Asthma Disparities Research Articles

Genetic variants of GSNOR and ADRB2 influence response to albuterol in African‐American children with severe asthma

African Americans are disproportionately affected by asthma. Social and economic factors play a role in this disparity, but there is evidence that genetic factors may also influence the development of asthma and response to therapy in African American children. Our hypothesis is that variations in asthma related genes contribute to the observed asthma disparities by influencing the response to asthma-specific therapy. In order to test this hypothesis, we characterized the clinical response to asthma-specific therapy in 107 African American children who presented to the emergency room in status asthmaticus, with a primary outcome indicator of length of time on continuous albuterol. Single locus analysis indicated that genotype variation in glutathione-dependent S-nitrosoglutathione reductase (GSNOR) is associated with a decreased response to asthma treatment in African American children. A post hoc multi-locus analysis revealed that a combination of four single nucleotide polymorphisms (SNPs) within GSNOR, adrenergic receptor beta 2, and carbamoyl phosphate synthetase-1 give a 70% predictive value for lack of response to therapy. This predictive model needs replication in other cohorts of patients with asthma, but suggests gene-gene interactions may have greater significance than that identified with single variants. Our findings also suggest that genetic variants may contribute to the observed population disparities in asthma.

Asthma disparities in urban environments

Asthma disparities in urban environments

Disparities in childhood asthma hospitalizations: A spatial analysis of contextual effects

Transportation and health inequities have been subjects of study by scholars from various disciplines, but the linkages among traffic exposure, race, class, and asthma is neither sufficient nor conclusive. Previous studies suggest that the relationships are multifaceted and geographically specific. We investigate neighborhood social and transportation impacts on childhood asthma disparities in Tarrant County, Texas, using geographical information systems. Results reveal distinctive socio-demographic characteristics of the patients; clear spatial patterns of neighborhoods with and without asthma hospitalizations; and significant contextual effects of traffic density, race, and class on neighborhood childhood asthma hospitalizations. The findings generally support the notion of contextual effects.

Asthma and ethnic minorities: socioeconomic status and beyond.

We aim to discuss current insights into our understanding of the mechanisms by which socioeconomic status influences the prevalence and severity of asthma in ethnic minorities. In addition, we review potential risk factors for ethnic disparities in asthma that are not mediated by socioeconomic status. Exposures and factors correlated with ethnicity through socioeconomic status (e.g. indoor and outdoor air quality, smoke exposure, and access to healthcare) are likely to explain a significant proportion of the observed ethnic differences in asthma morbidity. However, other factors correlated with ethnicity (e.g. genetic variation) can impact ethnic disparities in asthma independently of and/or interacting with socioeconomic status-related factors. Socioeconomic status is a rough marker of a variety of environmental/behavioral exposures and a very important determinant of differences in asthma prevalence and severity among ethnic minorities in the United States. However, socioeconomic status is unlikely to be the sole explanation for ethnic disparities in asthma, which may also be due to differences in genetic variation and gene-by-environment interactions among ethnic groups.

The Impact of Geographic Variation on Racial Disparities in Asthma: Controller Medication Use among Medicaid Asthmatics in Four Large States

The Impact of Geographic Variation on Racial Disparities in Asthma: Controller Medication Use among Medicaid Asthmatics in Four Large States

The burden of asthma in the Chicago community fifteen years after the availability of national asthma guidelines: The design and initial results from the CHIRAH study

Since the early 1990s, asthma burden has been recognized as a national public health concern in the United States [1]. The asthma burden has disproportionately affected persons of certain racial/ethnic backgrounds, principally African Americans [2] and those persons living in urban environments [3,4]. Concern about the growing problem of asthma has led to a number of national, state, and local efforts towards improving asthma outcomes and control [5,6,7,8]. No national effort toward asthma control has been more celebrated than the implementation of the National Heart, Lung and Blood Institute's National Asthma Education and Prevention Program (NAEPP). Initiated in 1989, to a large extent in response to the public's concern about the increased asthma prevalence and burden, the NAEPP set its first programmatic effort to the establishment of guidelines to improve asthma care [9]. Since the initial release of these guidelines in 1991, hundreds of thousands of copies have been distributed [10] and there have been countless efforts directed toward moving these guidelines into practice including continuing medical education (CME) programs, disease management programs, clinical performance measures, and research efforts. The NAEPP continues efforts in the establishment of national guidelines through a series of updates to the original guidelines, including the recent release of a major update in November 2007 [11,12]. While there continues to be numerous reports of progress of local implementation and health plan efforts, these reports have focused on changes in asthma processes of care or on outcomes limited primarily to health care utilization among selected, mostly health plan or practice-based samples. To date, there is a rather modest literature on community-wide population-based status of asthma burden and quality of care. The Chicago Initiative to Raise Asthma Health Equity (CHIRAH) is one of the NHLBI Centers of Excellence in Reducing Asthma Disparities. The core activity of the CHIRAH has been to conduct a community-based cohort study designed to characterize those factors that are contributing to racial/ethnic disparities with the purpose of identifying mutable factors that may provide the basis for new intervention strategies to eliminate these disparities. The CHIRAH project therefore provides a unique opportunity to report on a population-based understanding of the burden of asthma in a large urban environment known to have one of the highest asthma mortality rates in the US [13]. The purpose of this report is to examine the overall burden of asthma morbidity and treatment as seen from the perspective of this community-based study.

Eliminating asthma disparities: is there evidence of progress?

In spite of numerous efforts, asthma rates in the United States remain historically high and disparities persist among low-income and minority populations. This review assesses the current status of asthma inequities from the perspective of disease development, progression, and outcomes. Recent findings highlight the complex and multifactorial nature of asthma. There is a clear line of emerging evidence suggestive of important hierarchical relationships between the predisposed or affected individual and his or her intrapersonal life, familial relationships, social networks, and broader community. Approaches in basic, clinical, and translational asthma research must be modified to account for the social construct of race and to detangle complex interactions of contributing factors at and across the individual and community level. However, there are a number of obvious opportunities to dramatically reduce asthma disparities at hand.

Maternal Mental Health and Childhood Asthma among Puerto Rican Youth: The Role of Prenatal Smoking

Rationale. Childhood asthma is a major public health problem, with mainland and island Puerto Rican children having the highest asthma rates of any ethnic group in the United States. Objectives. To examine the relationship between maternal mental health problems, prenatal smoking, and risk of asthma among children in Puerto Rico and the Bronx, New York. Methods. A cross-sectional community-based study was conducted in the South Bronx in New York City and the San Juan Standard Metropolitan Area in Puerto Rico. Participants were Puerto Rican children 5 to 13 years of age and their adult caretakers with probability samples of children 5 to 13 years of age and their caregivers drawn at two sites: the South Bronx in New York City (n = 1,135) and San Juan and Caguas, Puerto Rico (n = 1,351). Measurements. Self-reported maternal mental health, prenatal smoking, and rates of childhood asthma. Results. Maternal mental health problems were associated with significantly higher levels of prenatal smoking, compared with that among women without mental health problems (p < 0.0001). Both maternal mental health problems and prenatal smoking appear to make a contribution to increased odds of asthma among youth. After adjusting for prenatal smoking, the relationship between maternal mental health problems and childhood asthma was no longer statistically significant. Conclusions. Previous research suggests children of Puerto Rican descent are especially vulnerable to asthma. Our results suggest that maternal mental health problems and prenatal smoking are both associated with increased odds of asthma among Puerto Rican youth and that prenatal smoking may partly explain the observed relationship between maternal psychopathology and childhood asthma. Future longitudinal and geographically diverse epidemiological studies may help to identify the role of both maternal mental health problems and prenatal smoking in the health disparities in childhood asthma.

Hospital readmissions for childhood asthma: the role of individual and neighborhood factors.

This study used a Cox proportional hazards model to determine whether neighborhood characteristics are associated with risk of readmission for childhood asthma independently of individual characteristics. Rhode Island Hospital Discharge Data from 2001 to 2005 were used to identify children younger than 19 years of age at the time of the index (i.e., first) asthma admission, defined as a primary diagnosis of asthma or a primary diagnosis of respiratory illness with a secondary or tertiary diagnosis of asthma (n=2,919). Hazard ratios of repeat hospitalizations for childhood asthma from 2001 to 2005 were estimated, controlling for individual- and neighborhood-level variables. During the study period, 15% of the sample was readmitted for asthma (n=451). In the unadjusted cumulative hazard curves, children residing in the census tracts with the highest proportion of crowded housing conditions, racial minority residents, or neighborhood-level poverty had higher cumulative hospital readmission rates as compared with children who resided in less disadvantaged neighborhoods. In the fully adjusted models, children insured by Medicaid at the time of their index admission had readmission rates that were 33% higher than children who were privately insured. Our findings suggest that differences in health-care coverage are associated with higher readmission rates for pediatric asthma, but the relationship between neighborhood inequality and repeat hospitalizations for pediatric asthma requires further exploration. Social indicators such as minority race, Medicaid health insurance, and neighborhood markers of economic disadvantage are tightly interwoven in the U.S. and teasing these relationships apart is important in asthma disparities research.

Self-Management of Acute Asthma among Low-Income Urban Adults

One approach to address asthma disparities has been to create evidence-based guidelines to standardize asthma care and education. However, the adoption of these recommendations has been suboptimal among many providers. As a result, low-income minority patients may not be receiving adequate instruction in asthma self-management. In addition, these patients may fail to follow guideline-based recommendations. We conducted 25 interviews to identify the extent to which urban low-income adults have received training in, and implement, self-management protocols for acute asthma. Twenty-five adults (92% female; 76% African American; mean age 39) were enrolled. Only one subject had received asthma self-management training and only 10 (40%) used short-acting beta-2 agonist-based (SABA) self-management protocols for the early treatment of acute asthma. No subject used a peak flow meter or an asthma action plan. Most (52%) chose to initially treat acute asthma with complementary and alternative medicine (CAM) despite the availability of SABAs. Importantly, 21 (84%) preferred an integrated approach using both conventional and CAM treatments. Four themes associated with acute asthma self-management emerged from the qualitative analysis. The first theme safety reflected subjects' perception that CAM was safer than SABA. Severity addressed the calculation that subjects made in determining if SABA or CAM was indicated based on the degree of symptoms they were experiencing. The third theme speed and strength of the combination described subjects' belief in the superiority of integrating CAM and SABA for acute asthma self-management. The final themesense of identity spoke to the ability of CAM to provide a customized self-management strategy that subjects desired. It is unclear if subjects' greater use of CAM or delays in using SABA-based self-management protocols were functions of inadequate instruction or personal preference. Regardless, delays in, or under use of, conventional self-management protocols may increase the risk for an untoward outcome. To that end, all patents' acute asthma self-management strategies should be evaluated for their timeliness and appropriateness. This would be of particular importance for vulnerable populations who bear a disproportionate burden of the disease and who have the fewest resources.

Childhood Asthma, Public Housing, and Environmental Control: Differences Between Families Renting with Section 8 Vouchers and Those Living in the Projects

ABSTRACT Hazardous environments (both indoor and outdoor) play a role in explaining asthma disparities between poor and affluent children. Through a focus on Phoenix (Arizona) case, this article examines the historical development of subsidized housing and the contemporary role that it plays in protecting poor children with asthma from environmental triggers. Through in-depth interviews with parents, the ways in which living in subsidized housing influences control over the environment and by extension children's asthma are explored. Experiences of families living in public housing apartment complexes and those renting homes with Section 8 vouchers are compared. It is found that the choices offered to Section 8 families allow them more control over their environment, which allows them to create better microenvironments in which to manage asthma.

Asthma among WTC Children: Registry Yields First Child Health Report

The World Trade Center Health Registry (WTCHR), comprising persons most likely to have been heavily exposed to traumatic events and air pollution related to the World Trade Center attacks of 11 September 2001, includes 3,184 children under age 18 years who were living or attending school in lower Manhattan at the time, who were otherwise near the World Trade Center that morning, or who assisted in recovery efforts. In the first report of children enrolled in this registry, researchers observe that preschoolers exposed to smoke and dust from the collapsing towers had asthma rates twice the national average following the 9/11 attack, whereas asthma rates in exposed older children remained about average [EHP 116:1383–1390; Thomas et al.]. Children in certain ethnic groups also experienced disproportionate asthma rates, although the reasons for this are unclear. Data were collected in 2003 and 2004 by telephone interviews with parents of younger children or the children themselves if they had turned 18 since the attacks. More than half the children reported having respiratory symptoms after the attacks, including cough and sinus problems. Nearly 6% of all children reported having asthma diagnosed after 9/11. At the time of the interviews, 16% of children then aged 2–4 years had been diagnosed with asthma, more than twice the average of 7% for children that age in the Northeast. Asthma rates in older subjects, however, were just slightly higher than the Northeast rate. Childhood asthma normally develops in a child’s first five years of life, often after exposure to an environmental irritant. Smoke and dust from the collapsing towers might have acted as such an early trigger in susceptible preschoolers. The researchers speculate that older youngsters could have had fewer new diagnoses because most susceptible children had been diagnosed before 9/11. The researchers noted racial disparities in asthma rates. Black and Hispanic children in the WTCHR were twice as likely to be diagnosed with asthma as whites or Asians, both before and after the attacks. Reasons for the racial disparities are unclear, although prior studies on ethnic disparities in asthma suggest that both genetics and environment may play a role in etiology of the disease. Children of all ages and ethnicities were more likely to develop asthma if they were caught in the cloud of cement dust created by the collapsing towers, as pulverized cement dust is known to irritate mucous membranes. The WTCHR data have several limitations, including lack of information on how long after 9/11 symptoms appeared and the presence of co-factors for asthma. Despite these limitations, findings from the WTCHR, which constitutes the largest collection of post-disaster data of children, could have broad impact, given that tens of thousands of New York City children may have been exposed to smoke and dust on 9/11. Researchers also expect their data to improve understanding of risks to children exposed to other polluting disasters, such as the California wildfires.

Racial/Ethnic Variation in Parent Perceptions of Asthma

Black and Latino children with asthma have worse morbidity and receive less controller medication than their white peers. Scant information exists on racial/ethnic differences in parent perceptions of asthma. To compare parent perceptions among black, Latino, and white children with asthma in 4 domains: (1) expectations for functioning with asthma; (2) concerns about medications; (3) interactions with providers; and (4) competing family priorities. In this cross-sectional study, we conducted telephone interviews with parents of children with persistent asthma in a Medicaid health plan and a multispecialty provider group in Massachusetts. To measure expectations for functioning and other domains, we adapted multi-item scales from past studies. Associations between race/ethnicity and these domains were evaluated in multivariate analyses that controlled for age, gender, household income, parental education, insurance, and language. The response rate was 72%. Of the 739 study children, 24% were black, 21% Latino, and 43% white. Parents of black and Latino children had lower expectations for their children's functioning with asthma (P < .001), higher levels of worry about their children's asthma (P < .001), and more competing family priorities (P = .004) compared with parents of white children. Parents of Latino children had higher levels of concern about medications for asthma than parents of black or white children (P = .002). There were no differences among racial/ethnic groups in reports of interactions with the provider of their children's asthma care. Efforts to eliminate disparities in childhood asthma may need to address variation in expectations and competing priorities between minority and white families.

Race/ethnicity, language, and asthma care: findings from a 4-state survey

Latino and African American children have poorer asthma control than non-Latino white children, but few studies examine the association among race/ethnicity, language, and specific processes of asthma care. To evaluate the association of race/ethnicity and language with the quality of asthma care. A random sample of children from birth to the age of 17 years with asthma within 4 states (California, Texas, Illinois, and Alabama) was selected for the National Asthma Survey conducted by the National Center for Health Statistics from March 1, 2003, to March 10, 2004. Parents completed a telephone survey that included measures of asthma care quality. The final sample was 1,517 children. According to parental report, only 41.4% of children had an asthma management plan and 48.5% were ever advised by a clinician to control asthma by changing the child's home and school environment. African American and Latino children with persistent asthma had lower odds of taking controller medication than non-Latino white children. In multivariate analysis adjusting for annual income, insurance, and age, Latino children with Spanish parental interview, but not African American and Latino children with English parental interview, had poorer experiences with care than white children (ever taught what to do during an attack: odds ratio, 0.4 [95% confidence interval, 0.2-0.6]; and ever advised to change child's home and school environment: odds ratio, 0.5 [95% confidence interval, 0.3-0.8]). Differences in asthma care quality and controller use persist among racial/ethnic and language groups despite similar rates of planned encounters for asthma. Improving use of controller medications and counseling on environmental modifications are important for reducing asthma disparities.

Trends in Private Insurance, Medicaid/State Children's Health Insurance Program, and the Health-Care Safety Net

Disparities in asthma prevalence, severity, quality of care, and outcomes have been widely documented across racial/ethnic communities, among privately insured vs publicly insured patients, and according to patients' socioeconomic status, among other patient characteristics. In order to effectively address asthma disparities, changes will need to be made across all systems of care in which these subpopulations receive health-care services. The majority of current trends in private insurance, Medicaid/State Children's Health Insurance Program, and the safety net are likely to further exacerbate asthma disparities rather than help to reduce these disparities. Asthma cannot be effectively managed unless individuals have affordable access to a full range of services and receive coordinated, quality health care. Multiple policy levers will need to be simultaneously employed to ensure access to the full range of services needed for effective asthma management, especially among low-income and minority persons with asthma in order to reduce the gap in disparities. The needs of these patients must be thoughtfully addressed and strategically advocated for within all systems of care in which these subpopulations receive health services. This overall strategy must necessarily include consideration of the capacity of safety-net providers to meet the needs of uninsured and underinsured persons with asthma. This article reviews trends in health-care financing, in clinical management, and the health-care safety net, and assesses their likely impact on asthma disparities. It concludes with a discussion of key policy arenas that will have significant influence on the eventual success of efforts to reduce asthma disparities.

Advancing a Multilevel Framework for Epidemiologic Research on Asthma Disparities

Our understanding of asthma epidemiology is growing increasingly complex. Asthma outcomes are clearly socially patterned, with asthma ranking as a leading cause of health disparities among minority and low socioeconomic groups. Yet, the increasing prevalence and marked disparities in asthma remain largely unexplained by known risk factors. In the United States, asthma disproportionately affects nonwhite children living in urban areas and children living in poverty. Low socioeconomic status (SES), ethnic minority group status, and residence in an inner-city environment are closely intertwined in the United States, making it a challenge to fully disentangle the independent effects of each of these characteristics on asthma morbidity. In addition, studies show geographic variation in asthma outcomes across large cities and neighborhoods within cities that cannot be explained by economic factors alone. Although more limited data are available, studies in rural areas also suggest the stratification of risk based on SES and the proportion of minorities. Among low-SES areas, those with predominantly minority, segregated populations seem especially burdened. Marginalized populations of lower socioeconomic position are disproportionately exposed to irritants (eg, tobacco smoke), pollutants (eg, diesel-related particles), and indoor allergens (eg, cockroach and mouse allergen). Moreover, these marginalized individuals may also live in communities that are increasingly socially toxic, which, in turn, may be related to the increased experience of psychosocial stress that may influence asthma morbidity. Epidemiologic trends suggest that asthma may provide an excellent paradigm for understanding the role of community-level contextual factors in disease. Specifically, a multilevel approach that includes an ecological perspective may help to explain heterogeneities in asthma expression across socioeconomic and geographic boundaries that, to date, remain largely unexplained. Traditionally, asthma epidemiology has focused on individual-level risk factors and family factors. Far less attention has been given to the broader social context in which individuals live. A multilevel approach that explicitly recognizes the embedding of asthma within its biological, psycho-socioeconomic, environmental, and community contexts, is likely to provide a better understanding of asthma disparities at different stages in the life course. Is it simply asthma disparities or is it social disparities in asthma?

The Contributing Role of Health-Care Communication to Health Disparities for Minority Patients With Asthma

Asthma is a common, chronic illness with substantial morbidity, especially for racial and ethnic minorities in the United States. The care of the patient with asthma is complex and depends ideally on excellent communication between patients and health-care providers. Communication is essential for the patient to communicate the severity of his or her illness, as well as for the health-care provider to instruct patients on pharmacologic and nonpharmacologic care. This article describes evidence for poor provider/patient communication as a contributor to health-care disparities for minority patients with asthma. Communication problems stem from issues with patients, health-care providers, and health-care systems. It is likely that asthma disparities can be improved, in part, by improving patient/provider communication. While much is known presently about the problem of patient/provider communication in asthma, there is a need to improve and extend the evidence base on the role of effective communication of asthma care and the links to outcomes for minorities. Additional studies are needed that document the extent to which problems with doctor/patient communication lead to inadequate care and poor outcomes for minorities with asthma, as well as mechanisms by which these disparities occur.

The Potential for Reducing Asthma Disparities Through Improved Family and Social Function and Modified Health Behaviors

The National Workshop To Reduce Asthma Disparities assembled a multidisciplinary group comprised of scientists, clinicians, and community representatives to examine factors related to asthma disparities. Attention was given to the importance of discerning family, social, and behavioral factors that facilitate or impede the use of health-care services suitable to the medical status of an individual. This review highlights select biopsychosocial factors that contribute to these disparities, the manner in which they may contribute or protect persons affected by asthma, and recommended directions for future research.

Eliminating Asthma Disparities: A National Workshop To Set a Working Agenda

In February 2005, a national workshop was held in Chicago, IL, to address the problem of disparities in asthma. A multidisciplinary group of > 1,000 national experts reviewed key issues related to asthma health disparities; considered current research, clinical care, and policy related to this problem; and developed a set of recommendations to reduce these disparities. The themes addressed were genetics, indoor environment, outdoor environment, family/social function, behavioral health, health-care delivery, health-care communications, role of community, role of private insurance, role of safety net providers, and state and local policy.

Targeting Improvements in Asthma Morbidity in Chicago: A 10-Year Retrospective of Community Action

Chicago has been described as "asthma ground zero" due to its disproportionately high rates of asthma-related hospitalization and mortality. Asthma prevalence rates in Chicago are higher for whites and African Americans than the national average. In an effort to address the asthma burden and disparities in Chicago, multiple initiatives throughout the city have been launched and continue due largely to the support of the Otho S.A. Sprague Memorial Institute. The purpose of this article is to describe the policy, advocacy, educational, surveillance, research, quality improvement, community, and consortia activities over the past 10 years and their impact on asthma morbidity and disparities in Chicago.