Asthma In Schoolchildren Research Articles

Risk factors and prevalence of asthma in schoolchildren in Castellon (Spain): a cross-sectional study

BackgroundResearch on potential risk factors of asthma can enhance our understanding of geographic differences and inform decisions on preventive strategies. MethodsIn 2002, a cross-sectional population-based study was carried out in the area of Castellon (Spain), following the International Study of Asthma and Allergies in Childhood (ISAAC) Phase III methodology. Asthma symptoms and related risk factor questionnaires were completed by parents of 6-7 year-old schoolchildren. Logistic regression was used in the analysis. ResultsParticipation rate was 88 % (4492 of 4872 schoolchildren). Prevalence of wheeze in the past year, asthma ever, and physician-diagnosed asthma were 8 %, 7 % and 6 %, respectively. Risk factors independently associated with all three asthma case definitions were history of bronchitis or pneumonia, allergic rhinitis, family members with atopic disease, and residing in an industrialised area. Risk factors for asthma ever and physician-diagnosed asthma were male sex, atopic eczema and presence of a dog at home; exclusive breast-feeding and the presence of another animal (not a dog or cat) were protective factors. Maternal age was inversely related to physician-diagnosed asthma. Residence in an area of heavy truck traffic and the father smoking at home were associated with asthma ever. Risk factors for wheeze in the past year were low social class, history of sinusitis and the father smoking at home. ConclusionsEnvironmental factors are related to the presence of asthma. Preventive measures should be directed to improving air pollution, promoting breast-feeding and reducing smoking in the home.

The Use of Exhaled Nitric Oxide in the Diagnosis of Asthma in School Children

To evaluate the yield of the fractional exhaled nitric oxide (FeNO) in the diagnosis of asthma compared with spirometry and induced sputum cytologic study in school-age children. Consecutive children referred for evaluation of possible asthma were included. At referral, all children completed FeNO measurement, sputum induction for eosinophil count (eos%) and spirometry. The diagnosis of asthma was performed after 18 months with conventional criteria. Receiver operating curves were used to determine cutoff points for disease status, and accuracy was calculated. A total of 150 children were included: 69 with steroid-naïve asthma, 44 without asthma, and 37 with asthma treated with controllers. FeNO and eos% levels were significantly higher in those with steroid-naïve asthma (P < .0001). The area under the receiver operating curve for FeNO and eos% were very high compared with forced expiratory volume in 1 second (0.906, 0.921, 0.606, respectively). The sensitivity, specificity, and positive and negative predictive values for best cutoff points of FeNO (19 parts per billion) were 80%, 92%, 89%, and 86%, respectively, and were similar to eos% (best cutoff = 2.7%): 81%, 92%, 89%, 85%, respectively. FeNO measurement is useful in early diagnosis of pediatric asthma. We suggest considering FeNO measurement in the evaluation of children suspected of having asthma, especially in cases where the diagnosis is not clear.

Percent body fat, skinfold thickness or body mass index for defining obesity or overweight, as a risk factor for asthma in schoolchildren: which one to use in epidemiological studies?

None of the epidemiological studies indicating that obesity is a risk factor for asthma in schoolchildren have used the percent body fat (PBF) to define obesity. The present study compares the definition of obesity using body mass index (BMI), PBF and the raw sum of the thickness of four skinfolds (SFT) to evaluate this condition as a risk factor for asthma. All classes of children of the target ages of 6-8 years of all schools in four municipalities of Murcia (Spain) were surveyed. Participation rate was 70.2% and the number of children included in the study was 931. Height, weight and SFT (biceps, triceps, subscapular and suprailiac) were measured according to standard procedures. Current active asthma was defined from several questions of the International Study of Asthma and Allergies in Childhood questionnaire. Obesity was defined using two standard cut-off points for BMI and PBF, and the 85th percentile for BMI, PBF and SFT. The highest quartile of each type of measurement was also compared with the lowest. A multiple logistic regression analysis was made for the various obesity definitions, adjusting for age, asthma in the mother and father and gender. The adjusted odds ratios of having asthma among obese children were different for boys and girls and varied across the different obesity definitions. For the standard cut-off points of BMI they were 1.19 [95% confidence interval (CI) 0.41-3.43] for girls and 2.00 (95% CI 0.97-4.10) for boys; however, for PBF (boys 25%, girls 30%) the corresponding figures were 1.54 (95% CI 0.63-3.73) and 1.20 (95% CI 0.66-2.21). BMI, PBF and SFT showed more consistency between each other when using the other cut-off points. BMI, PBF (except standard cut-off points) and SFT produce relatively comparable results when analysing the interaction between obesity and asthma.

Lung function and bronchial responsiveness after Mycoplasma pneumoniae infection in early childhood

Mycoplasma (M.) pneumoniae has been associated with exacerbation of symptoms in asthmatic school children and adults; and an etiological role in asthma has been suggested. The purpose of this study was to investigate whether infection with M. pneumoniae in early childhood has a long-term influence on lung function and bronchial responsiveness. In a retrospective, clinical cohort-study children younger than 5 years-of-age when PCR-tested for M. pneumoniae were enrolled. Sixty-five children with clinical symptoms suggesting infection with M. pneumoniae during an epidemic season completed a clinical follow-up examination including lung function testing (28 PCR-positive and 37 PCR-negative). In addition to the PCR-test for M. pneumoniae all respiratory tract specimens were additionally tested for other atypical bacteria and for viruses by PCR. Lung function was measured as specific airway resistance by whole-body plethysmography and bronchial hyperresponsiveness was assessed by cold, dry air hyperventilation. Neither baseline lung function nor bronchial response to cold dry air hyperventilation differed between M. pneumoniae-positive and -negative children: mean baseline lung function were 1.17 versus 1.21 (kPa sec), P = 0.45; and mean change in specific resistance was 13% versus 9%, P = 0.42. In conclusion, M. pneumoniae infection in early childhood was not associated with long-term effects on lung function and bronchial hyperresponsiveness 2 years after infection.

Risk Factors of Childhood Asthma in Sao Jose do Rio Preto, Sao Paulo, Brazil

Epidemiological studies have shown increased prevalence of asthma over the last decades and a considerable variation in these rates between different countries, mainly developed. Changes in lifestyle of different populations could explain the increasing prevalence of asthma and its different rates in different communities. A case-control study was conducted to investigate some risks factors associated to asthma in schoolchildren in São José do Rio Preto, São Paulo, Brazil. A total of 3793 self-administered written questionnaire (WQ) was filled in by parents of 6-7-year-old schoolchildren, applying the International Study of Asthma and Allergies in Childhood (ISAAC) protocol. Additionally, was added a supplementary WQ evaluating risk factors: gender, personal history of rhinitis and atopic eczema, familial history of atopy, older siblings, day care, breastfeeding, and exposure to pets and to cigarette smoking. Children whose parents responded affirmatively to question 'Has your child had wheezing in the past 12 monthsquest;' were identified as having current asthma. The prevalence of current asthma was 18.3%. In multivariate analysis the following risk factors were associated with asthma: rhinitis (OR = 10.6; 95% CI = 8.27-13.56), atopic eczema (OR = 1.54; 95% CI = 1.00-2.35), father with asthma (OR = 3.49; 95% CI = 1.83-6.67), mother with asthma (OR = 1.84; 95% CI = 1.11-3.05), current exposure to pets (OR = 1.83; 95% CI = 1.45-2.32) and passive tobacco smoking exposure (OR = 1.43; 95% CI = 1.12-1.83). Our results show that genetic background, environmental factors and the presence of co-morbidities such as rhinitis and atopic eczema are associated to the genesis of asthma in Brazilian schoolchildren.

Effect of nasal steroid treatment on airway inflammation determined by exhaled nitric oxide in allergic schoolchildren with perennial rhinitis and asthma

Rhinitis is common in asthmatic schoolchildren who are allergic to animal dander and constantly and indirectly exposed to these allergens in their everyday environment. As a patho-physiological linkage between nasal and bronchial inflammation has been proposed to exist, the primary objective of this study was to determine whether nasal administration of mometasone furoate (MSNF) can reduce bronchial inflammation, as reflected in the level of exhaled nitric oxide (F(E)NO) in asthmatic schoolchildren with dander allergy and mild-to-moderate rhinitis. Forty such children were assigned randomly to be treated for 4 wk with MSNF or placebo, employing a double-blind procedure. F(E)NO was the primary end-point measured and secondary end-points were nasal levels of NO, the concentration of eosinophilic cationic protein (ECP) in nasal lavage, the relative numbers of eosinophils in blood, forced expiratory volume in 1 s (FEV(1)), peak expiratory flow (PEF) and scoring of symptoms. There was no significant difference in the F(E)NO values of the treated and control groups at any time-point, whereas the nasal level of ECP was lower in the treated group compared with placebo (p = 0.05) on both days 7 and 28, and compared with baseline for the treated group (p = 0.06 on day 7, p = 0.02 on day 28). Furthermore, the mean blood eosinophil count decreased in the treated group, which also demonstrated lower scores for nasal symptoms compared with placebo, but neither of these differences were statistically significant. FEV(1), PEF and nasal levels of NO remained unchanged in both groups. Four weeks of nasal treatment with MSNF had no effect on bronchial inflammation, as reflected by exhaled NO, whereas signs of nasal and systemic eosinophil activation were reduced. Thus, nasal administration of a steroid as a strategy to reduce asthmatic inflammation remains questionable in mild-to-moderately severe cases of perennial rhinitis and asthma.

Neonatal characteristics and risk of atopic asthma in schoolchildren: results from a large prospective birth‐cohort study

Asthma is among the most common chronic diseases in childhood and steadily increasing in prevalence. Identification of risk predictors for a hospitalization for atopic asthma in childhood may help design prevention programmes and improve our understanding of disease pathobiology. An ongoing birth-cohort study prospectively enrolled all liveborn infants in Tyrol. Between 1994 and 1999 baseline data were collected for 33,808 infants. From 2000 to 2005, all children hospitalized for atopic asthma at an age of 6 years or over (n = 305) were identified in a careful search of hospital databases. Disease status was ascertained from the typical medical history, a thorough examination and proof of atopy. Male sex (relative risk 2.11, 95% CI 1.65-2.70), urban living environment (vs. rural) (1.93, 1.47-2.54), neonatal admission to hospital (1.70, 1.20-2.40), lack of breastfeeding (1.32, 1.02-1.70), postnatal smoking (1.31, 1.00-1.72) and low birth weight (1.45, 0.94-2.23) all emerged as adverse risk predictors for hospitalization for atopic asthma whereas a low risk was found among children living on a farm (0.22, 0.05-0.87) and children with two to three siblings (vs. no or one sibling) (0.71, 0.51-0.97). In this study a number of neonatal characteristics and environmental exposures were associated with hospitalization for atopic asthma in childhood, suggesting that early life is crucial for disease determination and lending further indirect support to the hygiene hypothesis.

Ecological study of socio-economic indicators and prevalence of asthma in schoolchildren in urban Brazil

BackgroundThere is evidence of higher prevalence of asthma in populations of lower socio-economic status in affluent societies, and the prevalence of asthma is also very high in some Latin American countries, where societies are characterized by a marked inequality in wealth. This study aimed to examine the relationship between estimates of asthma prevalence based on surveys conducted in children in Brazilian cities and health and socioeconomic indicators measured at the population level in the same cities.MethodsWe searched the literature in the medical databases and in the annals of scientific meeting, retrieving population-based surveys of asthma that were conducted in Brazil using the methodology defined by the International Study of Asthma and Allergies in Childhood. We performed separate analyses for the age groups 6–7 years and 13–14 years. We examined the association between asthma prevalence rates and eleven health and socio-economic indicators by visual inspection and using linear regression models weighed by the inverse of the variance of each survey.ResultsSix health and socioeconomic variables showed a clear pattern of association with asthma. The prevalence of asthma increased with poorer sanitation and with higher infant mortality at birth and at survey year, GINI index and external mortality. In contrast, asthma prevalence decreased with higher illiteracy rates.ConclusionThe prevalence of asthma in urban areas of Brazil, a middle income country, appears to be higher in cities with more marked poverty or inequality.

Identification of asthmatic children using prescription data and diagnosis

The aim of the study was to develop and validate a method for identifying asthmatic children between 6 and 14 years of age based on prescription data on anti-asthmatic drugs and diagnostic data. A register-based study of 125,907 Danish children aged 6-14 years identified 9695 children who had redeemed at least one anti-asthmatic drug prescription in 2002. The asthma diagnosis in these children was validated by discharge information and by a questionnaire completed by general practitioners. Models based on combinations of different types of drugs were tested to find the best model that would include as many children as possible with a validated diagnosis and exclude as many false positives as possible. Different time windows were tested in terms of detecting the children and the observation period of refilling prescriptions. The highest specificity of 0.86 [95% confidence interval (95% CI): 0.84-0.87] together with a sensitivity of 0.63 (95% CI: 0.62-0.65) were found in the model that included children who had redeemed a prescription for any anti-asthmatic drug - with the exception of prescriptions for beta2-agonists as liquid, one prescription only of inhaled beta2-agonist or an inhaled steroid - during a 12-month period. Lengthening the observation time by 6 months did not significantly improve the specificity (0.87; 95% CI: 0.85-0.88), but it did result in a statistically significantly lower sensitivity (0.59; 95% CI: 0.58-0.60). Register-based data on redeemed prescriptions can be utilised to identify asthmatic school children. This method will be useful in health services research and in the proactive care of asthmatic children.

The Association of Diet with Respiratory Symptoms and Asthma in Schoolchildren in Taipei, Taiwan

This study aimed to evaluate the association of diet with respiratory symptoms and asthma in schoolchildren in Taipei, Taiwan. An in-class interview survey elicited experiences of asthma and respiratory symptoms and consumption frequencies of the major food categories in 2290 fifth graders. Respiratory symptoms surveyed included persistent cough, chest tightness, wheezing with cold, wheezing without cold, dyspnea-associated wheezing, and exercise-induced cough or wheezing. Results showed that the consumption of sweetened beverages had the strongest association with respiratory symptoms and was positively associated with six of the seven respiratory symptoms (all p < 0.05). The adjusted odds ratios (aOR) ranged from 1.05 (95% confidence interval (CI = 1.01–1.09) for exercise-induced cough to 1.09 (95% CI = 1.03–1.16) for wheezing without cold. Egg consumption was associated with 5 of the 7 respiratory symptoms. Consumptions of seafood, soy products, and fruits were each negatively associated with one of the seven respiratory symptoms (all p < 0.05). Consumption of seafood was negatively associated with physician-diagnosed asthma and consumptions of sweetened beverages and eggs were positively associated with suspected asthma (p < 0.05). In conclusion, the study suggests that diet is associated with the respiratory symptoms in schoolchildren in Taipei. Consumptions of sweetened beverages and eggs are associated with increased risk of respiratory symptoms and asthma whereas consumptions of soy products and fruits are associated with reduced risk of respiratory symptoms.

The Shuttle Run Test Is Not Valid For the Detection of Asthma in School Physical Education Programs

Certain sporting activities may trigger asthma exacerbations of varying intensity in children. Such exacerbations may lead to limitations in and rejection of such activities. During school hours, teachers are in a good position to observe these phenomena. The aim of the present study was to evaluate the shuttle run, a test of physical fitness used in school physical education programs, as a way of detecting asthma. We carried out a cross-sectional observational study of school children between the ages of 6 and 12 years using the asthma symptom questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC), a shuttle run test, and a free running test at maximum effort in order to study bronchial hyperresponsiveness. The principal measure of bronchial hyperresponsiveness used in both physical fitness tests was peak expiratory flow rate as measured with a peak flow meter. In comparing the results of the shuttle run test with those of the free running test and the ISAAC questionnaire we used the chi(2) test to measure association and the Cohen kappa coefficient to measure agreement. We distributed the ISAAC questionnaire (n=919) to 460 (50.1%) boys and 459 (49.9%) girls between the ages of 6 and 12 years. All the tests were completed by 826 children. The level of agreement between the shuttle run test and free running test was positive but low for decreases in peak expiratory flow rate compared to baseline of 15% (chi(2)=5.6; P< .05; kappa=0.093; SE, 0.042) and of 20% (chi(2)=4.5; P< .05; kappa=0.08; SE, 0.046). For 10% decreases association was not significant and agreement was low (kappa=0.05; SE, 0.04). There was no agreement between the ISAAC questionnaire and the shuttle run test (kappa=0.095; SE, 0.63). The shuttle run test using peak expiratory flow rate as the principal measure of bronchial hyperresponsiveness is not valid for the detection of asthma in schoolchildren.

Hipersensibilidade a fungos em crianças asmáticas de uma comunidade do Recife, Pernambuco

OBJETIVOS: identificar a sensibilização a testes cutâneos de hipersensibilidade imediata para fungos em crianças asmáticas, residentes em comunidade urbana de baixa renda. MÉTODOS: no período de março de 1997 a junho de 1998 foram avaliadas 13 crianças com mais de três episódios de dispnéia nos últimos 12 meses, selecionadas a partir de um estudo transversal, em que todos os 123 escolares de 6 a 10 anos residentes na comunidade responderam ao questionário International Study of Asthma and Allergies in Childhood. Nas 13 crianças com asma em atividade, foram aplicados testes cutâneos de hipersensibilidade imediata para avaliar resposta a seis extratos fúngicos padronizados: Aspergillus mix, Penicillium mix, Hormodendrum cladosporidiodes, Alternaria tenius, Helminthosporium interseninatum e Mold mix. RESULTADOS: dentre as 13 crianças analisadas, 12 apresentaram sensibilididade a pelo menos um dos fungos testados (12/13), cujos extratos com maior frequência de positividade foram: Aspergillus mix (7/13), Penicillium mix (6/13) e Hormodendrum cladosporidiodes (5/13). CONCLUSÕES: a freqüência elevada de hipersensibilidade aos extratos de fungos nas crianças avaliadas sugere a necessidade de estudos analíticos observacionais para esclarecer uma possível associação causal entre fungos e asma.

The Relationship of Breastfeeding, Overweight and Asthma in School Children

RATIONALE: Breastfeeding may be a protective factor for childhood overweight and asthma. However, few studies have investigated the interactive relationship between breastfeeding and overweight in the development of asthma.

Importance of the personal endotoxin cloud in school-age children with asthma

A number of studies have observed associations between the amount of endotoxin in urban dust and chronic asthma severity, but a direct relationship between personal exposure to household endotoxin and acute asthma worsening has not yet been defined. We sought to investigate the relationship between day-to-day changes in personal endotoxin exposure and asthma severity. In the winter and spring of 1999 through 2000, endotoxin exposures were monitored in asthmatic schoolchildren by using portable, as opposed to stationary, monitors designed to measure inhalable and respirable particulate matter less than or equal to 2.5 and 10 microm in diameter. Children were followed with daily measurements of FEV(1) and asthma symptoms. Over a 24-hour period, median daily personal endotoxin exposures ranged from 0.08 EU/m(3) (measured at a particulate matter size range </=2.5 microm in diameter) to 0.37 EU/m(3) (measured at a particulate matter size range </=10 microm in diameter). Personal exposures were significantly (P < .001) higher than endotoxin measurements from either indoor or outdoor stationary monitors. Moreover, individual exposures did not correlate with stationary measurements, suggesting that exposures derived from sources in close proximity to the children's personal activities might be better correlated with disease severity. Increases in personal endotoxin exposures were associated with decreased FEV(1) values and increased symptoms. These findings demonstrate the importance of using personal monitoring to both measure and correlate endotoxin exposure with asthma severity.

A Comparative Study of Self Concept and Related Factors in Asthmatic and Healthy Schoolchildren

Objective: With a positive self concept, asthmatic schoolchildren are likely to accomplish self-management behaviors. The purpose of this study was, therefore, to investigate the self concept of school age children with and without asthma, and probe related factors. Materials and Methods: The subjects, 150 fourth to sixth graders of whom 50 were asthmatic and 100 were healthy, were purposively selected from a pediatric allergy outpatient clinic in a medical center in northern Taiwan. The research tools included a structured questionnaire, the ”Self Concept Scale” and the ”Parenting Style Scale”. Data were analyzed by descriptive and inferential statistics using SPSS for Windows/PC 10.0 software and StatXact-5 statistical software. Results: There was a significant difference between the self concept of asthmatic and healthy schoolchildren. Asthmatic children's overall self concept (p＜0.01), self concept family subscale (p＜0.05), and self concept physical subscale (p＜0.001) were lower than those of healthy children. Asthmatic children's limits in physical education class were significantly correlated with overall self concept, whereas the overall self concept was highest for children with full class attendance (p＜0.05) and no shortness of breath after exercise (p＜0.01). After modifying for the group effect, the parenting style and overall self concept were positively correlated (p＜0.001). Conclusions: These research results can serve as guidelines for medical care professionals, parents, and teachers, in caring for and teaching asthmatic and healthy schoolchild.

Prevalence and risk factors for asthma in schoolchildren in southern Brazil

To study the prevalence and risk factors for asthma in a cohort of 494 children born in 1993 and followed up to the age of six years in Pelotas, state of Rio Grande do Sul, Brazil. A standardized and validated asthma questionnaire, based on the International Study of Asthma and Allergies in Childhood (ISAAC), was applied. Other information was also collected about socioeconomic background, genetic, nutritional, gestational and allergic factors, and previous infectious episodes. The prevalence of asthma found in this study was 12.8% (95%CI: 10-15.9%). In the multivariate analysis, risk factors such as non-white skin color (RR = 1.9 95% CI: 1.1-3.3%), family history of asthma (RR = 2.8 95% CI: 1.5-5.1), allergic rhinitis in children (RR = 2.6 95% CI: 1.5-4.4) and maternal smoking during pregnancy (RR = 1.7 95%CI: 1-2.9) were associated with asthma. Childhood asthma is highly prevalent in Pelotas, and it is a serious public health problem. Therefore, specific programs should be developed for its control.

Exhaled Nitric Oxide Predicts Exercise-Induced Bronchoconstriction in Asthmatic School Children

Exercise-induced bronchoconstriction (EIB) is of particular importance in children with asthma. It is an important measure of asthma control and should be monitored by exercise testing. However, exercise testing puts a large demand on health-care resources and is therefore not widely used in routine monitoring of pediatric asthma control. The fractional concentration of exhaled nitric oxide (FeNO) also reflects uncontrolled asthma. We hypothesized that FeNO may be used for prescreening of asthmatic children to exclude those with good asthma control unlikely to have EIB, thereby reducing the need for exercise testing. The aim of this study was to estimate the value of FeNO as a predictor of EIB in asthmatic children. Stable outpatient asthmatic school children performed standard exercise challenge tests and measurement of FeNO. FeNO and response to a standardized submaximal exercise test on the treadmill were measured in 111 school children with asthma. EIB could be excluded with a probability of 90% in asthmatic children with FeNO levels < 20 parts per billion (ppb) without current inhaled corticosteroid treatment, and < 12 ppb in children with current inhaled corticosteroid treatment. Measurement of FeNO is a simple, and time- and resource-efficient tool that may be used to screen for EIB testing and therefore optimizes the resources for exercise testing in pediatric asthma monitoring.

Epidemiology of asthma in schoolchildren in Portuguese speaking regions

Abstract Asthma in schoolchildren became a priority both for developing and developed countries. Two large multi-centre epidemiological studies (Portuguese Study of Allergic Diseases in Childhood and the International Study of Asthma and Allergies in Childhood) were implemented in the last decade. One of the main objectives was to compare prevalence of asthma and evaluate cultural, ethnic and environmental variables in schoolchildren of different continents. These studies can contribute to a global strategy (with national specificity's) including self management programs in the control of asthma to reduce the morbidity and mortality, and promote better quality of life with better allocation of resources.

Exhaled nitric oxide as a screening tool for asthma in school children

It is now widely accepted that augmented levels of fractional exhaled nitric oxide (FeNO) reflect airway inflammation and the methodology has been optimised for potential clinical use. We were interested in investigating whether this measurement can be used as a tool to screen and identify school children with asthma. To do this, FeNO was measured using an on-line single exhalation analyser in 368 children aged 8-10 years in six Oxfordshire primary schools, by two investigators blinded to the disease status of the children. The children were then categorised into 'normal', 'atopic asthma', 'non-atopic asthma' and 'atopy only' groups, according to their responses to the ISAAC questionnaire and perusal of the children's medical records kept by their family practitioners. Increased levels of FeNO were found in 'atopic asthmatic', 'non-atopic asthmatics' and 'atopic only' groups (median values of 24.4, 7.8 and 15.3 ppb, respectively, compared to normal controls' of 6.9 ppb). Levels were increased in atopic children regardless of whether they had asthma and were significantly higher than non-atopic asthmatics. We conclude that FeNO measurement is not a useful tool for identifying children with asthma in the community, as increased levels did not discriminate between those with asthmatic and atopic symptoms.

Skin‐prick testing as a diagnostic aid for childhood asthma

Diagnosing asthma is problematic when based solely on reported symptoms. The purpose of this study was to evaluate skin-prick testing as a diagnostic aid for asthma in children. Skin-prick testing (SPT) was undertaken in children aged 2-10 years with either no history of wheeze (n = 149) or recent doctor-observed wheeze which responded to treatment with a bronchodilator, the "gold standard" (n = 164). Children with moderate or severe asthma were excluded. SPT positivity increased sharply at age 5 years in wheezers. Data were therefore divided into two age groups: 2- < 5 years (57 controls, 97 wheezers) and 5-10 years (92 controls, 67 wheezers). The sensitivity, specificity, and likelihood ratios of SPT positivity for wheeze were 32%, 89%, and 2.9, respectively, in the younger children, and 82%, 85%, and 5.5, respectively, in the older children. For a prevalence of 30% for asthma, the positive predictive values of a positive SPT were 55% and 70% for the younger and older age groups, respectively. The test characteristics of SPT for helping diagnose asthma in schoolchildren are good. The prevalence of wheeze in preschool children is high, and so SPT should be helpful even in this group. We suggest that clinicians consider skin-prick testing as a diagnostic aid for asthma.