Results of an inner-city school-based asthma and allergy screening pilot study: a combined approach using written questionnaires and step testing

The reliability and validity of the Turkish version of the school-based asthma and allergy screening questionnaires

BACKGROUND

Asthma is an important public health disease affecting children that may result in school absenteeism and hospitalization. This study aims to assess the validity, reliability, and diagnostic accuracy of the Turkish version of the asthma and allergy screening questionnaire.

METHODS

This study included primary and secondary school students from grades 2 to 7 and their parents or caregivers. For validity, 40 children with asthma and 39 children with allergies diagnosed by the questionnaire were used to determine the sensitivity. The specificity was calculated by using the data of 100 children without asthma and allergies. The study was completed with the participation of 704 students and parents. The intraclass correlation coefficient (ICC) was used to assess item reliability. Receiver operating characteristic (ROC) analysis was used to assess validity.

RESULTS

When the cutoff point of the questionnaire was 2/3 for asthma, the sensitivity was 80.0% and 82.5% and the specificity was 56.6% and 76.8% according to the student and parent form, respectively. When the cutoff point of the questionnaire was 0/1 for allergies, the sensitivity was 74.4% and 84.6% and the specificity was 66.3% and 54.2% according to the student (SQ) and parent questionnaire (PQ), respectively. The reliability of test-retest correlation values (≥0.68) of asthma and allergy questionnaires were found to be statistically significant. The internal consistency Cronbach's α values of the asthma SQ and PQ were 0.72 and 0.80, respectively.

CONCLUSIONS

According to the Turkish questionnaire for students and their parents, the sensitivity of asthma and allergy questionnaires was similar in proportion to the original questionnaire. The Turkish version of the questionnaire can be used for asthma and allergy screening in schools.

Air quality, Environment and Respiratory Outcomes in Bronchopulmonary Dysplasia, the AERO-BPD cohort study: design and adaptation during the SARS-CoV-2 pandemic

INTRODUCTION

Almost half of all school-age children with bronchopulmonary dysplasia (BPD) have asthma-like symptoms and more suffer from lung function deficits. While air pollution and indoor respiratory irritants are known to affect high-risk populations of children, few studies have objectively evaluated environmental contributions to long-term respiratory morbidity in this population. This study aimed to examine the role of indoor environmental exposures on respiratory morbidity in children with BPD.

METHODS AND ANALYSIS

The Air quality, Environment and Respiratory Ouctomes in BPD (AERO-BPD) study is a prospective, single-centre observational study that will enrol a unique cohort of 240 children with BPD and carefully characterise participants and their indoor home environmental exposures. Measures of indoor air quality constituents will assess the relationship of nitrogen dioxide (NO2), particulate matter (PM2.5), nitric oxide (NO), temperature and humidity, as well as dust concentrations of allergens, with concurrently measured respiratory symptoms and lung function.Adaptations to the research protocol due to the SARS-CoV-2 pandemic included remote home environment and participant assessments.

ETHICS AND DISSEMINATION

Study protocol was approved by the Boston Children's Hospital Committee on Clinical Investigation. Dissemination will be in the form of peer-reviewed publications and participant information products.

TRIAL REGISTRATION NUMBER

NCT04107701.

Current Asthma Prevalence Using Methacholine Challenge Test in Korean Children from 2010 to 2014

BACKGROUND

Most epidemiological studies depend on the subjects' response to asthma symptom questionnaires. Questionnaire-based study for childhood asthma prevalence may overestimate the true prevalence. The aim of this study was to investigate the prevalence of "Current asthma" using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and methacholine challenge test in Korean children.

METHODS

Our survey on allergic disease included 4,791 children (age 7-12 years) from 2010 to 2014 in Korean elementary schools. Bronchial hyperresponsiveness (BHR) was defined as provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (FEV1) (PC20) ≤ 16 mg/mL. "Current asthma symptoms" was defined as positive response to "Wheezing, current," "Treatment, current," or "Exercise, current." "Current asthma" was defined when the subjects with "Current asthma symptoms" showed BHR on the methacholine challenge test or had less than 70% of predicted FEV1 value.

RESULTS

The prevalence of "Wheezing, ever," "Wheezing, current," "Diagnosis, ever," "Treatment, current," "Exercise, current," and "Current asthma symptoms" was 19.6%, 6.9%, 10.0%, 3.3%, 3.5%, and 9.6%, respectively, in our cross-sectional study of Korean elementary school students. The prevalence of BHR in elementary school students was 14.5%. The prevalence of BHR in children with "Wheezing, ever," "Wheezing, current," "Diagnosis, ever," "Treatment, current," and "Exercise, current" was 22.3%, 30.5%, 22.4%, 28.8%, and 29.9%, respectively. BHR was 26.1% in those with "Current asthma symptoms." The prevalence of "Current asthma" was 2.7%.

CONCLUSIONS

Our large-scale study provides 2.7% prevalence of current asthma in Korean elementary school children. Since approximately one third of the children who have "Current asthma symptoms" present BHR, both subjective and objective methods are required to accurately predict asthma in subjects with asthma symptoms.

Allergy screening in a schoolchildren-based population

BACKGROUND

Schoolchildren screening for allergic diseases may improve early identification and management of atopic children. The aim of this study was to perform a schoolchildren screening program for identification of children with allergic diseases.

METHODS

All parents of children attending to 13 primary schools in the city of Rome were requested to fill in a demographic data form and the ChAt questionnaire. Allergological evaluation was performed in the children with suspect of allergy (ChAt score > 2). Ocular examination was performed to identify signs of allergic conjunctivitis. The presence of allergic symptoms was related to demographic and environmental variables.

RESULTS

A total of 2667 children (mean age: 7.1 ± 1 years) were included, and 2489 (93.3%) parents completed the ChAt questionnaire. Results of ChAt questionnaire showed a previous diagnosis of allergic disease in 637 (25.6%) children and the potential presence of an allergic disease (ChAt score > 2) in 35.1%. Multivariate analysis showed that older age, male gender, and having less than two siblings were associated with higher risk of allergic disease. Visual screening showed the presence of clinical signs of allergic conjunctivitis in 2% of children. Allergologic evaluation in 334 children confirmed the diagnosis of allergic disease in 324 (97%) cases. Among them, 97 (29.9%) did not refer to a previous formal diagnosis of allergic condition.

CONCLUSIONS

This study confirmed that schoolchildren screening using ChAt questionnaire could represent a useful tool for early identification of yet undiagnosed atopic children.

Particularities of allergy in the Tropics

Allergic diseases are distributed worldwide and their risk factors and triggers vary according to geographical and socioeconomic conditions. Allergies are frequent in the Tropics but aspects of their prevalence, natural history, risk factors, sensitizers and triggers are not well defined and some are expected to be different from those in temperate zone countries. The aim of this review is to investigate if allergic diseases in the Tropics have particularities that deserve special attention for research and clinical practice. Such information will help to form a better understanding of the pathogenesis, diagnosis and management of allergic diseases in the Tropics. As expected, we found particularities in the Tropics that merit further study because they strongly affect the natural history of common allergic diseases; most of them related to climate conditions that favor permanent exposure to mite allergens, helminth infections and stinging insects. In addition, we detected several unmet needs in important areas which should be investigated and solved by collaborative efforts led by the emergent research groups on allergy from tropical countries.

Validation of a questionnaire for asthma case identification in pre-schools in Latin America

BACKGROUND AND OBJECTIVE

We recently developed and validated a screening questionnaire for determining which school-aged children may need further investigation to diagnose and manage asthma. In the present study we sought to extend this to pre-school aged children.

METHODS

Questions from the school-aged questionnaire and literature on pre-school asthma were used to inform a focus group of parents with pre-school-aged children with asthma to develop a screening questionnaire. Parents of children attending 6 randomly selected kindergartens in Trelew, Argentina (n = 639) were invited to respond to the questionnaire. A reliability test-retest was undertaken in 187 randomly selected parents who completed the same questionnaire twice within 2-5 weeks. Clinical assessment included a standardized history and physical examination, spirometry before and after a β-agonist inhaler, and chest X-ray. Asthma was diagnosed by the pulmonologist.

RESULTS

Completed surveys were returned for 620 children, 607 of whom underwent clinical evaluation. The mean age was 4.21 years (range of 3.01-5.50) and included 82.5% white and 49.4% male children. Asthma was diagnosed in 103 (17.0%) children); 72 (69.9%) of these children did not have a previous diagnosis of asthma. The specificity, sensitivity, positive predictive value and negative predictive value of the questionnaire were 93.2%, 86.1%, 57.8% and 98.4%, respectively.

CONCLUSIONS

We have demonstrated the utility of a screening questionnaire for identifying pre-school-aged children who may benefit from further assessment for asthma.

Introducing an environmental assessment and intervention program in inner-city schools

Home-based environmental interventions have demonstrated clinical benefit for children with asthma. Although much is known about school-based exposures, few studies have comprehensively examined the role the school environment plays in asthma and how effectively changing the environment might reduce morbidity when adjusting for exposures in the home. This review summarizes the importance and common challenges of school-based environmental assessment and intervention studies linked to health effects. We focus on the key components of study development and the challenges and benefits to implementation.

Validation of a school-based written questionnaire for asthma case identification in Argentina

Recognition of asthma in community-based surveys can be problematic. We sought to develop and validate questionnaires that could identify elementary school-aged children likely to have asthma or who had poorly-controlled asthma. Questionnaires for parents (PQ) and students (SQ) to complete were developed using guidance on question wording from a focus group consisting of children with asthma and their parents. The gold standard for this study was a pulmonologist determination of asthma and this was used to calculate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for each question and for combinations of questions. Questionnaires were distributed to 830 children attending elementary schools in Trelew, Argentina and 96% were returned. Test-retest reliability was determined in 221 randomly selected parents and children and very good levels of agreement were seen for individual questions. Asthma was diagnosed in 92 students. Overall, the PQ was able to detect asthma better than the SQ. Optimal diagnostic ability came by combining questions from the PQ and SQ. Not surprisingly, these questionnaires had a better NPV than PPV and can be used to determine which children require further evaluation.

Risk factors for allergic rhinitis in Costa Rican children with asthma

BACKGROUND

Risk factors for allergic rhinitis (AR) in asthmatics are likely distinct from those for AR or asthma alone. We sought to identify clinical and environmental risk factors for AR in children with asthma.

METHODS

We performed a cross-sectional study of 616 Costa Rican children aged 6-14 years with asthma. Candidate risk factors were drawn from questionnaire data, spirometry, methacholine challenge testing, skin testing, and serology. Two outcome measures, skin test reaction (STR)-positive AR and physician-diagnosed AR, were examined by logistic regression.

RESULTS

STR-positive AR had high prevalence (80%) in Costa Rican children with asthma, and its independent risk factors were nasal symptoms after exposure to dust or mold, parental history of AR, older age at asthma onset, oral steroid use in the past year, eosinophilia, and positive IgEs to dust mite and cockroach. Physician-diagnosed AR had lower prevalence (27%), and its independent risk factors were nasal symptoms after pollen exposure, STR to tree pollens, a parental history of AR, inhaled steroid and short-acting beta2 agonist use in the past year, household mold/mildew, and fewer older siblings. A physician's diagnosis was only 29.5% sensitive for STR-positive AR.

CONCLUSIONS

Risk factors for AR in children with asthma depend on the definition of AR. Indoor allergens drive risk for STR-positive AR. Outdoor allergens and home environmental conditions are risk factors for physician-diagnosed AR. We propose that children with asthma in Costa Rica and other Latin American nations undergo limited skin testing or specific IgE measurements to reduce the current under-diagnosis of AR.

Prevalence of self-perceived allergic diseases and risk factors in Italian adolescents

The aim of the study was to assess the symptoms prevalence of allergic diseases in a population of 11-15 yr old schoolchildren, to evaluate the associations between asthma and other symptoms and identify risk factors for asthma, rhinitis and eczema syndromes. A sample of 481 students was studied using an International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Prevalence of different kind of self-reported symptoms was calculated. Using a logistic regression approach, we tried to identify risk factors for three syndromes - rhinitis, eczema and asthma. The highest and the lowest prevalence rates of self-reported symptoms were recorded for rhinitis (43.6%) and for eczema (8.1%), respectively. The prevalence of asthma was 15.7%. Univariate analysis showed a mutual association between wheeze and rhinitis symptoms. Multivariate logistic regression model for eczema syndrome revealed female gender as a significant risk factor. The polytomic logistic multivariate regression revealed female gender and family history of allergy as significant risk factors for rhinitis syndrome only, and maternal smoking and familial allergy for rhinitis and asthma together. In particular, familial allergy yields a 400% higher chance of developing asthma and rhinitis together. The synergistic effect of familial allergy on rhinitis and asthma syndromes suggests the implementation of preventive measures in children with family history of these diseases.

Association of atopy, asthma, allergic rhinoconjunctivitis, atopic dermatitis and intestinal helminth infections in Cuban children

OBJECTIVE

To examine the relationship of past and current intestinal helminth infections with asthma, allergic rhinoconjunctivitis, atopic dermatitis and atopy.

METHODS

Cross-sectional study of 1320 children aged 4-14 years from two Cuban municipalities. Helminth infections were determined by stool examination and parental questionnaire. Asthma, rhinoconjunctivitis and atopic dermatitis were diagnosed by International Study of Asthma and Allergies in Childhood questionnaire, asthma additionally by spirometry, atopy by skin prick testing.

RESULTS

Questionnaire-based frequencies were 21% for asthma, 14% for allergic rhinoconjunctivitis and 8% for atopic dermatitis. According to spirometry, 4% had asthma; 20% had a positive skin prick test. A history of infection for Enterobius vermicularis was associated with increased risk of atopic dermatitis (OR 1.88, P = 0.001) and allergic rhinoconjunctivitis (OR 1.34, P = 0.046), and hookworm with increased risk of allergic rhinoconjunctivitis (OR 2.77, P = 0.021). A positive stool examination for Ascaris lumbricoides infection was negatively associated with atopic dermatitis (OR 0.22, P = 0.007). Asthma and atopy were unrelated to helminth infections.

CONCLUSION

Current A. lumbricoides infection protects against atopic dermatitis in Cuban children, while past infection with E. vermicularis and hookworm are risk factors for allergic rhinoconjunctivitis and/or atopic dermatitis. Apparently, interactions differ depending on the type of helminth and atopic disease and on the time of helminth infestation.

Prevalence of childhood asthma and control in children assessed in a pilot school-based intervention programme in Singapore

AIM

Because of a high childhood asthma burden in Singapore, assessment of disease control status is essential for formulating school-based strategy of childhood asthma control. The aim of the present study is to assess childhood asthma prevalence and control in Singapore and the socio-demographic and help-seeking correlates.

METHODS

School-based survey using parental self-administered questionnaire, conducted from February to April 2004. Four mixed-gender primary schools selected from geographically distinct zones of Singapore. All primary one (modal age - 6.5 years) and six (modal age - 11.9 years) students from selected schools were invited to participate. Questionnaire respondents were the students' parents or guardians. The response rate was 75.2% (2123/2825).

RESULTS

Prevalence of current asthma was 8.9% (190/2123). Among them, 26.3% (46/175) were assessed to have inadequate control. Asthma was more prevalent, and less adequately controlled in children from lower socio-economic backgrounds (lower-end housing type). Children with poorly controlled asthma were more likely to be treated by emergency room physicians and hospital specialists, and to be on preventer medications.

CONCLUSIONS

In Singapore, poor asthma control is found in a sizeable proportion of school children with asthma, is identifiable for high-risk groups of children from lower socio-economic backgrounds and having asthma-related attendance at the emergency rooms.

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.

The challenge of diagnosing atopic diseases: outcomes in Cuban children depend on definition and methodology

BACKGROUND

Prevalences of childhood asthma and other atopic diseases are increasing worldwide, and so is the number of diagnostic methods and definitions used. We determined the occurrence of atopic diseases in Cuban children with a range of diagnostic approaches commonly used or proposed in epidemiological studies, and compared the different outcome measures.

METHODS

A total of 398 Cuban schoolchildren between 5 and 13 years of age were diagnosed by International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, clinical examination, pre- and post-exercise spirometry, and skin prick testing. All results were considered separately, as well as jointly by using scores and definitions as described in the literature.

RESULTS

Using questionnaire-based approaches, 21-39% of the children were positive for asthma, 9-19% for atopic dermatitis, and 15-46% for rhinoconjunctivitis. With spirometry, 7% of the children had asthma. Definitions based on a combination of questionnaire and spirometry results yielded asthma rates of 5%. Of all children, 6% wheezed on clinical examination, and only one child showed clinical signs of atopic dermatitis. Eleven percent of the children had a positive skin prick test. In total, 254 children (64%) had an atopic disease as based on the ISAAC questionnaire, and 263 (66%) based on all approaches used.

CONCLUSION

Diagnostic outcomes on atopic diseases vary considerably depending on definition and methodology. Our results clearly demonstrate the need for consensus on diagnosing asthma and other atopic diseases in epidemiological studies. Based on the most commonly used ISAAC questionnaire, our data suggest prevalences of atopic diseases in Cuban children that rival those found in some other Latin American countries and developed nations with the highest prevalences in the world.

Epidemiologic characteristics of rhinitis in Turkish children: the International Study of Asthma and Allergies in Childhood (ISAAC) phase 2

Rhinitis is a common problem with important comorbidities. In order to search the association between rhinitis, allergic phenotypes and other risk factors in Turkish children, a parental questionnaire about allergic diseases and risk factors, and skin prick test (SPT) with 13 inhalant allergens were performed in a population-based sample of 2774 children aged 9-11 yr. Bronchoprovocation testing with hypertonic saline (HS)and total IgE analysis were limited to a subsample of 350 children. Rhinitis was defined as a problem with sneezing, rhinorrhea, or nasal congestion when the child did not have a viral respiratory infection. The prevalences of ever rhinitis, current (last 12 months) rhinitis (CR), and ever hay fever were 36.3%, 30.6%, and 8.3%, respectively. SPT positivity rate was 20.4% among children with CR. Current wheezing and flexural dermatitis were significantly associated with CR. CR significantly increased the risk of asthma among both atopic and non-atopic subjects [odds ratio (OR), 3.98; 95% CI, 1.81-8.76; and OR, 2.79; 95% CI, 1.82-4.26, respectively]. The association between CR and bronchial hyperreactivity (BHR) was not significant. The multiple logistic regression analysis revealed family atopy (OR=2.25, 95% CI=1.79-2.83, p<0.001), current indoor heating with gas stove (OR=1.78, 95% CI=1.18-2.64, p=0.006) and dampness/molds at home during the first year of life (OR=1.70, 95% CI=1.25-2.31, p=0.001) as significant risk factors for CR. Turkish school children showed a high prevalence of rhinitis with a preponderance of non-atopics. The highly significant association between rhinitis and asthma independent of atopic sensitization emphasize the importance of non-atopic forms of rhinitis.

Making the diagnosis of asthma in the athlete

This article encompasses a discussion of the clinical presentation and features as various diagnostic modalites of bronchoprovocation and differential diagnosis used in screening for asthma in the athlete. A comparative analysis of these modalities, including questionnaire, treadmill, eucapneic hyperventilation, as well as field challenge, is provided with sensitivities and specificities, predictive value, and application to clinical practice. The indication and mechanics of each diagnostic modality is discussed, providing the clinician with a comprehensive understanding of the principles and procedures used to diagnosis asthma in the athlete.

Asthma in rural America

OBJECTIVES

To examine current trends of asthma prevalence, diagnosis, and utilization of care in rural areas, increase awareness about asthma disease burden, and provide general recommendations for improving care in this setting.

DATA SOURCES

MEDLINE searches were conducted for articles published from 1966 onward, with human subjects and the English language as descriptors. Other terms used included undiagnosed frequent wheezing, hygiene hypothesis, atopic sensitization, endotoxin, telemedicine, and asthma prevalence and care in rural or urban areas.

STUDY SELECTION

Review and original research studies that reported on asthma care in rural areas were selected for evaluation.

RESULTS

Contrary to common belief, evidence suggests that asthma prevalence of rural and urban youth is comparable in the United States and may indeed be higher in rural areas. Data are not available to determine prevalence rates for rural adults in the United States. This review presents data suggesting that the utilization of asthma care among rural and urban residents may not be comparable. Rural residents are confronted with certain barriers to care that are not as common in the urban setting. These include lack of health care insurance, geographic obstacles to obtaining care, inability of getting suitable appointments, scarcity of health care professionals, and poor access to information about asthma.

CONCLUSIONS

Current literature suggests that asthma in rural areas may be underdiagnosed and deserves additional study. Improving formal and continuing education of health care professionals, compensating for health care shortages by using existing resources, and facilitating patient support and education are some of the ways to address the special needs faced by rural residents.

School-based asthma surveillance: a comparison of student and parental report

This study addressed the comparability of data obtained from a student-based and parent-based asthma and respiratory health survey. Our goal was to ascertain whether there were meaningful and systematic differences in asthma classification based on symptom and diagnosis reports obtained separately from students and their parents. A brief, written survey, based on the International Study of Asthma and Allergy in Children questionnaire, was administered to 6th through 10th grade students in two schools in Oakland, CA, USA. Students who reported asthma-like indicators for the previous 12-month period were defined as positive and a more extensive questionnaire was mailed home to those parents. A more refined classification of asthma based on parent report of indicators was compared with student report. Forty-four percent of 1298 students were classified as positive for current asthma-like symptoms and 50% of parent surveys were returned. For the positive students with parent surveys, 59% were classified as 'probable' for asthma based on the parent survey. Overall, the agreement between parent and students' classification was 70%, and 83% for students with a parent report of physician diagnosis of asthma. Students who were discordant with parents for physician diagnosis of asthma were more likely to be male, and more likely to have a parent report of unscheduled Emergency Department visit for wheezing or trouble breathing. Findings indicated that with the exception of medication, students reported asthma indicators more frequently that parents, independent of classification. Student report of physician diagnosis with a 12-month report of an asthma symptom was determined to be a good indicator of probable current asthma. Inclusion of or reliance on a parental questionnaire is not likely to improve the reliability of a school-based asthma surveillance program in our population.

Clinically diagnosed childhood asthma and follow-up of symptoms in a Swedish case control study

Background

Childhood asthma has risen dramatically not only in the western societies and now forms a major and still increasing public health problem. The aims of this study were to follow up at the age of ten the patterns of asthma symptoms and associations among children with a clinically diagnosed asthma in a sizeable urban-rural community and to in compare them with demographic controls using a standardised questionnaire.

Methods

In a defined region in Sweden with a population of about 150 000 inhabitants, all children (n = 2 104) born in 1990 were recorded. At the age of seven all primary care and hospital records of the 1 752 children still living in the community were examined, and a group of children (n = 191) was defined with a well-documented and medically confirmed asthma diagnosis. At the age of ten, 86 % of these cases (n = 158) and controls (n = 171) completed an ISAAC questionnaire concerning asthma history, symptoms and related conditions.

Results

Different types of asthma symptoms were highly and significantly over-represented in the cases. Reported asthma heredity was significantly higher among the cases. No significant difference in reported allergic rhinitis or eczema as a child was found between cases and controls. No significant difference concerning social factors or environmental exposure was found between case and controls. Among the control group 4.7 % of the parents reported that their child actually had asthma. These are likely to be new asthma cases between the age of seven and ten and give an estimated asthma prevalence rate at the age of ten of 15.1 % in the studied cohort.

Conclusion

A combination of medical verified asthma diagnosis through medical records and the use of self-reported symptom through the ISAAC questionnaire seem to be valid and reliable measures to follow-up childhood asthma in the local community. The asthma prevalence at the age of ten in the studied birth cohort is considerably higher than previous reports for Sweden. Both the high prevalence figure and allowing the three-year lag phase for further settling of events in the community point at the complementary roles of both hospital and primary care in the comprehensive coverage and control of childhood asthma in the community.

Understanding the origin of asthma and its relationship to breastfeeding

Asthma is a chronic disease of the lung that has been increasing at an alarming rate in industrialized countries around the world over the last few decades. Although considerable progress has been made in our understanding of the underlying pathogenesis of the disease, the exact causes of the increasing prevalence are unknown. Studies suggest that most asthma develops in early childhood and that environmental factors present early in life may be crucial in the development of disease. One potential explanation for the recent epidemic referred to as the "hygiene hypothesis" postulates that factors that have resulted in a reduction in exposure to microbial products and/or infections in the western world may be contributing to this rise in disease prevalence. As early life influences are known to play an important role in establishment of asthma, studies have focused on the interface between mother and child that occurs during gestation and through breastfeeding. In this regard, the body of evidence regarding the relationship between breastfeeding and asthma indicates benefit but with the potential for risk. While providing population-level protection from infections and atopy in infancy and early childhood, breastfeeding might also pose an increased risk of atopic asthma among children with asthmatic mothers. In order to put this controversy in context, we discuss our current understanding of asthma pathogenesis, current theories on the factors driving the rising prevalence of asthma, and then discuss the potential influence of breastfeeding on asthma pathogenesis.

Validation of a multistage asthma case-detection procedure for elementary school children

OBJECTIVE

The purpose of this study was to validate a 3-stage asthma case-detection procedure for elementary school-aged children.

METHODS

The study was performed in 10 elementary schools in 4 inner-city school systems, with a total enrollment of 3539 children. Results of the case-detection procedure were compared with the diagnosis of an asthma specialist study physician, to determine the sensitivity and specificity of the case-detection procedure.

RESULTS

Ninety-eight percent of children returned the asthma symptoms questionnaires, and 79% of those children consented to additional testing. Results indicated that the 3-stage procedure had good validity, with sensitivity, specificity, and predictive value of 82%, 93%, and 93%, respectively. A 2-stage procedure using questionnaires and spirometry had similar validity, with sensitivity, specificity, and predictive value of 78%, 93%, and 93%, respectively. However, given the time and expense associated with the 2- or 3-stage procedure and the difficulty of obtaining physician follow-up evaluation of the case-detection diagnosis, schools may prefer to use a 2-item questionnaire that has a lower sensitivity (66%) but higher specificity (96%) and predictive value (95%).

CONCLUSIONS

Case-detection programs are generally well received by school personnel and can identify children with unrecognized or undiagnosed disease, as well as those with a current diagnosis but poorly controlled disease. This study yields substantial information regarding the validity, yield, and specific types of children who might be identified with the use of such procedures. For the choice of the method of case detection used in a school, the strengths and weaknesses of each procedure, as well as the resources available for case detection, physician referral, and follow-up procedures, must be considered.

Development and validation of school-based asthma and allergy screening questionnaires in a 4-city study

BACKGROUND

Asthma and allergies are commonly undiagnosed in children. Schools provide settings for potentially accessing almost all children for asthma and allergy screening.

OBJECTIVE

To evaluate the feasibility and validity of using a questionnaire-based screening tool to identify undiagnosed asthma and respiratory allergies in children in kindergarten to grade 6.

METHODS

A student questionnaire (SQ) and a parent questionnaire (PQ) were developed, administered in 4 diverse communities, and validated against standardized clinical assessments. Children without diagnosed asthma and representing a range of symptoms participated in a validation study that consisted of independent, standardized, clinical assessments. Sensitivity, specificity, and predictive values for questionnaire items were evaluated against expert consensus designations.

RESULTS

A total of 190 children (age range, 7-13 years) completed the validation study. Affirmative responses to individual questions from either the SQ or PQ regarding asthma and allergy were modestly to moderately predictive of the clinical assessments (odds ratios, generally 2.5-5.0). When considering a positive asthma screen as affirmative responses to 3 of the best 7 SQ asthma questions, the odds ratio for asthma was 9.3 (95% confidence interval, 4.1-21.1), with 80% sensitivity and 70% specificity. Considering the allergy screen as positive based on affirmative response to either of the 2 SQ allergy questions yielded 81% sensitivity and 42% specificity.

CONCLUSIONS

Either a 9-item SQ or a 10-item PQ can be used in diverse settings to screen for asthma and respiratory allergies. The SQ, obtained by directly screening students, may provide a sensitive approach for detecting children with previously undiagnosed asthma and allergies.

Prevalence and risk factors for allergic rhinitis and atopic eczema among schoolchildren in Israel: results from a national study

BACKGROUND

There is growing evidence that the prevalence rates of asthma and allergic diseases are increasing, especially among children. Several risk factors are under investigation.

OBJECTIVE

To evaluate the prevalence and risk factors for allergic diseases, including allergic rhinitis (AR) and atopic eczema (AE), among 13- to 14-year-old schoolchildren in Israel.

METHODS

A modified version of the International Study of Asthma and Allergies in Childhood written questionnaire was administered to a national sample of schoolchildren 13 to 14 years old in Israel. The questionnaire was completed by the schoolchildren themselves.

RESULTS

There were 10,057 complete questionnaires available for analysis. The prevalence of AR symptoms ever and current AR were 41.6% and 9.4%, respectively. Allergic rhinoconjunctivitis symptoms ever were reported by 15.8% of the children. The prevalence rates of 6 months of itchy rash ever and AE were 5.9% and 7.8%, respectively. After adjustment for demographic and environmental factors, current asthma, parental history of asthma, and population group were the most significant risk factors for current AR (odds ratio [OR], 4.47; 95% confidence interval [CI], 3.70-5.40; OR, 1.30; 95% CI, 1.02-1.66; and OR, 1.75; 95% CI 1.45-2.13; respectively) and AE (OR, 2.30; 95% CI, 1.80-2.90; OR, 1.80; 95% CI, 1.40-2.30; and OR, 1.70; 95% CI, 1.40-2.00; respectively).

CONCLUSIONS

Israeli children have a low prevalence rate of current AR and a midrange rate of AE. Arabs have lower prevalence rates of allergic diseases than Jews, and the prominent risk factors for those diseases are current asthma and parental history of asthma.

Indoor fungi levels in homes of children with and without allergy history

A study was performed at the four sentinel health departments of Baden-Württemberg between November 1999 and March 2000 to investigate the indoor levels of fungi at the homes of school children (mean age 10 y) and to describe possible associations with allergy statuses. Three hundred and ninety-seven households of school children with (n = 199) and without (n = 198) allergic history were included in the study. The median of colony forming units (CFU/m3) of fungi, measured in the children's bedrooms' in indoor air, was 105 (range 5 to 15,000), in outdoor air 110 (range 10 to 1500). The median of viable mould spores (CFU/g dust) in floor dust was 28,500 (range 1500 to 1,235,000), in mattresses 16,250 (range 0 to 2,500,000). Neither climatological conditions, nor differences between urban and rural regions showed a systematic influence on fungi counts. There was no difference in concentrations and distribution of fungi species levels between children with and without allergic history. The sensitization rate against molds (IgE) was higher for children with allergic condition (9.2%) than in control children (4.4%), but there was no association with the fungi counts in the rooms. In conclusion, the study defined the mould levels in children's rooms, but did not find an association with allergic history of the children or their sensitization rate.