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The impact on vitamin A deficiency (VAD), wasting malnutrition, and excessive childhood mortality of two alternative approaches - nutrition education and mega-dose capsule distribution (6-12-month-olds:: 100 000 IU;-1-5-year-olds: 200 000 [...]

Background: While national surveys have found that African-Americans have a higher prevalence and severity of dental caries than white-Americans, there are only a few descriptive studies of the prevalence and severity of dental caries in low-income urban African-Americans. Objectives: This study assessed the prevalence, severity and determinants of dental caries, using the International Caries Detection and Assessment System (ICDAS). Methods: A representative sample of low-income families (a caregiver and a child aged 0-5 years) was selected from low-income census tracts in the city of Detroit, Michigan. Of the 12,655 randomly selected housing units, 10,695 were occupied and 9781 were successfully contacted (91.5%). There were 1386 families with eligible children in the contacted households; and of those, 1021 were interviewed and examined at a permanent examination center organized for this study. This represents an overall response rate of 73.7%. At the center, trained staff interviewed the main caregivers of the selected children, and trained and calibrated dentists examined the caregiver and her/his child. Data used in this study included information gathered from the social, behavioral and parenting questionnaires, the Block Food Frequency Questionnaire (total sugar intake), and data collected from community and census databases. Results: Over 90% of the adults (ages 14-70 years, average 29.3) had at least one noncavitated carious lesion and 82.2% had at least one primary cavitated lesion. Negative binomial regression models found that the age of caregivers and the number of churches in neighborhoods were negatively associated with the number of noncavitated tooth surfaces. Cavitated tooth surfaces were positively associated with age, oral hygiene status, being worried about teeth, a recent visit to a dentist, and the number of grocery stores in the neighborhoods. However, the number of cavitated tooth surfaces was negatively associated with preventive dental visits, positive rating of oral health status and the number of dentists in a community. Conclusions: Dental caries, especially at the noncavitated stage, is highly prevalent in low-income African-American adults in Detroit. A significant increase in the mean number of missing teeth was observed after the age of 34 years. This study found that different individual, social, and community risk indicators were associated with noncavitated versus cavitated tooth surfaces. [ABSTRACT FROM AUTHOR]

Context: A prominent hypothesis regarding social inequalities in mortality is that the elevated risk among the socioeconomically disadvantaged is largely due to the higher prevalence of health risk behaviors among those with lower levels of education and income.Objective: To investigate the degree to which 4 behavioral risk factors (cigarette smoking, alcohol drinking, sedentary lifestyle, and relative body weight) explain the observed association between socioeconomic characteristics and all-cause mortality.Design: Longitudinal survey study investigating the impact of education, income, and health behaviors on the risk of dying within the next 7.5 years.Participants: A nationally representative sample of 3617 adult women and men participating in the Americans' Changing Lives survey.Main Outcome Measure: All-cause mortality verified through the National Death Index and death certificate reviews.Results: Educational differences in mortality were explained in full by the strong association between education and income. Controlling for age, sex, race, urbanicity, and education, the hazard rate ratio of mortality was 3.22 (95% confidence interval [CI], 2.01-5.16) for those in the lowest-income group and 2.34 (95% CI, 1.49-3.67) for those in the middle-income group. When health risk behaviors were considered, the risk of dying was still significantly elevated for the lowest-income group (hazard rate ratio, 2.77; 95% CI, 1.74-4.42) and the middle-income group (hazard rate ratio, 2.14; 95% CI, 1.38-3.25).Conclusion: Although reducing the prevalence of health risk behaviors in low-income populations is an important public health goal, socioeconomic differences in mortality are due to a wider array of factors and, therefore, would persist even with improved health behaviors among the disadvantaged. [ABSTRACT FROM AUTHOR]

The authors studied weighting adjustments for the National Comorbidity Survey (1990–1992), a large-scale national epidemiologic investigation of the prevalence, risk factors, and consequences of psychiatric morbidity and comorbidity in the United States. Weighting adjustments for differential selection within households, new construction, unit nonresponse, and poststratification were examined separately and in combination. Specific issues addressed included the magnitude of the bias incurred from ignoring the weights, the added variance from weighting and how well this was predicted by simple formulae, and the performance of methods for trimming the weights. Weights had quite modest effects on point estimates of prevalences but resulted in major increases in variance unless trimmed. The weights after trimming and poststratification appeared to work well. It is suggested that the added variance from weighting be carefully monitored in similar surveys. Alternatives to the use of trimming for controlling variance are worth exploring. [ABSTRACT FROM AUTHOR]

Objective To assess mental health symptoms, suicidal ideation/behaviors, and treatment among a nationally representative probability sample of student veterans. Participants : Student veterans enrolled in post-secondary educational institutions and matched comparison students. Methods: Sampled participants completed an online survey (n = 1,838). Analyses accounted for the complex sample design and non-response. Results : Substantial percentages of student veterans screened positive for: depression (36.9%, 95% CI: 31.1-42.7), PTSD (35.7%, 95% CI 29.9-41.5), anxiety (29.5%, 95% CI 26.8-32.2), and suicidal ideation (14.6%, 95% CI 12.1-17.1), with student veterans having odds ratios between 1.7 to 2.4 for positive screens compared to non-veteran students. Only 41.5% (95% CI 33.0-50.0) of student veterans with positive screens received treatment, although they had 50% higher odds of receiving treatment than non-veteran students. Conclusions: Student veterans have high rates of mental health symptoms and low rates of treatment. However, they are more likely to receive treatment than comparison students.

HIV infection increases the risk of psychological distress among adolescents living with HIV (ALHIV), which, in turn, increases risky behaviours such as medication non-adherence, substance use, and sexual risk-taking. The majority of studies on psychological distress among ALHIV have been conducted in high-income countries; data on the prevalence and correlates of psychological distress among ALHIV in sub-Saharan Africa (SSA) are scarce, yet over two-thirds of the global population of ALHIV resides in SSA. The purpose of this study was to identify the contextually relevant correlates of psychological distress among Ugandan ALHIV. Utilizing the stress and coping framework, we explored the risk and protective factors for psychological distress in cross-sectional sample of 464 ALHIV (aged 12-19; 53% female) at a large HIV treatment centre in Kampala, Uganda. The stressors associated with psychological distress included daily hassles, major negative life events, HIV-related quality of life, and stigma. Protective factors included psychosocial resources such as religious coping, satisfaction with social support, and general coping style and behaviours. Social support and optimism were significantly associated with psychological distress. Findings underscore the need for mental health services for ALHIV in Uganda and other resource-limited settings.

Despite major improvements over the past several decades, many patients undergoing hematopoietic stem cell transplantations (HSCT) continue to suffer from significant treatment-related morbidity and mortality. Clinical research studies (trials) have been integral to advancing the standard of care in HSCT. However, 1 of the biggest challenges with clinical trials is the low participation rate. Although barriers to participation in cancer clinical trials have been previously explored, studies specific to HSCT are lacking. The current study was undertaken to examine the knowledge, attitudes, and perceptions of HSCT patients regarding clinical trials. As members of focus groups, participants responded to open-ended questions that assessed factors influencing decision-making about HSCT clinical trials. Suggestions for improvements in the recruitment process were also solicited among participants. Seventeen adult HSCT patients and 6 parents of pediatric HSCT patients participated in the study. The median age was 56 years (range, 18 to 70) and 44 years (range, 28 to 54) for adult patients and parents, respectively. Participants universally indicated that too much information was provided within the informed consents and they were intimidated by the medical and legal language. Despite the large amount of information provided to them at the time of study enrollment, the participants had limited knowledge retention and recall of study details. Nevertheless, participants reported overall positive experiences with clinical trial participation and many would readily choose to participate again. A common concern among participants was the uncertainty of study outcome and general lack of feedback about results at the end of the study. Participants suggested that investigators provide more condensed and easier to understand informed consents and follow-up of study findings. These findings could be used to help guide the development of improved consent documents and enhanced participation in research studies, thereby affecting the future design of HSCT research protocols., (Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)

As part of the University of Michigan Dioxin Exposure Study, soil, household dust, and serum samples were collected from more than 750 households in five populations around the city of Midland and in Jackson and Calhoun Counties, Michigan, USA. Polytopic vector analysis, a type of receptor model, was applied to better understand the potential sources of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans found in these samples and to quantify the contributions of the sources in each matrix across populations. The results indicated that source signatures found in soil are similar to those found in dust, reflecting various combustion profiles, pentachlorophenol, and graphite electrode sludge. The profiles associated with contamination in the Tittabawassee River, likely related to historical discharges from the Dow Chemical Company facility in Midland, exhibited the largest differences among the regional populations sampled. Differences in serum source contributions among the study populations were consistent with some of the regional differences observed in soil samples. However, the age trends of these differences suggested that they are related to past exposures, rather than ongoing sources., (Copyright © 2012 SETAC.)

The University of Michigan Dioxin Exposure Study was undertaken to address concerns that the industrial discharge of dioxin-like compounds in the Midland, Michigan, USA area had resulted in the contamination of soil and vegetation in the Tittabawassee River floodplain and downwind of the incinerator in the City of Midland. The study included the analysis of 597 vegetation samples, predominantly grass and weeds, from residential properties selected through a multistage probabilistic sample design in the Midland area, and in Jackson and Calhoun Counties (Michigan), as a background comparison, for 29 polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs). The mean toxic equivalent (TEQ) of the house perimeter vegetation samples ranged from 4.2 to 377 pg/g. The ratio of TEQs (vegetation to soil) was about 0.3, with a maximum of 3.5. Based on a calculation of the similarity of the congener patterns between the soil and the vegetation, it appeared that the source of the contamination on the vegetation was the surrounding soil. This conclusion was supported by linear regression analysis, which showed that the largest contributor to the R(2) for the outcome variable of log(10) of the vegetation concentration was log(10) of the surrounding soil concentration. Models of vegetation contamination usually focus on atmospheric deposition and partitioning. The results obtained here suggest that the deposition of soil particles onto vegetation is a significant route of contamination for residential herbage. Thus, the inclusion of deposition of soil particles onto vegetation is critical to the accurate modeling of contamination residential herbage in communities impacted by historic industrial discharges of persistent organic compounds., (Copyright © 2010 SETAC.)

Context: Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls that have toxic equivalency factors (TEFs) were measured in serum of 946 subjects in five Michigan counties. The study was motivated by concerns about human exposure to dioxin-contaminated sediments in the Tittabawassee River (TR). Most of the toxic equivalency in TR sediments is from two furan congeners, 2,3,7,8-tetrachlorodibenzofuran and 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-pentaCDF)., Case Presentation: The individual with the highest adjusted (for age, age squared, and body mass index) serum level of 2,3,4,7,8-pentaCDF in the study (42.5 ppt) reported a unique history of raising cattle and vegetables in the floodplain of the TR. Interviews and serum samples were obtained from the index case and 15 other people who ate beef and vegetables raised by the index case. 2,3,4,7,8-pentaCDF in beef lipid was estimated to have been more than three orders of magnitude greater than background (1,780 vs. 1.1 ppt). The mean, median, and 95th percentile for serum 2,3,4,7,8-pentaCDF in the study control population were 6.0, 5.4, and 13.0 ppt, respectively, and were 9.9, 8.4, and 20.5 ppt among beef and vegetable consumers, respectively. Back extrapolation for the index case suggests that his increase in serum concentration of 2,3,4,7,8-pentaCDF above background may have been as high as 146 ppt., Discussion: Consumption of beef and/or vegetables raised on dioxin-contaminated soil may be an important completed pathway of exposure. RELEVANCE TO PUBLIC HEALTH PRACTICE: Animals and crops should not be raised for human consumption in areas contaminated with dioxins.

Background: Data with some values below a limit of detection (LOD) can be analyzed using methods of survival analysis for left-censored data. The reverse Kaplan-Meier (KM) estimator provides an effective method for estimating the distribution function and thus population percentiles for such data. Although developed in the 1970s and strongly advocated since then, it remains rarely used, partly due to limited software availability., Methods: In this paper, the reverse KM estimator is described and is illustrated using serum dioxin data from the University of Michigan Dioxin Exposure Study (UMDES) and the National Health and Nutrition Examination Survey (NHANES). Percentile estimates for left-censored data using the reverse KM estimator are compared with replacing values below the LOD with the LOD/2 or LOD/ radical2., Results: When some LODs are in the upper range of the complete values, and/or the percent censored is high, the different methods can yield quite different percentile estimates. The reverse KM estimator, which is the nonparametric maximum likelihood estimator, is the preferred method. Software options are discussed: The reverse KM can be calculated using software for the KM estimator. The JMP and SAS (SAS Institute, Cary, NC) and Minitab (Minitab, Inc, State College, PA), software packages calculate the reverse KM directly using their Turnbull estimator routines., Conclusion: The reverse KM estimator is recommended for estimation of the distribution function and population percentiles in preference to commonly used methods such as substituting LOD/2 or LOD/ radical2 for values below the LOD, assuming a known parametric distribution, or using imputation to replace the left-censored values.

As part of the University of Michigan Dioxin Exposure Study, soil samples were collected from 766 residential properties near the Tittabawassee River between Midland and Saginaw; near the Dow Chemical Facility in Midland; and, for comparison, in the other areas of Midland and Saginaw Counties and in Jackson and Calhoun Counties, all located in the state of Michigan, USA. A total of 2,081 soil samples were analyzed for 17 polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). In order to better understand the distribution and sources of the PCDD/F congeners in the study area, hierarchical cluster analysis (HCA) was used to statistically group samples with similar congener patterns. The analysis yielded a total of 13 clusters, including: 3 clusters among the soils impacted by contamination present in the Tittabawassee River sediments, a cluster comprised mainly of samples collected within the depositional area of the Dow incinerator complex, a small cluster of samples with elevated 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TCDD), and several clusters exhibiting background patterns. The clusters related to the Tittabawassee River floodplain contamination all contained elevated PCDF levels and were differentiated from one another primarily by their relative concentrations of higher-chlorinated PCDDs, a difference likely related to both extent and timing of impacts from Tittabawassee sediments. The background clusters appear to be related to combustion processes and are differentiated, in part, by their relative fractions of TCDD. Thus, HCA was useful for identifying congener profile characteristics in both contaminated and background soil samples.

Background: In 2005, the World Health Organization (WHO) - International Programme on Chemical Safety reevaluated the toxic equivalency factors (TEFs) for dioxin-like compounds and made changes that affect the calculation of the total toxic equivalent (TEQ). The impact of these changes on the TEQs for human blood and abiotic matrices such as soil and household dust has not been widely assessed or reported., Methods and Results: Using a major exposure study which examined blood, household dust, and soil levels of dioxin-like compounds in several regions of Michigan, we found the mean total TEQ was significantly reduced by 26%, 12% and 14% for serum, household dust, and soil, respectively, when the TEQ was based on the 2005 TEFs compared to the 1998 TEFs. The decrease in the serum total TEQ was largely due to the down-weighting of the TEFs for the majority of mono-ortho PCBs. In contrast, the decrease in the soil total TEQ was mostly due to the down-weighting of the TEF for 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) (1998 TEF=0.5, 2005 TEF=0.3). For household dust, the decrease in total TEQ was not due to any single TEF but was due to small changes in a number of compounds. There was a dramatic decrease (-88%) in the mean and 95th percentile for mono-ortho PCB TEQ due to the 2005 TEFs., Discussion: These findings suggest that comparisons between studies based on the TEQ-WHO(98) and TEQ-WHO(05) may need to consider an appropriate conversion factor to assure comparability. Furthermore, the changes in TEFs may have impact in locations where regulations of soil contamination are triggered by specific TEQ levels.

Background: We conducted a population-based human exposure study in response to concerns among the population of Midland and Saginaw counties, Michigan, that discharges by the Dow Chemical Company of dioxin-like compounds into the nearby river and air had led to an increase in residents' body burdens of polychlorinated dibenzofurans (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs), here collectively referred to as "dioxins.", Objectives: We sought to identify factors that explained variation in serum dioxin concentrations among the residents of Midland and Saginaw counties. Exposures to dioxins in soil, river sediments, household dust, historic emissions, and contaminated fish and game were of primary interest., Methods: We studied 946 people in four populations in the contaminated area and in a referent population, by interview and by collection of serum, household dust, and residential soil. Linear regression was used to identify factors associated with serum dioxins., Results: Demographic factors explained a large proportion of variation in serum dioxin concentrations. Historic exposures before 1980, including living in the Midland/Saginaw area, hunting and fishing in the contaminated areas, and working at Dow, contributed to serum dioxin levels. Exposures since 1980 in Midland and Saginaw counties contributed little to serum dioxins., Conclusions: This study provides valuable insights into the relationships between serum dioxins and environmental factors, age, sex, body mass index, smoking, and breast-feeding. These factors together explain a substantial proportion of the variation in serum dioxin concentrations in the general population. Historic exposures to environmental contamination appeared to be of greater importance than recent exposures for dioxins.

Background: The University of Michigan Dioxin Exposure Study was undertaken to address concerns that the discharge of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo furans (PCDFs) from the Dow Chemical Company in the Midland, Michigan, area had resulted in contamination of soils in the Tittabawassee River floodplain and the city of Midland, leading to an increase in residents' body burdens of these compounds., Objective: In this article we present descriptive statistics from the resident survey and sampling of human serum, household dust, and soil and compare them with other published values., Methods: From a multistage random sample of populations in four areas of Midland and Saginaw counties and from a distant referent population, we interviewed 946 adults, who also donated blood for analysis of PCDDs, PCDFs, and polychlorinated biphenyls (PCBs). Samples of household dust and house perimeter soil were collected from consenting subjects who owned their property., Results: All five study populations were comparable in age, race, sex, and length of residence in their current home. Regional differences existed in employment history, personal contact with contaminated soils, and consumption of fish and game from contaminated areas. Median soil concentrations were significantly increased around homes in the Tittabawassee River floodplain (11.4 ppt) and within the city of Midland (58.2 ppt) compared with the referent population (3.6 ppt). Median serum toxic equivalencies were significantly increased in people who lived in the floodplain (23.2 ppt) compared with the referent population (18.5 ppt)., Conclusions: Differences in serum dioxin concentrations among the populations were small but statistically significant. Regression modeling is needed to identify whether the serum concentrations of PCDDs, PCDFs, and PCBs are associated with contaminated soils, household dust, and other factors.

Background: The University of Michigan Dioxin Exposure Study (UMDES) was undertaken in response to concerns that the discharge of dioxin-like compounds from the Dow Chemical Company facilities in Midland, Michigan, resulted in contamination of soils in the Tittabawassee River floodplain and areas of the city of Midland, leading to an increase in residents' body burdens of polychlorinated dibenzodioxins and polychlorinated dibenzofurans., Objectives: The UMDES is a hypothesis-driven study designed to answer important questions about human exposure to dioxins in the environment of Midland, where the Dow Chemical Company has operated for > 100 years, and in neighboring Saginaw, Michigan. In addition, the UMDES includes a referent population from an area of Michigan in which there are no unusual sources of dioxin exposure and from which inferences regarding the general Michigan population can be derived. A central goal of the study is to determine which factors explain variation in serum dioxin levels and to quantify how much variation each factor explains., Conclusions: In this article we describe the study design and methods for a large population-based study of dioxin contamination and its relationship to blood dioxin levels. The study collected questionnaire, blood, dust, and soil samples on 731 people. This study provides a foundation for understanding the exposure pathways by which dioxins in soils, sediments, fish and game, and homegrown produce lead to increased body burdens of these compounds.