposures. Through understanding trends and associated factors, public health professionals can design interventions for populations at higher risk of pesticide exposures. This study also supports the use of spatial methods being utilized to expand upon current analysis of poison center data. Future research should confirm and build upon these findings.

Bayesian variable selection in the accelerated failure time model with an application to the surveillance, epidemiology, and end results breast cancer data.

Accelerated failure time model is a popular model to analyze censored time-to-event data. Analysis of this model without assuming any parametric distribution for the model error is challenging, and the model complexity is enhanced in the presence of large number of covariates. We developed a nonparametric Bayesian method for regularized estimation of the regression parameters in a flexible accelerated failure time model. The novelties of our method lie in modeling the error distribution of the accelerated failure time nonparametrically, modeling the variance as a function of the mean, and adopting a variable selection technique in modeling the mean. The proposed method allowed for identifying a set of important regression parameters, estimating survival probabilities, and constructing credible intervals of the survival probabilities. We evaluated operating characteristics of the proposed method via simulation studies. Finally, we apply our new comprehensive method to analyze the motivating breast cancer data from the Surveillance, Epidemiology, and End Results Program, and estimate the five-year survival probabilities for women included in the Surveillance, Epidemiology, and End Results database who were diagnosed with breast cancer between 1990 and 2000.

Characteristics of acute occupational pesticide exposures reported to poison control centers in Texas, 2000-2015.

In the United States, there is limited literature on occupational pesticide exposures despite being associated with adverse health outcomes, including in large states such as Texas. The purpose of this article is to characterize occupational pesticide poison center exposures in Texas. Descriptive statistics were used to describe exposures (eg, exposure routes, type of pesticide, medical outcome, clinical effects, and temporal/seasonal patterns). From 2000 to 2015, there were 2,303 occupational pesticide poison center exposures. Common types of reported pesticides were insecticides (67.3%), herbicides (17.7%), and repellents (5.8%). The highest proportion of exposures were among those aged 20 to 29 years (24.9%). The top clinical effect categories were gastrointestinal (25.8%), neurological (19.2%), and dermal (14.9%). Characterizing occupational pesticide poison center exposures can support improved surveillance systems and guide future research or interventions.

The Impacts of Exposure to Environmental Risk on Physical and Mental Health in a Small Geographic Community in Houston, TX.

Previous research has shown that communities with low average socioeconomic status (SES) and majority minority populations are more likely to be exposed to industrial buildings, waste facilities, and poor infrastructure compared to white communities with higher average SES. While some studies have demonstrated linkages between exposures to specific environmental contaminates within these communities and negative health outcomes, little research has analyzed the effects of environmental contaminants on the mental and physical health of these populations. A cross-sectional survey collected data from residents of Manchester, a small neighborhood in Houston, TX, that is characterized by industrial sites, unimproved infrastructure, nuisance flooding, and poor air quality. Our study (N = 109) utilized the 12 item Short Form Health Survey version 2 (SF12v2) to assess the general mental and physical health of the community. The community as a whole had reduced physical health scores compared to U.S. national averages. The time residents had lived in the neighborhood was also correlated with a reported reduction in physical health scores (r2 = 0.136; p-value <0.001). The association between time lived in the neighborhood and poorer health scores remained after adjusting for age, race, and gender (coef = -0.27, p-value <0.001). Mental health scores were within national averages and time spent living in the neighborhood did not appear to negatively impact respondent's mental health scores. These findings point to the need for more research to determine the potential for additive physical and mental health impacts in long-term residents in neighborhoods characterized by environmental justice issues.

"The Only Thing I Wish I Could Change Is That They Treat Us Like People and Not Like Animals": Injury and Discrimination Among Latino Farmworkers.

OBJECTIVE: This article describes how perceived discrimination shapes the way Latino farmworkers encounter injuries and seek out treatment. METHODS: After 5 months of ethnographic fieldwork, 89 open-ended, semistructured interviews were analyzed. NVivo was used to code and qualitatively organize the interviews and field notes. Finally, codes, notes, and co-occurring dynamics were used to iteratively assess the data for major themes. RESULTS: The primary source of perceived discrimination was the "boss" or farm owner. Immigrant status was also a significant influence on how farmworkers perceived the discrimination. Specifically, the ability to speak English and length of stay in the United States were related to stronger perceptions of discrimination. Finally, farm owners compelled their Latino employees to work through their injuries without treatment. CONCLUSIONS: This ethnographic account brings attention to how discrimination and lack of worksite protections are implicated in farmworkers' injury experiences and suggests the need for policies that better safeguard vulnerable workers.

Confirming the Environmental Concerns of Community Members Utilizing Participatory-Based Research in the Houston Neighborhood of Manchester.

In the last few decades, there has been an increase in community-based participatory research being conducted within the United States. Recent research has demonstrated that working with local community organizations, interest groups, and individuals can assist in the creation of, and sustainability in, health initiatives, adoption of emergency protocols, and potentially improve health outcomes for at-risk populations. However little research has assessed if communal concerns over environmental contaminants would be confirmed through environmental research. This cross-sectional study collected survey data and performed surface water analysis for heavy metals in a small neighborhood in Houston, TX, which is characterized by industrial sites, unimproved infrastructure, nuisance flooding, and poor air quality. Surveys were completed with 109 residents of the Manchester neighborhood. Water samples were taken from thirty zones within the neighborhood and assessed for arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), lead (Pb), selenium (Se), silver (Ag), and mercury (Hg). Survey results showed that the vast majority of all respondents were concerned over proximity to industry and waste facilities, as well as exposure to standing surface water. Barium was discovered in every sample and many of the zones showed alarming levels of certain metals. For example, one zone, two blocks from a public park, showed levels of arsenic at 180 (µg/L), barium at 3296 (µg/L), chromium at 363 (µg/L), lead at 1448 (µg/L), and mercury at 10 (µg/L). These findings support the hypothesis that neighborhood members are aware of the issues affecting their community and can offer researchers valuable assistance in every stage of study design and execution.

Pesticide-Related Hospitalizations Among Children and Teenagers in Texas, 2004-2013.

OBJECTIVE: Acute exposure to pesticides is associated with nausea, headaches, rashes, eye irritation, seizures, and, in severe cases, death. We characterized pesticide-related hospitalizations in Texas among children and teenagers for 2004-2013 to characterize exposures in this population, which is less well understood than pesticide exposure among adults. METHODS: We abstracted information on pesticide-related hospitalizations from hospitalization data using pesticide-related International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes and E-codes. We calculated the prevalence of pesticide-related hospitalizations among children and teenagers aged #19 years for all hospitalizations, unintentional exposures, intentional exposures, pesticide classifications, and illness severity. We also calculated age- and sex-specific prevalence of pesticide-related hospitalizations among children. RESULTS: The prevalence of pesticide-related hospitalizations among children and teenagers was 2.1 per 100,000 population. The prevalence of pesticide-related hospitalizations per 100,000 population was 2.7 for boys and 1.5 for girls. The age-specific prevalence per 100,000 population was 5.3 for children aged 0-4 years, 0.3 for children and teenagers aged 5-14 years, and 2.3 for teenagers aged 15-19 years. Children aged 0-4 years had the highest prevalence of unintentional exposures, whereas teenagers aged 15-19 years had the highest prevalence of intentional exposures. Commonly reported pesticide categories were organophosphates/carbamates, disinfectants, rodenticides, and other pesticides (e.g., pyrethrins, pyrethroids). Of the 158 pesticide-related hospitalizations, most were coded as having minor (n=86) or moderate (n=40) illness severity. CONCLUSION: Characterizing the prevalence of pesticide-related hospitalizations among children and teenagers leads to a better understanding of the burden of pesticide exposures, including the type of pesticides used and the severity of potential health effects. This study found differences in the frequency of pesticide-related hospitalizations by sex, age, and intent (e.g., unintentional vs. intentional).

Pesticide-related poison center exposures in children and adolescents aged ≤19 years in Texas, 2000-2013.

CONTEXT: Although national poison center data show that pesticides were the 8th most commonly reported substance category (3.27%) for children aged ≤5 years in 2014, there is limited information on childhood and adolescent pesticide exposures. OBJECTIVE: This study assessed pesticide-related poison center exposures in children and adolescents aged ≤19 years from 2000-2013 in Texas to characterize the potential burden of pesticides. MATERIALS AND METHODS: Pesticide-related poison center exposures among children and adolescents aged ≤19 years reported to Texas poison centers were identified. The distribution of exposures was estimated by gender, age category, medical outcome, management site, exposure route, and pesticide category. RESULTS: From 2000 to 2013, there were 61,147 pesticide-related poison center exposures in children and adolescents aged ≤19 years. The prevalence was highest among males at 864.24 per 100,000 population. The prevalence of unintentional exposures was highest among children aged ≤5 years at 2310.69 per 100,000 population, whereas the prevalence of intentional exposures was highest among adolescents aged 13-19 years at 13.82 per 100,000 population. A majority of medical outcomes reported were classified as having no effect (30.24%) and not followed, but minimal clinical effects possible (42.74%). Of all the exposures, 81.24% were managed on site. However, 57% of intentional exposures were referred to or treated at a health-care facility. The most common routes of exposure were ingestion (80.83%) and dermal (17.21%). The most common pesticide categories included rodenticides (30.02%), pyrethrins/pyrethroids (20.69%), and other and unspecified insecticides (18.14%). DISCUSSION: The study found differences in the frequency of exposures by intent for sex and age categories, and identified the most common medical outcomes, management site, exposure route, and pesticide category. CONCLUSION: Through characterizing pesticide-related poison center exposures, future interventions can be designed to address groups with higher prevalence of exposure.

Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health.

OBJECTIVE: To honor Tom Waters's work on emerging occupational health issues, we review the literature on physical along with chemical exposures and their impact on functional outcomes. BACKGROUND: Many occupations present the opportunity for exposure to multiple hazardous exposures, including both physical and chemical factors. However, little is known about how these different factors affect functional ability and injury. The goal of this review is to examine the relationships between these exposures, impairment of the neuromuscular and musculoskeletal systems, functional outcomes, and health problems with a focus on acute injury. METHOD: Literature was identified using online databases, including PubMed, Ovid Medline, and Google Scholar. References from included articles were searched for additional relevant articles. RESULTS: This review documented the limited existing literature that discussed cognitive impairment and functional disorders via neurotoxicity for physical exposures (heat and repetitive loading) and chemical exposures (pesticides, volatile organic compounds [VOCs], and heavy metals). CONCLUSION: This review supports that workers are exposed to physical and chemical exposures that are associated with negative health effects, including functional impairment and injury. Innovation in exposure assessment with respect to quantifying the joint exposure to these different exposures is especially needed for developing risk assessment models and, ultimately, preventive measures. APPLICATION: Along with physical exposures, chemical exposures need to be considered, alone and in combination, in assessing functional ability and occupationally related injuries.

Predicting violent behavior in clinical settings: a case-control study of a mental health inpatient unit.

In order to assist staff in recognizing patients prone to violence and guide their clinical decision-making, this study summarizes mental health inpatient unit incidents over a one-year period. Results describe demographic and clinical information for patients, and evaluate risk assessment tools currently used to predict risk. A retrospective analysis included data on patients involved in incidents and frequency matched controls. There were a total of 44 incidents, caused by 38 unique patients. A constructed model to estimate patient characteristics and risk of violent incidents included involuntary admittance (OR 2.07, 95% CI 1.05-6.11, p = 0.039), more than one admission at the facility (OR 4.18, 95% CI 1.71-10.22, p = 0.002) and Global Subjective Irritability on day one (OR 4.24, 95% CI 1.77-10.16, p = 0.001). Violent incidents on the mental inpatient unit threaten safety and disrupt the therapeutic environment. The findings may be useful in aiding clinicians to quickly recognize patients that are prone to violence.

Prenatal Exposure to Nitrosatable Drugs, Dietary Intake of Nitrites, and Preterm Birth.

Prenatal exposure to nitrosatable drugs, including secondary or tertiary amines, has been associated with preterm birth. Associations may be accentuated by higher intakes of dietary nitrites because of the increased formation of N-nitroso compounds. Using data from mothers of babies without major birth defects (controls) from the National Birth Defects Prevention Study, we examined the relationship between nitrosatable drug exposure in conjunction with dietary nitrite intake and preterm birth among 496 mothers of preterm infants and 5,398 mothers with full-term deliveries in 1997-2005. A protective association was observed with a high intake of plant nitrites (adjusted hazard ratio (AHR) = 0.72, 95% confidence interval (CI): 0.53, 0.97). Secondary amines in conjunction with high nitrite intake were associated with preterm birth during the first (AHR = 1.84, 95% CI: 1.14, 2.98), second (AHR = 1.89, 95% CI: 1.17, 3.07), and third (AHR = 2.00, 95% CI: 1.22, 3.29) trimesters. The adjusted hazard ratios for tertiary amine use in the third trimester by increasing tertiles of nitrite intake were 0.67 (95% CI: 0.35, 1.31), 1.25 (95% CI: 0.71, 2.19), and 2.02 (95% CI: 1.17, 3.49). Prenatal exposure to nitrosatable drugs, particularly secondary and tertiary amines, in conjunction with higher levels of dietary nitrite intake may increase the risk of preterm birth.

Cardiovascular Disease Risk Factors in Hispanic Adolescents in South Texas.

OBJECTIVES: Despite a national crisis of increased prevalence of obesity and type 2 diabetes mellitus in adolescents, especially among Hispanics, there is a paucity of data on health indicators among farmworker adolescents and their peers. The main aim of this study was to estimate the prevalence of cardiovascular disease risk factors in a population of Hispanic adolescent students in south Texas. The study also aimed to compare the prevalence of these risk factors between students enrolled in the Migrant Education Program (MEP) and other students, and between boys and girls. METHODS: In partnership with the Weslaco (Texas) Independent School District and the Migrant Education Department, a cohort study was conducted from 2007 to 2010 to estimate the prevalence of overall obesity (body mass index ≥85th percentile for age and sex), abdominal obesity (waist circumference ≥75th percentile for age, sex, and ethnicity), acanthosis nigricans (AN), and high blood pressure (HBP; ≥90th percentile for age, height, and sex or systolic/diastolic BP ≥120/80 mm Hg) among MEP students compared with other students from two south Texas high schools. Multilevel logistic regression was used to assess the relation between sex and our main outcomes of interest while accounting for within-school nesting of participants. RESULTS: Among 628 sampled students, 508 (80.9%) completed the consent procedure and participated in the study. Of these, 257 were MEP students and 251 were non-MEP peers. Approximately 96.7% of participants were Hispanic and 50.0% were boys. Analyses of data across the years comparing MEP students and non-MEP students show an average prevalence of 44.8% versus 47.7% for overall obesity, 43.2% versus 43.7% for abdominal obesity, 24.7% versus 24.7% for AN, and 29.2% versus 32.8% for HBP. Across recruitment and follow-up years, the prevalence of overall obesity, abdominal obesity, and HBP was 1.3 to 1.5, 1.2 to 1.8, and 2.9 to 4.6 times higher in boys than in girls, respectively. In contrast, the prevalence of AN varied little by sex. CONCLUSIONS: The high prevalence of cardiovascular risk factors in both groups suggests a compelling need for comprehensive, culturally targeted interventions to prevent future cardiovascular diseases in these high-risk Hispanic adolescents, especially among boys. There were not, however, substantial differences between MEP students and other students. These findings also support the feasibility of conducting future epidemiologic studies among adolescent farmworkers and their families, as well as culturally appropriate school or community-based interventions.