Factors associated with mammography utilization in Sao Paulo and Mexico city elderly females

Introduction. Breast cancer has the highest incidence and mortality rates of all cancers in Sao Paulo and Mexico City women with rates expected to rise due to increasing elderly populations. While mammograms could reduce the breast cancer burden, little information exists about screening behavior factors in these areas. The primary objective of this study is testing the association of socio-demographic, geographic, and health access/health status variables on mammogram screenings in elderly females in both cities. Studying the regions' healthcare systems and their screening impact is the ancillary objective. ^ Methods. Accounting for the complex sample design (weights, stratification, and clusters) of the 1999-2000 SABE study, analysis of mammogram utilization in the past two years was performed. The sample consisted of 1239 women from Sao Paulo and 1349 women from Mexico City. ^ Results. Having private insurance in Sao Paulo (OR = 5.86) and Mexico City (OR = 4.09) increased the chance of having a mammogram in the targeted women. In both cities, women with higher levels of education had higher likelihoods of screening (Sao Paulo OR = 4.56 and Mexico City OR = 3.04). Age, regular medical care, and health status were significant in Sao Paulo; however, the factors showed no significance in Mexico City. ^ Discussion. Mammogram utilization can reduce mortality from breast cancer, and understanding screening factors is crucial to screening adherence. Addressing key variables may lead to increased screening and decreased breast cancer mortality in elderly women in Sao Paulo, Mexico City, and similar regions. ^

Environmental tobacco smoke exposure, respiratory and cardiovascular health in restaurant and bar workers in Mexico

Environmental tobacco smoke (ETS) is a well established health hazard, being causally associated to lung cancer and cardiovascular disease. ETS regulations have been developed worldwide to reduce or eliminate exposure in most public places. Restaurants and bars constitute an exception. Restaurants and bar workers experience the highest ETS exposure levels across several occupations, with correspondingly increased health risks. In Mexico, previous exposure assessment in restaurants and bars showed concentrations in bars and restaurants to be the highest across different public and workplaces. Recently, Mexico developed at the federal level the General Law for Tobacco Control restricting indoors smoking to separated areas. AT the local level Mexico City developed the Law for the Protection of Non-smokers Health, completely banning smoking in restaurants and bars. Studies to assess ETS exposure in restaurants and bars, along with potential health effects were required to evaluate the impact of these legislative changes and to set a baseline measurement for future evaluations.^ A large cross-sectional study conducted in restaurants and bars from four Mexican cities was conducted from July to October 2008, to evaluate the following aims: Aim 1) Explore the potential impact of the Mexico City ban on ETS concentrations through comparison of Mexico City with other cities. Aim 2). Explore the association between ETS exposure, respiratory function indicators and respiratory symptoms. Aim 3). Explore the association between ETS exposure and blood pressure and heart rate.^ Three cities with no smoking ban were selected: Colima (11.5% smoking prevalence), Cuernavaca (21.5% smoking prevalence) and Toluca (27.8% smoking prevalence). Mexico City (27.9% smoking prevalence), the only city with a ban at the time of the study, was also selected. Restaurants and bars were randomly selected from municipal records. A goal of 26 restaurants and 26 bars per city was set, 50% of them under 100 m2. Each establishment was visited during the highest occupancy shift, and managers and workers answered to a questionnaire. Vapor-phase nicotine was measured using passive monitors, that were activated at the beginning and deactivated at the end of the shift. Also, workers participated at the beginning and end of the shift in a short physical evaluation, comprising the measurement of Forced Expiratory Volume in the first second (FEV1) and Peak Expiratory Flow (PEF), as well as blood pressure and heart rate.^ A total of 371 establishments were invited, 219 agreed to participate for a 60.1% participation rate. In them, 828 workers were invited, 633 agreed to participate for a 76% participation rate. Mexico City had at least 4 times less nicotine compared to any of the other cities. Differences between Mexico City and other cities were not explained by establishment characteristics, such as ventilation or air extraction. However, differences between cities disappeared when ban mechanisms, such as policy towards costumer's smoking, were considered in the models. An association between ETS exposure and respiratory symptoms (cough OR=1.27, 95%CI=1.04, 1.55) and respiratory illness (asthma OR=1.97, 95%CI=1.20, 3.24; respiratory illness OR=1.79, 95%CI=1.10, 2.94) was observed. No association between ETS and phlegm, wheezing or respiratory infections was observed. No association between ETS and any of the spirometric indicators was observed. An association between ETS exposure and increased systolic and diastolic blood pressure at the end of the shift was observed among non-smokers (systolic blood pressure beta=1.51, 95%CI=0.44, 2.58; diastolic blood pressure beta=1.50, 95%CI=0.72, 2.28). The opposite effect was observed in heavy smokers, were increased ETS exposure was associated with lower blood pressure at the end of the shift (systolic blood pressure beta=1.90, 95%CI=-3.57, -0.23; diastolic blood pressure beta=-1.46, 95%CI=-2.72, -0.02). No association in light smokers was observed. No association for heart rate was observed. ^ Results from this dissertation suggest Mexico City's smoking ban has had a larger impact on ETS exposure. Ventilation or air extraction, mechanisms of ETS control suggested frequently by tobacco companies to avoid smoking bans were not associated with ETS exposure. This dissertation suggests ETS exposure could be linked to changes in blood pressure and to increased respiratory symptoms. Evidence derived from this dissertation points to the potential negative health effects of ETS exposure in restaurants and bars, and provides support for the development of total smoking bans in this economic sector. ^

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.^

Ethnographic and epidemiologic approaches for the programming of prenatal and birth services in Mesa los Hornos, Mexico

The investigator conducted an action-oriented investigation of pregnancy and birth among the women of Mesa los Hornos, an urban squatter slum in Mexico City. Three aims guided the project: (1) To obtain information for improving prenatal and maternity service utilization; (2) To examine the utility of rapid ethnographic and epidemiologic assessment methodologies; (3) To cultivate community involvement in health development.^ Viewing service utilization as a culturally-bound decision, the study included a qualitative phase to explore women's cognition of pregnancy and birth, their perceived needs during pregnancy, and their criteria of service acceptability. A probability-based community survey delineated parameters of service utilization and pregnancy health events, and probed reasons for decisions to use medical services, lay midwives, or other sources of prenatal and labor and delivery assistance. Qualitative survey of service providers at relevant clinics, hospitals, and practices contributed information on service availability and access, and on coordination among private, social security, and public assistance health service sectors. The ethnographic approach to exploring the rationale for use or non-use of services provided a necessary complement to conventional barrier-based assessment, to inform planning of culturally appropriate interventions.^ Information collection and interpretation was conducted under the aegis of an advisory committee of community residents and service agency representatives; the residents' committee formulated recommendations for action based on findings, and forwarded the mandate to governmental social and urban development offices. Recommendations were designed to inform and develop community participation in health care decision-making.^ Rapid research methods are powerful tools for achieving community-based empowerment toward investigation and resolution of local health problems. But while ethnography works well in synergy with quantitative assessment approaches to strengthen the validity and richness of short-term field work, the author strongly urges caution in application of Rapid Ethnographic Assessments. An ethnographic sensibility is essential to the research enterprise for the development of an active and cooperative community base, the design and use of quantitative instruments, the appropriate use of qualitative techniques, and the interpretation of culturally-oriented information. However, prescribed and standardized Rapid Ethnographic Assessment techniques are counter-productive if used as research short-cuts before locale- and subject-specific cultural understanding is achieved. ^

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.^

PCR-based assay using occult blood detection cards for detection of diarrheagenic Escherichia coli in specimens from U.S. travelers to Mexico with acute diarrhea.

Large field studies of travelers' diarrhea for multiple destinations are limited by the need to perform stool cultures on site in a timely manner. A method for the collection, transport, and storage of fecal specimens that does not require immediate processing and refrigeration and that is stable for months would be advantageous. This study was designed to determine if enterotoxigenic Escherichia coli (ETEC) and enteroaggregative E. coli (EAEC) DNA could be identified from cards that were processed for the evaluation of fecal occult blood. U.S. students traveling to Mexico during 2005 to 2007 were monitored for the occurrence of diarrheal illness. When ill, students provided a stool specimen for culture and occult blood by the standard methods. Cards then were stored at room temperature prior to DNA extraction. Fecal PCR was performed to identify ETEC and EAEC in DNA extracted from stools and from occult blood cards. Significantly more EAEC cases were identified by PCR that was performed on DNA that was extracted from cards (49%) or from frozen feces (40%) than from culture methods that used HEp-2 adherence assays (13%) (P < 0.001). Similarly, more ETEC cases were detected from card DNA (38%) than from fecal DNA (30%) or by culture that was followed by hybridization (10%) (P < 0.001). The sensitivity and specificity of the card test were 75 and 62%, respectively, compared to those for EAEC by culture and were 50 and 63%, respectively, compared to those for ETEC. DNA extracted from fecal cards that was used for the detection of occult blood is of use in identifying diarrheagenic E. coli.

Influence of host interleukin-10 polymorphisms on development of traveler's diarrhea due to heat-labile enterotoxin-producing Escherichia coli in travelers from the United States who are visiting Mexico.

Up to 60% of U.S. visitors to Mexico develop traveler's diarrhea (TD), mostly due to enterotoxigenic Escherichia coli (ETEC) strains that produce heat-labile (LT) and/or heat-stable (ST) enterotoxins. Distinct single-nucleotide polymorphisms (SNPs) within the interleukin-10 (IL-10) promoter have been associated with high, intermediate, or low production of IL-10. We conducted a prospective study to investigate the association of SNPs in the IL-10 promoter and the occurrence of TD in ETEC LT-exposed travelers. Sera from U.S. travelers to Mexico collected on arrival and departure were studied for ETEC LT seroconversion by using cholera toxin as the antigen. Pyrosequencing was performed to genotype IL-10 SNPs. Stools from subjects who developed diarrhea were also studied for other enteropathogens. One hundred twenty-one of 569 (21.3%) travelers seroconverted to ETEC LT, and among them 75 (62%) developed diarrhea. Symptomatic seroconversion was more commonly seen in subjects who carried a genotype producing high levels of IL-10; it was seen in 83% of subjects with the GG genotype versus 54% of subjects with the AA genotype at IL-10 gene position -1082 (P, 0.02), in 71% of those with the CC genotype versus 33% of those with the TT genotype at position -819 (P, 0.005), and in 71% of those with the CC genotype versus 38% of those with the AA genotype at position -592 (P, 0.02). Travelers with the GCC haplotype were more likely to have symptomatic seroconversion than those with the ATA haplotype (71% versus 38%; P, 0.002). Travelers genetically predisposed to produce high levels of IL-10 were more likely to experience symptomatic ETEC TD.

Saturday Morning Television Advertisements Aired on English and Spanish Language Networks along the Texas-Mexico Border

Objectives: The aim of this content analysis study is to characterize the TV advertisements aired to an at-risk child population along the Texas-Mexico border. Methods: We characterized the early Saturday morning TV advertisements aired by three broadcast network categories (U.S. English language, U.S. Spanish language, and Mexican Spanish language) in Spring 2010. The number, type (food related vs. non-food related), target audience, and persuasion tactics used were recorded. Advertised foods, based on nutrition content, were categorized as meeting or not meeting current dietary guidelines. Results: Most commercials were non-food related (82.7%, 397 of 480). The majority of the prepared foods (e.g., cereals, snacks, and drinks) advertised did not meet the current U.S. Dietary Guidelines. Additionally, nutrition content information was not available for many of the foods advertised on the Mexican Spanish language broadcast network category. Conclusions: For U.S. children at risk for obesity along the Texas-Mexico border exposure to TV food advertisements may result in the continuation of sedentary behavior as well as an increased consumption of foods of poor nutritional quality. An international regulatory effort to monitor and enforce the reduction of child-oriented food advertising is needed. Editors' Note: This article was submitted in response to the first issue of the Journal of Applied Research on Children: Latino Children.

Development of a rapid bioassessment method and index of biotic integrity for estuaries located along the northwest Gulf of Mexico

Recently it has been proposed that the evaluation of effects of pollutants on aquatic organisms can provide an early warning system of potential environmental and human health risks (NRC 1991). Unfortunately there are few methods available to aquatic biologists to conduct assessments of the effects of pollutants on aquatic animal community health. The primary goal of this research was to develop and evaluate the feasibility of such a method. Specifically, the primary objective of this study was to develop a prototype rapid bioassessment technique similar to the Index of Biotic Integrity (IBI) for the upper Texas and Northwestern Gulf of Mexico coastal tributaries. The IBI consists of a series of "metrics" which describes specific attributes of the aquatic community. Each of these metrics are given a score which is then subtotaled to derive a total assessment of the "health" of the aquatic community. This IBI procedure may provide an additional assessment tool for professionals in water quality management.^ The experimental design consisted primarily of compiling previously collected data from monitoring conducted by the Texas Natural Resource Conservation Commission (TNRCC) at five bayous classified according to potential for anthropogenic impact and salinity regime. Standardized hydrological, chemical, and biological monitoring had been conducted in each of these watersheds. The identification and evaluation of candidate metrics for inclusion in the estuarine IBI was conducted through the use of correlation analysis, cluster analysis, stepwise and normal discriminant analysis, and evaluation of cumulative distribution frequencies. Scores of each included metric were determined based on exceedances of specific percentiles. Individual scores were summed and a total IBI score and rank for the community computed.^ Results of these analyses yielded the proposed metrics and rankings listed in this report. Based on the results of this study, incorporation of an estuarine IBI method as a water quality assessment tool is warranted. Adopted metrics were correlated to seasonal trends and less so to salinity gradients observed during the study (0-25 ppt). Further refinement of this method is needed using a larger more inclusive data set which includes additional habitat types, salinity ranges, and temporal variation. ^

Patterns of alcohol and illicit substance use in the United States and Mexico. Substantive and methodologic issues in the cross-national analysis of alcohol and drug use data

This research examines prevalence of alcohol and illicit substance use in the United States and Mexico and associated socio-demographic characteristics. The sources of data for this study are public domain data from the U.S. National Household Survey of Drug Abuse, 1988 (n = 8814), and the Mexican National Survey of Addictions, 1988 (n = 12,579). In addition, this study discusses methodologic issues in cross-cultural and cross-national comparison of behavioral and epidemiologic data from population-based samples. The extent to which patterns of substance abuse vary among subgroups of the U.S. and Mexican populations is assessed, as well as the comparability and equivalence of measures of alcohol and drug use in these national samples.^ The prevalence of alcohol use was somewhat similar in the two countries for all three measures of use: lifetime, past year and past year heavy use, (85.0%, 68.1%, 39.6% and 72.6%, 47.7% and 45.8% for the U.S. and Mexico respectively). The use of illegal substances varied widely between countries, with U.S. respondents reporting significantly higher levels of use than their Mexican counterparts. For example, reported use of any illicit substance in lifetime and past year was 34.2%, 11.6 for the U.S., and 3.3% and 0.6% for Mexico. Despite these differences in prevalence, two demographic characteristics, gender and age, were important correlates of use in both countries. Men in both countries were more likely to report use of alcohol and illicit substances than women. Generally speaking, a greater proportion of respondents in both countries 18 years of age or older reported use of alcohol for all three measures than younger respondents; and a greater proportion of respondents between the ages of 18 and 34 years reported use of illicit substances during lifetime and past year than any other age group.^ Additional substantive research investigating population-based samples and at-risk subgroups is needed to understand the underlying mechanisms of these associations. Further development of cross-culturally meaningful survey methods is warranted to validate comparisons of substance use across countries and societies. ^

Relationship between enterotoxigenic Escherichia coli and travelers' diarrhea in Mexico, from 1992 to 1997

The purpose of this study was to examine the relationship between enterotoxigenic ETEC and travelers' diarrhea over a period of five years in Guadalajara, Mexico. Specifically, this study identified and characterized ETEC from travelers with diarrhea. The objectives were to study the colonization factor antigens, toxins and antibiotic sensitivity patterns in ETEC from 1992 to 1997 and to study the molecular epidemiology of ETEC by plasmid content and DNA restriction fragment patterns. ^ In this survey of travelers' diarrhea in Guadalajara, Mexico, 928 travelers with diarrhea were screened for enteric pathogens between 1992 and 1997. ETEC were isolated in 195 (19.9%) of the patients, representing the most frequent enteric pathogen identified. ^ A total of 31 antimicrobial susceptibility patterns were identified among ETEC isolates over the five-year period. ^ The 195 ETEC isolates contained two to six plasmids each, which ranged in size from 2.0 to 23 kbp. ^ Three different reproducible rRNA gene restriction patterns (ribotypes R-1 to R-3) were obtained among the 195 isolates with the enzyme, HindIII. ^ Colonization factor antigens (CFAs) were identified in 99 (51%) of the 195 ETEC strains studied. ^ Cluster analysis of the observations seen in the four assays all confirmed the five distinct groups of study-year strains of ETEC. Each group had a >95% similarity level of strains within the group and <60% similarity level between the groups. In addition, discriminant analysis of assay variables used in predicting the ETEC strains, reveal a >80% relationship between both the plasmid and rRNA content of ETEC strains and study-year. ^ These findings, based on laboratory observations of the differences in biochemical, antimicrobial susceptibility, plasmid and ribotype content, suggest complex epidemiology for ETEC strains in a population with travelers' diarrhea. The findings of this study may have implications for our understanding of the epidemiology, transmission, treatment, control and prevention of the disease. It has been suggested that an ETEC vaccine for humans should contain the most prevalent CFAs. Therefore, it is important to know the prevalence of these factors in ETEC in various geographical areas. ^ CFAs described in this dissertation may be used in different epidemiological studies in which the prevalence of CFAs and other properties on ETEC will be evaluated. Furthermore, in spite of an intense search in near 200 ETEC isolates for strains that may have clonal relationship, we failed to identify such strains. However, further studies are in progress to construct suitable live vaccine strains and to introduce several of CFAs in the same host organism by recombinant DNA techniques (Dr. Ann-Mari Svennerholm's lab). (Abstract shortened by UMI.)^

Alcohol consumption and breast cancer risk among Hispanic and non-Hispanic women in New Mexico

Breast cancer incidence and mortality rates for Hispanic women are lower than for non-Hispanic white (NHW) women, but recently rates have increased more rapidly among Hispanic women. Many studies have shown a consistent increased breast cancer risk associated with modest or high alcohol intake, but few included Hispanic women. Alcohol consumption and risk of breast cancer was investigated in a New Mexico statewide population-based case-control study. The New Mexico Tumor Registry ascertained women, newly diagnosed with breast cancer (1992–1994) aged 30–74 years. Controls were identified by random digit dialing and were frequency-matched for ethnicity, age-group, and health planning district. In-person interviews of 712 cases and 844 controls were conducted. Data were collected for breast cancer risk factors, including alcohol intake. Recent alcohol intake data was collected for a four-week period, six months prior to interview. Past alcohol intake included information on alcohol consumption at ages 25, 35, and 50. History of alcohol consumption was reported by 81% of cases and 85% of controls. Of these women, 42% of cases and 48% of controls reported recent alcohol intake. Results for past alcohol intake did not show any trend with breast cancer risk, and were nonsignificant. Multivariate-adjusted odds ratios for recent alcohol intake and breast cancer suggested an increased risk at the highest level for both ethnic groups, but estimates were unstable and statistically nonsignificant. Low level of recent alcohol intake (<148 grams/week) was associated with a reduced risk for NHW women (Odds Ratio (OR) = 0.49 95% Confidence Interval (CI) 0.35–0.69). This pattern was independent of hormone-receptor status. The reduced breast cancer risk for low alcohol intake was present for premenopausal (OR = 0.29, 95% CI 0.15–0.56) and postmenopausal NHW women (OR = 0.56, 95% CI 0.35–0.90). The possibility of an increased risk associated with high alcohol intake could not be adequately addressed, because there were few drinkers with more than light to moderate intake, especially among Hispanic women. An alcohol-estrogen link is hypothesized to be the mechanism responsible for increased breast cancer risk, but has not been consistently substantiated. More studies are needed of the underlying mechanism for an association between alcohol intake and breast cancer. ^

Neural tube defects in Mexican-Americans living on the US-Mexico border: The effects of folic acid and dietary folate

Neural tube defects (NTDs) are malformations of the developing brain and spinal cord; the most common are anencephaly and spina bifida. Evidence from many populations suggests that 50% of NTDs can be prevented through daily consumption of folic acid. A recent study has reported that folic acid may not protect populations of Mexican descent. This finding has serious implications for women living along the US-Mexico border. Not only is risk high in these Mexican American women compared with other US women; they also differ markedly in supplemental folic acid and dietary folate consumption, and in NTD-related risks (e.g., obesity, diabetes). This case-control study investigated whether folic acid supplements and dietary folate reduces NTDs in Mexican Americans. Cases included liveborn, stillborn, electively and spontaneously aborted NTD-affected fetuses and infants occurring in the 14-county Texas-Mexico border. Controls were randomly selected from unaffected live births, frequency matched to cases by hospital and year. An in-person interview of 110 case and 113 control mothers solicited data on folic acid supplements, dietary folate, and other covariates. Consumption of folic acid-containing vitamins before conception was only 5% for both case and control women. Taking vitamins the trimester before conception had no apparent effect, after adjusting for covariates [odds ratio (OR) = 1.0, 95% confidence interval (CI) = 0.3–3.4]. Combining folate from vitamins and diet showed a 20% risk reduction for women consuming at least 400 μg of folate daily [OR = 0.8, 95% CI = 0.5–1.5]; however, this estimate is statistically indistinguishable from the null. Although consistent with an inherent ineffectiveness of supplemental folic acid, that so few women consumed multivitamins during the critical time severely limited the assessment of folic acid in this population. A reduced folate response in Mexican descent women may be due to a genetic heterogeneity for metabolizing folate. Alternatively, folate intakes may be insufficient to overcome other underlying risk factors. In conclusion, determining whether folic acid reduces NTD risk in Mexican American women requires further study in populations with higher folic acid exposures. Meanwhile, we should pursue all recommended prevention strategies to reduce risk, including motivating Mexican American women of childbearing age to take folic acid routinely. ^

THE NATURAL BACKGROUND GAMMA RADIATION EXPOSURE IN THE METROPOLITAN AREA OF THE VALLEY OF MEXICO

Measurements of the natural background radiation have been made at numerous places throughout the world. Very little work in this field has been done in developing countries. In Mexico the natural radiation to which the population is exposed has not been assessed. This dissertation represents a pioneer study in this environmental area. The radiation exposure which occupants within buildings receive as a result of naturally occurring radionuclides present in construction materials is the principal focus.^ Data were collected between August 1979 and November 1980. Continuous monitoring was done with TLDs placed on site for periods of 3 to 6 months. The instrumentation used for "real-time" measurements was a portable NaI (Tl) scintillation detector. In addition, radiometric measurements were performed on construction materials commonly used in Mexican homes.^ Based on TLD readings taken within 75 dwellings, the typical indoor exposure for a resident of the study area is 9.2 (mu)Rh('-1). The average reading of the 152 indoor scintillometer surveys was 9.5 (mu)Rh('-1), the outdoor reading 7.5 (mu)Rh('-1). Results of one-way and multi-way analyses of the exposure data to determine the effect due to building materials type, geologic subsoil, age of dwelling, and elevation are also presented. The results of 152 indoor scintillometer surveys are described. ^

Determinants of quality of advanced cancer care in Latin America. A look at five countries: Argentina, Brazil, Cuba, Mexico and Peru

The World Health Organization reports that nearly half a million people died of cancer in Latin America in 2001. As a growing public health problem, cancer is now either the first or second leading cause of death among adults in most Latin American nations. Despite these trends, information on the quality of care people with advanced cancer in Latin America receive has been limited. This study assessed the quality of advanced cancer care in diverse Latin American countries and institutions by surveying cancer care providers from: Argentina; Brazil; Cuba; Mexico; and Peru. This study also identified the most salient factors that influence the quality of this care at the national and institutional levels and compared these factors across countries. This study was based on the secondary analyses of data collected by the University of Texas M. D. Anderson's WHO/PAHO Collaborating Center in Supportive Cancer Care from March 2000 to November 2002. The sample for this survey was a convenience sample of physicians and nurses who treat cancer patients in these regions. Strategies for the dissemination of this survey included: mass mailings; distribution at professional meetings/conferences; collaboration with regional institutions, professional organizations and PAHO; and the posting of online surveys. The strongest predictor of providers' assessments of the quality of advanced cancer care was their ratings of access to care. This major finding reflects a shared equitable notion of quality care among providers from diverse countries and medical institutions that is highly interrelated with providing accessible care to those with advanced cancer. Higher ratings of the affordability of care, an increased reported availability of end-of-life services and opioid analgesics, practicing in either a private hospital or specialized cancer center, and practicing in Cuba were also associated with higher provider ratings of the quality of advanced cancer care. The findings of this study contribute towards the much needed body of knowledge that may guide the formulation of policies and interventions aimed at improving the care for people with advanced cancer in Latin America. ^