Underdiagnosis and undertreatment of asthma in childhood

Wheeze, cough, atopy, and indoor environment in the Scottish Highlands

A questionnaire which included items on wheeze, cough, eczema, hay fever, and indoor environment, including parental smoking habits, pet ownership, heating and cooking methods, home insulation, damp, mould, and years lived in their houses, was given to 1801 children, aged 12 and 14 from the Highland Region in Scotland. Of the 1537 (85%) who replied, 267 (17%) reported current wheeze, 135 (9%) cough for three months in the year, 272 (18%) eczema, and 317 (21%) hay fever. There was no consistent relationship between respiratory symptoms and indoor environment although cough was associated with damp, double glazing, and maternal smoking. The prevalence of wheeze, cough, and atopy was higher in children who had lived in more than one house during their lifetime. These results suggest that increasing mobility of families in recent years may be more important in the aetiology of asthma than exposure to any one individual allergen or pollutant.

Deaths from asthma in Italy (1974-1988): is there a relationship with changing pharmacological approaches?

In this article we consider the relationship between asthma mortality rates, obtained from the Italian National Institute of Statistics (ISTAT), and the doses of all antiasthmatic drugs except systemic steroids sold in Italy in the years 1974-1988. The total asthma mortality rate showed three different trends: it decreased slowly until 1978 (period A); increased 10-fold from 1979 to 1985, rising from 0.30 to 4.17/100,000 (period B); and remained stable until 1988 (period C). More than half of the deaths in 1988 occurred in people 75 years of age or more. Men died more in the older age groups, while the mortality of women prevailed in the 35- to 54-year age group. In the 5- to 34-year age group the rate rose from 0.01 in 1978 to 0.21 /100,000 in 1986. Coding changes due to the 9th revision of the International Classification of Disease, adopted in Italy in 1979, probably increased the number of deaths being attributed to asthma in case of contemporary mention of bronchitis, a common diagnosis in older men, which showed the greatest increase in mortality. Increased prevalence and awareness of asthma may also have played a role. Although international comparisons strongly suggest undertreatment of asthma in Italy, the doses of anti-asthma drugs sold in Italy grew from 276 to 1,080 million from 1974 to 1985. During period B xanthine sales rose sevenfold and grew from 6.5 to 23.3% of the total doses, along with a twofold increase in beta 2-agonist and cromolyn sales. Period C was characterized by stable total doses (1155 million in 1988), with increases only in antiinflammatory and preventive drug sales. The increase in asthma deaths in Italy has been striking despite the contemporary rise in sales of all antiasthma drugs, particularly of beta 2-agonist metered aerosols and xanthine tablets. The increase in antiinflammatory and preventive drug sales may have contributed to the stabilization of asthma deaths during period C.

Infraglottic and bronchial infections

Concerns over infraglottic and bronchial infections have been a source of anxiety and lost sleep for many children, parents, and physicians. The annual incidence of lower respiratory tract infections in children younger than 6 years old exceeds 5 million in the United States. Despite the frequency of these infections, the often common and nonspecific clinical symptomatology, variable severity, and changing epidemiology over time all have contributed to our understanding and misunderstanding of these disorders.

Prevalence of possible undiagnosed asthma and associated morbidity among urban schoolchildren

OBJECTIVE

The extent to which urban children endure the symptoms and consequences of asthma without a physician diagnosis has not been well studied. Our objective was to obtain an estimate of the prevalence of possible undiagnosed asthma in a population of urban schoolchildren.

DESIGN AND METHODS

A population-based cross-sectional study was conducted in urban schoolchildren, grades 3 to 5. Undiagnosed asthma was defined as caretaker report of symptoms and/or bronchial hyperresponsiveness, defined as a 15% or greater drop in baseline forced expiratory volume in 1 second, after exercise challenge.

RESULTS

A total of 230 children (61% of those eligible) participated in the study. Forty children (17.4%; 95% Confidence interval (CI) = 12.5% to 22.3%) had reports of a physician diagnosis of asthma. Of these, 33 (14.3%; (95% CI = 9.8% to 18.9%) reported wheezing in the past 12 months. Among the remaining 189 eligible children, 11 (5.8%; 95% CI = 2.5% to 9.2%) met study criteria for undiagnosed asthma based on bronchial hyperresponsiveness (BHR). Another 16 (8.5%; 95% CI = 4.5% to 12.4%) met study criteria for undiagnosed asthma through modified American Thoracic Society symptom criteria. Overall, 27 children (27/189; 14.3%) fulfilled criteria for undiagnosed asthma. Children identified as having undiagnosed asthma were compared with children who had no BHR and no symptoms and who did not report a physician diagnosis of asthma (children without asthma). Children with BHR were more likely to have a report of allergies and eczema than children without asthma, odds ratios (OR) = 8.5 (95% CI = 2.4 to 30.7) and 6.4 (95% CI = 1.1 to 38.1), respectively. Children meeting symptom criteria were more likely to have a report of allergies, OR = 6.2 (95% CI = 2.0 to 19.1), and bronchitis, OR = 6.7 (95% CI = 2.0 to 22.4), and were also more likely to report sleep disruption, OR = 7.1 (95% CI = 2.3 to 21.8) and missed physical education classes, OR = 15.0 (95% CI = 4.8 to 46.7), compared with children without asthma.

CONCLUSIONS

We estimated a prevalence of 14.3% for possible undiagnosed asthma among urban schoolchildren, grades 3 to 5, through caretaker report of symptoms or BHR postexercise challenge. Children with undiagnosed asthma reported more atopic disease than children without asthma. In addition, children meeting symptom criteria for asthma reported more bronchitis, sleep disruption, and missed physical education classes than did those without asthma. These results suggest that rates of undiagnosed asthma may be high in this predominantly black school-age population.

Stability of respiratory symptoms in unlabelled wheezy illness and nocturnal cough

OBJECTIVE

To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren.

DESIGN

Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay.

SUBJECTS

The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children.

RESULTS

Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma).

CONCLUSIONS

Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.

Prevalence of asthma and wheeze in primary school children in northern Jordan

In order to determine the prevalence of asthma and wheeze in Northern Jordan, a questionnaire was distributed to 3540 school children aged 6-12 years in Irbid City. The completed questionnaires were returned by 3182 children, a response rate of 90%. The prevalence of physician-diagnosed asthma was 4.1%. Wheezing was reported by 8.3% of children. The male:female ratio was 2:1 for both conditions. In order of frequency, the triggering factors were respiratory tract infections, cold environment, exercise and dust. Statistically significant associations between wheezing (including asthma) and a family history of asthma, recurrent chest infections, eczema, allergic rhinicis and parental smoking were detected. Mode of delivery, breastfeeding and the presence of pets at home were not significantly associated. The prevalence of childhood asthma in Northern Jordan is similar to that in some countries of the developed world. Underdiagnosis may explain the relatively low prevalence of asthma found in this study population.

Influence of ethnic group on asthma treatment in children in 1990-1: national cross sectional study

OBJECTIVE

To examine the extent to which the prescription of drugs for asthma adhered to recommended guidelines in 1990-1 and to assess the influence of ethnic group on prescription.

DESIGN

Cross sectional.

SETTING

Primary schools in England and Scotland in 1990-1.

SUBJECTS

Children aged mainly 5-11 years. The representative samples included 10628 children. The inner city sample included 7049 children, 4866 (69%) from ethnic minority groups. For the prevalence estimation 14490 children were included in the analysis (82% of the eligible children). For the treatment analysis a subgroup of 5494 children with respiratory symptoms was selected.

MAIN OUTCOME MEASURES

Prevalence of respiratory symptoms and drugs commonly prescribed for asthma, method of administration, inappropriate treatment, and odds ratios to assess the effect of ethnic group on rate of prescription and method of administration.

RESULTS

Children with respiratory symptoms in the inner city sample were less likely to be diagnosed as having asthma. Of children with reported asthma attacks, those in inner city areas had a higher risk of not having been prescribed any drug for asthma (odds ratio 1.87 (95% confidence interval 1.26 to 2.77). Overall, 773 (75%) of these children had received a beta 2 agonist, 259 (25%) had received steroids, 148 (14%) had received sodium cromoglycate, and 194 (19%) had received no drug treatment in the previous year. When prescribed, beta 2 agonists were inhaled in 534 (69%) of cases, and this percentage was even lower in ethnic minority groups. Children of Afro-Caribbean and Indian subcontinent origin who had asthma were less likely to receive beta 2 agonists, and those from the Indian subcontinent were less likely to receive anti-inflammatory drugs. Antibiotics were less prescribed and antitussives more prescribed in children from ethnic minority groups than in white children.

CONCLUSION

In 1990-1 the risk of underdiagnosis and undertreatment of asthma was higher in children from ethnic minority groups. The implementation of indicators and targets to monitor inequalities in the treatment of asthma in ethnic groups could improve equity and effectiveness in the NHS.

Descriptive study of cough, wheeze and school absence in childhood

BACKGROUND

Respiratory symptoms such as cough and wheeze are associated with significant morbidity, including school absenteeism.

METHODS

A respiratory questionnaire was sent to the parents of all 5727 children aged 7-9 years of age registered with 95 general practitioners in the Southampton area to determine (a) the prevalence of asthma, cough and wheeze, (b) the effects of respiratory symptoms on school absenteeism, and (c) the use of anti-asthma medication.

RESULTS

A total of 4830 parents replied (response rate 86%). The 12 month prevalence of wheeze in the absence of cough was 5.5%, cough in the absence of wheeze was 10.0%, and 7.6% reported cough and wheeze; 15.2% of children had been diagnosed. Of the 4830 who replied, 12.7% were receiving bronchodilators, 0.6% xanthine derivatives, 1.7% sodium cromoglycate, and 4.1% inhaled corticosteroids. In all, 348 (7.2%) children had missed more than five days of schooling in the preceding year for respiratory symptoms, while 43 children (0.9%) had missed more than 20 days of schooling in the preceding year. Of the children who had missed more than five days of schooling, 43% reported cough and wheeze, 33% cough alone, and 16% wheeze alone in the preceding year. Compared with children who coughed, those who wheezed were significantly more likely to be diagnosed as asthmatic and to be receiving bronchodilators or inhaled corticosteroids.

CONCLUSIONS

In this study, cough was the most frequently reported symptom amongst children missing more than five days of schooling per year.

Prior diagnosis and treatment of patients with normal results of methacholine challenge and unexplained respiratory symptoms

OBJECTIVE

Previous research indicates that asthma has been underdiagnosed. However, we suspect that recent widespread attention to the underdiagnosis of asthma has led to an overdiagnosis of asthma in some settings. We therefore sought to examine prior diagnosis and treatment of patients referred to our facility and subsequently found to have no objective evidence of variable airflow limitation.

DESIGN

Retrospective chart review.

SETTING

Hospital-based asthma center.

PATIENTS

A referred sample of 263 patients in whom a methacholine challenge (MCC) was conducted after evaluation by our pulmonologists; complete medical histories were available.

MAIN OUTCOME MEASURES

Prior respiratory diagnoses, duration of treatment with asthma medications, and diagnosis following assessment by our pulmonologists in 175 patients with a provocative concentration of the substance causing a 20% fall in FEV1 (PC20) greater than 8.0 mg/mL and 88 with a PC20 of 8.0 mg/mL or less.

RESULTS

Of those with a PC20 greater than 8 mg/mL, a diagnosis of asthma or possible asthma prior to the challenge study was recorded by their primary care physician in 129 patients (74%). One hundred sixty of 172 patients (88%) with a PC20 greater than 8 mg/mL were diagnosed as not having asthma by our pulmonologists; 109 of 172 patients (62%) had been previously treated with asthma medication(s). The mean duration of asthma treatment was 25.9+/- 56.3 months, and there was no significant difference in the duration of treatment between this group and those who had a PC20 of 8 mg/mL or less. Most of those treated received inhaled beta2-agonists and inhaled corticosteroids. Approximately 61% received two or more classes of medications.

CONCLUSIONS

The misdiagnosis of asthma occurs commonly in the referral practice of a tertiary care asthma center. The more frequent use of objective pulmonary function testing in primary practice might reduce the problem of delayed diagnosis and inappropriate therapy for respiratory symptoms.

Risk of preschool asthma: incidence, hospitalization, recurrence, and readmission probability

Asthma is one of the most common chronic illnesses in childhood. Increases in hospitalization rates have occurred in several countries. The cumulative risk of asthma requiring medical attention was 11.7% for males and 7.0% for females aged 0-4 in Manitoba, Canada, for the cohort of children born in 1984/1985. The cumulative risk of hospitalization for males was nearly twice that of females (2.1% vs. 1.1%). Disease onset was most likely at age 1 year. The risk of rehospitalization or return physician visit for asthma increased significantly with the number of prior hospitalizations and physician visits, respectively, which may reflect both the persistence of asthma and the difficulty of developing an effective disease management strategy.

An asthma self-management program for children, including instruction in peak flow monitoring by school nurses

A randomized trial of an instructional method was conducted in which school nurses taught children asthma self-management principles and skills, including peak flow monitoring, in 20-min, individual sessions over an 8-week period. Thirty-six children participated. An intervention group of 18 children received the teaching sessions. A control group of 18 children received regular care by the nurses, but no teaching sessions. The sample included 64% boys, 69% African-Americans, and 69% Medicaid recipients. The average age of subjects was 10.2 years. The two groups were demographically similar, but despite random assignment, the control group had a significantly earlier age of onset of asthma and tended to have had more asthma attacks in the preceding year. These factors were statistically controlled in outcome analyses. Results of group comparisons showed no significant differences in the number of postintervention emergency room visits and days absent from school. However, nurses reported that children who practiced breathing exercises had less anxiety during exacerbations, and the nurses' knowledge of the children's baseline peak expiratory flow rates facilitated care of the children. Nurses expressed the opinion that the individual sessions with students might be useful in motivating them to participate effectively in later group sessions. The intervention was well accepted by students, parents, and nurses. We believe that this intervention is promising as a practical, low-cost approach to enhancing children's asthma self-management skills and warrants further testing in a larger sample, with the intervention conducted over a longer period.

Clinical evaluation of asthma

OBJECTIVE

The purpose of this article is to review the medical history and physical examination of the asthmatic patient.

DATA SOURCES

English references identified from relevant articles and book chapters, experts, and MEDLINE search, using "asthma," "physical diagnosis," and "medical history."

STUDY SELECTION

Clinical studies of the medical history or physical examination in subjects with respiratory disease were selected for review.

RESULTS

Symptoms such as wheezing, chest tightness and difficulty in taking a deep breath suggest asthma, while symptoms such as gasping, smothering or air hunger suggest alternative diagnoses. Symptoms of asthma correlate poorly with airway obstruction in one-third to one-half of asthmatic patients. Respiratory signs such as wheezing, breath sound intensity, forced expiratory time, accessory muscle use, respiratory rate and pulsus paradoxus correlate roughly with airway obstruction. However, clinicians disagree on the presence or absence of respiratory signs 55% to 89% of the time. Furthermore, physicians correctly predict pulmonary function based on history and physical examination only about half the time, and correctly diagnose asthma based on the clinical examination 63% to 74% of the time.

CONCLUSIONS

The medical history and physical examination are moderately effective in diagnosing asthma and estimating its severity. Objective measures of lung function are necessary for the accurate diagnosis of asthma.

Acute asthma: treatment and outcome of 2000 consecutive pediatric emergency room visits in Doha, Qatar

The case files of 2000 asthma episodes seen in our pediatric emergency room (PER) over a 2-month period were reviewed. Patients included 1429 males and 571 females with 66.2% < 48 months old. More than 60% of patients had been symptomatic for <24 hr and 88.5% had tried inhaled beta2-agonist before coming to the PER. In the PER, 57% responded to a single salbutamol aerosol and 35.5% responded to a combination of 2-3 salbutamol, IV hydrocortisone, and aminophylline drip < or = 6 hr. Only 7.5% were admitted to the hospital. Of the admitted patients, 82% had been symptomatic for > 24 hr and 60.6% were <4 years old.

Social factors associated with behavioral problems in children with asthma

The objective of this study was to describe the proportion of children with a behavior problem and examine which independent variables are associated with the presence of a behavior problem in a group of 392 inner-city children with asthma. Data on child asthma symptoms, medication use, health-care utilization, and school absences were obtained from the parent during a structured telephone interview. Included in the interview was a measure of behavior problems and social support questions. Children classified with a high level of asthma symptoms were more than twice as likely to experience a behavior problem than children classified with a low level of asthma symptoms (P = 0.002). Use of theophylline medication was not correlated with behavior problems (P = 0.45). Significant variables were low level of social support and high or moderate level of asthma symptoms. We have identified a group of children at risk for behavior problems, specifically in families that lack adequate social and financial resources.

Behavioral management of children's seizure activity. Intervention guidelines for primary-care providers

We present behavioral treatment guidelines, based on empirically established behavioral interventions, for pediatric paroxysmal disorders. The guidelines include affirming the disability and normalizing the role of the environment; teaching the child anticonvulsant coping behaviors; giving caregivers guidelines to encourage independent functioning; and involving teachers and other supervising adults in treatment. The guidelines were developed for economic feasibility, time efficiency, and easy execution in any primary-care clinic. A patient report demonstrates significant reduction in drug-refractory seizures in an 11-year-old girl by implementing the guidelines. Discussion is provided on effective implementation of the behavioral guidelines in the primary-care clinic.

Asthma management and mode of acquisition of inhaled bronchodilators

BACKGROUND

Controversy has existed about the benefits and disadvantages associated with the availability of inhaled bronchodilators over the counter (OTC).

AIMS

To compare sociodemographic features, use of preventive medications, use of medical services and control of asthma in adults who purchased inhaled bronchodilators OTC with those who purchased on prescription (script).

METHODS

A cross-sectional telephone survey of 772 adults 18 years and over who used inhaled bronchodilators for their asthma. Symptoms, asthma medications, and management practices were determined by a structured questionnaire administered by trained telephone interviewers.

RESULTS

Two hundred and thirty adults purchased their bronchodilator OTC and 542 on script. OTC purchasers were more likely to be male (OR: 1.5), have had tertiary education (1.5) and be in paid employment (2.8); they were less likely to report frequent symptoms (wheeze, nocturnal symptoms or EIA more than once a week) (0.71); were less likely to use preventive medications more than twice a day (0.57) and were less likely to have consulted a general practitioner in the previous year (0.38). However, poor control of asthma symptoms was evident in both OTC and script groups. Forty per cent of the OTC group who had symptoms more than two to three times a week and 34% of the script group were not using preventive medication.

CONCLUSIONS

Undertreatment and suboptimal management of asthma were apparent in both OTC and script groups.

Review of prescribed treatment for children with asthma in 1990

OBJECTIVE

To review treatment prescribed to asthmatic children in Great Britain during the 12 months after publication of the first guidelines and to assess effectiveness of prophylactic treatment.

DESIGN

Review of prescribing information from January 1990 to June 1991 in a representative sample of general practices in Great Britain with a Compufile/AAH Meditel computer.

SUBJECTS

17,846 children with asthma aged 4-17 years.

MAIN OUTCOME MEASURES

Numbers of children prescribed different asthma treatments; estimated use of inhaled beta agonists in those receiving prophylactic treatment.

RESULTS

From January to December 1990, 9,362 (52.5%) children were prescribed preventive treatments. 16,211 (90.8%) children were prescribed bronchodilators of some kind. 3,055 (17.1%) were prescribed sodium cromoglycate, and the proportion decreased significantly during the study (from 19.5% (95% confidence interval 18.6% to 20.4%) to 17.2% (16.4% to 18.1%), P < 0.001, in children aged 4-11 years and from 14.9% (14.0% to 15.9%) to 11.3% (10.4% to 12.2%), P < 0.001, in those aged 12-17 during January-July 1991). 6,952 (39.0%) were prescribed inhaled steroids, and the proportion increased during the study (from 35.1% (34.0% to 36.2%) to 44.1% (43.0% to 45.2%), P < 0.001, in children aged 4-11 years and from 38.7% (37.4% to 40.0%) to 44.1% (42.7% to 45.5%), P < 0.001, in those aged 12-17 during January-July 1991). Only 1,358 of the 9,362 children (14.5%) received sufficient repeat prescriptions to suggest that they might be taking the prophylactic treatment regularly. Among these children short acting inhaled beta agonists were being used on average four to eight times a day.

CONCLUSIONS

These results are useful baseline data for audit of the impact of published clinical guidelines, particularly in terms of reducing the need for short acting inhaled beta agonists with prophylactic treatment.

Education of parents about paediatric asthma: effects of a protocol on medical consumption

Asthma is a very common chronic disease among preschool children in primary health care. Research has shown that planned and systematic patient education positively affects the management of asthma by parents. This study focuses on the question of whether an asthma patient education protocol that is used by general practitioners (GPs) has an effect on medical care consumption. The treatment group consisted of 28 GPs, representing 47 asthmatic infants. The control group contained 18 GPs, representing 38 patients. Data were collected from medical records (with a written instrument) for a 12-month period preceding and after the intervention period in which the education protocol was tested. Results indicated that sociodemographic variables and pretest data on asthma severity and medical care utilization were largely comparable for patients in both study groups. Furthermore, the treatment group showed a significantly greater decrease than the control group from pre- to post-test measurement in the number of contacts with the GP and the number of emergency visits to the physician's office.

Do lower respiratory tract infections in early childhood cause chronic obstructive pulmonary disease?

The hypothesis that lower respiratory tract infections (LRTI) in early childhood lead to chronic obstructive pulmonary disease (COPD) in late adult life has been difficult to test. However, a unique opportunity arose when records were discovered in the counties of Hertfordshire and Derbyshire, England, that contained information about childhood LRTI recorded 60 to 70 years ago. The lung function of some men still living in these counties was examined. In Hertfordshire men, bronchitis or pneumonia in infancy was associated with reduced mean FEV1, adjusted for age and height. In Derbyshire men, pneumonia before 2 yr of age was associated with a large and highly significant reduction in mean FEV1, adjusted for age and height. These findings were independent of smoking and social class. These data support a causal relationship between LRTI in early life and subsequent COPD.

The Yentl syndrome in childhood asthma: risk factors for undertreatment in Swiss children

Recent prevalence data for childhood asthma in Switzerland suggest a substantial underdiagnosis which seems to be more pronounced in girls. We further analysed our data trying to specify risk factors for underdiagnosis and undertreatment. Our special interest was focused on female sex as there is evidence for a sex-dependent diagnosis and treatment of chronic disease in adults, called the Yentl syndrome. The data are derived from a parent completed questionnaire survey of a stratified cluster sample of schoolchildren aged 7, 12, and 15 years. Besides the 12 months prevalence of asthma symptoms and bronchodilator treatment, the lifetime prevalence of an asthma diagnosis was noted. With a response rate of 97%, a total of 4353 completed questionnaires were analysed. While age was not associated with undertreatment (except for exercise-induced symptoms in adolescents), the lack of a formal diagnosis of asthma and atypical asthma symptoms other than wheeze such as chronic night cough were confirmed as significant risk factors for undertreatment. Of all boys reporting asthma symptoms 31% received bronchodilator treatment compared with only 15% of the symptom-reporting girls (P < 0.001). For all particular asthma-related symptoms (except wheeze), significantly more boys than girls (approximately double) received treatment. The physiological and psychological bases for these findings are discussed and suggest that gender is an important risk factor for underdiagnosis and undertreatment of asthma. Our research indicates that the Yentl syndrome may exist for childhood asthma.

Asthma and allergic rhinitis among Finnish adolescents in 1977-1991

OBJECTIVES

To study whether asthma and allergic rhinitis had increased from 1977 to 1991 and if so, in which subpopulations; to study if structural changes of the society or change in the genetic susceptibility of the population could explain the increase.

DESIGN

Cross-sectional surveys with mailed questionnaires in 1977, 1979 and 1991, data from 1977 and 1979 combined; national mortality statistics.

SETTING

Finland.

SUBJECTS

A nationwide sample of 12-, 14-, 16- and 18- year-olds. Sample sizes were 4335 and 3059, response rates 88% and 77%. Mortality statistics from 1958 to 1990.

MAIN OUTCOME MEASURES

Point prevalence rate (%) of self-reported, physician-diagnosed asthma and allergic rhinitis, susceptibility of the population measured by probability of respiratory death.

RESULTS

Prevalence of asthma was 1.0% in 1977-1979 and 2.8% in 1991, that of allergic rhinitis 5.0% and 14.9%. Logistic regression analysis showed that the increase did not differ in socio-demographic subgroups or parents' smoking groups and that changes in the distribution of socio-demographic variables did not explain the difference either. Respiratory deaths in ages 0-4 were fewer in the birth cohorts measured in 1991.

CONCLUSIONS

Physician-diagnosed asthma and allergic rhinitis increased three-fold among Finnish adolescents in 1977-1991. Factors which explain the increase affected all subgroups similarly. Such factors could be changes in diagnostic practices and indoor air quality. Increased susceptibility could explain only a small part. It is likely that a major part of this considerable increase is real.

Asthma treatment, perceived respiratory disability, and morbidity

An entire school year of 8-9 year old schoolchildren in Sheffield were surveyed using the core questions of the international study of asthma and allergies in childhood in order to assess the morbidity associated with diagnosed asthma. Of 5321 children surveyed, replies were obtained from 4539 (85.3%). A current diagnosis of asthma was reported in 466 (10.3%), and a further 6.4% reported symptoms compatible with significant undiagnosed asthma. A validated questionnaire was used to assess symptoms and perceived disability in 336 (72.1%) of the children with diagnosed asthma. One third reported symptoms every day or most days, while 15.3% reported frequent nocturnal symptoms. There was no significant difference in reported symptoms between those receiving inhaled steroids, sodium cromoglycate, or no prophylaxis. Despite this, parents of children receiving inhaled steroids perceived more disability, and worried more about their children's health. It is concluded that perceived symptoms and morbidity are high in children with diagnosed asthma, and speculate that level of treatment is determined by parental tolerance of symptoms as much as by the symptoms themselves.

The role of measuring forced expiratory volume in one second in determining therapeutic changes made in an asthma clinic in general practice

In order to determine whether spirometric measurements in a primary care asthma clinic added useful information to symptom assessment and peak flow recordings, a retrospective audit of manual case records was conducted on patients attending an urban general practice asthma clinic. Sixty-three patients were identified in whom 108 increases in treatment at the clinic had been recorded and the associated determinants of these changes were extracted from their case notes. Therapeutic changes associated with the following determinants alone were only found in single instances: presence of or changes in symptoms, inhaler technique deficiency, forced expiratory volume in 1 s (FEV1) less than 75% of the predicted value and peak expiratory flow (PEF) rate less than 75% of the predicted value. In no instance did changes in FEV1 or in PEF alone occur. The addition of spirometric measurements in this sample of patients only made an obvious difference to decision-making in four instances (4%). Therefore, the role of spirometers in the management of asthma in general practice needs further consideration and clarification on a wider scale before limited resources, whether in terms of time or money, are committed to their use.

The relationship between respiratory symptoms and bronchial hyperresponsiveness in a population-based sample of adolescents and young adults

OBJECTIVES

to study the relationship between chronic respiratory symptoms and bronchial hyperresponsiveness (BHR) in adolescence and young adulthood and to assess the possible predictive value of these symptoms for BHR.

METHODS

a cross-sectional analysis: in a population sample of 551 subjects aged 10-23 years, data collected with a standardized questionnaire on respiratory symptoms were compared with the results of a histamine challenge test.

RESULTS

43% of the subjects reported one or more chronic respiratory symptoms; of these subjects 54% did not show BHR. Forty-two per cent of the subjects had a PC20 < or = 8.0 mg ml-1 histamine, of which 53% reported no chronic respiratory symptoms. Wheezing and breathlessness were related to the level of BHR, but only 'breathless when walking on the flat' was independently related to BHR; however, its predicted value for BHR was negligible.

CONCLUSIONS

in adolescents and young adults the relationship between chronic respiratory symptoms and BHR is incomplete. A standardized questionnaire on respiratory symptoms does not provide adequate information to discriminate between those with and without BHR.

Knowledge of asthma and its management in newly qualified doctors in Accra, Ghana

This study assessed first-year doctors' (House Officers) knowledge of asthma at the Korle-Bu Teaching Hospital. Seventy-two out of 80 doctors answered 32 questions on various aspects of asthma. Many of these doctors managed between one to three asthmatics per week. Few, however, did so by acceptable standards. In assessing the severity of asthma, 88% looked for cyanosis, 69% looked for pulsus paradoxicus and 63% looked for a fast pulse rate. Only 63% considered the measurement of peak expiratory flow useful. Ninety-four percent used intravenous aminophylline, 82% intravenous hydrocortisone and 74% oxygen as the drug of choice for acute severe asthma. In moderate forms of acute asthma, 54% used salbutamol inhaler or intravenous aminophylline, 28% oxygen, 15% steroid inhaler and 14% oral prednisolone. Nebulized bronchodilators are not well known for use in either severe or moderate asthma and only 19-21% of doctors had prescribed their use. In chronic asthma, 55-65% of respondents prescribed bronchodilators compared to 19-35% who gave anti-inflammatory drugs. These results reveal insufficient knowledge of the pathophysiology of asthma, the use of standard drugs in asthma therapy and international guidelines for the management of asthma. The results also show that the pragmatic constraints which exist in developing countries preclude the adoption of international guidelines without local modification.

Pet ownership in the UAE: its effect on allergy and respiratory symptoms

The aim of this paper was to study the effect of pets and other domestic animals on bronchial asthma among United Arab Emirates (UAE) schoolchildren aged 6-14 years. A cross-sectional study of 850 schoolchildren living in both urban and rural areas (average age 9.36 +/- 2.11 years, 46.8% boys and 53.2% girls) was conducted using self-administered questionnaires between October 1992 and May 1993. Prevalence rate for asthma, rhinitis, wheeze, cough, and eczema in children from families with and without animals were investigated. A total of 40.7% of families studied were found to keep animals in their homes. Children from families with animals were found to have a significantly higher prevalence rate of respiratory symptoms than those without. The prevalence rate for asthma in children with animals was found to be twice that of children without (RR: 2.03; 95% CI: 1.40-2.95). The risk of having chronic cough (RR: 1.93; 95% CI: 1.21-3.10), breathlessness/chest tightness (RR: 2.53; 95% CI: 1.59-4.02), chronic wheeze (RR: 2.10; 95% CI: 1.20-3.67), allergic rhinitis (RR: 1.53; 95% CI: 1.17-2.00) was significantly higher in children with animals than in children without. Similarly, the risk of having eczema (RR: 2.55; 95%, CI: 1.74-3.75) was significantly higher among children with animals than among those without. Overall, there was a highly statistically significant difference in the prevalence of asthma, wheeze, nocturnal cough, eczema, and rhinitis between children in families with animals and those without (p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of asthma and asthma-like symptoms in young adults living in three east Anglian towns

BACKGROUND

The European Community respiratory health survey is examining the prevalence of asthma and risk factors for asthma.

AIM

As part of this multinational survey, a study was undertaken to determine the prevalence of asthma and asthma-like symptoms in young adults living in Cambridge, Ipswich and Norwich using a postal questionnaire.

METHOD

A previously validated symptom questionnaire was sent to 2500 men and 2500 women aged 20-44 years living in and registered with a general practitioner in each of the three towns.

RESULTS

In total, approximately 9000 adults responded. The prevalence of symptoms suggestive of asthma was found to be similar in the three towns. Of respondents, 8% reported having been woken by an attack of shortness of breath at some time in the last 12 months, higher than previously reported. Five per cent reported having had an asthma attack.

CONCLUSION

General practitioners wishing to examine asthma prevalence in their own practice population could use a similar methodology.

The beta 2-agonist controversy. Observations, explanations and relationship to asthma epidemiology

Links between frequent use of inhaled beta 2-agonists and morbidity and mortality from asthma appear probable. Two mortality epidemics followed the marketing of potent inhaled adrenergic agents. Case-control studies in New Zealand linked mortality with prescription of fenoterol, especially in severe asthma. A Saskatchewan case-control study confirmed an association of mortality with fenoterol, and also with frequent use of salbutamol (albuterol). Cardiac effects of beta 2-agonists do not cause mortality, but frequent use of these agents may increase the chronic severity of asthma, hence increasing the number of asthmatic patients at risk of death in an acute attack. Frequent use of beta 2-agonists may reduce lung function, increasing airway responsiveness, and impair control of asthma, despite use of inhaled corticosteroids. Mechanisms for this effect may include tachyphylaxis to nonbronchodilator effects, increased responsiveness to allergen, interaction with corticosteroid receptors, altered mucociliary function, differential effects of enantiomers, and masking of symptoms by beta 2-agonist use. The withdrawal of fenoterol from New Zealand in 1990 was associated with a substantial decline in morbidity and mortality. Overall, the evidence suggests that frequent use of inhaled beta 2-agonists has a deleterious effect on the control of asthma. Epidemics of mortality are explained by an increase in chronic severity of asthma following introduction of more potent beta 2-agonists. While beta 2-agonists remain essential for relief of breakthrough symptoms, long term use, particularly with high doses of potent agents, appears to be detrimental.

What do pediatricians in training know about the correct use of inhalers and spacer devices?

Most patients with asthma in the United States are cared for by nonspecialist physicians. Because inhaled medications are the mainstay of asthma therapy and their successful use requires both practical skills and theoretic knowledge, we wondered how much nonspecialist physicians know about the use of metered-dose inhalers and spacer devices. Fifty pediatricians in training were interviewed individually. Practical knowledge was assessed by asking each to demonstrate correct use of a placebo inhaler and a spacer device (Inspirease [Key Pharmaceuticals, Inc., Miami, Fla.] and Aerochamber with mask [Monaghan Medical Corp., Plattsburgh, N.Y.]). Of the seven recommended steps for use of metered-dose inhalers, the residents demonstrated an average of 3.8 steps correctly. The most common errors included not shaking the metered-dose inhaler before use (18% of residents correct) and insufficient breath holding (28% correct). In testing spacer use, the most common errors included not shaking the canister (16% correct) and incorrect number of activations and inhalations (12% correct). Many residents were not familiar with correct assembly of the spacer (48% correct). Theoretic knowledge of metered-dose inhaler and spacer use was evaluated by a written questionnaire. The most common deficiencies in theoretic knowledge related to the purpose of slow inspiration and breath holding. Most of the participants had been treating children with asthma and had prescribed metered-dose inhalers (45 of 50, 90%) and spacer devices (76%) in the past.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of asthma and wheeze in the Highlands of Scotland

To establish the prevalence of asthma and wheeze in 12 year old children in a region with low background pollution levels, a population of children resident in the Highland Region of Scotland was studied by questionnaire supported by objective data. A respiratory questionnaire was distributed to the parents of 1919 children aged from 12-13 years and attending secondary schools in the educational divisions of Lochaber, Ross and Cromarty, and Inverness including Skye in Highland Region to ascertain history of wheeze and parental awareness of a diagnosis of asthma. Peak expiratory flow (PEF) measurements were carried out before and after a standardised exercise test. Ozone levels were noted. Questionnaires were completed by 1825 parents (95% of those invited) and 1702 (93%) of those returning questionnaires took part in the exercise test. The overall prevalence of reported asthma was 14% and wheeze 25%. Defined as a fall in PEF of more than 15% with exercise, the overall prevalence of exercise induced bronchospasm was 9%. In Skye the prevalence of reported asthma was 17%, wheeze 28%, and exercise induced bronchospasm 30%. There were no significant differences between areas for reported asthma or wheeze. There was, however, a highly significant difference between areas for exercise induced bronchospasm, most of which was accounted for by the very high incidence in Skye, which is one of the most rural of the areas studied. The results of this study do not support the hypothesis that asthma is commoner in urban than rural areas, whether we compare the Highlands with the rest of the UK or areas within the Highlands, or whether we examine reported symptoms or exercise induced bronchospasm. The results do not support an association between atmospheric pollution and the prevalence of asthma.

Bronchial hyperreactivity and history of wheezing in children

The objective of this analysis was to determine the relationship between wheezing at different age groups in children and the prevalence of bronchial hyperreactivity at the age of 10. A population-based cross-sectional study was conducted in Leipzig and the region around Halle in Germany. Of 3105 10-year-old children, 2658 questionnaires (85.6%) were returned. In addition 2279 (73.4%) pulmonary function tests were performed before and after cold air challenge. 658 children (24.8%) had recurrent wheezing during their lifetime. In 579 children the individual time course could be evaluated (46 children with and 533 without a physician-confirmed diagnosis of asthma). Wheezing began most frequently in the 1st year of life (44.1% of all wheezing children) with the highest annual prevalence in the 3rd year (71.0% of all wheezing children). Wheezing which started in the first 2 years of life, had disappeared in most of the children by the age of 10. However, if wheezing began later than the 3rd year it was more persisting. Bronchial hyperreactivity measured after cold air challenge was higher in the group with recurrent wheezing (24.1%) than in the group without wheezing (18.8%, P = 0.004).

CONCLUSION

Wheezing is a very common symptom in childhood and only partly associated with later bronchial hyperreactivity. On the other hand, asthma is often not diagnosed despite bronchial hyperreactivity and many years of wheezing.

Recognition and crisis management of asthma in schools

Under-reporting of asthma and inappropriate management at school can hamper a child's academic progress. The aim of this study was to assess asthma reporting and crisis management, following implementation of a Primary School Asthma Programme. The intervention covered 12 primary schools with 5093 students in an area of high unemployment with a large proportion of the community from a non-English background. The programme included School Asthma First Aid Kits, training workshops for school staff and individual Crisis Management Plans for students with asthma. Registration of students with asthma at school increased from 6.2% before the intervention in 1989 to 12.7% in 1992. School Asthma Crisis Plans were completed appropriately by the child's doctor and parents and returned by 68% of the students with asthma. Teachers' asthma knowledge and confidence with the management of acute asthma at school improved following asthma education workshops. It was concluded that asthma reporting and acute crisis management of asthma at school can be achieved by a programme undertaken by school medical services.

Asymptomatic bronchial hyperreactivity and the development of asthma and other respiratory tract illnesses in children

BACKGROUND

It is not clear whether asymptomatic bronchial hyperresponsiveness (BHR) in children is a risk factor for the subsequent development of asthma. A longitudinal study was conducted to determine the predictive value of BHR for the development of asthma in a primary care patient population.

METHODS

A standard free running asthma screening test (FRAST) was applied to 956 schoolchildren aged between 4 and 11 years in 1985. Peak expiratory flow (PEF) rates were measured before hard running for six minutes and following a three minute rest period. Children with a fall in PEF of more than 15% were labelled as having a positive FRAST. Clinical data from the patients' notes and from symptom questionnaires were compared with age and sex matched controls for children known to have asthma, and for those with a positive FRAST but no asthma (BHR group). Over the ensuing six years to 1991 further clinical data were gathered to compare the development of asthma and other diseases of the airways in both the BHR groups and their controls.

RESULTS

Of the 956 children exercised in 1985, 60 who were not known to have asthma had an abnormal test. Of the 55 of these studied in 1991, 32 (58%) had developed asthma. The sensitivity of a positive FRAST for the development of asthma was 58%, its specificity 97%, and positive predictive value 72%. Hay fever, eczema, otitis media, "bronchitis," and family history of atopy also occurred more commonly in this group.

CONCLUSIONS

Asymptomatic BHR, as shown by exercise challenge, can predict the development of clinical asthma. This study has also shown a relation between BHR, asthma, and other diseases of the airways, notably upper respiratory tract infection, "bronchitis," and otitis media.

Assessing fullness of asthma patients' aerosol inhalers

BACKGROUND

The importance of regular medication in order to control asthma symptoms is recognized. However, there is no accurate mechanism for assessing the fullness of aerosol inhalers. The contribution to asthma morbidity of unexpectedly running out of inhaled medication is unknown.

AIM

A study was undertaken to determine how patients assess inhaler fullness and the accuracy of their assessments, and to evaluate the floatation method of assessing inhaler fullness.

METHOD

An interview survey of 98 patients (51% of those invited to take part), using 289 inhalers, was completed at one general practice in Hampshire.

RESULTS

One third of participants said they had difficulty assessing aerosol inhaler fullness and those aged 60 years and over were found to be more inaccurate in assessing fullness than younger participants. Shaking the inhaler to feel the contents move was the commonest method of assessment. When placed in water, an inhaler canister floating on its side with a corner of the canister valve exposed to air indicates that the canister is less than 15% full (sensitivity 90%, specificity 99%).

CONCLUSION

Floating a canister in water provides an objective measurement of aerosol inhaler fullness. Providing the method is recommended by the aerosol inhaler manufacturer, general practitioners should demonstrate the floatation method to patients experiencing difficulty in assessing inhaler fullness.

Wheeze in preschool children and its relation with doctor diagnosed asthma

OBJECTIVE

To describe the characteristics of wheeze and its relation with doctor diagnosed asthma in children aged 5 years and under.

DESIGN

Questionnaire survey of population based random sample of children registered on Leicestershire Health Authority's child health index for immunisation; questionnaire completed by parents.

SUBJECTS

1650 white children born in 1985 to 1989 who were surveyed in 1990.

MAIN OUTCOME MEASURES

Age distribution, severity, precipitants, seasonal characteristics, and diurnal variation of wheeze, family history of asthma/atopy, and their association(s) with doctor diagnosed asthma.

RESULTS

There were 1422 replies (86.2%). Two hundred and twenty two (15.6%) were reported to have wheezed and of these 121 (8.6%) had formally been diagnosed as having asthma. More than 80% of the former had recurrences of wheeze and 40% (72) had three or more episodes in the preceding 12 months. Age, number of episodes per year, the severity of shortness of breath with attacks, and precipitants other than colds were the major factors determining the probability that a wheezy child will be diagnosed as having asthma. The data also suggest that despite the strong association of symptom based criteria with the label asthma, asthma was not diagnosed by these same severity criteria in one quarter of cases.

CONCLUSIONS

Clinical and physiological follow up studies of children identified as asthmatic by the above criteria during the preschool years should validate or refute the predictive value of these measures of wheeze severity.

Prevalence of asthma among Emirates school children

The aim of this study was to determine the prevalence of asthma among United Arab Emirates school children aged 6-14 years. A cross-sectional study of 850 school children living in both urban and rural areas (average age 9.36 +/- 2.11 years, 46.8% boys and 53.2% girls) was conducted using self-administered questionnaires between October 1992 and May 1993. The population sample had a high prevalence rate of diagnosed asthma (13.6%), breathlessness or tightness in chest (9.7%), allergic rhinitis (22.9%), and nocturnal cough (8.9%). Allergic rhinitis was the most frequently seen respiratory illness when compared to other respiratory symptoms. The frequency of asthma, allergic rhinitis and eczema among parents reflected the same pattern as that seen in the children. Prevalence rate of asthma was not significantly higher in fathers (5.9%) than in mothers (5.3%). The differences between the sexes were not significant in any of the age group studied for any of the allergic conditions, except for diagnosed asthma in which the prevalence rate in males was significantly higher than that in females. On the whole, the prevalence rate of all the conditions increased with age. But the frequency of allergic rhinitis symptoms was significantly higher in mothers (16%) than in fathers (10.8%). These results are consistent with those obtained in neighbouring gulf countries and are higher than those of some developed countries, but the differences are not statistically significant.

Screening for asthma in children

The primary health care team is at the forefront of asthma management and there is evidence of improved delivery of care via nurse run, audited, general practice clinics. However, hospital admissions for asthma continue to rise. Screening for childhood asthma would appear to have advantages for patient care. This review looks critically at the literature that addresses important issues in screening for childhood asthma, including the problem of defining asthma, its prevalence rate and the importance of dealing with asthma as part of a spectrum of illnesses of the upper respiratory tract. The fundamental principles of screening in relation to asthma are addressed, and five screening procedures are described and debated. Questionnaire studies are concluded to be relatively cheap and reliable, and a compilation of validated questions is described. Such questions could be tailored to individual practice needs and used in the early detection of asthma, giving the potential for early intervention and improved quality of life.

Screening for childhood asthma using an exercise test

BACKGROUND

Screening for asthma in children in the community could have advantages at a time when prevalence rates of the condition and associated hospital admission rates are rising.

AIM

The aim of this study was to assess the usefulness of a standard exercise test as a marker of asthma or potential asthma in children, and to examine the relationship between asthma and other respiratory tract illnesses.

METHOD

In 1985 a cross-sectional research study was undertaken in 10 primary schools in West Glamorgan; the children were followed up over six years until 1991. The exercise test involved measuring peak expiratory flow rate before and after the children ran as fast as they could for six minutes. A control group of children with a negative exercise test result were compared with those not known to have asthma who had a positive result (fall in peak expiratory flow rate of 15% or greater), using clinical data. Similar clinical comparisons were undertaken between the children known to have asthma and a control group.

RESULTS

Of 864 children not known to have asthma, 60 had a positive exercise result. Of 92 children known to have asthma, 33 had a positive test result and seven were unable to finish the test because of bronchospasm, a sensitivity of 43% and a specificity of 93%. Follow up of 55 of the 60 children not known to have asthma but who had an abnormal response to the test showed that 32 had developed clinically recognizable asthma six years later. There was a significantly higher prevalence of atopic and respiratory illnesses (otitis media, hay fever and eczema) in the group of children with bronchial hyperreactivity demonstrated on exercise than in those without bronchial hyperreactivity.

CONCLUSION

This research shows that bronchial hyperreactivity demonstrated by an exercise test can be a marker for childhood asthma. The study has also identified other respiratory tract illnesses which appear to belong to the same spectrum as asthma.

Uses and limitations of mortality and health care utilization statistics in asthma research

Mortality and health care utilization (HCU) statistics for asthma reflect both the acute and chronic aspects of this condition. We present a conceptual model that incorporates this dichotomy and also distinguishes between measures of disease occurrence (e.g., incidence and prevalence) and measures of disease management. We also discuss the use of mortality and HCU statistics in the literature, review their limitations and advantages, and make a number of general recommendations for their use.