Identifying asthma-related risks during hospitalization using the child asthma risk assessment tool

Objective: The Child Asthma Risk Assessment Tool (CARAT) identifies risk factors for asthma morbidity. We hypothesized that CARAT-identified risk factors (using a CARAT adapted for inpatient use) would be associated with future healthcare utilization and would identify areas for intervention.Methods: We reviewed CARAT data collected during pediatric asthma admissions from 2010-2015, assessing for risk factors in environmental, medical, and social domains and providing prompts for inpatient (specialist consultation or social services engagement) and post-discharge interventions (home care visit or home environmental assessment). Confirmatory factor analysis identified groups of CARAT-identified risk factors with similar effects on healthcare utilization (latent factors). Structural equation models then evaluated relationships between latent factors and future utilization.Results: There were 2731 unique patients admitted for asthma exacerbations; 1015 (37%) had complete CARAT assessments and were included in analyses. Those with incomplete CARAT assessments were more often younger and privately-insured. CARAT-identified risk factors across domains were common in children hospitalized for exacerbations. Risks in the environmental domain were most common. Inpatient asthma consults by pulmonologists or allergists and home care referrals were the most frequent interventions indicated (62%, 628/1015, and 50%, 510/1015, respectively). Two latent factors were positively associated with healthcare utilization in the year after index stay - social stressors and known/suspected allergies (both p < 0.05). Stratified analyses analyzing data just from those children with prior healthcare utilization also indicated known/suspected allergies to be positively associated with future utilization.Conclusions: Inpatient interventions to address social stressors and allergic profiles may be warranted to reduce subsequent asthma morbidity.

The influence of atopy and asthma on immune responses in inner-city adults

Asthma in the inner‐city population is usually atopic in nature, and is associated with significant morbidity and mortality. However, the underlying immune abnormalities that underlie asthma in urban adults have not been well defined. We investigated the influence of atopy and asthma on cytokine responses of inner‐city adult women to define immune abnormalities associated with asthma and atopy. Blood samples were collected from 509 of 606 inner‐city women enrolled in the Urban Environment and Childhood Asthma (URECA) study. We tested for associations between atopy and asthma status and cytokine responses in peripheral blood mononuclear cells incubated ex vivo with a panel of innate and adaptive immune stimulants. Atopic subjects had heightened Th2 cytokine responses (IL‐4, IL‐5, IL‐13) to cockroach and dust mite antigens, tetanus toxoid, and phytohemagglutinin (P < 0.05 for all). Differences in cytokine responses were greatest in response to stimulation with cockroach and dust mite. In a multivariate analysis, atopy was broadly related to increased Th2‐like responses to all antigens and PHA, while asthma was only weakly related to mitogen‐induced IL‐4 and IL‐5 responses. There were few asthma or allergy‐related differences in responses to innate stimuli, including IFN‐α and IFN‐γ responses. In this inner‐city adult female population, atopy is associated with enhanced Th2 responses to allergens and other stimuli, and there was little or no additional signal attributable to asthma. In particular, these data indicate that altered systemic interferon and innate immune responses are not associated with allergies and/or asthma in inner‐city women.

Factors Influencing Treatment of Asthma in Children in the Prehospital Setting

Study Objective:

The purpose of this study is to describe treatment of asthma in children by paramedics.

Design:

Retrospective review of an advanced life support (ALS) run reports over a one-year period.

Setting:

Review of paramedic response to pediatric respiratory emergencies in an urban, primarily inner-city, prioritized, dual-response emergency medical services (EMS) system.

Participants:

Patients < 19 years of age complaining of shortness of breath, paramedics, pediatric residents, and attending physicians.

Measurements and Main Results:

The medical records of 383 patients were reviewed for demographic and medical information. The population was separated into an ALS treatment group (received ALS) and a NO-ALS group (evaluation and/or oxygen only). Sixty percent of the patients (n = 231) were classified into the ALS group; 89% received epinephrine. Sixty-six percent (n = 101) of the NO-ALS patients received evaluation only, and the remaining 34% (n = 51) were evaluated and received oxygen. The ALS patients were older and had significantly higher respiratory rates and accessory muscle use than did the NO-ALS patients. Relief was reported in 66 % of ALS patients. No adverse reactions were reported in the ALS group. Determining factors influencing ALS treatment included age, the use of medications at home, wheezing, accessory muscle use, respiratory rate, and presence or absence of upper respiratory infection (URI) symptoms.

Conclusions:

This study demonstrates that asthma constitutes the majority of pediatric emergencies in the prehospital setting in this inner-city EMS system. The ALS treatment of pediatric asthma improves patient status. Factors which may influence paramedic judgment in treating asthma in children may be inappropriate. There is a critical need for further research in the prehospital treatment of pediatric asthma and in developing education interventions directed at the entire spectrum of prehospital care of pediatric emergencies.

Fifty years of pediatric asthma in developed countries: how reliable are the basic data sources?

Given the difficulties in diagnosing, or even defining, asthma in children, claims of a pediatric asthma epidemic in Canada and other developed countries are accepted with surprisingly little critical examination. We reviewed a broad range of data sources to understand how the epidemic evolved during the last 50 years and also to assess the reliability of the conclusions drawn from that data. We obtained Canadian National and Provincial data from Statistics Canada National Population Health Survey, and the British Columbia Ministry of Health respiratory database. International data were obtained by extensive review of pediatric asthma epidemiological surveys published during the last 50 years. In many developed countries, there have been three separate epidemics involving different aspects of pediatric asthma during the last 50 years: a double peaked mortality epidemic (1960s and 1980s), a hospital admission epidemic (peaked around 1990) and a steadily growing epidemic of children who report asthmatic symptoms on questionnaires. Canadian pediatric rates for asthma mortality (1-2/million/year) and hospital admission (1-2/thousand/year) are low and have fallen for the last 20 years. Rates based on questionnaire studies are high (10-15/hundred) and rose steadily over the same period. Objective reductions in asthma deaths and hospital admission likely reflect improved education and treatment programmes. Current claims of an epidemic based largely on subjective self-reported symptoms require more careful analysis. The possibility that symptom misperception, disease fashions, and poor recall, may be part of the explanation for the current high levels of self-reported symptoms deserves more attention.

Uncontrolled asthma and factors related to morbidity in an impoverished, rural environment

BACKGROUND

Asthma disproportionately affects children living in impoverished communities; however, factors related to asthma morbidity among impoverished rural children have not been adequately described.

OBJECTIVE

To examine factors associated with asthma morbidity among rural children living in the Arkansas Delta region.

METHODS

We performed a cross-sectional investigation of 109 rural children with asthma enrolled in public schools in the Arkansas Delta region. A questionnaire format and home inspection were used to examine participant, caregiver, and home characteristics.

RESULTS

The median age of the study participants was 9 years, 83% were African American, and 71% had an annual household income of $20,000 or less. Ninety-eight percent of participants were insured, and most fit the criteria for uncontrolled asthma, yet only 23% reported taking inhaled corticosteroids. Transportation problems were cited by 20%. In the past 4 weeks, more than 50% reported rescue medication use or exercise limitations of 2 or more days per week or nocturnal symptoms of more than 2 nights per month. Emergency department visits in the past 6 months were reported by 28%, and 43% reported an unscheduled physician's visits for asthma in the past 3 months. Sixty-four percent had 1 or more positive allergen skin test results, and allergic sensitization was associated with exposure to dust mite, dog, mouse, and cockroach allergens in the home.

CONCLUSION

Asthma morbidity was high among this cohort of atopic asthmatic children in the Arkansas Delta. Overuse of rescue medications and underuse of inhaled corticosteroids were prevalent even though the population was highly insured and had frequent health care use. Future asthma health initiatives should focus on the unique challenges associated with translating national guidelines-based care to rural pediatric populations.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00590304.

Human asthma phenotypes: from the clinic, to cytokines, and back again

A large body of experimental evidence supports the hypothesis that T-helper 2 (Th2) cytokines orchestrate allergic airway inflammation in animal models. However, human asthma is heterogeneous with respect to clinical features, cellular sources of inflammation, and response to common therapies. This disease heterogeneity has been investigated using sputum cytology as well as unbiased clustering approaches using cellular and clinical data. Important differences in cytokine-driven inflammation may underlie this heterogeneity, and studies in human subjects with asthma have begun to elucidate these molecular differences. This molecular heterogeneity may be assessed by existing biomarkers (induced sputum evaluation or exhaled nitric oxide testing) or may require novel biomarkers. Effective testing and application of emerging therapies that target Th2 cytokines will depend on accurate and easily obtained biomarkers of this molecular heterogeneity in asthma. Furthermore, whether other non-Th2 cytokine pathways underlie airway inflammation in specific subsets of patients with asthma is an unresolved question and an important goal of future research using both mouse models and human studies.

Increased prevalence of symptoms of rhinitis but not of asthma between 1990 and 2008 in Swedish adults: comparisons of the ECRHS and GA²LEN surveys

Background

The increase in asthma prevalence until 1990 has been well described. Thereafter, time trends are poorly known, due to the low number of high quality studies. The preferred method for studying time trends in prevalence is repeated surveys of similar populations. This study aimed to compare the prevalence of asthma symptoms and their major determinants, rhinitis and smoking, in Swedish young adults in 1990 and 2008.

Methods

In 1990 the European Community Respiratory Health Survey (ECRHS) studied respiratory symptoms, asthma, rhinitis and smoking in a population-based sample (86% participation) in Sweden. In 2008 the same symptom questions were included in the Global Allergy and Asthma European Network (GA²LEN) survey (60% participation). Smoking questions were however differently worded. The regions (Gothenburg, Uppsala, Umeå) and age interval (20–44 years) surveyed both in 1990 (n = 8,982) and 2008 (n = 9,156) were analysed.

Results

The prevalence of any wheeze last 12 months decreased from 20% to 16% (p<0.001), and the prevalence of “asthma-related symptoms” was unchanged at 7%. However, either having asthma attacks or using asthma medications increased from 6% to 8% (p<0.001), and their major risk factor, rhinitis, increased from 22% to 31%. Past and present smoking decreased.

Conclusion

From 1990 to 2008 the prevalence of obstructive airway symptoms common in asthma did not increase in Swedish young adults. This supports the few available international findings suggesting the previous upward trend in asthma has recently reached a plateau. The fact that wheeze did not increase despite the significant increment in rhinitis, may at least in part be due to the decrease in smoking.

The association between community crime and childhood asthma prevalence in Chicago

BACKGROUND

Little attention has been given to exposure to crime as a possible socioenvironmental contributor to variability in urban childhood asthma prevalence.

OBJECTIVE

To determine the association of violent crime, property crime, and drug abuse violations with childhood asthma prevalence in Chicago.

METHODS

In 2003-2005, the Chicago Initiative to Raise Asthma Health Equity conducted an asthma screening survey of children in grades K to 8 attending Chicago public and Catholic schools. Crime data were obtained from the Chicago Police Department. In addition to simple regression analysis, multilevel logistic regression analysis was performed to estimate the effect of criminal activity on neighborhood asthma variance.

RESULTS

Of the surveys returned, 45,371 (93%) were geocoded into 247 neighborhoods. Neighborhoods were divided into quartile groups by mean asthma prevalence (9%, 12%, 17%, and 22%). Criminal activity (annual incidence per 100,000 people) was significantly higher (P < .001) in neighborhoods with a high asthma prevalence, especially drug abuse violations, which increased more than 6-fold (461 vs 2,921), and violent crimes, which increased more than 3-fold (448 vs 1,566). After adjusting for community race/ethnicity, only violent crime continued to be significantly associated with the neighborhood asthma prevalence (odds ratio, 1.27; 95% confidence interval, 1.04-1.55, P < .05). When considered alongside sociodemographic and individual characteristics, violence continued to contribute significantly (P < .05), explaining 15% of neighborhood variation in childhood asthma.

CONCLUSIONS

Evidence suggests an association between violent crime and childhood asthma prevalence in Chicago. A deeper understanding of the mechanisms that underlie this association may lend insight into potential interventions to address urban asthma.

The 2007 National Asthma Education and Prevention Program asthma guidelines: accelerating their implementation and facilitating their impact on children with asthma

Nearly 2 decades have elapsed since the National Center for Health Statistics raised concerns regarding the trends in increasing asthma prevalence. Additional research highlighted the large racial disparities and geographic variations in asthma morbidity and mortality rates. Although there was little national consensus on the care of children with asthma at the time, there were improvements in the understanding of the mechanisms and treatment of asthma. It was in this context that the National Heart, Lung, and Blood Institute launched the National Asthma Education and Prevention Program, which convened its first panel of experts to create the national consensus clinical practice guidelines on the treatment of asthma. More than 15 years have passed since the publication of those first guidelines and, in August 2007, the National Heart, Lung, and Blood Institute released its newest updates, which are the product of the National Asthma Education and Prevention Program third expert panel. The release of the updated guidelines serves as an occasion to examine important issues regarding the dissemination and clinical implementation of National Asthma Education and Prevention Program guidelines. The goals of this report are to examine the adoption of earlier versions of the National Asthma Education and Prevention Program guidelines and to suggest opportunities for rapid adoption of the newly released guidelines.

How well were asthmatic patients educated about their asthma? A study at the emergency department

70 patients presented with acute asthma exacerbation requiring nebulised bronchodilator treatment at the emergency department of a teaching hospital in Kuala Lumpur, Malaysia, were interviewed over a two-week period in July 2001. The results showed that 45 (64%) patients had not been educated on the nature of asthma; 30 (43%) had not been advised on preventive measures or avoidance of triggers; 54 (77%) were not advised about the medications used and their side effects; 42 (60%) patients did not know the difference between reliever and preventive medications; 37 (53%) were unable to recognize features of worsening asthma and 68 (97%) were not told about the danger of non-prescribed self-medication or traditional medications. Only six (9%) patients were using peak flow meters and were taught self-management plans. The multiple regression results suggest that patients who were followed up at teaching hospital based clinics were better educated on asthma. In conclusion, asthmatic patients are still not educated well about their disease. Health care providers need to put more emphasis on asthma education so that the number of emergency room visits can be reduced.

Asthma in older adults

Asthma is underdiagnosed and undertreated in older adults. The classic symptoms, including episodic wheezing, shortness of breath, and chest tightness, are nonspecific in this age group. Older patients may underrate symptoms, and other diseases, such as chronic obstructive pulmonary disease, congestive heart failure, and angina, may have similar presentations. Objective measurements of lung function always should complement the history taking and physical examination. Management of asthma in older adults should include careful monitoring, controlling triggers, optimizing and monitoring pharmacotherapy, and providing appropriate asthma education. Adverse effects to commonly used asthma medications are more common in older adults, and careful monitoring of their use and adverse effects is important.

Addressing issues of asthma in inner-city children

For children living in the inner city, asthma tends to be more frequent and severe. Although the causes for this heightened severity of asthma are not clearly established, environmental allergens likely play a major role. To characterize, understand, and treat children with asthma living in the inner city better, the National Institutes of Allergy and Infectious Diseases of the National Institutes of Health established an Inner City Asthma Program in 1991. Over the past 15 years, 3 separate inner-city asthma research networks have been formed and funded by this institute. The work from these programs has led to important observations including evidence that environmental allergens, particularly cockroach, are important for sensitization and severity of asthma of the affected children. Furthermore, reductions in the allergen load can lead to improved asthma control. The most recent program, the Inner City Asthma Consortium, was formed in 2002 with a goal to develop immune-based therapy for children with asthma in the inner city and to determine mechanisms of these therapies as well as immunopathogenesis of asthma in these high-risk children. This article reviews these programs and how they have begun the effort to understand and treat children with asthma who live in inner cities better and what their findings mean in relationship to unique features of asthma in inner city children.

Epidemiology of asthma

The epidemiology of asthma is complex but essential in enhancing the understanding of a disease that affects millions of patients. Asthma is associated with significant morbidity and mortality. Asthma prevalence rates in the United States reached a plateau after 1998 with an estimated overall prevalence of 3.8% in 2003. Racial disparities exist and there are staggering differences in morbidity and mortality. The analysis of data collected from epidemiologic studies continues to be a critical part of enhancing the understanding of the pathophysiology of asthma, which will lead to improved patient outcomes.

Variation in total and specific IgE: effects of ethnicity and socioeconomic status

BACKGROUND

Asthma is common in minority and disadvantaged populations, whereas atopic disorders other than asthma appear to be less prevalent. It is unclear whether the same holds true for objective markers of sensitization.

OBJECTIVE

To determine the association of asthma, atopic disorders, and specific sensitization with race and socioeconomic factors.

METHODS

We analyzed total and specific IgE among 882 women (577 white, 169 black, and 136 Hispanic) who delivered a child at a large tertiary hospital in Boston, Mass, and who were screened for participation in a family and birth cohort study. Race/ethnicity and other characteristics were obtained from screening questionnaires. Addresses were geocoded, and 3 census-based geographic area socioeconomic variables were derived from block group information from the 1990 US Census.

RESULTS

Black and Hispanic women were more likely to come from areas with low socioeconomic indicators and were more likely to have asthma than white women. However, these women were less likely to have hay fever and eczema than their white counterparts. Compared with white women, black women had higher mean total IgE levels; had greater proportions of sensitization to indoor, outdoor, and fungal allergens; and were more than twice as likely to be sensitized to > or =3 aeroallergens.

CONCLUSION

The racial/ethnic disparities in atopic disorders may represent either underdiagnosis or underreporting and suggest that allergy testing may be underused in some populations. Differences in total IgE levels and specific allergen sensitization are likely a result of the complex interplay between exposures associated with socioeconomic disadvantage.

[Severe asthma in the general population: definition and prevalence]

RATIONALE

Severe asthma is a real public health problem because of its consequences on patients and its economic cost. Nevertheless, few epidemiological studies have focussed on severe asthma. The aim of this state of the art review is to describe the criteria used to estimate asthma severity and to assess the prevalence of severe asthma from population-based epidemiological studies.

OBSERVATIONS

Asthma severity has been defined in various ways in epidemiology, with criteria based on symptoms, hospitalisation, ventilatory function, discomfort caused by asthma attacks, and treatment. A high variability in the prevalence of severe asthma is observed, resulting mostly from the lack of standardisation in the phenotypes used, but also from a real geographical heterogeneity. Nevertheless, the prevalence of severe asthma may be reasonably estimated between 1 and 3% of the general population, both in children and adults.

CONCLUSION

Data from the literature show a lack of standardisation of the severe asthma phenotype. Further epidemiological studies are needed to understand the geographical variability in severe asthma prevalence.

Community organization to reduce the need for acute care for asthma among African American children in low-income neighborhoods: the Neighborhood Asthma Coalition

BACKGROUND

Low-income African Americans exhibit disproportionate prevalences, morbidity rates, and mortality rates for asthma.

OBJECTIVE

To determine whether a community-based intervention, the Neighborhood Asthma Coalition (NAC), conducted through a well-established neighborhood organization in St. Louis could improve awareness of asthma, change attitudes about its care, improve asthma management practices, and reduce the need for acute care for asthma.

METHODS

The NAC included educational programs for parents and children, promotional activities, and individualized support provided by trained neighborhood residents. African American children, 5 to 14 years of age, with at least 1 incident of acute care (emergency department visit or hospitalization) within the previous year were enrolled from 8 zip code areas with low-income residents and high proportions of Medicaid-eligible children, ie, 4 NAC neighborhoods and 4 comparable control neighborhoods. Evaluations included quarterly telephone interviews to assess asthma attitudes and management and sites of care. Audits of acute care sites covered 12 months before initiation of the NAC through 3 years of the program.

RESULTS

A total of 371 patients were contacted and determined to be eligible for the study, and 345 agreed to participate, representing a recruitment rate of 93%. Of those, 15 withdrew and 24 were lost to follow-up monitoring after the initial contact. In addition, 57 were excluded from analysis because of relocation or for other reasons. Utilization data to determine rates of acute care (emergency department visits and hospitalizations) were collected for 249 patients (100 NAC subjects and 149 control subjects). Acute care rates decreased for both the NAC and control groups from the year before intervention to the last year of intervention, with no significant differences between the NAC and control groups. Participation in NAC programming affected the acute care outcome; the NAC-low participation and control groups did not differ but the NAC-high participation group differed significantly from the pooled control and NAC-low participation groups in reductions in acute care rates. Both contacts with NAC staff members and attendance at educational events were associated with changes toward stronger views that asthma can be managed (partial correlation = .27 and partial correlation = .24, respectively). Structural equation modeling demonstrated that participation in the NAC was associated with positive changes on the Index of Asthma Attitudes scale and lower rates of acute care. Social isolation was associated with greater participation in the program and thus reduced care rates.

CONCLUSIONS

The NAC reached its intended audience, including those who were socially isolated, brought about changes in management practices, and was associated with promising reductions in acute care rates among active participants in the program.

Trends in otitis media among children in the United States

BACKGROUND

The prevalence of repeated otitis media (OM) increased during the 1980s, but it is unknown if the increase has continued.

OBJECTIVES

To determine trends in the prevalence of OM, early-onset OM, and repeated OM among US children from 1988 to 1994 and to identify factors that may explain any observed changes.

METHODS

The Third National Health and Nutrition Examination Survey was administered in 2 phases: phase I (1988-1991) and phase II (1991-1994), each comprising a national probability sample. OM (ever having had OM), early-onset OM (first episode at <12 months of age), and repeated OM (>or=3 episodes) were assessed for 8261 children <6 years of age.

RESULTS

After controlling for risk factors for OM, the prevalence of OM from phase I to phase II increased from 66.7% to 69.7% (odds ratio [OR] = 1.1; 95% confidence interval [CI] =.99, 1.1), early-onset OM increased from 41.1% to 45.8% (OR = 1.1; 95% CI = 1.03, 1.2), and repeated OM increased from 34.8% to 41.1% (OR = 1.2; 95% CI = 1.1, 1.4). This observed increase corresponds to 561,000 and 720,000 more children having early-onset OM and repeated OM, respectively. Child care use, early breastfeeding termination, asthma, and access to health care did not significantly increase from phase I to phase II. The prevalence of early-onset OM and repeated OM was higher for affluent children, but the greatest increase in prevalence was among impoverished children. There was an increase in allergic conditions from phase I to phase II for poor children (22.6% to 30.2%).

CONCLUSIONS

The prevalence of early-onset OM and repeated OM continued to increase among preschool children in the United States. Further research to investigate this increasing prevalence should explore changes in management practice and an increase in prevalence of allergic conditions among poor children.

Hospital readmissions for childhood asthma: a 10-year metropolitan study

Studies of asthma admissions in the St. Louis metropolitan area have disclosed substantial numbers of children with readmissions. To determine the magnitude of readmissions and attributes of children with readmissions, a retrospective analysis of 8,761 children with 14,905 asthma hospitalizations for January 1, 1990 through December 31, 1999 at the two university affiliated children's hospitals in St. Louis was undertaken. Patient attributes of age, sex, race/ethnicity, residence, payor status, length of stay, and month of admission were compared between patients admitted once during that period and patients admitted multiple times. Main outcome measures were the total number of admissions and time to readmission during the study interval. A Lin, Wei, Yang, and Ying model of time to readmission showed that African-American children with Medicaid or no insurance are at higher risk of readmission (risk ratio 1.28) than are African-American patients with commercial insurance or white/other race/ethnicity patients regardless of insurance. Probability of readmission increased from 30% after a first admission, 46% after a second, and 59% after a third. Prior admission was a more specific indicator of readmission with greater positive predictive value than ethnicity or insurance status or their combination.

Asthma in the elderly

Asthma is common in the elderly population and the differences between younger and older asthmatics should be appreciated (Table 2). Asthma is frequently overlooked in the geriatric population. Objective measures of pulmonary function can aid in a prompt diagnosis and lead to effective treatment and improved quality of life. Because smoking is an important risk factor for asthma-like symptoms of wheezing, cough, and sputum production, asthma is frequently confused with COPD. When airflow obstruction is found, attempts to demonstrate reversibility can uncover an asthmatic component to the disease. In patients who have asthma symptoms and no airflow obstruction, methacholine testing is helpful. When a normal methacholine challenge is present, a diagnosis of asthma can be excluded and the physician can pursue other diagnostic considerations such as heart failure, chronic aspiration syndrome, pulmonary embolic disease, and carcinoma of the lung. The onset of wheezing, shortness of breath, and cough in an elderly patient is likely to cause concern. Although the adage "all that wheezes is not asthma" is true at any age, it is especially true in the elderly. Diagnosis based on objective measures is essential.

Racial and income disparities in childhood asthma in the United States

OBJECTIVE

To examine racial and income disparities in asthma prevalence in US children, and disparities in morbidity and ambulatory health care use among children with asthma.

METHODS

Using 1993-1996 National Health Interview Survey data, we measured asthma prevalence and morbidity in children aged 3 to 17 years (N = 14 211) stratifying by race and poverty status. Measures of morbidity included asthma-related activity limitation and number of bed days. We used the ratio of asthma-related doctor contacts to number of bed days in the past 2 weeks to measure health care use adjusted for severity of illness.

RESULTS

An annual average of 7.4% of children aged 3 to 17 years had asthma. There were no significant differences in asthma prevalence between race and poverty groups. In contrast, asthma-related morbidity was higher among black and poor children. Black poor children were most likely to have activity limitations due to asthma: 49% were limited compared with about 20% of black nonpoor, white poor, and white nonpoor children. Among children with activity limitations, black children and white poor children were more likely to have severe limitations, and white nonpoor children were least likely. Finally, white nonpoor children had the highest level of ambulatory care use for asthma after accounting for disease severity, and black poor children had the lowest level.

CONCLUSIONS

We found no significant racial or income disparities in asthma prevalence among children in the United States. However, black children and poor children are at higher risk for activity limitation, more severe activity limitation, and relative underuse of ambulatory health care. Black children living in poverty are at highest risk. Targeted interventions to reduce the burden of asthma morbidity in this population are likely to reduce disparities in asthma morbidity as well as reduce overall childhood asthma morbidity.

Effect of cat and dog ownership on sensitization and development of asthma among preteenage children

An inverse relationship has been proposed between exposure to high quantities of cat allergen at home and both asthma and cat allergy. First- and second-grade children from Luleå, Kiruna, and Piteå, Sweden participated in an asthma questionnaire study (n = 3,431) and incidence was evaluated over the next 3 years. Skin testing was performed on the children in Luleå and Kiruna (n = 2,149). The strongest risk factor for incident cases of asthma was Type 1 allergy (relative risk [RR], 4.9 [2.9-8.4]), followed by a family history of asthma (RR, 2.83 [1.8-4.5]). Living with a cat was inversely related both to having a positive skin test to cat (RR, 0.62 [0.47-0.83]) and incidence of physician-diagnosed asthma (RR, 0.49 [0.28-0.83]). This effect on incident asthma was most pronounced among the children with a family history of asthma (RR, 0.25 [0.08-0.80]). The evidence also suggests that many of the children exposed to cats at home can develop an immune response that does not include immunoglobulin E. Weaker protective trends were seen with dog ownership. The traditional thinking that not owning cats can provide protection against developing allergy and asthma among those with a family history of allergy needs to be re-evaluated. In a community where cat sensitization was strongly associated with asthma, owning a cat was protective against both prevalent and incident asthma.

Trends in childhood asthma: prevalence, health care utilization, and mortality

OBJECTIVES

Our objective was to use national data to produce a comprehensive description of trends in childhood asthma prevalence, health care utilization, and mortality to assess changes in the disease burden among US children.

METHODS

Five data sources from the National Center for Health Statistics were used to describe trends in asthma for children aged 0 to 17 years from 1980 to the most recent year for which data were available. These included the National Health Interview Survey (NHIS), the National Ambulatory Medical Care Survey, the National Hospital Ambulatory Medical Care Survey, the National Hospital Discharge Survey, and the Mortality Component of the National Vital Statistics System.

RESULTS

Asthma prevalence increased by an average of 4.3% per year from 1980 to 1996, from 3.6% to 6.2%. The peak prevalence was 7.5% in 1995. In 1997, asthma attack prevalence was 5.4%, but changes in the NHIS design in 1997 preclude comparison to previous estimates. Asthma attack prevalence remained level from 1997 to 2000. After a decrease between 1980 and 1989, the asthma office visit rate increased by an average of 3.8% per year from 1989 to 1999. The asthma hospitalization rate grew by 1.4% per year from 1980 to 1999. Although childhood asthma deaths are rare, the asthma death rate increased by 3.4% per year from 1980 to 1998. Children aged 0 to 4 years had the largest increase in prevalence and had greater health care use, but adolescents had the highest mortality. The asthma burden was borne disproportionately by black children throughout the period. Racial disparities were largest for asthma hospitalizations and mortality: compared with white children, in 1998-1999, black children were >3 times as likely to be hospitalized and in 1997-1998 >4 times as likely to die from asthma.

CONCLUSIONS

Recent data suggest that the burden from childhood asthma may have recently plateaued after several years of increasing, although additional years of data collection are necessary to confirm a change in trend. Racial and ethnic disparities remain large for asthma health care utilization and mortality.

Relationship of adherence to pediatric asthma morbidity among inner-city children

OBJECTIVES

Morbidity from asthma among children is one of the most important US health concerns. This study examines the relationship of baseline nonadherence to subsequent asthma morbidity among inner-city children.

METHODS

A multisite, prospective, longitudinal panel study was conducted of 1199 children who were aged 4 to 9 years and had asthma and their caregivers, most of whom were parents, in emergency departments and clinics at 8 research centers in 7 US metropolitan inner-city areas. Nine morbidity indicators were collected at 3, 6, and 9 months after baseline, including hospitalizations, unscheduled visits, days of wheeze/cough, and days of reduced activities.

RESULTS

Children whose caregivers scored high on a new measure, Admitted Nonadherence, experienced significantly worse morbidity on 8 of the 9 measures. Children who scored high on a new Risk for Nonadherence measure experienced significantly worse morbidity on all 9 morbidity measures. Multiple and logistic regressions found that the adherence measures had independent significant effects on morbidity. Combining the measures improved estimates of morbidity: children whose caregivers were poor on either adherence measure had worse morbidity than those with good adherence on both, eg, rate of hospitalization was twice as high, they missed more than twice as much school, had poorer overall functioning, and experienced more days of wheezing and more restricted days of activity.

CONCLUSIONS

Risk for Nonadherence and Admitted Nonadherence independently and jointly predicted subsequent asthma morbidity. Targeting risks for nonadherence may be an effective intervention strategy. Most risks can be controlled by physicians through reducing the complexity of asthma regimens, communicating effectively with caregivers about medication use, and correcting family misconceptions about asthma medication side effects.

Reducing disparities in asthma care: priorities for research--National Heart, Lung, and Blood Institute workshop report

Minority groups with diverse racial and ethnic heritages and persons living in poverty are much more likely to die of asthma and to require emergency care for exacerbations of asthma than white persons not living in poverty. The National Heart, Lung, and Blood Institute convened a multidisciplinary group of expert scientists and clinicians to review current research aimed at understanding risk factors for these disparities in asthma health outcomes, to describe key barriers to improving asthma outcomes, and to establish priorities for future research. Education programs for asthma and other chronic diseases were reviewed. Successful elements of clinic and community-based programs were identified. Factors potentially involved in producing disparities include gene-environment interaction, psychologic and social factors, and socioeconomic status. Stress potentially contributes to asthma morbidity at both the individual and community level. Recommendations are made to stimulate research to understand risk factors for disparities and their mechanisms (e.g., gene-by-environment interactions and the role of stress), to define appropriate research designs and methods for evaluating behavioral and community interventions, and to examine how differential access to care contributes to morbidity. Research is encouraged to identify strategies that improve cultural adaptation and adoption of proven programs in a variety of populations.

A computerized reminder strategy is effective for annual influenza immunization of children with asthma or reactive airway disease

BACKGROUND

Influenza virus infection frequently triggers asthma exacerbation and hospitalization. Annual influenza immunization is recommended for children with chronic conditions, including those with asthma or reactive airway disease (RAD); however, <10% receive it each year.

METHODS

In September, 1997, we instituted a computerized staged reminder strategy for annual influenza immunization of children with asthma/RAD at the Scott and White Pediatric Clinic in Temple. A reminder letter, followed six weeks later by an autodial recall telephone message, was sent to the parent/guardian of children with asthma/RAD using the Shared Medical Systems to identify children with asthma/RAD and the Integrated Client Encounter System to record immunizations. The effect of this computerized reminder system on the influenza immunization rate of a cohort of 925 Scott and White Pediatric Clinic children with asthma/RAD was examined for the 1996 to 1997 and 1997 to 1998 influenza seasons, before and after intervention.

RESULTS

A significant increase in influenza immunization rate from 5.4% to 32.1% occurred in all age groups, regardless of the insurance status. The medically attended acute respiratory illness rate per 100 subjects was significantly higher in vaccinated than in unvaccinated children for each of the two influenza epidemics and in the period between the two epidemics.

CONCLUSION

A computerized reminder letter followed by an autodial recall telephone message is effective in increasing the influenza immunization rate of children with asthma/RAD. Children with significantly higher respiratory morbidity during and in between two influenza epidemics were more likely to be immunized after receiving written and telephone autodial reminders.

Asthma hospitalization trends in Charleston, South Carolina, 1956 to 1997: twenty-fold increase among black children during a 30-year period

OBJECTIVE

The increase in asthma prevalence has been documented worldwide, affecting many races living in many different climates. Multiple studies have demonstrated that the most striking prevalence and morbidity of asthma in the United States has been in black children, but little research has determined the scale of the increase, or specifically when the disease became severe in this group. This study sought to determine exactly when the rise in asthma hospitalizations among black patients began and what the pattern of asthma hospitalizations has been in different races and age groups over a 40-year period in 1 urban area.

METHODS

A retrospective chart review of discharges from the Medical University of South Carolina was conducted from 1956 to 1997. Charts with the primary discharge diagnosis of asthma were examined for discharge date, race, and age group (0- to 4-year-olds, 5- to 18-year-olds, 19- to 50-year-olds, > or =51-year-olds). The diagnostic codes used were based on the International Classification of Diseases (ICD)-6, 1956-1957; ICD-7, 1958-1967; ICD-8, 1968-1978; and ICD-9, 1979-1997. Over the period studied, this hospital was the primary inpatient provider for children in this area, and the only provider for uninsured children. Between 1960 and 1990, the racial makeup of the area remained stable, as did the percentage of blacks living at the poverty level. The raw number of asthma discharges, rate per 10 000 discharges of the same race, and rate per 100 000 population in Charleston County were tabulated for each age group and racial category.

RESULTS

Over the time period examined, there has been a progressive increase in asthma hospitalizations in black individuals of all age groups and in whites under 18 years. The most striking increase has been in black children 0 to 18 years old (figure). The increase either as raw values or as a rate per 100 000 began around 1970, and was linear. This increase in black children discharged with asthma as a rate per 100 000 population was 20-fold: the rate increased from 18 in 1970 to 370 in 1997. Asthma discharges as a rate per 10 000 black children discharged increased by 24-fold from 1960 to 1997. Total discharges from the hospital increased from 49 000 to 128 000 per year over this period. Blacks made up only 28% of discharges in 1957, but that proportion increased to 56% in 1960 and remained relatively stable over the following 35 years. The increase seen in white children 0 to 18 years of age as a rate per 100 000 population was 5-fold and began around 1980. Both increases seem to be consistent over the time period studied, and continued to 1997. [figure: see text].

CONCLUSIONS

Among a predominantly poor black population living in a southern US city, there has been a steady increase in childhood asthma hospitalizations over the past 30 years. A significant although less dramatic rise has occurred in white children. Over this time period, although there have been many changes in lifestyle that could have contributed to this rise, there have been no major changes in housing conditions for poor patients. In addition, Medicaid coverage for children in South Carolina did not change significantly until 1999. The time course of these increases parallels increases reported in other Western populations, suggesting that there must be 1 or more common factors contributing to the rise. Many explanations have been offered for the changes in incidence and severity of asthma. The scale of the change, time course, and linearity of the increase in this study represent a challenge to many of the hypotheses proposed to explain this epidemic.

Ambient urban Baltimore particulate-induced airway hyperresponsiveness and inflammation in mice

Airborne particulate matter (PM) is hypothesized to play a role in increases in asthma prevalence, although a causal relationship has yet to be established. To investigate the effects of real-world PM exposure on airway reactivity (AHR) and bronchoalveolar lavage (BAL) cellularity, we exposed naive mice to a single dose (0.5 mg/ mouse) of ambient PM, coal fly ash, or diesel PM. We found that ambient PM exposure induced increases in AHR and BAL cellularity, whereas diesel PM induced significant increases in BAL cellularity, but not AHR. On the other hand, coal fly ash exposure did not elicit significant changes in either of these parameters. We further examined ambient PM-induced temporal changes in AHR, BAL cells, and lung cytokine levels over a 2-wk period. Ambient PM-induced AHR was sustained over 7 d. The increase in AHR was preceded by dramatic increases in BAL eosinophils, whereas a decline in AHR was associated with increases in macrophages. A Th2 cytokine pattern (IL-5, IL-13, eotaxin) was observed early on with a shift toward a Th1 pattern (IFN-gamma). In additional studies, we found that the active component(s) of ambient PM are not water-soluble and that ambient PM-induced AHR and inflammation are dose- dependent. We conclude that ambient PM can induce asthma-like parameters in naive mice, suggesting that PM exposure may be an important factor in increases in asthma prevalence.

School attendance and school performance: a population-based study of children with asthma

OBJECTIVE

To analyze school attendance and school achievement as outcomes of the care of children with asthma.

METHODS

A previously identified Rochester, Minnesota, cohort of children with asthma and age- and sex-matched children without asthma were studied. School attendance, standardized achievement test scores, grade point average, grade promotion, and class rank of graduating students for children with asthma and control subjects were obtained from the Rochester Public School system.

RESULTS

Children with asthma (n = 92) and age- and sex-matched non-asthmatic control subjects with 640 school-years of observation were studied. Children with asthma had 2.21 (95% CI, 1.41 to 3.01) more days absent than children without asthma. There was no significant difference in standardized achievement test scores (reading percentile difference 1.22% [95% CI, -3.68 to 6.12], mathematics percentile difference 2.36% [95% CI, -2.89 to 7.60], language percentile difference 2.96% [95% CI, -4.03 to 7.15]). There was no significant difference in grade point average, grade promotion, or class rank of graduating students.

CONCLUSION

In this community, although children with asthma had 2 excess days of absenteeism, the school performance of children with asthma was similar to that of children without asthma.

Children's environmental health risks: a state-of-the-art conference

More than 100 academic and private-sector researchers, government officials, politicians, and public health practitioners met to discuss issues regarding children's environmental health. Of special concern were the lack of toxicological data on many chemicals, the paucity of studies of children's exposure to these chemicals, and our limited understanding of pediatric toxicology. The increased incidence of childhood cancers and asthma were also of concern, as was our lack of understanding of how exposures to multiple environmental chemicals in low doses may influence child growth and development, disrupt endocrine function, and stimulate development of chronic diseases. An agenda for basic research, education and outreach, and policy and program development was created, with a goal of moving children's environmental health issues forward in a logical and thoughtful manner.

Symptom perception during acute bronchoconstriction

The hypothesis underlying the present study was that some of the variability in symptom intensity seen during acute bronchoconstriction may result from varying intensities of several stimuli yielding several sensations that can be identified by specific descriptive expressions (symptoms). A total of 232 subjects inhaled methacholine in doubling concentrations to a 20% decrease in FEV(1), or 64 mg/ml. The study identified the prevalence of dyspnea, nonspecific discomfort associated with the act of breathing, and 10 specific symptom expressions. Each symptom intensity was rated in Borg scale units. The contribution of the specific symptoms to the intensity of dyspnea is illustrated in the following equation (r = 0. 84): Dyspnea = 0.44 + 0.19 Difficult breathing + 0.41 Chest tightness + 0.20 Breathlessness + 0.14 Labored breathing + 0.11 Chest pain. Dyspnea was more intense with broncho-constriction, baseline pulmonary impairment, weight, and sex (being female). Dyspnea was less intense with age (being older) and as airway responsiveness to methacholine increased (p < 0.05 for all factors). Chest tightness and chest pain were at polar extremes on the discrimination scale, i.e., easily discriminated; chest tightness, difficult and labored breathing were not easily discriminated.

Demographic characteristics of patients experiencing near-fatal and fatal asthma: results of a regional survey of 400 asthma specialists [see comment]

BACKGROUND

Case-control studies now describe a growing number of younger patients with varying levels of asthma severity who experience near-fatal or fatal asthma unexpectedly at home, en route to the hospital, or in public places.

OBJECTIVE

To collect case reports and analyze the demographic characteristics and patient profiles that may help identify predisposing factors which trigger near-fatal and fatal asthma episodes.

METHODS

In order to gather case reports and analyze the demographics and clinical characteristics of patients experiencing near-fatal and fatal asthma, a questionnaire on near-fatal and fatal asthma was distributed to 400 regional asthma specialists.

RESULTS

Forty physicians reported 25 cases of near-fatal asthma and 20 cases of fatal asthma. Twenty-five patients (13 males and 12 females) with a mean age of 29.4 years experienced near-fatal asthma. The time of onset of the near-fatal event was sudden (less than 3 hours) in 60% of cases and 76% of the episodes occurred at home or en route to the hospital. All 25 patients were using short acting inhaled beta agonists and 88% were reportedly using inhaled corticosteroids on a daily basis. Good to excellent compliance was noted in 60% of patients. Six patients were using a peak flow meter prior to their near-fatal attack. Predisposing psychosocial factors for life threatening asthma were noted in 44% of patients. Twenty patients, (4 males and 16 females) with a mean age of 21.7 years experienced fatal asthma. The time of onset of the fatal event was sudden (less than 3 hours) in 80% of cases and all but one patient died at home, en route to the hospital, or in a public place. All 20 patients were using short acting inhaled beta agonists, 80% were reportedly on daily inhaled corticosteroids and six patients were on oral corticosteroids. Good to excellent compliance was noted in 60% of patients. Only two patients were using a peak flow meter immediately prior to their fatal attack. Predisposing psychosocial factors for life threatening asthma were noted in 45% of decedent patients. Risk factors for fatal asthma included running in cold weather, over relying on home nebulizers, and a delay in seeking care on long holiday weekends.

CONCLUSIONS

While approximately 50% of the patients in this survey had moderate to severe asthma tainted by adverse psychosocial factors, nearly half of near-fatal and fatal attacks occurred suddenly and unexpectedly, outside the hospital in stable, younger, atopic, reportedly compliant patients utilizing inhaled corticosteroids on a daily basis. This regional survey supports the need for additional studies and the establishment of a national case registry to collect case reports and analyze the demographics and clinical characteristics of patients experiencing near-fatal and fatal asthma in order to further define the risk factors and develop preventative protocols for patients at risk for near-fatal or fatal asthma.

Effects of CpG DNA on Th1/Th2 balance in asthma

Thus, in our studies, we demonstrated that CpG ODN are effective in preventing the development of eosinophilic airway inflammation and bronchial hyper-reactivity in a murine model of asthma. Antigen-associated elevation of serum IgE levels is also suppressed. CpG ODN, administered in conjunction with antigen, is also effective in down-regulation of established Th2 responses. This protection is neither murine strain-dependent nor model-dependent. Although these effects of CpG ODN are associated with the induction of the Th1 cytokines IFN-gamma and IL-12, neither cytokine is absolutely required for the protection. These results suggest that CpG ODN may be an effective immunomodulatory agent in the treatment, and possibly prevention, of asthma.

Emergency department visits by urban African American children with asthma

BACKGROUND

Asthma morbidity among African American children has been identified as a significant national health concern. High emergency department use is one index of this morbidity and may reflect disease severity, disease management, and social factors.

OBJECTIVE

This study examined the prevalence and correlates of emergency department use and other indices of asthma morbidity among a sample of urban, low-income, African American children.

METHODS

Parents of 392 elementary school children with asthma who had consented to participate in an asthma education program were interviewed by phone according to a standardized protocol.

RESULTS

Children had a mean of 6.2 days of restricted activity (SD 8.1) and 7.9 symptomatic nights (SD 8.1). The mean number of school days missed because of asthma was 9.7 (SD 13.5). Among children with asthma symptoms in the past 12 months, 73.2% could identify a specific physician or nurse who provided asthma care. For those families without an identified asthma primary care provider, 39.3% received their usual asthma care from the emergency department. A total of 43.6% of the children had been to the emergency department for asthma care without hospitalization in the previous 6 months. Close to 80% of children reported using one or more prescribed asthma medication, and of these only 12% reported using inhaled anti-inflammatory medications. Families of children who had used the emergency department in the prior 6 months reported more asthma symptoms, lower social support, problems paying for health care, and the absence of a hypoallergenic mattress cover and that they had seen a physician for regular asthma care in the past 6 months.

CONCLUSIONS

We conclude that asthma management for children in the inner city relies on episodic care and emergency care, that asthma medication management does not conform to current guidelines, and that asthma symptoms resulting in school absences and workdays lost are prevalent.

Changes in asthma claims in a Medicaid population from 1991-1994

Previous reports have found an increase in asthma prevalence and severity during the 1980s. The purpose of this study was to evaluate changes in asthma claims in a cohort of Medicaid enrollees from 1991 through 1994. A historical study used Ohio Medicaid claims data for fiscal years 1989 through 1994. Adult and pediatric enrollees with at least one claim for asthma care during fiscal year 1989 who subsequently were continuously eligible through fiscal year 1994 were divided into 2 cohorts consisting of those with (Cohort 1) or without (Cohort 2) an asthma claim in 1990. Claims were then analyzed forward from 1991-1994. Patients consisted of 3,027 enrollees, including 2,206 children and 821 adults. Overall emergency department visits increased in both cohorts, primarily due to an increase in adult visits. Visits by children who were preschool-aged in 1989 decreased. Patients in the cohort with an asthma visit in both 1989 and 1990 continued to have an increased frequency of emergency department (ED) visits compared to cohort 2. Outpatient visits decreased in both cohorts but the decrease was greater in cohort 1 in spite of the assumption that these patients should have greater attendance at outpatient clinics. The percentage of patients with an outpatient clinic visit within 3 days of their ED visit also decreased. Admissions decreased in both cohorts indicating that there was not a marked increase in asthma severity. Patients in cohort 1 with ED visits in 2 successive years represent those under relatively poorer control. In spite of a continued higher frequency of ED use, these patients had decreased use of outpatient facilities. Severity to the extent reflected by admissions did not increase over this period. Further research may demonstrate that improved outpatient management and followup of higher frequency ED users may lead to greater asthma control.

Comparison of emergency room asthma care to National Guidelines

BACKGROUND

National Asthma Education and Prevention Program (NAEPP) guidelines were first released in 1991. To date there have been no studies published comparing them with actual care given.

OBJECTIVE

The aim of this study was to compare the documented care given in the emergency room (ER) of an urban tertiary care hospital with 1991 NAEPP guidelines.

METHODS

A total of 1858 urban emergency room records with a diagnosis of asthma or reactive airway disease were recovered in 1 year (9/95 to 8/96) from pediatric and adult patients seen in the ER. Ten percent (n = 181) of the charts were reviewed for documentation of history, assessment of severity of attack, treatment given, and disposition.

RESULTS

History of present attack was documented consistently in all age groups. Nocturnal symptoms were noted in 11%, and frequency of beta agonist use in 38% of the charts. Previous ER visits, hospitalization, ICU admissions, and intubations (HCUM) were documented in 70%. Accessory muscle use was recorded in 76% of the infants and 21% of the adults. Peak flows were obtained in 31% of children and 64% of adults. Steroids were given in the ER in 59% of infants, 83% of children, and 49% of adults. Pediatric patients were referred to their primary care provider 90%, and to pulmonary or allergy clinic 4% of the time. Adults were referred to allergists or pulmonologists 32% of the time.

CONCLUSION

There are significant differences in ER evaluation and treatment when compared with the 1991 NAEPP guidelines. Differences also exist between various age groups within the same institution.

An investigation of the medical care utilization of children with severe asthma according to their type of insurance

A comparison of the medical care utilization of children with severe asthma according to insurance type was performed. Subjects were grouped by which type of insurance they had: capitated, fee for service, or Medicaid insurance. Medical records were coded into utilization categories, by presenting complaint, sick- or well-child visit, and if a generalist or specialist provided care during the visit. The Medicaid group had less specialist, sick-child care than the groups with capitated or fee for service insurance. The Medicaid group also had more emergency room visits than the other two groups. The three groups had a similar amount of total physician/clinic visits. Even though similar care was shown to be available for those with Medicaid insurance, this low resource group often uses expensive emergency room care.

The natural history of asthma in adults: the problem of irreversibility

Asthma is common, affecting 5% to 10% of adults; asthma is progressive, leading to irreversible obstruction in 80% of elderly patients; and asthma is complex, often complicated by coexisting lung diseases. This loss of lung function results from 4 independent pathologic conditions: (1) airway remodeling, especially in the small airways, from the lymphocytic-eosinophilic inflammation that characterizes asthma; (2) bronchiectasis; (3) postinfectious pulmonary fibrosis; and (4) emphysema and chronic bronchitis from tobacco smoke. Deterioration in lung function develops faster in nonallergic patients with intrinsic asthma during the period shortly after onset of asthma and in older patients. About 4% of patients die of asthma, and most are elderly. Death most often results from complications of irreversible obstruction or cardiotoxicity of bronchodilator therapy. More research is needed to improve therapy for preventing remodeling of small airways, to confirm the frequency of bronchiectasis and postinfectious fibrosis and to determine their causes, and to develop diagnostic criteria to identify these complications. Meanwhile, clinicians treating adult asthmatic patients need to be aggressive in preventing the damage from cigarette smoke; in immunizing for influenza and pneumococcus infection and identifying and treating respiratory infections, particularly at times of acute exacerbations; in diagnosing and managing bronchiectasis; and in objectively confirming the efficacy of asthma therapy to prevent illness from overtreatment with glucocorticoids and bronchodilators.

The challenge of inner-city asthma

Racial and ethnic minorities of low socioeconomic status residing in urban environments currently referred to as inner cities appear to represent a population that is disproportionately at high risk for asthma morbidity and mortality. Epidemiologic studies suggest that key risk factors contributing to asthma morbidity within the inner city include social demography, the physical environment (indoor and outdoor), and health care access and quality. This epidemiologic literature has helped to define opportunities for successful intervention strategies in these high-risk populations. Studies of the effectiveness of community-based and health system-based interventions with specific focus on inner-city populations are beginning to emerge in the literature.

Emergency room visits of asthmatic children, relation to air pollution, weather, and airborne allergens

BACKGROUND

The worldwide increase in the incidence, prevalence, and severity of asthma may suggest that environmental factors play a role in these epidemiologic changes.

OBJECTIVE

To examine the correlations between air pollutants, weather conditions, airborne allergens, and the incidence of emergency room (ER) visits of children with acute asthma attacks.

DESIGN

One-year prospective study. Data of daily concentration of air pollutants, weather conditions, and selective airborne allergens were collected and compared with the number of ER visits of asthmatic children.

SUBJECTS

1076 asthmatic children (aged 1 to 18 years) who presented at the Pediatric ER between January 1 and December 31, 1993.

RESULTS

Correlations between fluctuations in ER visits of asthmatic children and various environmental parameters were more relevant for weekly than for daily values. Emergency room visits correlated positively with concentrations of NOx, SO2 and with high barometric pressure; and negatively with O3 concentration and minimal and maximal temperature. There were no significant correlations with concentrations of particulates, humidity, or airborne pollen and spores. An exceptionally high incidence of ER visits of asthmatic children was observed during September. This peak coincided with the beginning of the school year and the Jewish holidays. The correlations between ER visits and the environmental factors increased significantly when the September peak was excluded, revealing that 61% of the variance in ER visits was explained by NOx, SO2, and 03 concentrations, 46% by weather parameters, 66% by NOx, SO2 and barometric pressure, and 69% by the combination of air pollutants and weather parameters.

CONCLUSION

The major factors found to be associated with ER visits of asthmatic children were high NOx, high SO2, and high barometric pressure. Negative correlation was found between ER visits of asthmatic children and ozone concentrations. The particularly high number of ER visits at the beginning of the school year and the Jewish holidays was probably associated with an increase in the number of viral infections and/or emotional stress.

Asthma and reproductive medicine

Asthma is a common disease affecting approximately 5 percent of the population and is a major cause of disability. Research interest in the condition is high because of frequent reports that the incidence, prevalence, severity, and mortality rates have been rising in recent years. Although the etiology remains elusive, knowledge about its pathophysiology is extensive and detailed, which in turn has spawned an impressive array of effective and safe drugs to prevent and treat acute exacerbations. Pharmacotherapy is enhanced by appropriate environmental control measures and immunotherapy for the significant number of asthmatics with an allergic component to their disease. The pregnant asthmatic may pose special requirements for the small minority with severe corticosteroid-dependent disease or those subject to frequent attacks. However, the great majority of asthmatic women need not face much risk of adverse effects on the course of the pregnancy or significant fetal or perinatal abnormalities, as long as appropriate preventive measures and monitoring are taken.

Relationships of race and socioeconomic status with prevalence, severity, and symptoms of asthma in Chicago school children

BACKGROUND

Asthma mortality rates in Chicago are among the highest in the United States, with substantially greater rates in poor and minority populations. How much of the differential can be attributed to differences in prevalence versus severity or access to care has not been determined.

OBJECTIVE

To examine rates of asthma prevalence, severity, and symptoms and to explore the relationships of these rates to race and socioeconomic status in a random sample of Chicago school children.

METHODS

Self-administered survey.

RESULTS

Overall, rates of asthma were higher than previously reported, with 16% of students in the stratified cluster random sample of 3,670 children in the 7th and 8th grades having had asthma. Prevalence rates were significantly higher in schools with >98% African Americans than in other schools, with the highest prevalence rates seen in African American schools in low income neighborhoods. Rates were associated with the percent of African American children in the school and with median income of the school's census tract. Relationships were most consistent with indices of more severe disease.

CONCLUSIONS

Asthma prevalence is higher than previously noted, with rates greatest in minority and low income populations. Differences are more striking for measures of severity than for symptoms of wheezing, but are far less than previously reported differences in mortality, suggesting that additional factors, such as differential access to continuous health care, may be affecting high death rates from asthma in Chicago.

Health service use by African Americans and Caucasians with asthma in a managed care setting

Managed care plan members provide a population for analysis that minimizes the financial barriers to routine medical care that have been linked to high rates of asthma-related hospitalization, emergency care, and mortality among urban African Americans. We examined patterns of asthma care among 464 African American (AA) and 1,609 Caucasian (C) asthma patients, age 15 to 45 yr, in a southeast Michigan managed care system during 1993. Compared with C, AA had fewer visits to asthma specialists (0.32 versus 0.50 visits/yr, p = 0.002), and filled fewer prescriptions for inhaled steroids (1.44 versus 1.74 Rx/yr, p = 0.038), while being more likely to visit the emergency department with asthma (0.71 versus 0.28 visits/yr, p < 0. 001), to be hospitalized with asthma (0.08 versus 0.03 admissions/yr, p = 0.002), or to have filled prescriptions for oral steroids (0.91 versus 0.59 Rx/yr, p < 0.001). AA were equally likely to have visited a primary care physician for asthma (0.95 versus 0.93 visits/yr, p = 0.81). Similar physician visit profiles and discrepancies in the use of oral steroids persisted when analyzing exclusively low socioeconomic status subgroups. These results suggest that ethnic differences in patterns of asthma-related health care persist within managed care settings and are only partially due to financial barriers.

Inhaled corticosteroids and the prevention of readmission to hospital for asthma

Despite the proven efficacy of inhaled corticosteroids in reducing airway inflammation and their increasing use for the treatment of asthma since the mid 1980s, hospitalization for asthma has been increasing in frequency in several countries. Only few studies, reporting contradictory results, have investigated the role of inhaled corticosteroids in the prevention of hospitalizations for asthma. Using a cohort of 2,059 hospitalized asthmatic patients between 5 and 54 yr of age, we estimated the effectiveness of inhaled corticosteroids in preventing a readmission to hospital for asthma as a function of the duration of therapy. The cohort was selected from the databases of Saskatchewan Health from 1977 to 1993. The rate ratio (RR) of a readmission for asthma varied with duration of regular therapy with inhaled corticosteroids. During the first 15 d of regular therapy, users of inhaled corticosteroids were as likely as nonusers of these medications to be readmitted for asthma with a RR of 1.2 (95% CI: 0.8-1.8). Subjects treated regularly with inhaled corticosteroids for at least 16 d and as long as 6 mo were 40% less likely to be readmitted for asthma (RR = 0.6; 95% CI: 0.4-0.9), while after 6 mo of regular treatment the protective effect disappeared (RR = 1.3; 95% CI: 0.7-2.4). We conclude that regular therapy with inhaled corticosteroids can substantially reduce the risk of a readmission for asthma after only 15 d of use. Confounding by severity appears as the most likely explanation for the disappearance of the beneficial effect after 6 mo of regular therapy.