Costs and Projected Effect of a Federally Qualified Health Center-Based Mailed Colorectal Cancer Screening Program in Texas.

Introduction: Mailed stool testing for colorectal cancer (CRC) may improve screening uptake and reduce the incidence and mortality of CRC, especially among patients at federally qualified health centers (FQHCs). To expand screening programs it is important to identify cost-effective approaches. Methods: We developed a decision-analytic model to estimate the cost, effects on screening and patient outcomes (CRCs detected, CRCs prevented, CRC deaths prevented), and cost-effectiveness of implementing a state-wide mailed stool testing program over 5 years among unscreened, age-eligible (aged 50-75 y) patients at FQHCs in Texas. We compared various outreach strategies and organizational structures (centralized, regional, or a hybrid). We used data from our existing regional mailed stool testing program and recent systematic reviews to set parameters for the model. Costs included start-up and ongoing activities and were estimated in 2022 US dollars from the perspective of a hypothetical third-party payer. Cost-effectiveness was assessed by using both incremental and average cost-effectiveness ratios. Results: Using either a statewide centralized or hybrid organizational configuration to mail stool tests to newly eligible FQHC patients and patients who have responded at least once since program inception is likely to result in the best use of resources over 5 years, enabling more than 110,000 additional screens, detecting an incremental 181 to 194 CRCs, preventing 91 to 98 CRCs, and averting 46 to 50 CRC deaths, at a cost of $10 million to $11 million compared with no program. Conclusions: A statewide mailed stool testing program for FQHC patients can be implemented at reasonable cost with considerable effects on CRC screening outcomes, especially when its structure maximizes program efficiency while maintaining effectiveness.

High polygenic risk score is a risk factor associated with colorectal cancer based on data from the UK Biobank.

Colorectal cancer (CRC) is a common cancer among both men and women and is one of the leading causes of cancer death worldwide. It is important to identify risk factors that may be used to help reduce morbidity and mortality of the disease. We used a case-control study design to explore the association between CRC, polygenic risk scores (PRS), and other factors. We extracted data about 2,585 CRC cases and 9,362 controls from the UK Biobank, calculated the PRS for these cases and controls based on 140 single nucleotide polymorphisms, and performed logistic regression analyses for the 11,947 cases and controls, for an older group (ages 50+), and for a younger group (younger than 50). Five significant risk factors were identified when all 11,947 cases and controls were considered. These factors were, in descending order of the values of the adjusted odds ratios (aOR), high PRS (aOR: 2.70, CI: 2.27-3.19), male sex (aOR: 1.52, CI: 1.39-1.66), unemployment (aOR: 1.47, CI: 1.17-1.85), family history of CRC (aOR: 1.44, CI: 1.28-1.62), and age (aOR: 1.01, CI: 1.01-1.02). These five risk factors also remained significant in the older group. For the younger group, only high PRS (aOR: 2.87, CI: 1.65-5.00) and family history of CRC (aOR: 1.73, CI: 1.12-2.67) were significant risk factors. These findings indicate that genetic risk for the disease is a significant risk factor for CRC even after adjusting for family history. Additional studies are needed to examine this association using larger samples and different population groups.

Industrial air pollution and low birth weight in New Mexico, USA.

In recent decades, the low birth weight (LBW) rate in New Mexico has consistently exceeded the Unites States average. Maternal exposure to air pollution during pregnancy may be a significant contributor to LBW in offspring. This study investigated the links between maternal residential exposure to air pollution from industrial sources and the risk of LBW in offspring. The analysis included 22,375 LBW cases and 233,340 controls. It focused on 14 common chemicals listed in the Toxic Release Inventory (TRI) and monitoring datasets, which have abundant monitoring samples. The Emission Weighted Proximity Model (EWPM) was used to calculate maternal air pollution exposure intensity. Adjusted odds ratios (adjORs) were calculated using binary logistic regressions to examine the association between maternal residential air pollution exposure and LBW, while controlling for potential confounders, such as the maternal age, race/ethnicity, gestational age, prenatal care, education level, consumption of alcohol during pregnancy, public health regions, child's sex, and the year of birth. Multiple comparison correction was applied using the False Discovery Rate approach. The results showed that maternal residential exposure to 1,2,4-trimethylbenzene, benzene, chlorine, ethylbenzene, and styrene had significant positive associations with LBW in offspring, with adjusted odds ratios ranging from 1.10 to 1.13. These five chemicals remained as significant risk factors after dividing the estimated exposure intensities into four categories. In addition, significant linear trends were found between LBW and maternal exposure to each of the five identified chemicals. Furthermore, 1,2,4-trimethylbenzene was identified as a risk factor to LBW for the first time. The findings of this study should be confirmed through additional epidemiological, biological, and toxicological studies.

Determining Association between Lung Cancer Mortality Worldwide and Risk Factors Using Fuzzy Inference Modeling and Random Forest Modeling.

Lung cancer remains the leading cause for cancer mortality worldwide. While it is well-known that smoking is an avoidable high-risk factor for lung cancer, it is necessary to identify the extent to which other modified risk factors might further affect the cell's genetic predisposition for lung cancer susceptibility, and the spreading of carcinogens in various geographical zones. This study aims to examine the association between lung cancer mortality (LCM) and major risk factors. We used Fuzzy Inference Modeling (FIM) and Random Forest Modeling (RFM) approaches to analyze LCM and its possible links to 30 risk factors in 100 countries over the period from 2006 to 2016. Analysis results suggest that in addition to smoking, low physical activity, child wasting, low birth weight due to short gestation, iron deficiency, diet low in nuts and seeds, vitamin A deficiency, low bone mineral density, air pollution, and a diet high in sodium are potential risk factors associated with LCM. This study demonstrates the usefulness of two approaches for multi-factor analysis of determining risk factors associated with cancer mortality.

Spatial Insights for Understanding Colorectal Cancer Screening in Disproportionately Affected Populations, Central Texas, 2019.

INTRODUCTION: Colorectal cancer (CRC) screening can reduce morbidity and mortality; however, important disparities exist in CRC uptake. Our study examines the associations of distance to care and frequency of using primary care and screening. METHODS: To examine the distribution of screening geographically and according to several demographic features, we used individual patient-level data, dated September 30, 2018, from a large urban safety-net health system in Central Texas. We used spatial cluster analysis and logistic regression adjusted for age, race, sex, socioeconomic status, and health insurance status. RESULTS: We obtained screening status data for 13,079 age-eligible patients from the health system's electronic medical records. Of those eligible, 55.1% were female, and 55.9% identified as Hispanic. Mean age was 58.1 years. Patients residing more than 20 miles from one of the system's primary care clinics was associated with lower screening rates (odds ratio [OR], 0.63; 95% CI, 0.43-0.93). Patients with higher screening rates included those who had a greater number of primary care-related (nonspecialty) visits within 1 year (OR, 6.90; 95% CI, 6.04-7.88) and those who were part of the county-level medical assistance program (OR, 1.61; 95% CI, 1.40-1.84). Spatial analysis identified an area where the level of CRC screening was particularly low. CONCLUSION: Distance to primary care and use of primary care were associated with screening. Priorities in targeted interventions should include identifying and inviting patients with limited care engagements.

Geographic Variations of Racial/Ethnic Disparities in Late-Stage Diagnosis of Childhood Cancer in Texas.

OBJECTIVES: This study aimed to identify small geographic areas where the childhood cancer yearly incidence and late-stage diagnosis rates were disproportionately higher among racial/ethnic minorities (Hispanics and non-Hispanic African Americans) in Texas. METHODS: The study examined childhood cancer disparities in Texas from 2005 to 2014, based on geographic location and race/ethnicity. Relative (risk ratio) and absolute (risk difference) measures were used to investigate racial disparities of childhood cancer late-stage diagnosis in small geographic areas (census tracts). The study investigated childhood cancer yearly incidence- and late-stage diagnosis rates for three racial groups combined. The study also analyzed the temporal change of childhood cancer late-stage diagnosis rates based on the data from census tracts where disparities existed for Hispanics and non-Hispanic African Americans compared with a non-Hispanic white reference group. RESULTS: A total of 54% of the cases in the study cohort were diagnosed in the late stage. Although there were fewer non-Hispanic African Americans cases compared with non-Hispanic white and Hispanic cases, they showed significant geographic variation in racial/ethnic disparities compared with the non-Hispanic white reference group. The study also revealed that 58 census tracts for non-Hispanic African Americans and 47 census tracts for Hispanics (of 5265) had significantly higher late-stage diagnosis rates compared with non-Hispanic whites. The findings also demonstrated consistent increases in incidence and late-stage diagnosis from 2005 to 2014 for all cases combined. CONCLUSIONS: Most of the significant census tracts with a higher late-stage diagnosis rate for Hispanics were located on the outskirts of the Dallas-Fort Worth, Houston, and San Antonio areas. In contrast, geographic disparities of childhood cancer late-stage diagnosis for non-Hispanic African Americans were found inside the large metropolitan areas of Houston and Dallas-Fort Worth. The findings of this study will help prioritize the geographical allocation of resources, which, in turn, will help to facilitate preventive healthcare services and alleviate the disease burden in children.

Geospatial-Temporal and Demand Models for Opioid Admissions, Implications for Policy.

Background: As the opioid epidemic continues, understanding the geospatial, temporal, and demand patterns is important for policymakers to assign resources and interdict individual, organization, and country-level bad actors. Methods: GIS geospatial-temporal analysis and extreme-gradient boosted random forests evaluate ICD-10 F11 opioid-related admissions and admission rates using geospatial analysis, demand analysis, and explanatory models, respectively. The period of analysis was January 2016 through September 2018. Results: The analysis shows existing high opioid admissions in Chicago and New Jersey with emerging areas in Atlanta, Salt Lake City, Phoenix, and Las Vegas. High rates of admission (claims per 10,000 population) exist in the Appalachian area and on the Northeastern seaboard. Explanatory models suggest that hospital overall workload and financial variables might be used for allocating opioid-related treatment funds effectively. Gradient-boosted random forest models accounted for 87.8% of the variability of claims on blinded 20% test data. Conclusions: Based on the GIS analysis, opioid admissions appear to have spread geographically, while higher frequency rates are still found in some regions. Interdiction efforts require demand-analysis such as that provided in this study to allocate scarce resources for supply-side and demand-side interdiction: Prevention, treatment, and enforcement.

Industrial air pollution and low birth weight: a case-control study in Texas, USA.

Many studies have investigated associations between maternal residential exposures to air pollutants and low birth weight (LBW) in offspring. However, most studies focused on the criteria air pollutants (PM2.5, PM10, O3, NO2, SO2, CO, and Pb), and only a few studies examined the potential impact of other air pollutants on LBW. This study investigated associations between maternal residential exposure to industrial air emissions of 449 toxics release inventory (TRI) chemicals and LBW in offspring using a case-control study design based on a large dataset consisting of 94,106 LBW cases and 376,424 controls in Texas from 1996 to 2008. Maternal residential exposure to chemicals was estimated using a modified version of the emission-weighted proximity model (EWPM). The model takes into account reported quantities of annual air emission from industrial facilities and the distances between the locations of industrial facilities and maternal residence locations. Binary logistic regression was used to compute odds ratios measuring the association between maternal exposure to different TRI chemicals and LBW in offspring. Odds ratios were adjusted for child's sex, birth year, gestational length, maternal age, education, race/ethnicity, and public health region of maternal residence. Among the ten chemicals selected for a complete analysis, maternal residential exposures to five TRI chemicals were positively associated with LBW in offspring. These five chemicals include acetamide (adjusted odds ratio [aOR] 2.29, 95% confidence interval [CI] 1.24, 4.20), p-phenylenediamine (aOR 1.63, 95% CI 1.18, 2.25), 2,2-dichloro-1,1,1-trifluoroethane (aOR 1.41, 95% CI 1.20, 1.66), tributyltin methacrylate (aOR 1.20, 95% CI 1.06, 1.36), and 1,1,1-trichloroethane (aOR 1.11, 95% CI 1.03, 1.20). These findings suggest that maternal residential proximity to industrial air emissions of some chemicals during pregnancy may be associated with LBW in offspring.

Associations between maternal residential proximity to air emissions from industrial facilities and low birth weight in Texas, USA.

BACKGROUND: Most previous studies examining associations between maternal exposures to air pollutants during pregnancy and low birth weight (LBW) in offspring focused on criteria air pollutants (PM2.5, PM10, O3, NO2, SO2, CO, and Pb). The relationship between non-criteria air pollutants and LBW is understudied and requires greater coverage. OBJECTIVES: This study investigated associations between maternal residential exposure to industrial air pollutants during pregnancy and LBW in offspring. METHODS: This study used a case-control study design that included 94,106 term LBW cases and 376,424 controls. It covered 78 air pollutants common to both the Toxics Release Inventory (TRI) and ground air quality monitoring databases in Texas during 1996-2008. A modified version of the Emission Weighted Proximity Model (EWPM), calibrated with ground monitoring data, was used to estimate maternal residential exposure to industrial air pollutants during pregnancy. Binary logistic regression analyses were performed to calculate odds ratios (ORs) reflecting the associations of maternal exposure to industrial air pollutants and LBW in offspring, adjusted for child's sex, gestational weeks, maternal age, education, race/ethnicity, marital status, prenatal care, tobacco use during pregnancy, public health region of maternal residence, and year of birth. In addition, the Bonferroni correction for multiple comparisons was applied to the results of logistic regression analysis. RESULTS: Relative to the non-exposed reference group, maternal residential exposure to benzene (adjusted odds ratio (aOR) 1.06, 95% confidence interval (CI) 1.04, 1.08), benzo(g,h,i)perylene (aOR 1.04, 95% CI 1.02, 1.07), cumene (aOR 1.05, 95% CI 1.03, 1.07), cyclohexane (aOR 1.04, 95% CI 1.02, 1.07), dichloromethane (aOR 1.04, 95% CI 1.03, 1.07), ethylbenzene (aOR 1.05, 95% CI 1.03, 1.06), ethylene (aOR 1.06, 95% CI 1.03, 1.09), mercury (aOR 1.04, 95% CI 1.02, 1.07), naphthalene (aOR 1.03, 95% CI 1.01, 1.05), n-hexane (aOR 1.06, 95% CI 1.04, 1.08), propylene (aOR 1.06, 95% CI 1.03, 1.10), styrene (aOR 1.06, 95% CI 1.04, 1.08), toluene (aOR 1.05, 95% CI 1.03, 1.07), and zinc (fume or dust) (aOR 1.10, 95% CI 1.06, 1.13) was found to have significantly higher odds of LBW in offspring. When the estimated exposures were categorized into four different groups (zero, low, medium, and high) in the analysis, eleven of the fourteen air pollutants, with the exception of benzo(g,h,i)perylene, ethylene, and propylene, remained as significant risk factors. CONCLUSIONS: Results indicate that maternal residential proximity to industrial facilities emitting any of the fourteen pollutants identified by this study during pregnancy may be associated with LBW in offspring. With the exception of benzene, ethylbenzene, toluene, and zinc, the rest of the fourteen air pollutants are identified as LBW risk factors for the first time by this study. Further epidemiological, biological, and toxicological studies are suggested to verify the findings from this study.

Validity of the Emission Weighted Proximity Model in estimating air pollution exposure intensities in large geographic areas.

BACKGROUND: Accurate estimates of air pollution exposure intensities are important to support environmental epidemiology analyses that require data covering large geographic areas over multiple years. The Emission Weighted Proximity Model (EWPM) and the National-Scale Air Toxics Assessment (NATA) are two viable approaches for obtaining estimate exposure intensities. The advantages of the EWPM include its simplicity and significantly lower costs of implementation. However, very limited data are available regarding the validity of the results from the EWPM and how these results would fare when compared with those from the NATA. METHODS: This study evaluates the validity of the estimated exposure intensities from the EWPM through a correlation analysis with ground monitoring data obtained by the Texas Commission on Environmental Quality (TCEQ). The monitoring data used in the comparison included 27 non-criteria air pollutants at 48 monitoring sites in Texas in 2005. In addition, this study compares the results from the EWPM with those from NATA using the TCEQ data as a gold standard. RESULTS: Analysis results suggest that estimated exposure intensities from the EWPM and the NATA were comparable when the intensities from both approaches are used to categorize environmental exposure intensities into different levels in relative terms. CONCLUSION: These findings suggest that the EWPM is a valid alternative approach to the NATA in situations where epidemiological analysis requires both environmental data and health outcome data that cover a large geographic area over multiple years.

Influencing factor analysis of phosphorus loads from non-point source: a case study in central China.

The influence factor analysis for non-point source (NPS) pollution is very important to taking effective water pollution control measures. In this study, the self-organizing map (SOM) and linear model analysis were used to analyze the relationships between total phosphorus (TP) loads and influencing factors, both qualitatively and quantitatively. The land-use type, topography, and vegetation coverage were the main factors influencing the export of TP loads in Tangxun watershed. Slope and normalized difference vegetation index (NDVI) were chosen as characteristic indices of topography and vegetation coverage, respectively. For the whole watershed, the high TP loads were mainly distributed in areas with high slope and low vegetation coverage for a specific land-use type. For different land types, the slope significantly influenced the export of TP loads in waste/bare land and forest/green land while NDVI influenced the export of TP loads in forest/green land and farmland. In terms of multi-factor analysis, the comprehensive influence of slope and NDVI on TP loads showed as waste/bare land>forest/green land>farmland>rural/urban construction land.

Maternal residential proximity to chlorinated solvent emissions and birth defects in offspring: a case-control study.

BACKGROUND: Some studies have noted an association between maternal occupational exposures to chlorinated solvents and birth defects in offspring, but data are lacking on the potential impact of industrial air emissions of these solvents on birth defects. METHODS: With data from the Texas Birth Defects Registry for births occurring in 1996-2008, we examined the relation between maternal residential proximity to industrial air releases of chlorinated solvents and birth defects in offspring of 60,613 case-mothers and 244,927 control-mothers. Maternal residential exposures to solvent emissions were estimated with metrics that took into account residential distances to industrial sources and annual amounts of chemicals released. Logistic regression was used to generate odds ratios and 95% confidence intervals for the associations between residential proximity to emissions of 14 chlorinated solvents and selected birth defects, including neural tube, oral cleft, limb deficiency, and congenital heart defects. All risk estimates were adjusted for year of delivery and maternal age, education, race/ethnicity, and public health region of residence. RESULTS: Relative to exposure risk values of 0, neural tube defects were associated with maternal residential exposures (exposure risk values >0) to several types of chlorinated solvents, most notably carbon tetrachloride (adjusted odds ratio [aOR] 1.42, 95% confidence interval [CI] 1.09, 1.86); chloroform (aOR 1.40, 95% CI 1.04, 1.87); ethyl chloride (aOR 1.39, 95% CI 1.08, 1.79); 1,1,2-trichloroethane (aOR 1.56, 95% CI 1.11, 2.18); and 1,2,3-trichloropropane (aOR 1.49, 95% CI 1.08, 2.06). Significant associations were also noted between a few chlorinated solvents and oral cleft, limb deficiency, and congenital heart defects. We observed stronger associations between some emissions and neural tube, oral cleft, and heart defects in offspring of mothers 35 years or older, such as spina bifida with carbon tetrachloride (aOR 2.49, 95% CI 1.09, 5.72), cleft palate with 1,2-dichloroethane (aOR 1.93, 95% 1.05, 3.54), cleft lip with or without cleft palate with ethyl chloride (aOR 1.81, 95% CI 1.06, 3.07), and obstructive heart defects with trichloroethylene (aOR 1.43, 95% CI 1.08, 1.88). CONCLUSIONS: These findings suggest that maternal residential proximity to industrial emissions of chlorinated solvents might be associated with selected birth defects in offspring, especially among older mothers.

Racial/Ethnic, socioeconomic, and geographic disparities of cervical cancer advanced-stage diagnosis in Texas.

BACKGROUND: Advanced-stage diagnosis is among the primary causes of mortality among cervical cancer patients. With the wide use of Pap smear screening, cervical cancer advanced-stage diagnosis rates have decreased. However, disparities of advanced-stage diagnosis persist among different population groups. A challenging task in cervical cancer disparity reduction is to identify where underserved population groups are. METHODS: Based on cervical cancer incidence data between 1995 and 2008, this study investigated advanced-stage cervical cancer disparities in Texas from three social domains: Race/ethnicity, socioeconomic status (SES), and geographic location. Effects of individual and contextual factors, including age, tumor grade, race/ethnicity, as well as contextual SES, spatial access to health care, sociocultural factors, percentage of African Americans, and insurance expenditures, on these disparities were examined using multilevel logistic regressions. FINDINGS: Significant variations by race/ethnicity and SES were found in cervical cancer advanced-stage diagnosis. We also found a decline in racial/ethnic disparities of advanced cervical cancer diagnosis rate from 1995 to 2008. However, the progress was slower among African Americans than Hispanics. Geographic disparities could be explained by age, race/ethnicity, SES, and the percentage of African Americans in a census tract. CONCLUSIONS: Our findings have important implications for developing effective cervical cancer screening and control programs. We identified the location of underserved populations who need the most assistance with cervical cancer screening. Cervical cancer intervention programs should target Hispanics and African Americans, as well as individuals from communities with lower SES in geographic areas where higher advanced-stage diagnosis rates were identified in this study.

Modeling urban growth by the use of a multiobjective optimization approach: environmental and economic issues for the Yangtze watershed, China.

Urban growth is an unavoidable process caused by economic development and population growth. Traditional urban growth models represent the future urban growth pattern by repeating the historical urban growth regulations, which can lead to a lot of environmental problems. The Yangtze watershed is the largest and the most prosperous economic area in China, and it has been suffering from rapid urban growth from the 1970s. With the built-up area increasing from 23,238 to 31,054 km(2) during the period from 1980 to 2005, the watershed has suffered from serious nonpoint source (NPS) pollution problems, which have been mainly caused by the rapid urban growth. To protect the environment and at the same time maintain the economic development, a multiobjective optimization (MOP) is proposed to tradeoff the multiple objectives during the urban growth process of the Yangtze watershed. In particular, the four objectives of minimization of NPS pollution, maximization of GDP value, minimization of the spatial incompatibility between the land uses, and minimization of the cost of land-use change are considered by the MOP approach. Conventionally, a genetic algorithm (GA) is employed to search the Pareto solution set. In our MOP approach, a two-dimensional GA, rather than the traditional one-dimensional GA, is employed to assist with the search for the spatial optimization solution, where the land-use cells in the two-dimensional space act as genes in the GA. Furthermore, to confirm the superiority of the MOP approach over the traditional prediction approaches, a widely used urban growth prediction model, cellular automata (CA), is also carried out to allow a comparison with the Pareto solution of MOP. The results indicate that the MOP approach can make a tradeoff between the multiple objectives and can achieve an optimal urban growth pattern for Yangtze watershed, while the CA prediction model just represents the historical urban growth pattern as the future growth pattern. Moreover, according to the spatial clustering index, the urban growth pattern predicted through MOP is more reasonable. In summary, the proposed model provides a set of Pareto urban growth solutions, which compromise environmental and economic issues for the Yangtze watershed.

Geographic variations of racial/ethnic disparities in cervical cancer mortality in Texas.

OBJECTIVES: To examine how racial/ethnic disparities of cervical cancer mortality vary geographically and to identify factors contributing to the variation. METHODS: Using the population-weighted risk difference, the authors investigated geographic patterns of racial/ethnic disparities in cervical cancer mortality in Texas based on data from 1995 to 2008 georeferenced at the census tract level. In addition, we considered the impact of seven factors--stage at diagnosis, spatial access to health care, and five factors that were created from available demographic data: socioeconomic status (SES), the sociodemographic factor, the percentage of African Americans, the health insurance factor, and the behavioral factor--on racial/ethnic disparities in the analysis using multivariate logistic regression. RESULTS: SES, the sociodemographic factor, the percentage of African Americans, and racial/ethnic disparities in late-stage diagnosis in a census tract were independent predictors of a census tract's displaying significant racial/ethnic disparities in cervical cancer mortality. Compared with a census tract with the highest SES, a census tract with the lowest SES was more likely to have higher mortality rates in African Americans (odds ratio 4.19, confidence interval 2.18-8.07) or Hispanics (odds ratio 8.15, confidence interval 5.27-12.61) than non-Hispanic whites after adjusting for covariates. Health insurance expenditures also influenced racial/ethnic disparities in mortality, although this effect was attenuated after adjusting for covariates. Neither our calculated behavioral factor nor spatial analysis of access to health care explained racial/ethnic gaps in mortality. CONCLUSIONS: Findings from this study could allow cervical cancer intervention programs to more clearly identify areas that would reduce disparities in cervical cancer outcomes.

Prenatal nitrate intake from drinking water and selected birth defects in offspring of participants in the national birth defects prevention study.

BACKGROUND: Previous studies of prenatal exposure to drinking-water nitrate and birth defects in offspring have not accounted for water consumption patterns or potential interaction with nitrosatable drugs. OBJECTIVES: We examined the relation between prenatal exposure to drinking-water nitrate and selected birth defects, accounting for maternal water consumption patterns and nitrosatable drug exposure. METHODS: With data from the National Birth Defects Prevention Study, we linked addresses of 3,300 case mothers and 1,121 control mothers from the Iowa and Texas sites to public water supplies and respective nitrate measurements. We assigned nitrate levels for bottled water from collection of representative samples and standard laboratory testing. Daily nitrate consumption was estimated from self-reported water consumption at home and work. RESULTS: With the lowest tertile of nitrate intake around conception as the referent group, mothers of babies with spina bifida were 2.0 times more likely (95% CI: 1.3, 3.2) to ingest ≥ 5 mg nitrate daily from drinking water (vs. < 0.91 mg) than control mothers. During 1 month preconception through the first trimester, mothers of limb deficiency, cleft palate, and cleft lip cases were, respectively, 1.8 (95% CI: 1.1, 3.1), 1.9 (95% CI: 1.2, 3.1), and 1.8 (95% CI: 1.1, 3.1) times more likely than control mothers to ingest ≥ 5.42 mg of nitrate daily (vs. < 1.0 mg). Higher water nitrate intake did not increase associations between prenatal nitrosatable drug use and birth defects. CONCLUSIONS: Higher water nitrate intake was associated with several birth defects in offspring, but did not strengthen associations between nitrosatable drugs and birth defects.

Identifying risk factors for disparities in breast cancer mortality among African-American and Hispanic women.

BACKGROUND: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005. METHODS: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality based on racial disparities in late-stage diagnosis and structured factors from the principal component analysis. RESULTS: Late-stage diagnosis, poverty factors, and demographic factors were found to be significant predictors of a census tract showing significant racial disparities in breast cancer mortality. Census tracts with higher poverty status were more likely to display significant racial disparities in breast cancer mortality for both African Americans (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.95-3.04) and Hispanics (OR, 5.30; 95% CI, 4.26-6.59). Spatial accessibility was not a consistent predictor of racial disparities in breast cancer mortality for African-American and Hispanic women. CONCLUSION: Physical access to mammography facilities does not necessarily reflect a greater utilization of mammogram screening, possibly owing to financial constraints. Therefore, a metric measuring access to health care facilities is needed to capture all aspects of access to preventive care. Despite easier physical access to mammography facilities in metropolitan areas, great resources and efforts should also be devoted to these areas where racial disparities in breast cancer mortality are often found.

Access to healthcare and disparities in colorectal cancer survival in Texas.

This paper reports a study examining the association between colorectal cancer (CRC) survival and access to healthcare in Texas using data from the Texas cancer registry. We geo-referenced the data to the census tract level and used an enhanced 2-step floating catchment area method and factor analysis to estimate people's spatial and non-spatial access to healthcare. In addition, Cox proportional hazard regression was employed to assess the influence of different factors on CRC survival, and a spatial scan statistic was used to investigate the geographic disparity of CRC survival and the influence of access to healthcare. The analyses revealed that Hispanics, non-Hispanic blacks, and residents from several regions in Texas were more likely to die from CRC than others. Disadvantaged population groups based on factors rather than spatial access had an increased risk of CRC-specific mortality. Spatial access to oncologists has a significant association with CRC survival in non-urban areas but not in urban areas. Geographic disparities of CRC survival were largely influenced by factors rather than spatial access to healthcare.

[Maternal sulfur dioxide exposure and the risk of low birth-weight babies].

The relationship between maternal exposure to sulfur dioxide (SO2) and the risk of low birth-weight (LBW) babies which has been reported in literatures remained inconclusive. In this study, the data on SO2 emission, meteorology, topography as well as LBW and control babies in the Dallas-Fort Worth area of the United States in 1997 were collected to re-examine the associations between maternal SO2 exposure and the risk of LBW in babies. A combination of air dispersion modeling, Geographic Information System (GIS) spatial interpolation and geo-statistical analysis, as well as logistic regression was used for analyses. Results showed that the risk of LBW was not significantly increased with the exposure of pregnant mothers to higher level of SO2 when all data were considered together as one group. However, for mothers at the age 35 or older, the risk of LBW babies was higher in exposure to SO2 (OR = 2.31, 95% CI 1.01 - 5.30). Therefore, the potential risk of LBW baby might be higher in elder women in exposure to SO2 during pregnancy.