Is depression associated with insulin resistance? A systematic review

Studies suggest that depression affects glucose metabolism, and therefore is a risk factor for insulin resistance. The association between depression and insulin resistance has been investigated in a number of studies, but there is no agreement on the results. The objective of this study is to survey the epidemiological studies, identify the ones that measured the association of depression (as exposure) with insulin resistance (as outcome), and perform a systematic review to assess the reliability and strength of the association. For high quality reporting, and assessment, this systematic review used the outlined procedures, guidelines and recommendations for reviews in health care, suggested by the Centre for Reviews and Dissemination, along with recommendations from the STROBE group (Strengthening the Reporting of Observational Studies in Epidemiology). Ovid MEDLINE 1996 to April Week 1 2010, was used to identify the relevant epidemiological studies. To identify the most relevant set of articles for this systematic review, a set of inclusion and exclusion criteria were applied. Six studies that met the specific criteria were selected. Key information from identified studies was tabulated, and the methodological quality, internal and external validity, and the strength of the evidence of the selected studies were assessed. The result from the tabulated data of the reviewed studies indicates that the studies either did not apply a case definition for insulin resistance in their investigation, or did not state a specific value for the index used to define insulin resistance. The quality assessment of the reviewed studies indicates that to assess the association between insulin resistance and depression, specifying a case definition for insulin resistance is important. The case definition for insulin resistance is defined by the World Health Organization and the European Group for the Study of Insulin Resistance as the insulin sensitivity index of the lowest quartile or lowest decile of a general population, respectively. Three studies defined the percentile cut-off point for insulin resistance, but did not give the insulin sensitivity index value. In these cases, it is not possible to compare the results. Three other studies did not define the cut-off point for insulin resistance. In these cases, it is hard to confirm the existence of insulin resistance. In conclusion, to convincingly answer our question, future studies need to adopt a clear case definition, define a percentile cut-off point and reference population, and give value of the insulin resistance measure at the specified percentile.^

Goals, plans, and behavior changes: A relevant part of the post-treatment cancer experience

Background. Colorectal cancer (CRC) survivors have to manage treatment side effects, psychosocial issues, and co-morbidities, as well as modify their lifestyles to decrease risk of recurrence and prolong life. Identifying survivors’ goals and key factors that influence their goals will highlight the issues cancer survivors face post-treatment and the resources needed to help them engage in health-promoting behaviors.^ Objectives and methods. This dissertation examines the health-related goals of post-treatment CRC survivors using two studies: (1) a qualitative study to identify and describe the health goals of CRC survivors during the transition from active treatment to post-treatment survivorship and follow-up care; and (2) a cross-sectional survey to identify CRC survivors’ goals, and key factors that influence their goals.^ Results. (1) The 41 qualitative interviews indicated participants’ health-related goals were to be healthy, get back to normal, and not have a cancer recurrence. Most of the CRC survivors reported they maintained healthy behaviors, made healthy behavior changes, or had goals to change their behavior. Respondents were empowered to improve their health by maintaining follow-up care and regular health screenings, and many were managing treatment side effects in an effort to improve functional abilities. (2) The cross-sectional study found that CRC survivors’ most prevalent goals were related to healthy behaviors (i.e., eat a healthy diet and engage in physical activity), and cancer care or disease management (i.e., keep up with health screenings and monitor symptoms). Goals that survivors identified as important were similar to goals they perceived were important to their providers (i.e., goals related to cancer care, disease management). Certain goals were statistically associated with age, barriers to achieving goals, social support and health-related quality of life.^ Conclusions. CRC survivors have health-promoting goals post-treatment and are interested in making health behavior changes. Goals ranged from cancer care/surveillance and disease management to healthy lifestyle modifications. Patients may need help resolving or managing treatment side effects or co-morbidities prior to implementing health promoting behaviors. Healthcare providers’ recommendations may be a powerful resource to encourage survivors to engage in health-promoting behaviors. Self-management and goal setting support could be an appropriate strategy to assist patients with achieving their post-treatment health goals.^

The cost of publicly financed dental care in relation to community water fluoridation in Texas

Dental caries lead to children being less ready to learn and results in diminished productivity in the classroom. Tooth decay causes pain and infection, leading to impaired chewing, speech, and facial expression, in addition to a loss in self-esteem. There have been many studies supporting the safety and efficacy of community water fluoridation in reducing dental caries. Water fluoridation has been identified by the Centers for Disease Control and Prevention as one of 10 great public health achievements of the 20th century. The decline in the prevalence and severity of tooth decay in the United States during the past 60 years has been attributed largely to the increased use of fluoride; in particular, the widespread utilization of community water fluoridation. However, in the decades since fluoridation was first introduced, reductions in dental caries have declined, most likely due to the presence of other sources of fluoride. Questions have been raised regarding the need to continue to fluoridate community water supplies in the face of possible excessive exposure to fluoride. Nevertheless, dental caries continue to be a significant public health burden throughout the world, including the United States, especially among low-income and disadvantaged populations. Although many poor children receive their dental care through Medicaid, the percentage of Texas children with untreated dental caries continues to exceed the U.S. average and is well above Healthy People 2010 goals, even as state Medicaid expenditures continue to rise. The objective of this study is to determine the relationship between Medicaid dental expenditures and community water fluoridation levels in Texas counties. By examining this relationship, the cost-effectiveness of community water fluoridation in the Texas pediatric Medicaid beneficiary population, as measured by publicly financed dental care expenditures, may be ascertained.^

Probiotics and the prevention of necrotizing enterocolitis in preterm infants: A systematic review of the literature

Necrotizing enterocolitis is a common gastrointestinal disease associated with high mortality and morbidity among preterm infants. This was a systematic literature review that evaluated whether the administration of probiotic supplements is of benefit in the prevention of NEC. The search was narrowed to randomized clinical trials identified through The Cochrane Central Register of Controlled Trials, U.S. National Institute of Health clinical trials registry database, Pub Med and OVID MEDLINE databases. Inclusion criteria were: prospective, randomized clinical trials that administered probiotics as a preventive measure against NEC for infants of early gestational age (<35 wks) and/or low birth weight (<1500g), maintained NEC as the primary measured outcome, used Bell’s classification for NEC diagnosis with reports of stage 2 NEC or higher, and began probiotic administration within 10 days of life. Trials were excluded if participant enrollment was fewer than 100 infants, published before the year 2000, or probiotic supplementation was discontinued after less than seven consecutive days. Based on specific study characteristics, each resulting article was then judged by two authors for study quality. The search was further narrowed to studies of either high or moderate quality, which were then summarized in a set of tables based on study characteristics and results. From an initial set of 20 identified studies, five clinical trials met all criteria; each was discussed thoroughly based on trial limitations, strengths and comparisons to other included publications. Based on this review, the weight of evidence appears to support the use of probiotic supplementation in preterm infants as a preventive measure against NEC. Recommendations for future research were also provided.^

A computerized statistical framework for coalescent analysis

Coalescent theory represents the most significant progress in theoretical population genetics in the past three decades. The coalescent theory states that all genes or alleles in a given population are ultimately inherited from a single ancestor shared by all members of the population, known as the most recent common ancestor. It is now widely recognized as a cornerstone for rigorous statistical analyses of molecular data from population [1]. The scientists have developed a large number of coalescent models and methods[2,3,4,5,6], which are not only applied in coalescent analysis and process, but also in today’s population genetics and genome studies, even public health. The thesis aims at completing a statistical framework based on computers for coalescent analysis. This framework provides a large number of coalescent models and statistic methods to assist students and researchers in coalescent analysis, whose results are presented in various formats as texts, graphics and printed pages. In particular, it also supports to create new coalescent models and statistical methods. ^

Assessment of the effect on statistical power of regression model misspecification by using techniques of mathematical statistics and simulation study

Objectives. This paper seeks to assess the effect on statistical power of regression model misspecification in a variety of situations. ^ Methods and results. The effect of misspecification in regression can be approximated by evaluating the correlation between the correct specification and the misspecification of the outcome variable (Harris 2010).In this paper, three misspecified models (linear, categorical and fractional polynomial) were considered. In the first section, the mathematical method of calculating the correlation between correct and misspecified models with simple mathematical forms was derived and demonstrated. In the second section, data from the National Health and Nutrition Examination Survey (NHANES 2007-2008) were used to examine such correlations. Our study shows that comparing to linear or categorical models, the fractional polynomial models, with the higher correlations, provided a better approximation of the true relationship, which was illustrated by LOESS regression. In the third section, we present the results of simulation studies that demonstrate overall misspecification in regression can produce marked decreases in power with small sample sizes. However, the categorical model had greatest power, ranging from 0.877 to 0.936 depending on sample size and outcome variable used. The power of fractional polynomial model was close to that of linear model, which ranged from 0.69 to 0.83, and appeared to be affected by the increased degrees of freedom of this model.^ Conclusion. Correlations between alternative model specifications can be used to provide a good approximation of the effect on statistical power of misspecification when the sample size is large. When model specifications have known simple mathematical forms, such correlations can be calculated mathematically. Actual public health data from NHANES 2007-2008 were used as examples to demonstrate the situations with unknown or complex correct model specification. Simulation of power for misspecified models confirmed the results based on correlation methods but also illustrated the effect of model degrees of freedom on power.^

Understanding treatment-related symptoms, symptom management techniques, and symptom management self-efficacy in a sample of non-muscle invasive bladder cancer patients

The current literature available on bladder cancer symptom management from the perspective of the patients themselves is limited. There is also limited psychosocial research specific to bladder cancer patients and no previous studies have developed and validated measures for bladder cancer patients’ symptom management self-efficacy. The purpose of this study was to investigate non-muscle invasive bladder cancer patients’ health related quality of life through two main study objectives: (1) to describe the treatment related symptoms, reported effectiveness of symptom-management techniques, and the advice a sample of non-muscle invasive bladder cancer patients would convey to physicians and future patients; and (2) to evaluate Lepore’s symptom management self-efficacy measure on a sample of non-muscle invasive bladder cancer patients. Methods. A total of twelve (n=12) non-muscle invasive bladder cancer patients participated in an in-depth interview and a sample of 46 (n=4) non-muscle invasive bladder cancer patients participated in the symptom-management self-efficacy survey. Results. A total of five symptom categories emerged for the participants’ 59 reported symptoms. Four symptom management categories emerged out of the 71 reported techniques. A total of 62% of the participants’ treatment related symptom-management techniques were reported as effective in managing their treatment-related symptoms. Five advice categories emerged out of the in-depth interviews: service delivery; medical advice; physician-patient communication; encouragement; and no advice. An exploratory factor analysis indicated a single-factor structure for the total population and a multiple factor structure for three subgroups: all males, married males, and all married participants. Conclusion. These findings can inform physicians and patients of effective symptom-management techniques thus improving patients’ health-related quality of life. The advice these patients’ impart can improve service-delivery and patient education.^

Shigellosis in Hidalgo County, Texas 2005--2009: A descriptive study

Shigellosis is a communicable disease harbored primarily by humans. The low infective dose, no vaccine availability, and mild or asymptomatic nature of disease has prevented eradication of Shigella in the United States. In addition, the lack of water and sewage infrastructures which normally contribute to the spread of disease in developing countries, for the most part, is a non-issue in the U.S. making surveillance and risk factor identification important prevention and control measures utilized to reduce the incidence rates of Shigellosis.^ The purpose of this study was to describe the Shigellosis disease burden among the Hidalgo County, Texas population during the 2005-2009 study period and compare these findings with national data available. The potential identification and publication of a health disparity in the form of increased Shigellosis rates among Hidalgo County residents when compared to national rates, especially age-specific rates, are intended to generate public health attention and public health action that will address this issue.^ There were 1,007 confirmed Shigellosis cases reported in Hidalgo County, Texas. An overwhelming majority (79%) of the Shigellosis cases during this time frame occurred in children less than ten years of age. Over the age of 10 through the age of 39, females constituted the majority of cases. Age-specific rates for children four years of age and younger were compared to national rates. The rates for Hidalgo County were higher at 9.2 and 1.8 cases for every one case reported nationally in 2005 and 2006, respectively. The total crude rates of Shigellosis were also higher than the rates available from the Foodborne Diseases Active Surveillance Network (FoodNet) of CDC’s Emerging Infections Program from 2005-2009. As a result, compared to the FoodNet surveillance rates, Hidalgo County experienced above average rates of Shigellosis throughout the study period. The majority of cases were identified in young children under the age of ten.^ The information gathered in this analysis could be used to implement and monitor infection control measures such as hand washing education at facilities that tend to the groups identified at higher risk of infection. In addition, the higher burden of disease found in Hidalgo County requires further study to determine if there are factors associated with an increased risk of Shigellosis in this community and other border communities along the U.S.-Mexico border exist.^

Public service use by residents of Jackson Hinds Gardens before and after enrollment

Homelessness is associated with high use of public services such as health care and criminal justice services. Intervention designs to reverse homelessness have broadly fallen into two categories: either standard care which employs requisitely addressing the causes of homelessness, or housing first, which emphasizes provision of permanent housing without requisitely addressing the causes of homelessness. Multiple cities have recently commenced housing first interventions. Locally, Houston’s first housing first development is the Jackson Hinds Gardens project. The purpose of this study is to analyze the public service use of residents of housing first in Houston. Residents of Jackson Hinds Gardens who have been enrolled for at least 6 months were evaluated for public service use for an equal amount of time preceding and during their residence at Jackson Hinds. Resident interactions with county health services and criminal justice entities were determined by electronic database searches; these data were supplemented by life experience interview data. Service usage values pre- and post-enrollment at Jackson Hinds Gardens were compared by paired t-test analyses. We found that ER and inpatient usage decreased following enrollment in Jackson Hinds, although these reductions were not significant. In contrast, outpatient care and number of medications significantly increased following enrollment. These analyses inform on the effects of housing first in another major city, as well as informing the ethical considerations regarding housing first versus standard care. ^

Physical activity among breast and prostate cancer survivors: Barriers, facilitators and maintenance following the FRESH START trial

Research provides evidence of the positive health effects associated with regular physical activity participation in all populations. Activity may prove to be especially beneficial in those with chronic conditions such as cancer. However, the majority of cancer patients and survivors do not participate in the recommended amount of physical activity. The purpose of this dissertation was to identify factors associated with physical activity participation, describe how these factors change as result of a diet and exercise intervention, and to evaluate correlates of long term physical activity maintenance. ^ For this dissertation, I analyzed data from the FRESH START trial, a randomized, single-blind, phase II clinical trial focused on improving diet and physical activity among recently diagnosed breast and prostate cancer survivors. Analyses included both parametric and non-parametric statistical tests. Three separate studies were conducted, with sample sizes ranging from 400 to 486. ^ Common barriers to exercise, such as “no willpower,” “too busy,” and “I have pain,” were reported among breast and prostate cancer survivors; however, these barriers were not significantly associated with minutes of physical activity. Breast cancer survivors reported a greater number of total barriers to exercise as well as higher proportions reporting individual barriers, compared to prostate cancer survivors. Just less than half of participants reduced their total number of barriers to exercise from baseline to 1-year follow-up, and those who did reduce barriers reported greater increases in minutes of physical activity compared to those who reported no change in barriers to exercise. Participants in both the tailored and standardized intervention groups reported greater minutes of physical activity at 2-year follow-up compared to baseline. Overall, twelve percent of participants reached recommended levels of physical activity at both 1- and 2-year follow-up. Self-efficacy was positively associated with physical activity maintenance, and the number of total barriers to exercise was inversely associated with physical activity maintenance. ^ Results from this dissertation are novel and informative, and will help to guide future physical activity interventions among cancer survivors. Thoughtfully designed interventions may encourage greater participation in physical activity and ultimately improve overall quality of life in this population. ^

Campaign contributions to congressional candidates by the healthcare sector from 1990 to 2008

Stakeholder groups with special interests as donors to finance congressional campaigns have been a controversial issue in the United Sates. While previous studies concentrated on whether a connection existed between the campaign contributions provided by stakeholder groups and the voting behavior of congressional members, there is little evidence to show the trend of allocation of their campaign contributions to their favorite candidates during the elections. This issue has become increasingly important in the health sector since the health care reform bill was passed in early 2010.^ This study examined the long-term trend of campaign contributions offered by various top healthcare stakeholder groups to particular political parties (i.e. Democrat and Republican). The main focus of this paper was to observe and describe the financial donations provided by these healthcare stakeholder groups in the congressional election cycles from 1990 to 2008 in order to obtain an overview of their patterns of campaign contributions. Their contributing behaviors were characterized based on the campaign finance data collected by the Center for Responsive Politics (CRP). Specifically, I answered the questions: (1) to which political party did specific healthcare stakeholder groups give money and (2) what was the pattern of their campaign contributions from 1990 to 2008?^ The findings of my study revealed that the healthcare stakeholder groups had different political party preferences and partisanship orientations regarding the Democratic or Republican Party. These differences were obvious throughout the election cycles from 1990 to 2008 and their distinct patterns of financial contribution were evident across industries in the health sector as well. Among all the healthcare stakeholder groups in this study, physicians were the top contributors in the congressional election. The pharmaceutical industry was the only group where the majority of contribution funds were allocated to Republicans in every election period studied. This study found that no interest group has succeeded in electing the preferred congressional candidate by giving the majority of its financial support to the winning party in every election. Chiropractors, hospitals/nursing homes, and health services/HMOs performed better than other healthcare stakeholder groups by supporting the electoral winner 8 out of 9 election cycles.^

African American and Hispanic adolescent STI and pregnancy prevention: Whose responsibility is it, anyway?

This dissertation utilized quantitative and qualitative methods to examine the role of responsibility in the prevention of sexually transmitted infections (STIs) and pregnancy through condom use and other sexual behaviors among young adolescents. Data were analyzed across race and gender and three papers were developed. The quantitative portion used logistic regression to assess associations between personal responsibility, as well as other know correlates, and reported condom use and condom use intentions as a means of STI and pregnancy prevention among 445 inner-city, high school adolescents. Responsibility to prevent pregnancy by providing the condom was associated with condom use at last sex and consistent condom use. Responsibility to prevent acquiring a STI by using a condom was significantly associated with consistent condom use. No significant associations were found between responsibility and condom use intentions. ^ The qualitative section of the dissertation project involved conducting 28 in-depth interviews among 9th and 10th grade, African American and Hispanic students who attended a large urban school district in South Central Texas. Perceptions of responsibility for preventing STIs and unintended pregnancy, as well as for condom use, were explored. Male and female adolescents expressed joint responsibility to prevent a STI or pregnancy. Perceptions of responsibility for providing and using the condoms were mixed. Despite the indication of both partners, mostly all participants implied that females, more so than the males, had the final responsibility to prevent contracting a STI, a pregnancy, to provide a condom, and to make sure a condom was used. Participants expressed the role of parents' involvement for preventing these outcomes as well as the need for more sexual health education and access to preventative methods. ^ The last section of this dissertation involved qualitative inquiry to ascertain perceptions of reasons why adolescents engage in anal and oral (non-coital) sex. Pleasure-seeking and giving as well social influence and pressure were described as the main reasons why teenagers have non-coital sex. Other reasons included conveniences of participating in these behaviors such as ease of performing oral sex and anal sex as a convenient alternative to vaginal sex. Sexual inexperience was an indicator for why anal sex occurs. Many of the reasons involved misperceptions and adolescents who practice these sexual behaviors place themselves at-risk for contracting a STI. ^ This dissertation increased the current knowledge base about adolescent sexual responsibility and non-coital behaviors. Future studies should explore perceptions of responsibility and actual sexual activity practices among adolescents to reduce the burden of STIs and pregnancy as well as help public health professionals develop programs for adolescent populations, schools, and communities where these issues persist.^

Targeted immunization to protect infants against pertussis in the United States

Pertussis is an infectious disease caused by the bacteria Bordetella pertussis, and is associated with a serious respiratory infection, a prolonged cough, and can require hospitalization. A vaccine for adolescents and adults has been available since 2005. This paper examines one recommended immunization strategy to prevent pertussis among infants, called “cocooning.” The strategy focuses on creating immunity among adult caregivers so they serve as a protective cocoon to the newborns, who are too young to be vaccinated. This paper looks at relevant studies summarizing implementation of cocooning strategies and addresses the question – Does the research literature support the view of using cocooning as an effective strategy to prevent pertussis in infants? After exclusions, 8 studies remained for synthesis. The evidence shows that cocooning is complex strategy and the evidence is mixed when it comes to ensuring an increase in immunization of caregivers. ^

Ascertainment, meta-analysis and reporting of adverse reactions in clinical trials of antibiotics

The ascertainment and analysis of adverse reactions to investigational agents presents a significant challenge because of the infrequency of these events, their subjective nature and the low priority of safety evaluations in many clinical trials. A one year review of antibiotic trials published in medical journals demonstrates the lack of standards in identifying and reporting these potentially fatal conditions. This review also illustrates the low probability of observing and detecting rare events in typical clinical trials which include fewer than 300 subjects. Uniform standards for ascertainment and reporting are suggested which include operational definitions of study subjects. Meta-analysis of selected antibiotic trials using multivariate regression analysis indicates that meaningful conclusions may be drawn from data from multiple studies which are pooled in a scientifically rigorous manner. ^

Community diagnosis: A working tool for developing culturally appropriate diarrhea intervention programs

Most studies related to diarrhea have been focused narrowly on the etiological and pathophysiological factors involved in inducing the disease. Such studies have often failed to consider other facets contributing to and possibly prolonging the problem, namely: socio-economic conditions, educational opportunities and attainments, cultural characteristics and beliefs, and the political administration and its commitment towards fulfilling its moral and ethical obligations in responding to and fostering human development.^ This study utilized the diagnostic approach of the PRECEDE model. The acronym stands for the predisposing reinforcing, and enabling constructs in educational diagnosis and evaluation. The constituents of this model were identified by utilizing participant observation field methods, traditionally applied by ethnographers to collect data describing the multiple facets of a culture, and linguistic anthropology used to capture and define characteristic semantics and viewpoints. The household study sample was randomly selected from a defined list of households known to have at least one child less than five years of age. An open-ended questionnaire format was used to interview the 115 mothers in the selected households sample.^ Kalama, the study community, is characteristically an agricultural village, situated in the Governorate of Kaliobia and located approximately 25 Km (about 15.5 miles) from the capital, Cairo, Egypt. The 1986 census indicates a population size of 13,328 people in 4,818 households. There were 65 deaths occurring among children less than five years in 1986. The causes of death were primarily related to diarrhea, followed by upper respiratory infections, congenital anomalies and birth injuries.^ This study outlines (a) practices related to the management of diarrhea, including the administration of foods and drinks during such episodes; (b) influences of governmental policies; and (c) recommended strategies for overcoming barriers and promoting effective diarrhea intervention programs. ^