Underdiagnosis and undertreatment of asthma in childhood

Asthma diagnosis and management in adults: is the risk of underdiagnosis and undertreatment related to patients' education levels?

To determine the relationship between patient education and the risk of underdiagnosis and undertreatment of asthma, a cross-sectional study of 500 (250 males and 250 females) adult attendees between 16 and 44 years of age was undertaken at five primary health care (PHC) centers in Al-Ain, United Arab Emirates. We used an Arabic translation of the European Community Respiratory Health Survey Screening Questionnaire. Asthmatics with higher levels of education had a significantly higher risk of underdiagnosis and undertreatment than asthmatics with less education. Doctors at PHC centers railed to diagnose 34.6% of the asthmatics with lower levels of education and 77.6% of the patients with higher levels of education. Eighty-five percent of the asthmatics with lower levels of education and 46.6% of the asthmatics with higher levels of education recognized that they had asthma. Thirty-eight percent of the asthmatics with lower levels of education and 83% of the asthmatics with higher levels of education were undertreated. It was found that 19% of the asthmatics with lower levels of education and 3% of the asthmatics with higher level of education were on prophylactic medication for asthma. We concluded that education level was related to underdiagnosis and undertreatment of asthma among adults between 16 and 44 years of age. People with higher levels of education have a higher risk of underdiagnosis and undertreatment than do those with lower levels of education. The factors that might be associated with these findings need to be explored in further studies.

Recognition of asthmatic symptoms in the pediatric age group

Asthma produces substantial morbidity in childhood. Under-diagnosis may lead to inappropriate treatment and prolonged periods of illness and absence from school. The results of a recent International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire study in Malta showed a higher prevalence of wheezy symptoms in the Central North Region. The present study was carried out to test the null hypothesis that there is no correlation between potential exposure to pediatricians (measured as pediatric private clinics/1000 childhood population/week) and percentage of children aged 13-15 years of age responding positively in the questionnaire to having had wheezy symptoms. A significant, positive correlation was found between potential exposure to pediatricians and percentage of children aged 13-15 years responding positively to having had wheeze in the previous year (p=0.009). A negative correlation was also found for severity of asthma (>12 attacks in the previous 12 months) and potential exposure to pediatricians (p=0.01). This is the first report of potential exposure to pediatricians influencing the regional incidence of asthma on a national basis. This skew may be caused by the greater exposure of pediatricians to patients with severe forms of asthma in a hospital setting, and hence a higher index of suspicion for the milder forms of the disease. Asthma may be less severe in regions where there are a greater number of pediatricians because of recognition of the condition with appropriate treatment and/or prophylaxis.

Issues and unmet needs in pediatric asthma

Asthma is common and becoming more so in childhood. Although mild asthma may incur low average annual costs per child, these estimates need to be viewed in the context of the very large numbers of affected individuals. Whereas asthma and wheezing illness in childhood had in the past been broadly subdivided into asthma (often associated with atopy) and wheezy bronchitis (wheeze only, with associated upper respiratory tract infection), this distinction was lost during the 1970s in view of the demonstrated underdiagnosis and undertreatment of symptomatic school-age children. The acceptance of asthma as a chronic inflammatory disease and evidence for airway remodeling and progressive deterioration in airway function in association with symptoms and atopy have led to earlier use of topical steroids at higher starting doses delivered by improved age-appropriate devices. Treating all children as if they were destined to become atopic asthmatics and at risk of airway remodeling may not be rational, particularly in those whose symptoms will subsequently resolve. However, there are as yet no screening tests which can clearly identify individuals at risk of long-term chronic airway inflammation and airway remodeling. The large number of infants and young children with current symptoms suggestive of asthma and in whom resolution is likely in the majority poses problems for the clinician in deciding the best initial therapy. There is an urgent need to develop simple and reliable measures that can identify the early manifestations of atopic airway sensitisation and to establish the place of early intervention with nonsteroidal drugs, including leukotriene antigonists.

Statewide adolescent asthma surveillance

We assessed the prevalence of diagnosed asthma, wheezing, healthcare utilization, and environmental triggers in children ages 13-14 years, and evaluated the feasibility of statewide asthma surveillance in North Carolina. A cross-sectional study (N = 1,596) was conducted using the International Survey for Asthma and Allergies in Childhood (ISAAC) questionnaire. Ten percent reported current diagnosed asthma. Nineteen percent reported wheezing symptoms with no diagnosis of asthma. Children with frequent wheezing were more likely to be poor, African-American, and female. Thirty percent of diagnosed asthmatics made 1 or more emergency room visits in the last year. Undiagnosed asthmatics were unmedicated. These results highlight the magnitude of the asthma epidemic in early adolescence, and illustrate that statewide surveillance using ISAAC is feasible.

[Cross-sectional study of school integration of asthmatic children in a general population sample]

AIMS

Asthma is one of the most frequently encountered chronic illnesses in children. The aim of the present study was to investigate the problem of integration of asthmatic subjects at school by assessing the reactions of parents and teachers, and also by considering the medical aspects.

POPULATION AND METHODS

A cross-sectional random study was carried out during autumn 1994 including 4,251 primary school children aged between five and 14 years, and including teachers from 188 classes and 26 schools in Grenoble and its inner suburbs. The first screening questionnaire was completed by the parents, and data on 3,799 children were obtained; from this, 191 currently asthmatic children were identified. One hundred and forty-six parents of the identified asthmatics subsequently answered a second questionnaire on the severity of the illness and its effects on school attendance and educational activities. The 186 teachers from the schools involved were interviewed about their knowledge of the disorder, and about what they knew of the treatment and management of asthmatic children in school.

RESULTS

It was found that the cumulative prevalence of asthma amounted to 7.6%, and that the prevalence over the previous 12-month period was 4.3%. Sixteen percent of the asthmatic children reported an asthma-associated school absence of more than six days during the six preceding months. In 45.2% of cases, physical exercise was responsible for an asthmatic attack, but premedication was used in only 21% of cases. Nine percent of the children had obtained a medical certificate which exempted them from participating in sports activities and physical exercise. Seventy-three percent of the parents had informed the teachers of their child's illness, but the information communicated was incomplete. It was found that the teachers did not have a thorough knowledge of the disorder, but that many of them (92.7%) would appreciate further information on the subject and on its management. Eighty-three percent of the teaching staff were unaware that the ministerial circular No. 93-248 of 22 July 1993 had been issued on the proposed management of chronic disorders at school, advocating a combined effort on the part of the parents, the child's physician, the school doctors and the teachers in setting up a concerted plan of action.

CONCLUSIONS

This study has demonstrated that the school integration of asthmatic children remains problematical both as regards treatment and the pursuit of indoor and outdoor school activities. Integration could be improved by using parent-doctor-teacher liaison forms, thereby maintaining closer communication regarding the child's needs. When this is not sufficient, an individualized asthma management plan could be introduced in collaboration with the parents, doctors and teachers, which might result in improved treatment and integration of asthmatic children in school.

Declining incidence of episodes of asthma: a study of trends in new episodes presenting to general practitioners in the period 1989-98

BACKGROUND

A study was undertaken to determine trends in the incidence of new episodes of asthma presented to general practitioners participating in the Weekly Returns Service of the Royal College of General Practitioners, comprising 92 practices with a registered population of approximately 680 000 persons well distributed throughout England and Wales. These practices monitor the morbidity presented at every consultation, distinguishing between new episodes of illness and ongoing consultations.

METHODS

Age specific weekly rates of new episodes of asthma (and of acute bronchitis) presenting to the general practitioners over the years 1989-98 were examined in four week blocks and analysed by multiple regression, separating secular from seasonal trends.

RESULTS

Quadratic trends in episodes of asthma were evident in each of the age groups with peaks in 1993/4. Corresponding analyses for acute bronchitis disclosed similar trends generally peaking in the winter of 1993/4. Mean weekly incidence data (all ages combined) decreased in all quarters since 1993. Regional analysis (North/Central/South) showed similar decreases.

CONCLUSIONS

There has been a gradual decrease in the incidence of asthma episodes and of acute bronchitis presenting to general practitioners since 1993. The trend of an increase before 1993 followed by a decrease cannot be explained by changes in the patterns of health care usage or diagnostic preference of doctors.

Intergenerational 20 year trends in the prevalence of asthma and hay fever in adults: the Midspan family study surveys of parents and offspring

OBJECTIVE

To estimate trends between 1972-6 and 1996 in the prevalences of asthma and hay fever in adults.

DESIGN

Two epidemiological surveys 20 years apart. Identical questions were asked about asthma, hay fever, and respiratory symptoms at each survey.

SETTING

Renfrew and Paisley, two towns in the west of Scotland.

SUBJECTS

1,477 married couples aged 45-64 participated in a general population survey in 1972-6; and 2,338 offspring aged 30-59 participated in a 1996 survey. Prevalences were compared in 1,708 parents and 1,124 offspring aged 45-54.

MAIN OUTCOME MEASURES

Prevalences of asthma, hay fever, and respiratory symptoms.

RESULTS

In never smokers, age and sex standardised prevalences of asthma and hay fever were 3.0% and 5.8% respectively in 1972-6, and 8.2% and 19. 9% in 1996. In ever smokers, the corresponding values were 1.6% and 5.4% in 1972-6 and 5.3% and 15.5% in 1996. In both generations, the prevalence of asthma was higher in those who reported hay fever (atopic asthma). In never smokers, reports of wheeze not labelled as asthma were about 10 times more common in 1972-6 than in 1996. With a broader definition of asthma (asthma and/or wheeze), to minimise diagnostic bias, the overall prevalence of asthma changed little. However, diagnostic bias mainly affected non-atopic asthma. Atopic asthma increased more than twofold (prevalence ratio 2.52 (95% confidence interval 1.01 to 6.28)) whereas the prevalence of non-atopic asthma did not change (1.00 (0.53 to 1.90)).

CONCLUSION

The prevalence of asthma in adults has increased more than twofold in 20 years, largely in association with trends in atopy, as measured indirectly by the prevalence of hay fever. No evidence was found for an increase in diagnostic awareness being responsible for the trend in atopic asthma, but increased awareness may account for trends in non-atopic asthma.

Underdiagnosis of asthma: is the doctor or the patient to blame? The DIMCA project

BACKGROUND

It is important to diagnose asthma at an early stage as early treatment may improve the prognosis in the long term. However, many patients do not present at an early stage of the condition so the physician may have difficulty with the diagnosis. A study was therefore undertaken to compare the proportion of patients who underpresented their respiratory symptoms with the proportion of underdiagnosed cases of asthma by the general practitioner (GP). A secondary aim was to investigate whether bad perception of dyspnoea by the patient was a determining factor in the underpresentation of asthma symptoms to the GP.

METHODS

A random sample of 1155 adult subjects from the general population in the eastern part of the Netherlands was screened for respiratory symptoms and lung function and the results were compared with the numbers of asthma related consultations registered in the medical files of the GP. In subjects with reduced lung function the ability to perceive dyspnoea was investigated during a histamine provocation test in subjects who did and did not report their symptoms to their GP.

RESULTS

Of the random sample of 1155 subjects 86 (7%) had objective airflow obstruction (forced expiratory volume in one second (FEV(1)) below the reference value corrected for age, length, and sex minus 1.64SD on two occasions) and had symptoms suggestive of asthma. Of these 86 subjects only 29 (34%) consulted the GP, which indicates underpresentation by 66% of patients. Of all subjects with objective airflow obstruction who presented to their GP with respiratory symptoms, 23 (79%) were recorded in the medical files as having asthma, indicating underdiagnosis by the GP in 21% of cases. Of the subjects with objective airflow obstruction who visited the GP with respiratory symptoms 6% had bad perception of dyspnoea compared with 26% of those who did not present to the GP in spite of airflow obstruction (chi(2) = 3.02, p = 0.08).

CONCLUSIONS

Underpresentation to GPs of respiratory symptoms by asthmatic patients contributes significantly to the problem of underdiagnosis of asthma. Underdiagnosis by the GP seems to play a smaller role. Furthermore, there are indications that underpresentation of symptoms by the patient is at least partly explained by a worse perception of dyspnoea.

Asthma after childhood pneumonia: six year follow up study

OBJECTIVE

To establish the long term cumulative prevalence of asthma in children admitted to hospital with pneumonia and to examine the hypothesis that some children admitted to hospital with pneumonia may be presenting with undiagnosed asthma.

DESIGN

Prospective study of a cohort of children previously admitted to hospital with pneumonia, followed up by postal questionnaires to their general practitioners and the children or their parents.

SETTING

General practices in southwest England.

PARTICIPANTS

78 children admitted to the Royal Devon and Exeter Hospital between 1989 and 1991 with a diagnosis of pneumonia confirmed on independent review of x ray films.

MAIN OUTCOME MEASURES

Any diagnosis of asthma, use of any treatment for asthma, and asthma symptom scores.

RESULTS

On the basis of a 100% response rate from general practitioners and 86% from patients or parents, the cumulative prevalence of asthma was 45%. A diagnosis of asthma was associated with a family history of asthma (odds ratio 11.23; 95% confidence interval 2.57 to 56.36; P=0.0002). Mean symptom scores were higher for all children with asthma (mean score 2.4; chi(2)=14.88; P=0. 0001) and for children with asthma not being treated (mean 1.4; chi(2)=6.2; P=0.01) than for those without asthma (mean 0.2).

CONCLUSIONS

A considerable proportion of children presenting to a district general hospital with pneumonia either already have unrecognised asthma or subsequently develop asthma. The high cumulative prevalence of asthma suggests that careful follow up of such children is worth while. Asthma is undertreated in these children; a structured symptom questionnaire may help to identify and reduce morbidity due to undertreatment.

[Relationship between respiratory syncytial virus bronchiolitis and asthma]

Data of the literature over the last 20 years indicate that infantile asthma, although heterogeneous, often appears following RSV bronchiotitis, especially when sufficiently severe to justify hospitalisation. The risk of developing episodes of wheezing (bronchial obstruction syndrome) over the following 2 to 3 years is higher than 50%, but estimations vary according to the authors. Functional disturbances (pulmonary distension, nonspecific bronchial hypperreactivity, hypoxia), with or without associated clinical symptoms, may be observed several months to several years after hospitalisation for bronchiolitis. On the other hand, mild bronchiolitis, and most of the recurrent expiratory obstructive syndromes with asymptomatic free intervals between episodes do not appear to carry a risk of functional sequelae. Children suffering from severe bronchiolitis usually develop a severe bronchial obstruction syndrome. In asthma, the percentage of IgE-dependent sensitization is less than 20% before the age of 4 years. The presence of positive skin tests and/or specific serum IgE directed against the usual allergens are associated with the persistence of asthma during the childhood. Similarly, the appearance of wheezing after the age of 3 years (or recurrence after this age) is associated with the persistence of asthma. Prospective studies of cohorts followed since birth show that pre-existing functional abnormalities can promote the appearance of bronchiolitis and bronchial obstruction syndrome. Asthma in infants comprises several phenotypes with very different prognoses.

What do parents of wheezy children understand by "wheeze"?

BACKGROUND

Reported wheeze is the cornerstone of asthma diagnosis.

AIMS

To determine what parents understand by wheeze.

METHODS

Two studies were undertaken: (1) Parents of clinic attendees with reported wheeze (n=160) were asked by questionnaire what they understood by "wheeze" and how they knew their child was wheezy. Responses were compared to definitions of wheeze in 12 epidemiology studies and their response options. (2) The extent of agreement of parents' reports (n=139) of acute wheezing in their children and clinicians' findings of "wheeze" and "asthma" was examined.

RESULTS

(1) "Sound" and "difficulty in breathing" were perceived central to "wheeze". "What you hear" was not selected by 23% (95% confidence interval (CI) 16-30%). "Whistling" was mentioned by 11% (CI 6-15%) but featured in 11 of 12 epidemiology questionnaires. (2) There was les than 50% agreement between parents' and clinicians' reports of wheeze and asthma.

CONCLUSIONS

Conceptual understandings of "wheeze" for parents of children with reported wheeze are different from epidemiology definitions. Parents' reports of acute wheeze and clinicians' findings also differ.

Assessing pediatric clinical asthma practices and perceptions: a new instrument

Over the past 20 years, the most substantial increases in prevalence, morbidity, and mortality of asthma have been observed among children aged 5-14 years. A survey instrument designed to measure clinical asthma management practices of primary care physicians was developed and evaluated. Study participants included 127 practitioners providing pediatric asthma care in inner-city communities in Baltimore, MD and Washington, DC. Study results found that the instrument assessed four separate dimensions of clinical assessments and five dimensions of physician perceptions. These dimensions should be considered in future research protocols and may be used to design tailored interventions to improve asthma care.

Serious childhood respiratory infections and asthma in adult life. A population based study. ECRHS Italy. European Community Respiratory Health Survey

BACKGROUND

A number of epidemiologic studies have tried to establish whether respiratory tract infections in early childhood cause obstructive pulmonary disease in adult life.

OBJECTIVE

To determine whether reported serious respiratory infection before the age of 5 years (SRI) is a significant risk factor for subsequent development of bronchial asthma and/or bronchial hyperresponsiveness in adults.

METHODS

We investigated a random population sample of 1,104 subjects (aged 20 to 40 years), participating in the European Respiratory Health Survey in Italy. Bronchial response to methacholine and answers to a standardized questionnaire were analyzed.

RESULTS

The prevalence of SRI (ie, a positive response to the question "Have you ever had a serious respiratory infection before the age of 5 years?") was significantly higher in the subjects with a positive family history of allergic diseases than in those with a negative one (O.R. 1.89; 95% C.I. 1.24 to 2.87, P < .01). No relationship was found between SRI and current adult asthma; however, asthma in the past was found in 20.5% of the SRI positive subjects and in 9.1% of SRI negative subjects (O.R. 2.47; 95% C.I. 1.47 to 4.15, P < .05). No difference in the response to methacholine and in FEV1, FEV1/FVC values was found between SRI positive and SRI negative subjects.

CONCLUSIONS

We suggest that a positive family history of atopy is associated with a significantly higher prevalence of SRI. Furthermore our results indicate that exposure to SRI is a risk factor for asthma in the past (ie, asthma in childhood and adolescence) but not for adult asthma or for the development of bronchial impairment in adult life.

Sensitivity and specificity of asthma definitions and symptoms used in a survey of childhood asthma

We compared the ability of definitions/symptoms of asthma to identify urban, elementary schoolchildren with physician-diagnosed asthma and bronchial hyperresponsiveness (BHR) post-exercise challenge. Definitions of asthma from the literature were compared, including American Thoracic Society (ATS) and British Medical Research Council (BMRC) definitions. Modified ATS had the highest sensitivity (77%), whereas BMRC had the highest specificity (99%). The most sensitive symptom was "wheeze with cold" (89%). The most specific symptoms were "medication required," and "breathing normal between attacks" (95%). Definitions and symptoms were poor predictors of BHR. Researchers can use these estimates in selecting and defining specific populations of children with asthma.

Prevalence and burden of illness for asthma and related symptoms among kindergartners in Chicago public schools

BACKGROUND

Asthma mortality rates in poor communities of Chicago are among the highest in the country. Possible explanations include increased asthma prevalence, increased severity, and suboptimal health care.

OBJECTIVE

To estimate the prevalence of asthma and asthma-related symptoms among inner-city kindergarten children, and to characterize their burden of illness, asthma-related health care access, and pharmacologic treatment.

METHODS

Cross-sectional survey of parents of kindergartners was conducted in 11 randomly selected Chicago elementary schools. A self-administered 16-item questionnaire was given to parents of kindergartners. Parents who reported doctor-diagnosed asthma or at least one of several key asthma-related symptoms were then interviewed with a supplemental questionnaire examining asthma-related health care and medication use.

RESULTS

Based on data from 638 children [mean age 5.7 (SD = 0.6) years], the prevalence of diagnosed asthma was 10.8%. Sixteen percent of the respondents reported that their child had wheezed in the past year. The prevalence of asthma-related symptoms unassociated with a diagnosis of asthma was 30.1%. The children with diagnosed asthma had evidence of a high burden of illness: over 40% were reported to have had sleep disturbance due to wheezing > or =1 to 2 nights/week and 86.6% reported acute care visits for respiratory symptoms in the past year. Self-reported access to medical care was high. Over 40% of the children with doctor diagnosed asthma were reported to have used a beta2-agonist in the preceding 2 weeks, and 12.2% used an inhaled anti-inflammatory.

CONCLUSIONS

These data suggest that asthma prevalence in school-aged children in inner-city communities may be higher than US estimates. The burden of illness experienced by these children is substantial. Also, a large proportion of children were reported to have respiratory symptoms consistent with asthma, and no asthma diagnosis, suggesting possible undiagnosed asthma. While measures of health care access appear to indicate that the majority of children with asthma experience no identified barriers to health care, there is evidence to suggest undertreatment.

The epidemiology of childhood asthma

Variability is the hallmark of childhood asthma. Conceptually defined as variable airflow obstruction, asthma affects individual children through a variety of clinical manifestations. Particular controversy surrounds the nature of wheezing in early infancy and its relationship to atopic asthma of later onset. Asthma prognosis is also highly variable and only to a limited extent predictable by clinical indicators in early childhood. Long-term follow-up studies suggest a complex pattern of remission and relapse as wheezy children are followed through adolescence into adult life. Similarly, the population burden of asthma is highly variable, both over time and between countries. The balance of evidence worldwide suggests a modest but sustained increase in the prevalence of asthma symptoms over the past three decades. Superimposed on this have been larger changes in diagnostic fashion and use of health services for childhood asthma in many countries. There is substantial international variation in the prevalence of asthma symptoms, and marked urban-rural differences have been reported from several African countries. These contrast with the more uniform distribution of the disease within industrialized countries, reflecting its ubiquity in affluent societies.

Asthma hospitalization rates and socioeconomic status in New York State (1987-1993)

This study examined the geographic distribution of asthma hospitalizations in New York State (NYS) and its association with socioeconomic status. Statewide asthma hospitalization data (1987-1993) were merged with 1990 census data by residential zip code. The asthma hospitalization rate increased in NYS from 1987 (2.54 per 1000) through 1993 (2.87 per 1000) and the increase is largely attributable to increases for children 4 years old and younger. The risk factors for asthma admission varied in different areas. However, rates of hospitalization because of asthma were generally higher in the zip codes areas with higher proportions of poverty, unemployment, poorly educated residents, African-Americans, and Hispanics.

Under-recognition of childhood asthma in Singapore: evidence from a questionnaire survey

In a recent study on the prevalence of childhood asthma and allergies using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires, 6238 Singapore school children in two age-groups, 6-7 years (n = 2030) and 12-15 years (n = 4208), were evaluated. Of the 1856 children who reported asthma-like symptoms (wheezing, exercise-wheezing, persistent nocturnal cough), 919 (49%) had not been diagnosed asthmatic. Of these undiagnosed children, 731 (39%) reported current symptoms of asthma. Under-recognition of asthma was more prevalent among those with persistent nocturnal cough and mild symptoms. In addition, the discordance between wheezing in the last 12 months and a diagnosis of asthma was significantly higher among the younger age-group (6-7 years), but exercise-induced wheezing was less recognized as a symptom of asthma among the older age-group (12-15 years). This study has shown that there is a substantial degree of under-recognition of asthma among school children in Singapore.

Asthma, wheezy bronchitis, and atopy across two generations

Although the prevalence of asthma has risen significantly during the last 30 yr, it is not clear whether this has occurred primarily in persons with a strong genetic predisposition to asthma and atopy or in other sections of the population. We have investigated outcomes in children of nuclear families selected through probands previously characterized by studies in 1964 and 1989 as having histories of persistent childhood onset atopic asthma, transient childhood wheezy bronchitis, and no respiratory symptoms or atopy. Children of wheezy bronchitic probands had a significantly better symptomatic outcome in adolescence, irrespective of the atopic status of the parent proband, than do children of either asthmatic or asymptomatic probands, suggesting that this may be a syndrome that shows familial aggregation and is distinct from asthma. Total serum IgE levels were significantly lower in children of nonatopic asymptomatic probands, including those with wheezing symptoms. In contrast children of nonatopic asymptomatic probands had an unexpectedly high prevalence of wheezing (33%), positive skin prick tests (56%), and positive specific serum IgE to common allergens (48%) that was similar to that found in children of atopic asthmatic probands. Our findings support the concept that wheezy bronchitis is a separate syndrome from atopic asthma. High total serum IgE levels within our population appear to be an important marker of genetic predisposition to atopy. Our data also suggest that much of the increase in asthma prevalence is associated with specific IgE sensitization and is occurring in persons previously considered to be at low risk of developing asthma or atopy.

One-year follow-up of young children hospitalized for wheezing: the influence of early anti-inflammatory therapy and risk factors for subsequent wheezing and asthma

We investigated the 1-year outcome of children hospitalized for wheezing, paying special attention to the effect of early anti-inflammatory therapy. In addition, we identified risk factors for recurrent wheezing and asthma. Eighty-eight children under 2 years old treated in the hospital for wheezing were followed for 1 year. Nebulized anti-inflammatory therapy was given for 16 weeks: 31 patients received budesonide, 29 patients cromolyn sodium, and 28 control patients received no therapy. The number of subsequent physician-diagnosed wheezing episodes was recorded. Four months of anti-inflammatory therapy did not significantly decrease the occurrence of asthma 1 year later; 45% of patients in the cromolyn group, 42% in the budesonide group, and 61% in the control group had asthma, defined as at least two bronchial obstruction episodes during the 1-year period after the original hospitalization for wheezing. An age over 12 months at the time of the initial bronchial obstructing episode [P=0.009, risk ratio (RR)=5.4, 95% confidence interval (CI)=1.53-19.31], failure to identify a viral cause (P=0.0003, RR=12.0, CI=3.16-45.40), history of wheezing (P=0.02, RR=14.6, CI=1.59-132.10), the presence of atopy (P=0.01, RR=5.3, CI=1.47-19.21), a family history of atopy (P=0.03, RR=3.6, CI =1.15-11.12), and serum eosinophil cationic protein (ECP) > or = 16 microg/L (P=0.005) were significant risk factors for asthma. We conclude that early anti-inflammatory therapy for 4 months does not significantly decrease the occurrence of asthma during the period of 1 year following hospitalization for the original episode of wheezing. Young children requiring hospital admission for wheezing during a respiratory tract infection are at increased risk of having subsequent asthma if they have wheezed previously, if they have atopy or a family history of atopy, if they have elevated serum ECP, if they are over 12 months of age at the original bronchial obstructive episode, and especially when viral studies are negative.

The impact of asthma and asthma-like illness in Seattle school children

The impact of asthma and asthma-like illness was measured in a population of 5-9-year-old Seattle public school children. Child health information was obtained from a survey of 1665 parents of first and second grade students to assess medical services use and impaired physical functioning among diagnosed asthmatics and those with current wheezing, defined as wheezing in the past 12 months without a diagnosis of asthma, relative to an asymptomatic population with neither condition. Relative to the asymptomatic population, the prevalence of respiratory-related activity limitation, and perception of poorer child health was larger among diagnosed asthmatics than children with current wheezing. However, the prevalence of sleep disturbances, school absences, medical services use, and parental concern over their child's health was similar for both the asthmatic and wheezing groups relative to the asymptomatic group. Also, in both symptomatic groups, a history of moderate or severe wheezing was associated with an increased prevalence of respiratory-related sleep disturbances and activity limitation. The similarity between the impact of diagnosed asthma and undiagnosed asthma-like illness suggests that the overall social and economic burden of asthma may be higher than previously estimated.

Asthma in non-inner city Head Start children

OBJECTIVE

Asthma is a significant cause of morbidity and mortality in children. The objective of this study was to determine whether the federal program Head Start in Dane County, Wisconsin, could be used as a mechanism to identify preschool-aged children with asthma.

DESIGN

Five-year, cross-sectional survey of parents with children enrolled in Head Start.

METHODS

Investigator-administered asthma screening questionnaire to parents of enrolling Head Start children in Dane County, Wisconsin.

MEASUREMENTS

Asthma prevalence and asthma-related health care use, including emergency department visits, hospitalizations, and medication usage, were measured using an asthma screening questionnaire developed by investigators.

RESULTS

Information was gathered on 2215 children. The prevalence of physician-diagnosed asthma in the screened children was 15.8%. Parental reports of physician-diagnosed asthma were validated in a subset of 133 children, with a 98.5% confirmation rate. Independent risk factors for asthma included male gender (relative risk, 1.4) and African-American ethnicity (relative risk, 1.4). Asthma-related morbidity was substantial with 26.7% of identified children hospitalized for asthma and 54.5% with an emergency department visit during their lifetime. The majority of children (46.4%) were treated with intermittent, quick relief medications (beta-agonists) alone, whereas only 6.1% were on daily, long-term controller medications.

CONCLUSIONS

Asthma screening through a Head Start program provides an effective means of targeting preschool-aged children from socioeconomic groups at high risk for asthma. Identification of children early in the disease course and those at high risk for asthma provides an ideal opportunity for the implementation of preventive and therapeutic interventions.

Atopy in children with otitis media with effusion

BACKGROUND

Contrasting data have been found on the prevalence of atopy in children with otitis media with effusion (OME). A major issue would be to determine whether screening for atopy should be recommended. Setting Centre for Study of Otitis Media with Effusion, Tabiano Terme, Parma, Italy.

OBJECTIVE

The purpose of this study was to investigate the relation of OME to atopy.

METHODS

The subjects were 172 children with OME and a control group of 200 children. The protocol included a questionnaire survey of diseases associated with atopy, a skin-prick test and a clinical evaluation of allergic symptoms and hypersensitivity to aeroallergens.

RESULTS

No significant difference between patients and control group was observed for family history of atopy or positive skin-prick test reactions. Symptoms associated with atopy occurred significantly more frequently in the group with OME (P<0.001), though only the presence of rhinitis or atopic eczema was significantly associated with OME.

CONCLUSIONS

Prevalence of positive skin-prick tests results is not enhanced in children with OME. Nevertheless, the association of OME with symptoms associated with atopy suggests that such concomitant diseases may play a part in the pathogenesis of the disorder. Children with allergic rhinitis or atopic eczema should be investigated by tympanometry for OME.

Population based study of risk factors for underdiagnosis of asthma in adolescence: Odense schoolchild study

OBJECTIVE

To describe factors related to underdiagnosis of asthma in adolescence.

DESIGN

Subgroup analysis in a population based cohort study.

SETTING

Odense municipality, Denmark.

SUBJECTS

495 schoolchildren aged 12 to 15 years were selected from a cohort of 1369 children investigated 3 years earlier. Selection was done by randomisation (n = 292) and by a history indicating allergy or asthma-like symptoms in subject or family (n = 203).

MAIN OUTCOME MEASURES

Undiagnosed asthma defined as coexistence of asthma-like symptoms and one or more obstructive airway abnormalities (low ratio of forced expiratory volume in 1 second to forced vital capacity, hyperresponsiveness to methacholine or exercise, or peak flow hypervariability) in the absence of physician diagnosed asthma. Risk factors (odds ratios) for underdiagnosis.

RESULTS

Undiagnosed asthma comprised about one third of all asthma identified. Underdiagnosis was independently associated with low physical activity, high body mass, serious family problems, passive smoking, and the absence of rhinitis. Girls were overrepresented among undiagnosed patients with asthma (69%) and underrepresented among diagnosed patients (33%). Among the risk factors identified, low physical activity and problems in the family were independently associated with female sex. The major symptom among those undiagnosed was cough (58%), whereas wheezing (35%) or breathing trouble (50%) was reported less frequently than among those diagnosed. Less than one third of those undiagnosed had reported their symptoms to a doctor.

CONCLUSIONS

Asthma, as defined by combined symptoms and test criteria, was seriously underdiagnosed among adolescents. Underdiagnosis was most prevalent among girls and was associated with a low tendency to report symptoms and with several independent risk factors that may help identification of previously undiagnosed asthmatic patients.

Treatment of childhood asthma. Options and rationale for inhaled therapy

Epidemiological studies suggest the prevalence of asthma is increasing, though some remain sceptical as to the magnitude or indeed the presence of an increase. However, despite improved diagnosis and the availability of the potent drugs now available there remains considerable respiratory morbidity associated with asthma. It is clear from a number of studies that failure to deliver drugs to the lungs when using inhaler devices is a factor contributing to this high level of morbidity. Failure of drug delivery may result from the prescribing of inappropriate devices, failure to use devices appropriately or failure to comply with a treatment regimen. For most of the currently available forms of asthma therapy there are significant advantages to be gained from administering them in aerosol form. The benefits to be derived from administering these drugs as an aerosol include a rapid onset of action for drugs such as beta-agonists and a low incidence of systemic effects from drugs such as beta-agonists and corticosteroids. Over the past 25 years our understanding of the nature of asthma has changed. Though this has been reflected in the emphasis on inhaled corticosteroid therapy in recent guidelines, it has not been reflected in the range of inhaler devices available. Manufacturers continue to place drugs such as corticosteroids in the same devices as short acting beta-agonists even though the requirements for these different drug classes are very different. It is likely that this contributes to suboptimal therapeutic responses with inhaled corticosteroids. However, the variability associated with current delivery systems is relatively small compared with the variability introduced by poor compliance. There is no work currently available to indicate how the use of cheap disposable devises which do not incorporate any form of positive feedback influence compliance with inhaled steroids. Optimising aerosolised drug delivery in childhood involves consideration of the class of drugs, the particular drug within a class but more importantly, the age and abilities of the child. Devices must be selected to suit a particular child's needs and abilities. Devices utilising tidal breathing are generally used such as spacing chambers or, less commonly these days, nebulisers. A screaming or struggling child, or failure to use a closely fitting mask, reduces drug delivery to the lungs enormously. Failure to respond to inhaled therapy in early childhood may be attributable to failure of drug delivery. Drug delivery in early childhood using current devices remains more an art than a science.

Monitoring of bronchial asthma

Assessment of asthma severity is important for disease management. Analysis of symptoms past and present, and previous and actual lung function measurements (including variability) is the usual method of evaluation and classification of asthma disease severity and activity. However, symptoms and lung function alterations are the result of pathophysiological processes including inflammation in the bronchial wall which, in chronic phases, precedes the clinical measurements, and are risk factors for disease progression and worsening. Tools for more precise determination of asthma disease processes in the airway wall would be of importance for prophylactic intervention to avoid chronic damage to the airways and acute worsenings to occur.

Achieving treatment goals for schoolchildren with asthma

OBJECTIVES

To identify problems in managing asthmatic children in school, which if dealt with would help reduce absenteeism and improve participation in school activities.

DESIGN

A survey by questionnaire to headteachers.

SETTING

Schools in Merthyr and Rhondda Cynon Taff, South Wales.

SUBJECT

Asthmatic schoolchildren in areas studied.

MAIN OUTCOME MEASURES

Facilities in schools to manage asthma, headteachers' perceptions of knowledge of asthma management by teachers, possession of written policies, and desire for further training.

RESULTS

There are 216 schools in the area studied, with 55,166 schoolchildren. A total of 191 (88%) headteachers returned the completed questionnaire. Five hundred and twenty seven (17%) children were reported absent from school during one term because of asthma, with an average of nine days of schooling lost per asthmatic child per term (range 2-16 days). Only 76 (40%) schools allowed children to be responsible for their inhalers, and 12 (6%) schools required parents to administer inhalers. In 115 (60%) schools, headteachers believed their staff were familiar with the management of asthma. A total of 174 (91%) headteachers expressed interest in further training.

CONCLUSION

This study highlights the need to train teachers and provide an agreed joint education and health policy on managing asthma in school.

Susceptibility of asthmatic children to respiratory infection

OBJECTIVE

A case-control study of patients with pneumonia was conducted to investigate whether wheezing diseases could be a risk factor.

METHODS

A random sample was taken from a general university hospital in S. Paulo City between March and August 1994 comprising 51 cases of pneumonia paired by age and sex to 51 non-respiratory controls and 51 healthy controls. Data collection was carried out by two senior paediatricians. Diagnoses of pneumonia and presence of wheezing disease were independently established by each paediatrician for both cases and controls. Pneumonia was radiologically confirmed and repeatability of information on wheezing diseases was measured. Logistic regression analysis was used to identify risk factors.

RESULTS

Wheezing diseases, interpreted as proxies of asthma, were found to be an important risk factor for pneumonia with an odds ratio of 7.07 (95% CI = 2.34-21.36), when the effects of bedroom crowding (odds ratio = 1.49 per person, 95% CI = 0.95-2.32) and of low family income (odds ratio = 5.59 against high family income, 95% CI = 1.38-22.63) were controlled. The risk of pneumonia attributable to wheezing diseases is tentatively calculated at 51.42%.

CONCLUSION

It is concluded that at practice level asthmatics should deserve proper surveillance for infection and that at public health level pneumonia incidence could be reduced if current World Health Organisation's guidelines were reviewed as to include comprehensive care for this illness.

Reduced forced expiratory flow in schoolchildren with respiratory symptoms: the Odense Schoolchild Study

In the present population-based study, spirometric lung function was assessed in symptomatic schoolchildren with and without asthma as compared to an asymptomatic reference group. The primary aim was to investigate if impaired lung function could be demonstrated in symptomatic schoolchildren, even in the absence of diagnosed asthma. Spirometry [forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), 50% of forced expiratory flow (FEF 50%) and 75% of forced expiratory flow (FEF 75%)] and anthropometric measures (standing height, weight, skin fold thickness, and length and circumference of the upper arm) were obtained from 1369 8-10-year-old children (81.5% of the eligible population) during the school year 1985-86. In 1321 of those subjects (96.5% of those examined), a self-administered questionnaire was completed. Thirty-five children belonging to ethnic minorities were excluded, thus 1286 subjects were included for further analysis. Point prevalences concerning asthma and respiratory symptoms (wheeze, cough and shortness of breath) were obtained. Thirty-seven children reported asthma and one or more asthma-like symptoms (symptomatic asthmatics), whereas 40 children denied having asthma, although claiming one or more asthma-like symptoms (symptomatic non-asthmatics). In both symptomatic groups, FEF 50% and FEF 75% were reduced relative to the reference group, the deficit being larger in the symptomatic asthmatics. FEF 75% was found to be more reduced than FEF 50%. FEV1 and FVC did not differ significantly between groups. It is concluded that only half of the schoolchildren with respiratory symptoms usually associated with the presence of asthma actually reported having this disease. These results demonstrate the presence of reduced lung function in symptomatic, reportedly non-asthmatic, children, suggesting clinically important underdiagnosis of asthma. More severe impairment of lung function was found in known asthmatics, also implying some degree of undertreatment.

[Factors related with the morbidity of asthma]

To determine the clinical situation, prescribed treatment and compliance in patients with asthma, and to identify the parameters that most influence control of the disease. We studied 335 asthma patients assigned to health centers. All were interviewed and respiratory gases were measured. Disease symptoms were recorded, along with treatment prescribed and inhalation method used. Compliance and inhaler use were assessed on a scale. Treatment appropriateness was evaluated against criteria of international consensus. Multiple regression analysis was used to identify the variables that most influenced control of asthma. Variables considered were age, sex, smoking, treatment appropriateness, inhaler technique, compliance with prescribed treatment and time since diagnosis. Disease was mild in 96 patients (28.7%), moderate in 111 (33.1%) and severe in 128 (38.2%). Treatment was appropriate in 118 (35.2%). Seventy-two (21.5%) used more drugs or higher doses than recommended. Prescribed treatment was inappropriate in 145 (43.3%). The inhalation technique was appropriate in 87 (27.5%) and inappropriate in 229 (72.5%). Ninety-four patients (28.1%) complied well with treatment and 241 (71.9%) were poor compliers. The variables that were significantly related to control of asthma were appropriate treatment and compliance. There is a high rate of morbidity due to asthma in the population studied. The percentage of inappropriate treatment is high, and compliance is low, these factors being the ones that most influence control of the disease.

Change in the use of and attitude to peak flow measurement among general practitioners in Northern Ireland between 1989 and 1994

In 1994 we repeated a study first performed in 1989 to assess the change in general practitioners' use of and attitudes to peak flow measurement. Of 232 general practitioners surveyed, 199 (86%) and 192 (83%) responded in 1989 and 1994 respectively. The percentage who reported having patients using domiciliary peak flow monitoring rose form 58.3 (95% confidence limits 51.4 to 65.2)% to 97.9 (95.9 to 99.9)%. The percentage who reported 'usually' using peak flow measurements for the diagnosis and management of asthma rose from 81.9 (76.5 to 87.3)% to 93.2 (89.6 to 96.8)% and from 83.3 (78.1 to 88.5)% to 95.8 (92.9 to 98.7)% respectively. An unchanged proportion took peak flow meters on house calls. General practitioners have become more aware of the potential of peak flow measurements but are still unlikely to have a meter available to assess patients seen at home. They are therefore likely to be ill-equipped to manage acute exacerbations of asthma in this setting.

The facilitator effect: results from a four-year follow-up of children with asthma

BACKGROUND

A long-term evaluation of the process and outcomes of primary and secondary care is required to establish whether audit facilitators can improve the care of childhood asthma.

AIM

To examine the long-term effect of an intervention by an audit facilitator on the management of children with asthma, and to investigate the implications for health service costs.

METHOD

A 4-year follow up was conducted of an intervention and control group totalling 2557 children aged 1-15 years from 12 general practices in the Tayside region. Primary care consultations, prescriptions, hospital contacts and health service costs 1 year before and 3 years after a facilitator visited practices were recorded. The facilitator encouraged the diagnosis and treatment of childhood asthma in the intervention group.

RESULTS

Favourable changes in consultation patterns, prescriptions and reduced hospital admissions seen during the intervention year did not persist in subsequent years. Two and three years after the facilitator visit the process and outcome of care was similar in both groups. The reduction in health service costs seen in the intervention group was equivalent to the cost of employing a facilitator.

CONCLUSION

The effect of a facilitator lasts only for the period of intervention. Enthusiasts will say that improving patient care without increasing health service costs justifies the widespread deployment of facilitators. Others more interested in long-term outcomes may disagree.

Improving care for minority children with asthma: professional education in public health clinics

OBJECTIVE

Recent studies have shown that lack of continuing primary care for asthma is associated with increased levels of morbidity in low-income minority children. Although effective preventive therapy is available, many African-American and Latino children receive episodic treatment for asthma that does not follow current guidelines for care. To see if access, continuity, and quality of care could be improved in pediatric clinics serving low-income children in New York City, we trained staff in New York City Bureau of Child Health clinics to provide continuing, preventive care for asthma.

METHODS

We evaluated the impact of the intervention over a 2-year period in a controlled study of 22 clinics. Training for intervention clinic staff was based on National Asthma Education and Prevention Program guidelines for the diagnosis and management of asthma, and included screening to identify new cases and health education to improve family management. The intervention included strong administrative support by the Bureau of Child Health to promote staff behavior change. We hypothesized that after the intervention, clinics that received the intervention would, compared with control clinics, have increased numbers of children with asthma receiving continuing care in the clinics and increased staff use of new pharmacologic and educational treatment methods.

RESULTS

In both the first and second follow-up years, the intervention clinics had greater positive changes than control clinics on measures of access, continuity, and quality of care. For second year follow-up data these include: for access, greater rate of new asthma patients (40/1000 vs 16/1000; P < .01); for continuity, greater percentage of asthma patients returning for treatment 2 years in a row (42% vs 12%; P < .001) and greater annual frequency of scheduled visits for asthma per patient (1.85 vs .88; P < .001); and for quality, greater percentage of patients receiving inhaled beta agonists (52% vs 15%; P < .001) and inhaled antiinflammatory drugs (25% vs 2%; P < .001), and greater percentages of parents who reported receiving patient education on 12 topics from Bureau of Child Health physicians (71% vs 58%; P < .01) and nurses (61% vs 44%; P < .05).

CONCLUSION

We conclude that the intervention substantially increased the Bureau of Child Health staff's ability to identify children with asthma, involve them in continuing care, and provide them with state-of-the-art care for asthma.

Interpretation of epidemiological surveys of asthma

Two particular issues make the interpretation of epidemiological studies in asthma problematic. The first is the lack of any clear definition of asthma. This is a perennial area of controversy. Thirty-eight years ago a Ciba Foundation guest symposium addressed this issue and suggested a solution. However, as J. G. Scadding, one of the participants of that symposium, pointed out after further consideration of the problem, what they had proposed was a description, not a definition. Since then, further attempts have been made but with little progress. They remain descriptive rather than definitive and have become, if anything, vaguer. The second problem has been the widespread failure to be precise about hypotheses or to define more precisely the hypothetical influences on asthma. Examples of this are the notions of 'inflammation' and 'atopy'. Standardization of methods for epidemiological studies of asthma is likely to provide a more rigorous framework for the comparison of results and the testing of hypotheses. Nevertheless, the development of such protocols should itself be seen as a hermeneutic device rather than an assertion of established knowledge.