Modeling survival and the development of second primary tumors among Hodgkin's disease patients

Hodgkin's disease (HD) is a cancer of the lymphatic system. Survivors of HD face varieties of consequent adverse effects, in which secondary primary tumors (SPT) is one of the most serious consequences. This dissertation is aimed to model time-to-SPT in the presence of death and HD relapses during follow-up.^ The model is designed to handle a mixture phenomenon of SPT and the influence of death. Relapses of HD are adjusted as a covariate. Proportional hazards framework is used to define SPT intensity function, which includes an exponential term to estimate explanatory variables. Death as a competing risk is considered according to different scenarios, depending on which terminal event comes first. Newton-Raphson method is used to estimate the parameter estimates in the end.^ The proposed method is applied to a real data set containing a group of HD patients. Several risk factors for the development of SPT are identified and the findings are noteworthy in the development of healthcare guidelines that may lead to the early detection or prevention of SPT.^

Malaria prevention in Kenyan women of childbearing age

The objective of this program is to reduce malaria incidence in Kenya. Malaria poses a large public health challenge in Kenya, and although public health efforts have traditionally been focused on treatment of infected patients, due to increased drug resistance and lack of drug-adherence, prevention strategies are needed. This program targets Kenyan women, the likely caretakers in the home, and promotes malaria prevention behaviors through health education. ^ A planning group will be assembled and a needs assessment will be performed, verifying risk factors and conditions associated with malaria, as well as personal and external determinants. Behavioral and environmental outcomes will be determined, and performance objectives for each outcome will be established. Matrices of change objectives will be created, and detailed methods and strategies will be linked to each change objective. Program elements include media, education, and incentives. All materials used in this program will be subjected to pre-test to ensure cultural relevance and fidelity. Matrices of change objectives will be created for program adopters and implementers, as well as correlating methods and strategies associated with each change objective. Performance objectives will also be compiled for program maintainers. A program evaluation plan will follow "Pre-Post Comparison Group" design. Outcome evaluation and process evaluation will be conducted. The sample population will be screened based on age and gender so as to maintain comparability to the target population. Measurements will be taken before the program to establish baseline, directly following the program to determine short-term effects, and three months after the program is completed to determine long-term effects. ^ One limitation of this program is selection bias, due to the nature of quasi-experimental studies. Thorough screening prior to sample selection will minimize selection bias and ensure group homogeneity. Another limitation is attrition, and this will be minimized where possible through the use of incentives. In cases where loss to follow-up is not avoidable, such as death or natural disasters, the attrition effect will be estimated using structural equation modeling after reviewing the sample size, differential attrition and total attrition. ^ This intervention is based heavily on health promotion theories, but it is important to remember that in the field, the program plan will likely include only the necessary practical strategies. The target population, Kenyan women of childbearing age, will be significant in decreasing the malaria disease burden in Kenya.^

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.^

Prevalence of gastro esophageal reflux disease following the Montreal Consensus and its association with Helicobacter pylori infection and obesity in a random sample of adults of Ciudad Juarez, Mexico, 2004.

Gastroesophageal reflux disease is a common condition affecting 25 to 40% of the population and causes significant morbidity in the U.S., accounting for at least 9 million office visits to physicians with estimated annual costs of $10 billion. Previous research has not clearly established whether infection with Helicobacter pylori, a known cause of peptic ulcer, atrophic gastritis and non cardia adenocarcinoma of the stomach, is associated with gastroesophageal reflux disease. This study is a secondary analysis of data collected in a cross-sectional study of a random sample of adult residents of Ciudad Juarez, Mexico, that was conducted in 2004 (Prevalence and Determinants of Chronic Atrophic Gastritis Study or CAG study, Dr. Victor M. Cardenas, Principal Investigator). In this study, the presence of gastroesophageal reflux disease was based on responses to the previously validated Spanish Language Dyspepsia Questionnaire. Responses to this questionnaire indicating the presence of gastroesophageal reflux symptoms and disease were compared with the presence of H. pylori infection as measured by culture, histology and rapid urease test, and with findings of upper endoscopy (i.e., hiatus hernia and erosive and atrophic esophagitis). The prevalence ratio was calculated using bivariate, stratified and multivariate negative binomial logistic regression analyses in order to assess the relation between active H. pylori infection and the prevalence of gastroesophageal reflux typical syndrome and disease, while controlling for known risk factors of gastroesophageal reflux disease such as obesity. In a random sample of 174 adults 48 (27.6%) of the study participants had typical reflux syndrome and only 5% (or 9/174) had gastroesophageal reflux disease per se according to the Montreal consensus, which defines reflux syndromes and disease based on whether the symptoms are perceived as troublesome by the subject. There was no association between H. pylori infection and typical reflux syndrome or gastroesophageal reflux disease. However, we found that in this Northern Mexican population, there was a moderate association (Prevalence Ratio=2.5; 95% CI=1.3, 4.7) between obesity (≥30 kg/m2) and typical reflux syndrome. Management and prevention of obesity will significantly curb the growing numbers of persons affected by gastroesophageal reflux symptoms and disease in Northern Mexico. ^

Disease risk factors and humoral antibody response to periodontal-associated pathogens: A model to evaluate periodontal disease in older adults

Periodontal diseases (PD) are infectious, inflammatory, and tissue destructive events which affect the periodontal ligament that surround and support the teeth. Periodontal diseases are the major cause of tooth loss after age 35, with gingivitis and periodontitis affecting 75% of the adult population. A select group of bacterial organisms are associated with periodontal pathogenesis. There is a direct association between oral hygiene and prevention of PD. The importance of genetic differences and host immune response capabilities in determining host, susceptibility or resistance to PD has not been established. This study examined the risk factors and serum (humoral) immune response to periodontal diseased-associated pathogens in a 55 to 80+ year old South Texas study sample with PD. This study sample was described by: age, sex, ethnicity, the socioeconomic factors marital status, income and occupation, IgG, IgA, IgM immunoglobulin status, and the autoimmune response markers rheumatoid factor (RF) and antinuclear antibody (ANA). These variables were used to determine the risk factors associated with development of PD. Serum IgG, IgA, IgM antibodies to bacterial antigens provided evidence for disease exposure.^ A causal model for PD was constructed from associations for risk factors (ethnicity, marital status, income, and occupation) with dental exam and periodontitis. The multiple correlation between PD and ethnicity, income and dental exam was significant. Hispanics of low income were least likely to have had a dental exam in the last year and most likely to have PD. The etiologic agents for PD, as evidenced by elevated humoral antibody responses, were the Gram negative microorganisms Bacteroides gingivalis, serotypes FDC381 and SUNYaBA7A1-28, and Wolinella recta. Recommendation for a PD prevention and control program are provided. ^

Systematic review of current trends of cardiovascular disease (CVD) and association between health insurance coverage and CVD mortality among women aged 60--65 in Texas in 2000--2011

Cardiovascular disease (CVD) is highly preventable, yet it is a leading cause of death among women in Texas. The primary goals of this research were to examine past and current trends of CVD, as well as identify whether there is an association between the insurance coverage and mortality from CVD among women aged 60–65 in Texas between 2000 and 2011. ^ The systematic review of the research is based on the guidelines and recommendations set by the Centre for Reviews and Dissemination for conducting reviews in health care. Over 47 citations of peer-reviewed articles from Ovid MEDLINE and PubMed databases and five websites were identified, of which 7 studies met inclusion criteria for the first systematic review to examine the trends of CVD in Texas. Ten citations of peer-reviewed articles from Ovid MEDLINE and PubMed databases and five web sites were reviewed for the second systematic review (to study the association between insurance coverage and cardiovascular health among Texas women 60–64 years of age), of which 3 studies met inclusion criteria and were included in the research. The results of the study highlighted key gaps in the existing literature and important areas for the further research, as well as determined directions for future public health CVD prevention programs in Texas. ^ Based on the conducted research, the major determinants of premature mortality among women attributed to cardiovascular disease are based on individual level characteristics, more specifically sex, age, race/ethnicity, and education. The results indicate that African American and non-Hispanic white women are more likely to have higher CVD mortality rates than Hispanic women due to higher prevalence of cardiac risk factors. The data also shows higher levels of mortality from CVD in the southeastern United States, with Texas ranking as the third state with the highest prevalence of CVD among women. According to the Texas Department of State Health Services, there are approximately 56,000 deaths caused by CVD annually in Texas, which represents about one death every ten minutes. Coronary artery disease and stroke were the causes of 31.2 percent of all female deaths in Texas in 2009, meaning that approximately 68 women die from any form of cardiac disease in Texas each day. ^ The data of the reviewed studies indicate that women' lack of health insurance was significantly associated with a higher prevalence of cardiovascular disease. The uninsured women were more likely to be unaware of their risk factors and more likely to have undiagnosed diabetes—a co-morbidity factor of CVD. One of the studies also reports strong correlation between state rates of uninsured and lower rates of preventive care. Given these strong correlations, those who were chronically uninsured were at a higher risk of mortality than the insured, due to prolonged periods of time without basic access to preventive and medical care. ^ Suggested recommendations to decrease CVD mortality rates in Texas are consistent with the existing literature and include state policy development that addresses elimination of health disparities, consideration of potential benefits of universal health coverage by the legislative policymakers, and maintenance of solid partnerships between public health agencies and hospitals to educate on, diagnose, and treat CVD among the female population in Texas. ^

Influenza vaccination as a primary or secondary prevention for cardiovascular diseases: A systematic review of the literature

Background: Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality worldwide. CVD mainly comprise of coronary heart disease and stroke and were ranked first and fourth respectively amongst leading causes of death in the United States. Influenza (flu) causes annual outbreaks and pandemics and is increasingly recognized as an important trigger for acute coronary syndromes and stroke. Influenza vaccination is an inexpensive and effective strategy for prevention of influenza related complications in high risk individuals. Though it is recommended for all CVD patients, Influenza vaccine is still used at suboptimal levels in these patients owing to prevailing controversy related to its effectiveness in preventing CVD. This review was undertaken to critically assess the effectiveness of influenza vaccination as a primary or secondary prevention method for CVD. ^ Methods: A systematic review was conducted using electronic databases OVID MEDLINE, PUBMED (National Library of Medicine), EMBASE, GOOGLE SCHOLAR and TRIP (Turning Research into Practice). The study search was limited to peer-reviewed articles published in English language from January 1970 through May 2012. The case control studies, cohort studies and randomized controlled trials related to influenza vaccination and CVD, with data on at least one of the outcomes were identified. In the review, only population-based epidemiologic studies in all ethnic groups and of either sex and with age limitation of 30 yrs or above, with clinical CVD outcomes of interest were included. ^ Results: Of the 16 studies (8 case control studies, 6 cohort studies and 2 randomized controlled trials) that met the inclusion criteria, 14 studies reported that there was a significant benefit in u influenza vaccination as primary or secondary prevention method for preventing new cardiovascular events. In contrary to the above findings, two studies mentioned that there was no significant benefit of vaccination in CVD prevention. ^ Conclusion: The available body of evidence in the review elucidates that vaccination against influenza is associated with reduction in the risk of new CVD events, hospitalization for coronary heart disease and stroke and as well as the risk of death. The study findings disclose that the influenza vaccination is very effective in CVD prevention and should be encouraged for the high risk population. However, larger and more future studies like randomized control trials are needed to further evaluate and confirm these findings. ^