Understanding disparities in emergency department visits for asthma

Asthma is the most common chronic disorder in childhood, affecting an estimated 6.2 million children under 18 years (1). The purpose of this study was to look at individual- and community-level characteristics simultaneously to examine and explain the factors that contribute to the use of emergency department services by children 18 years old or less and to determine if there was an association between air quality and ED visits in the same population, from 2005-2007 in Houston/Harris County. Data were collected from the Houston Safety Net Hospital Emergency Department Use Study and the 2000 US Census. Bivariate and multivariate logistic regression models and mixed effects models were used to analyze data that was collected during the study period.^ There were 704,902 ED visits made by children 18 and younger, who were living in Houston from January 1, 2005 to December 31, 2007. Of those, 19,098 had a primary discharge diagnosis of asthma. Asthma ED visits varied by season, with proportions of ED visits for asthma highest from September-December. African-American children were 2.6 (95% CI, 2.43-2.66) times more likely to have an ED visit for asthma compared to White children. Poverty, single parent headed households, and younger age all a greater likelihood of having gone to the ED for asthma treatment. Compared to Whites living in lightly-monitored pollution areas, African-Americans and Hispanics living in heavily monitored areas were 1.15 (95% CI, 1.04-1.28) times more likely to have an ED visit for asthma.^ Race and poverty seem to account for a large portion of the disparities in ED use found among children. This was true even after accounting for multiple individual- and community-level variables. These results suggest that racial disparities in asthma continue to pose risks for African American children, and they point to the need for additional research into potential explanations and remedies. Programs to reduce inappropriate ED use must be sensitive to an array of complex socioeconomic issues within minority and income populations. ^

Adherence to medication regimen among children with persistent asthma in Houston, Texas

An estimated 5.6 million children under the age of 18 suffer from asthma in the United States making asthma one of the most common chronic diseases in children. Because of the nature of the disease, the treatment regimen necessary to manage asthma has considerably changed as new drugs are developed and improved. The complexity of the treatment regimen recommended by the physician, however, has been linked with problems in adherence. Accordingly, the purpose of this cross-sectional study is to determine the prevalence of adherence to medication regimens among children between 9 to 15 years of age with physician-diagnosed asthma in Houston, Texas. The study used a set of data from a sample of children who participated in a pilot, panel asthma study to investigate the association between exposure to oxygenated air toxics and asthma health outcomes, conducted between 2002 and 2003. Data on daily intake of medication and onset of asthma-related symptoms were collected for each child per 10-day sampling period. Information was gathered through telephone or personal interviews for the 28 study participants who completed the study. The prevalence of adherence was calculated based on the number of times the participant reported taking his or her maintenance medication. The Fisher's Exact test and the Student's t-test were used to compare the level of adherence between the first and the last sampling cycle (Cycle 1 and Cycle 4) among the study participants by age, gender, and ethnicity. ^

ALLERGEN SENSITIZATION AND IMMUNOMODULATION BY SYNTHETIC LIGANDS, PUL-042, IN AN ALLERGEN-INDUCED ASTHMA MURINE MODEL

Allergen-induced asthma is the leading form of asthma and a chronic condition worldwide. Common allergens are known to contribute to the pathogenesis of this disease. Murine models of allergic asthma have mostly used an intraperitoneal route of sensitization (not airway) to study this disease. Allergic asthma pathophysiology involves the activation of TH2-specific cells, which triggers production of IgE antibodies, the up-regulation of TH2-specific cytokines (i.e. IL-4, IL-5, IL-9 and IL-13), increased airway eosinophilia, and mucin hypersecretion. Although there are several therapeutics currently treating asthmatic patients, some of these treatments can result in drug tolerance and may be linked to increased mortality. CpG oligodeoxynucleotides (ODNs) is a synthetic ligand that targets Toll-like Receptor (TLR) 9. It has been evaluated as a therapeutic agent for the treatment of cancer, infectious diseases, and for treating allergy and asthma. PUL-042 is also a synthetic TLR ligand and is composed of two agonists against TLR2/6 heterodimer and TLR9. Previous studies have evaluated PUL-042 for its ability to confer resistance against bacterial and viral lung infection. These findings, combined with studies performed using CpG ODNs, led to speculation that PUL-042 dampens the immune response in allergen-induced asthma. My thesis research investigated airway route sensitization and airway delivery of PUL-042 to evaluate its effects in reducing an allergen-induced asthma phenotype in a murine model. The results of this study contribute to the foundation for future investigations to evaluate the efficacy of PUL-042 as a novel therapy in allergic-asthma disease.