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

Breathing exercises for adults with asthma

BACKGROUND

Breathing exercises have been widely used worldwide as a non-pharmacological therapy to treat people with asthma. Breathing exercises aim to control the symptoms of asthma and can be performed as the Papworth Method, the Buteyko breathing technique, yogic breathing, deep diaphragmatic breathing or any other similar intervention that manipulates the breathing pattern. The training of breathing usually focuses on tidal and minute volume and encourages relaxation, exercise at home, the modification of breathing pattern, nasal breathing, holding of breath, lower rib cage and abdominal breathing.

OBJECTIVES

To evaluate the evidence for the efficacy of breathing exercises in the management of people with asthma.

SEARCH METHODS

To identify relevant studies we searched The Cochrane Library, MEDLINE, Embase, PsycINFO, CINAHL and AMED and performed handsearching of respiratory journals and meeting abstracts. We also consulted trials registers and reference lists of included articles. The most recent literature search was on 4 April 2019.

SELECTION CRITERIA

We included randomised controlled trials of breathing exercises in adults with asthma compared with a control group receiving asthma education or, alternatively, with no active control group.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data. We used Review Manager 5 software for data analysis based on the random-effects model. We expressed continuous outcomes as mean differences (MDs) with confidence intervals (CIs) of 95%. We assessed heterogeneity by inspecting the forest plots. We applied the Chi2 test, with a P value of 0.10 indicating statistical significance, and the I2 statistic, with a value greater than 50% representing a substantial level of heterogeneity. The primary outcome was quality of life.

MAIN RESULTS

We included nine new studies (1910 participants) in this update, resulting in a total of 22 studies involving 2880 participants in the review. Fourteen studies used Yoga as the intervention, four studies involved breathing retraining, one the Buteyko method, one the Buteyko method and pranayama, one the Papworth method and one deep diaphragmatic breathing. The studies were different from one another in terms of type of breathing exercise performed, number of participants enrolled, number of sessions completed, period of follow-up, outcomes reported and statistical presentation of data. Asthma severity in participants from the included studies ranged from mild to moderate, and the samples consisted solely of outpatients. Twenty studies compared breathing exercise with inactive control, and two with asthma education control groups. Meta-analysis was possible for the primary outcome quality of life and the secondary outcomes asthma symptoms, hyperventilation symptoms, and some lung function variables. Assessment of risk of bias was impaired by incomplete reporting of methodological aspects of most of the included studies. We did not include adverse effects as an outcome in the review. Breathing exercises versus inactive control For quality of life, measured by the Asthma Quality of Life Questionnaire (AQLQ), meta-analysis showed improvement favouring the breathing exercises group at three months (MD 0.42, 95% CI 0.17 to 0.68; 4 studies, 974 participants; moderate-certainty evidence), and at six months the OR was 1.34 for the proportion of people with at least 0.5 unit improvement in AQLQ, (95% CI 0.97 to 1.86; 1 study, 655 participants). For asthma symptoms, measured by the Asthma Control Questionnaire (ACQ), meta-analysis at up to three months was inconclusive, MD of -0.15 units (95% CI -2.32 to 2.02; 1 study, 115 participants; low-certainty evidence), and was similar over six months (MD -0.08 units, 95% CI -0.22 to 0.07; 1 study, 449 participants). For hyperventilation symptoms, measured by the Nijmegen Questionnaire (from four to six months), meta-analysis showed less symptoms with breathing exercises (MD -3.22, 95% CI -6.31 to -0.13; 2 studies, 118 participants; moderate-certainty evidence), but this was not shown at six months (MD 0.63, 95% CI -0.90 to 2.17; 2 studies, 521 participants). Meta-analyses for forced expiratory volume in 1 second (FEV1) measured at up to three months was inconclusive, MD -0.10 L, (95% CI -0.32 to 0.12; 4 studies, 252 participants; very low-certainty evidence). However, for FEV1 % of predicted, an improvement was observed in favour of the breathing exercise group (MD 6.88%, 95% CI 5.03 to 8.73; five studies, 618 participants). Breathing exercises versus asthma education For quality of life, one study measuring AQLQ was inconclusive up to three months (MD 0.04, 95% CI -0.26 to 0.34; 1 study, 183 participants). When assessed from four to six months, the results favoured breathing exercises (MD 0.38, 95% CI 0.08 to 0.68; 1 study, 183 participants). Hyperventilation symptoms measured by the Nijmegen Questionnaire were inconclusive up to three months (MD -1.24, 95% CI -3.23 to 0.75; 1 study, 183 participants), but favoured breathing exercises from four to six months (MD -3.16, 95% CI -5.35 to -0.97; 1 study, 183 participants).

AUTHORS' CONCLUSIONS

Breathing exercises may have some positive effects on quality of life, hyperventilation symptoms, and lung function. Due to some methodological differences among included studies and studies with poor methodology, the quality of evidence for the measured outcomes ranged from moderate to very low certainty according to GRADE criteria. In addition, further studies including full descriptions of treatment methods and outcome measurements are required.

Special considerations--asthma in children

BACKGROUND

Asthma is among the most common chronic diseases of childhood. Management of pediatric asthma requires an understanding of the issues that uniquely effect children. This review provides the reader with the current state and future directions of pediatric asthma.

METHODS

Review of the pediatric asthma literature was undertaken with emphasis on randomized controlled trials and systematic reviews.

RESULTS

The prevalence of pediatric asthma remains elevated and is increasingly being appreciated in select global regions. Effective treatment in any setting begins with a focused medical history that queries key asthma features that inform both diagnostic and monitoring strategies. A thorough medical history may yield comorbid upper airway disorders and allergic triggers that could potentially exacerbate airway inflammation. Pre-bronchodilator and post-bronchodilator lung function testing is a preferable diagnostic strategy to quantitatively assess obstructive pulmonary disease among children capable of performing the testing maneuvers. Pediatric asthmatics who continue to have poor disease control require monitoring of medication adherence and drug delivery techniques, because both are often linked with disease outcomes. Therapeutic strategies in children are notably distinct from adults due to the possible effects of inhaled corticosteroids on reduced bone mineral density and growth. Adolescents may also require more time to address the psychosocial complexities that may complicate the required daily usage of asthma medicines.

CONCLUSION

Asthmatic children are distinct from their adult counterparts due to limitations inherent in the pediatric age group. A unified and evidence-based approach to pediatric asthma may improve clinical outcomes.

Breathing exercises for adults with asthma

BACKGROUND

Breathing exercises have been widely used worldwide as a complementary therapy to the pharmacological treatment of people with asthma.

OBJECTIVES

To evaluate the evidence for the efficacy of breathing exercises in the management of patients with asthma.

SEARCH METHODS

The search for trials led review authors to review the literature available in The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and AMED and to perform handsearching of respiratory journals and meeting abstracts. Trial registers and reference lists of included articles were also consulted.The literature search has been updated to January 2013.

SELECTION CRITERIA

We included randomised controlled trials of breathing exercises in adults with asthma compared with a control group receiving asthma education or, alternatively, with no active control group.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. RevMan software was used for data analysis based on the fixed-effect model. Continuous outcomes were expressed as mean differences (MDs) with confidence intervals (CIs) of 95%. Heterogeneity was assessed by inspecting the forest plots. The Chi(2) test was applied, with a P value of 0.10 indicating statistical significance. The I(2) statistic was implemented, with a value greater than 50% representing a substantial level of heterogeneity.

MAIN RESULTS

A total of 13 studies involving 906 participants are included in the review. The trials were different from one another in terms of type of breathing exercise performed, number of participants enrolled, number and duration of sessions completed, outcomes reported and statistical presentation of data. Asthma severity in participants from the included studies ranged from mild to moderate, and the samples consisted solely of outpatients. The following outcomes were measured: quality of life, asthma symptoms, number of acute exacerbations and lung function. Eleven studies compared breathing exercise with inactive control, and two with asthma education control groups. All eight studies that assessed quality of life reported an improvement in this outcome. An improvement in the number of acute exacerbations was observed by the only study that assessed this outcome. Six of seven included studies showed significant differences favouring breathing exercises for asthma symptoms. Effects on lung function were more variable, with no difference reported in five of the eleven studies that assessed this outcome, while the other six showed a significant difference for this outcome, which favoured breathing exercises. As a result of substantial heterogeneity among the studies, meta-analysis was possible only for asthma symptoms and changes in the Asthma Quality of Life Questionnaire (AQLQ). Each meta-analysis included only two studies and showed a significant difference favouring breathing exercises (MD -3.22, 95% CI -6.31 to -0.13 for asthma symptoms; MD 0.79, 95% CI 0.50 to 1.08 for change in AQLQ). Assessment of risk of bias was impaired by incomplete reporting of methodological aspects of most of the included trials.

AUTHORS' CONCLUSIONS

Even though individual trials reported positive effects of breathing exercises, no reliable conclusions could be drawn concerning the use of breathing exercises for asthma in clinical practice. This was a result of methodological differences among the included studies and poor reporting of methodological aspects in most of the included studies. However, trends for improvement are encouraging, and further studies including full descriptions of treatment methods and outcome measurements are required.

Oscillometric and spirometric bronchodilator response in preschool children with and without asthma

BACKGROUND

Bronchodilator responses (BDR) are routinely used in the diagnosis and management of asthma; however, their acceptability and repeatability have not been evaluated using quality control criteria for preschool children.

OBJECTIVES

To compare conventional spirometry with an impulse oscillometry system (IOS) in healthy and asthmatic preschool children.

METHODS

Data from 30 asthmatic children and 29 controls (two to six years of age) who underwent IOS and spirometry before and after salbutamol administration were analyzed.

RESULTS

Stable asthmatic subjects significantly differed versus controls in their spirometry-assessed BDR (forced expiratory volume in 1 s [FEV1], forced vital capacity and forced expiratory flow at 25% to 75% of forced vital capacity) as well as their IOS-assessed BDR (respiratory resistance at 5 Hz [Rrs5], respiratory reactance at 5 Hz and area under the reactance curve). However, comparisons based on the area under the ROC curve for ΔFEV1 %initial versus ΔRrs5 % initial were 0.82 (95% CI 0.71 to 0.93) and 0.75 (95% CI 0.62 to 0.87), respectively. Moreover, the sensitivity and specificity for ΔFEV1 >=9% were 0.53 and 0.93, respectively. Importantly, sensitivity increased to 0.63 when either ΔFEV1 >=9% or ΔRrs5 >=29% was considered as an additional criterion for the diagnosis of asthma.

CONCLUSION

The accuracy of asthma diagnosis in preschool children may be increased by combining spirometry with IOS when measuring BDR.

Predictors for asthma at age 7 years for low-income children enrolled in the Childhood Asthma Prevention Study

OBJECTIVE

To identify the predictive factors of early childhood wheezing in children of low socioeconomic status.

STUDY DESIGN

The Childhood Asthma Prevention Study enrolled 177 low-income children (9-24 months old) with frequent wheezing. At age 7 years, presence of asthma was assessed through caregiver reports of physician diagnosis of asthma (CRPDA) and corroborated by assessment of bronchial hyperresponsiveness (BHR). Lung function, inflammatory markers, and asthma symptom severity were compared for children with ±CRPDA, ±BHR, and asthma. Baseline predictors for CRPDA, BHR, and asthma at 7 years of age were examined.

RESULTS

Maternal symptom report strongly differentiated children with +CRPDA (49%) despite comparable airflow measurements (P < .0001), and spirometric lung function measurements were different for +BHR (65%) versus -BHR (P < .005). Univariate analyses revealed different baseline predictors of +CRPDA and +BHR for children at age 7 years. Higher levels of maternal psychological resources were associated with +CRPDA, but not +BHR. Only 39% of children with a history of frequent wheezing met the conservative definition of asthma at age 7 years, with the following significant predictors found: low birth weight, baseline symptom severity, and maternal psychological resources.

CONCLUSIONS

This low-income, multi-ethnic group of wheezing infants represents a unique population of children with distinct characteristics and risks for persistent asthma. Determination of asthma status at 7 years of age required objective measurement of BHR in addition to CRPDA. The association of maternal psychological resources with +CRPDA may represent a previously unrecognized factor in the determination of asthma status among low-income groups.

Genetics of asthma: a molecular biologist perspective

Asthma belongs to the category of classical allergic diseases which generally arise due to IgE mediated hypersensitivity to environmental triggers. Since its prevalence is very high in developed or urbanized societies it is also referred to as "disease of civilizations". Due to its increased prevalence among related individuals, it was understood quite long back that it is a genetic disorder. Well designed epidemiological studies reinforced these views. The advent of modern biological technology saw further refinements in our understanding of genetics of asthma and led to the realization that asthma is not a disorder with simple Mendelian mode of inheritance but a multifactorial disorder of the airways brought about by complex interaction between genetic and environmental factors. Current asthma research has witnessed evidences that are compelling researchers to redefine asthma altogether. Although no consensus exists among workers regarding its definition, it seems obvious that several pathologies, all affecting the airways, have been clubbed into one common category called asthma. Needless to say, genetic studies have led from the front in bringing about these transformations. Genomics, molecular biology, immunology and other interrelated disciplines have unearthed data that has changed the way we think about asthma now. In this review, we center our discussions on genetic basis of asthma; the molecular mechanisms involved in its pathogenesis. Taking cue from the existing data we would briefly ponder over the future directions that should improve our understanding of asthma pathogenesis.

Validating an asthma case detection instrument in a Head Start sample

Although specific tests screen children in preschool programs for vision, hearing, and dental conditions, there are no published validated instruments to detect preschool-age children with asthma, one of the most common pediatric chronic conditions affecting children in economically disadvantaged communities of color. As part of an asthma education intervention, a 15-item Brief Respiratory Questionnaire (BRQ) was developed to detect children with probable asthma in Head Start and subsidized preschool settings in communities with high asthma prevalence and associated morbidity. Preschool personnel administered the BRQ to consenting parents of 419 enrolled children. Trained interviewers administered validation interviews (VALs) to parents of 149 case-positive children and 51 case-negative children. Three physicians independently assessed deidentified summaries of the VALs that captured responses about signs and symptoms of asthma, diagnosis and treatment, and use of medical services. The physicians' assessments of the summarized VALs were the validated standard to which the BRQ classifications were compared. A simple algorithm of 4 items was identified that can be administered and scored by nonmedical preschool personnel in less than 5 minutes. The chance-corrected agreement between these 4 items of the BRQ and the VAL was good: kappa, .73 (95% confidence interval, 0.62-0.84); specificity, 96%; sensitivity, 73%; and positive predictive value, 97%. The BRQ appears to be a valid instrument for detecting children with probable asthma in Head Start and other subsidized preschool settings in communities with high prevalence of asthma.

[Current prevalence of asthma in schoolchildren in San Sebastián (Spain)]

OBJECTIVE

To determine the current prevalence of asthma in children aged 6-12 years old in San Sebastian (Guipuzcoa, Spain).

PATIENTS AND METHODS

An observational, cross sectional study was performed in 6-12-year-old children in schools. The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was employed. Bronchial hyperresponsiveness was investigated using the free running test, with peak expiratory flow (PEF) measured with a peak flow meter as the main measurement. The ISAAC questionnaire (n = 919) was distributed to 460 boys (50.1%) and 459 girls (49.9%) with a mean age of 8 years (SD 1.87). The response rate to the questionnaire was 93 % (n = 855). Participation in the free running test was 90.8% (n = 835). A total of 89.88% of the children (n = 826) completed both tests.

RESULTS

The questionnaire of symptoms and signs compatible with asthma revealed a current prevalence of asthma of 25.56% (n = 216) and a cumulative prevalence of 25.44% (n = 85). Nocturnal asthma was found in 29.37% (n = 47) and severe asthma in 9.27% (n = 14). Bronchial hyperresponsiveness was found in 23% of the participants. An epidemiological diagnosis of asthma (asthma-related symptoms plus bronchial hyperresponsiveness) was made in 6.54%.

CONCLUSIONS

The current prevalence of asthma in 6-12-year-old schoolchildren in San Sebastian, determined through symptoms and signs compatible with asthma in the previous year and a positive free running test, is similar to that reported in other national studies.

Prevalence of asthma and asthma-like symptoms in inner-city schoolchildren

This study investigates the prevalence of asthma and asthma-related symptoms in New Orleans inner-city schoolchildren. A cross-sectional survey of 1535 elementary, middle, and high school children (aged 5-18) was conducted by using the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire. Lifetime prevalence of wheezing was 39.4%, and lifetime prevalence of asthma was 24.4%. Wheezing during the previous 12 months was reported by 25.7% of the sample. Twenty-one percent of respondents reported having one or more attacks of wheezing per year, with 5.6% reporting four or more attacks per year. Many participants reported sleep disturbance (15.4%), with 6.2% reporting sleep disturbance more than once a week. The 12-month rate of speech limitation due to asthma exacerbation was 6.6%. Exercise-induced asthma was reported by 16.9% of the students, and nocturnal cough (not associated with cold) was reported by 27.3%. Overall, boys reported higher rates of symptoms than girls, and younger children (aged 6-7) reported greater symptoms than older children (aged 13-14). These findings show that prevalence of asthma in this population is elevated, and the ISAAC written questionnaire successfully identified inner-city children at risk for asthma in New Orleans.

Effect of asthma intervention on children with undiagnosed asthma

OBJECTIVE

To measure the effect of an asthma intervention on the functional status and morbidity of children with undiagnosed asthma.

STUDY DESIGN

Data from a randomized trial were used to compare outcomes at baseline and follow-up for children with undiagnosed and diagnosed asthma. We studied 510 symptomatic children with diagnosed asthma (diagnosed) and 299 children with symptoms but no diagnosis (undiagnosed). Baseline functioning and morbidity were similar for undiagnosed and diagnosed patients classified as moderate-severe.

RESULTS

There were fewer undiagnosed reported allergies, seasonal symptoms, and other respiratory diagnoses (all P < 0.01). Among the moderate-severe, functional status, for example, symptom-days ( P = .02), symptom-nights ( P < .01), and days of restricted activity ( P < .01), was significantly reduced at follow-up for the undiagnosed in the intervention group but not for undiagnosed control subjects. Findings were similar for children with diagnosed asthma.

CONCLUSIONS

Children with undiagnosed asthma were generally nonatopic, although some had symptoms at a level comparable to children with a diagnosis. The intervention successfully improved functional status for children with undiagnosed asthma as well as for children with diagnosed asthma. These results can be applied to ongoing discussions related to case detection.

Identification of gaps in the diagnosis and treatment of childhood asthma using a community-based participatory research approach

The goal of this investigation was to use a community-based participatory research approach to develop, pilot test, and administer an asthma screening questionnaire to identify children with asthma and asthma symptoms in a community setting. This study was conducted as the recruitment effort for Community Action Against Asthma, a randomized trial of a household intervention to reduce exposure to environmental triggers of asthma and was not designed as a classic prevalence study. An asthma screening questionnaire was mailed and/or hand delivered to parents of 9,627 children, aged 5 to 11 years, in two geographic areas of Detroit, Michigan, with predominantly African American and Hispanic populations. Additional questionnaires were distributed via community networking. Measurements included parent report of their child's frequency of respiratory symptoms, presence of physician diagnosis of asthma, and frequency of doctor-prescribed asthma medication usage. Among the 3,067 completed questionnaires, 1,570 (51.2% of returned surveys, 16.3% of eligible population) were consistent with asthma of any severity and 398 (12.9% of returned surveys, 4.1% of eligible population) met criteria for moderate-to-severe asthma. Among those meeting criteria for moderate-to-severe asthma, over 30% had not been diagnosed by a physician, over one half were not taking daily asthma medication, and one quarter had not taken any physician-prescribed asthma medication in the past year. Screening surveys conducted within the context of a community-based participatory research partnership can identify large numbers of children with undiagnosed and/or undertreated moderate-to-severe asthma. These children are likely to benefit from interventions to reduce morbidity and improve quality of life.

Breathing exercises for asthma

BACKGROUND

There is much anecdotal evidence in Eastern and Western literature describing considerable benefits for patients with asthma when treated with breathing interventions. The term 'breathing exercise, training and retraining' has numerous interpretations depending on the nature of the therapy, therapist and cultural background.

OBJECTIVES

To assess the evidence for the efficacy of breathing retraining in the treatment of patients with asthma.

SEARCH STRATEGY

Trials were searched for in the Cochrane Airways Group trials register, Cochrane Complementary Medicine Field trials register, EMBASE: Physical Medicine & Rehabilitation Field, and Databases of the physiotherapy library of current research, World Congress of Physical Therapy Proceedings (1995) and AMED (Allied & Complementary Medicine Database 1985-2003/4). Hand searching of the Association of Chartered Physiotherapists in Respiratory Care Journals was undertaken. Chartered physiotherapists in the field of respiratory medicine were contacted and appeals made in the 'Physiotherapy' Journal and the Physiotherapy Respiratory Care magazine. Searches were undertaken of bibliographies from the included studies and other appropriate papers. Authors of included studies were contacted for information concerning other relevant trials.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of breathing retraining in patients of all ages with a diagnosis of asthma. Breathing retraining should be a major component of the treatment intervention.

DATA COLLECTION AND ANALYSIS

Two reviewers (EH & FR) independently assessed trial quality and extracted data. Authors of included trials were contacted for additional data. Where possible adverse effects were noted.

MAIN RESULTS

Abstracts were identified and 42 full text papers were obtained for assessment and possible inclusion. Thirty five studies were excluded. A total of five studies were included in the original review. Two further studies have been added to this update. Most studies were of small size. Two studies demonstrated significant reductions in rescue bronchodilator use and three studies showed reductions in acute exacerbations, although these were measured in different ways. Two single studies showed significant improvements in quality of life measures. Overall, benefits of breathing exercises were found in isolated outcome measures in single studies. Five studies compared breathing retraining with no active control and two with asthma education control groups.

REVIEWER'S CONCLUSIONS

Comparisons and conclusions were difficult to evaluate as treatment interventions and outcome measurements from the seven trials varied considerably. At present therefore no reliable conclusions can be drawn concerning the use of breathing exercises for asthma in clinical practice. However trends for improvement, notably in quality of life measurements, are encouraging and further studies including full descriptions of treatment methods and outcome measurements are required.

The relationship of health insurance to the diagnosis and management of asthma and respiratory problems in children in a predominantly Hispanic urban community

OBJECTIVES

As part of an asthma screening study, we evaluated the relationship of health care insurance coverage to the diagnosis and treatment of elementary school children for asthma and related respiratory problems from 1998 through 2001.

METHODS

A bilingual questionnaire assessing health care coverage, asthma diagnosis, respiratory symptoms, and use of medications was distributed to parents of 6235 public and private school children in grades 2 through 5 in Passaic, NJ.

RESULTS

Responses for 4380 children (70%) revealed disparities in health care coverage and asthma diagnosis among racial and ethnic groups. Mexican and Dominican children had significant increases in health care coverage over the 4 years.

CONCLUSIONS

The percentage of children with health insurance grew from 67% in 1998 to 81% in 2001, and the increase was related to NJ KidCare. Diagnosis of asthma and treatment were related to health care coverage.

Impulse oscillometry provides an effective measure of lung dysfunction in 4-year-old children at risk for persistent asthma

BACKGROUND

Objective lung function measurements are routinely used to diagnose and manage asthma, but their utility for young children has not been defined.

OBJECTIVE

Bronchodilator responses were measured by means of impulse oscillometry (IOS) and compared with conventional spirometry to determine the value of lung function measures in 4-year-old asthma-prone children.

METHODS

The study participants were in the Childhood Asthma Prevention Study (National Institute of Health/National Institute of Allergy and Infectious Diseases) and at risk for asthma. At age 4 years, concurrent asthma was determined by using a previously validated modified American Thoracic Society questionnaire. Children performed IOS and spirometry before and after albuterol administration and underwent skin prick testing to 13 common allergens to assess atopy. IOS measures were as follows: airways resistance at 5 Hz and 10 Hz, airways reactance at 5 Hz and 10 Hz, and resonant frequency.

RESULTS

Asthmatic patients versus nonasthmatic patients significantly differed in their IOS-assessed bronchodilator responses through Delta resistance at 5 Hz (medians, 27% vs 17%; P =.02) and Delta resistance at 10 Hz (24% vs 16%; P =.03). Because atopic children who have frequent wheezing are at risk for persistent asthma, the data were analyzed in regard to atopic patients with or without asthma. IOS strongly distinguished atopic asthmatic children through Delta resistance at 5 Hz (36% vs 13%, P =.007), Delta resistance at 10 Hz (25% vs 11%, P =.02), and Delta reactance at 10 Hz (47% vs 12%, P =.03). Conventional spirometry did not establish similar statistically significant findings.

CONCLUSION

IOS bronchodilator responses are remarkably abnormal in 4-year-old children, who are most likely to have persistent asthma. IOS is a useful diagnostic tool in early asthma development and might be a helpful objective outcome measure of early interventions.

Population-based screening or case detection for asthma: are we ready?

Asthma is a prevalent health problem for which there are effective treatments. By identifying people with asthma and treating them effectively, the burden of asthma in the United States should be reduced. Detecting people with asthma through screening programs seems a logical approach to the problem. This article assesses our readiness for population-based screening and case detection programs for asthma and examines these activities in relation to World Health Organization criteria for determining the appropriateness of screening programs. Given that, at this time, a number of the criteria have not been met, we conclude that population-based approaches to screening and case detection of asthma are of unproven benefit and need further research. A more appropriate focus may be to ensure that all people who are diagnosed with asthma receive appropriate medical care.

Outcome results of a school-based screening program for undertreated asthma

BACKGROUND

Undertreatment of asthma is associated with significant potentially preventable morbidity, including frequent school absences. Guideline dissemination and clinician education have met with variable success. School-based identification of children with potentially undertreated asthma may provide an alternative strategy for improving asthma management in children.

OBJECTIVE

To evaluate the effectiveness of school-based identification of potentially undertreated asthma.

METHODS

A controlled trial of school-based identification of children with known but symptomatic asthma using mailed parent surveys, letters recommending medical follow-up, and medical record review to evaluate changes in asthma treatment after referral.

RESULTS

Most parents (79.9%, n = 5,116 respondents) responded to the survey and 19.4% (n = 994) of children were reported to have a physician diagnosis of asthma or reactive airway disease. Letters of referral were sent to 489 children with parent-reported asthma who were identified as having potentially undertreated asthma. Approximately one-third (31.2%, n = 153) of these children had physician visits, and 92 (18.8% of all referred) had documented medication changes. In addition, there were 20 new physician diagnoses in this group of children. In the control group of 604 children with asthma, there were significantly fewer children with asthma-related visits (131, 21.7%, P = 0.0004) and children with medication changes (74, 12.3%, P = 0.002) in a comparable 6-month window.

CONCLUSIONS

School-based screening or case identification increased the number of physician asthma-related visits and changes in asthma therapy.

Household exposure factors, asthma, and school absenteeism in a predominantly Hispanic community

The Passaic Asthma Reduction Effort (PARE) used an asthma symptom and household exposure factor questionnaire to screen 4634 elementary school children over a 4-year period in Passaic, New Jersey. During the first year, an additional 240 preschool children were also screened. Overall, 16% of the school children were reported by their parents to have been diagnosed with asthma. In all, 30% of responding families claimed to have at least one family member diagnosed with asthma and this was five times more likely if the target child had asthma. Exposures consistently associated with childhood asthma diagnosis included environmental tobacco smoke (ETS), presence of dampness/mold, roaches, and furry pets in the home. Diagnosis of asthma was primarily associated with all six symptoms used in the PARE questionnaire, and secondarily with environmental factors. Puerto Rican and black children had the highest asthma prevalence (26% and 33%), while Mexican children had the lowest (7%). Use of medications and school absenteeism among asthmatic children were associated with wheeze and night cough, but not with any specific environmental exposure. Increased school absenteeism by children undiagnosed with asthma was associated with ETS and dampness/mold in the home. Differences in asthma diagnosis and absenteeism in response to environmental factors were found across ethnic subgroups. Getting asthmatic children on medical management protocols and providing families with education about environmental risk reduction should aid in reducing morbidity in this ethnically complex population. Such coordinated efforts offer the promise of reducing school absenteeism.

Issues in identifying asthma and estimating prevalence in an urban school population

This article first presents salient issues related to identifying children in urban schools who might benefit from asthma services. It discusses a brief questionnaire for identifying cases and problems in estimating asthma prevalence. Subsequently, results of case detection in 14 urban schools are presented and discussed in light of these issues. The questionnaire was employed with parents of 4,653 African-American children in Detroit. Results suggest that determining number, type, and frequency of symptoms may be necessary to ascertain prevalence of asthma. Using only number and type produced a rate of asthma of 25%. Adding frequency provided a more conservative estimate of 19%. About 9% of children exhibiting symptoms of asthma had no physician diagnosis. Only 25% with symptoms reflecting mild persistent, 35% with moderate persistent, and 26% with severe persistent disease had prescriptions for anti-inflammatory medicine. Further, 23% of children with asthma-like symptoms had no prescription for asthma medicine of any type.

CONCLUSIONS

(1) low-cost procedures can be used in schools to identify children with suspected undiagnosed and undertreated asthma; (2) prevalence estimates for asthma in the group of urban school children studied are among the highest in the United States; and (3) asthma is undertreated in this sample.

Parents' accounts of wheeze and asthma related symptoms: a qualitative study

AIMS

To examine parents' accounts of how they recognise and judge respiratory symptoms in children, and to investigate their interpretations of respiratory survey questions about wheeze, shortness of breath, and cough.

METHODS

Qualitative study using semistructured interviews. Data were analysed using the constant comparative method. Nineteen parents of children aged under 6 years were recruited from a cohort of parents who had responded to an earlier respiratory symptom survey and from one general practice.

RESULTS

Parents judged respiratory symptoms using a range of cues, including changes in the sound of breathing and changes in appearance and behaviour. Experiential resources and contextual factors played an important role in parents' judgements. Interpretations of questions about respiratory symptoms were varied, particularly in relation to the terms "attacks of wheeze" and "shortness of breath". Parents' descriptions of wheeze differed from descriptions of the sound of wheeze used in some survey questionnaires. Parents drew fine distinctions between different "types" of cough and identified a distinct "asthma" cough.

CONCLUSIONS

Attention needs to be given to the complexity of reporting respiratory symptoms in children and to the importance of contextual factors in parents' judgements. We suggest that questions which require parents to report on children's internal feelings or states be avoided. Consideration should be given to providing parents with explicit direction on what cues to attend to or ignore in reporting symptoms, and to clarifying some questions that are currently used in clinical practice and in surveys.