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

Forced expiratory flows' contribution to lung function interpretation in schoolchildren

Forced expiratory flow (FEF) at low lung volumes are supposed to be better at detecting lung-function impairment in asthmatic children than a forced volume. The aim of this study was to examine whether FEF results could modify the interpretation of baseline and post-bronchodilator spirometry in asthmatic schoolchildren in whom forced expiratory volumes are within the normal range. Spirometry, with post-bronchodilator vital capacity within 10% of that of baseline in healthy and asthmatic children, was recorded prospectively. We defined abnormal baseline values expressed as z-scores <-1.645, forced expiratory volume in 1 s (FEV1) reversibility as a baseline increase >12%, FEF reversibility as an increase larger than the 2.5th percentile of post-bronchodilator changes in healthy children. Among 66 healthy and 50 asthmatic schoolchildren, only two (1.7%) children with normal vital capacity and no airways obstruction had abnormal baseline forced expiratory flow at 25-75% of forced vital capacity (FEF25-75%). After bronchodilation, among the 45 asthmatic children without FEV1 reversibility, 5 (11.1%) had an FEF25-75% increase that exceeded the reference interval. Isolated abnormal baseline values or significant post-bronchodilator changes in FEF are rare situations in asthmatic schoolchildren with good spirometry quality.

The outcome after severe bronchiolitis is related to gender and virus

The association between bronchiolitis in the first year of life and subsequent asthma, atopy, airway obstruction and bronchial hyper-responsiveness (BHR) is unsettled. Genetic predispositions, pre-morbid lung function, environmental interactions and altered immunological responses are risk factors that have been studied. The aim of this study was to assess lung function, BHR and the occurrence of asthma and atopy 11 yr after hospitalization for bronchiolitis in the first year of life, particularly focusing on the role of gender and virus involved. The study included 121 of 131 (92%) children hospitalized for bronchiolitis, 90 (74%) respiratory syncytial virus (RSV)-positive children and 141 children in an age-matched and unselected control group. At follow-up, current asthma was more common after RSV-negative bronchiolitis compared to controls (35.5% vs. 9.2%; p < 0.001), but not after RSV bronchiolitis (15.6%; p = 0.144). Higher BHR and an obstructive lung function pattern were observed after bronchiolitis, the latter most prominent after RSV-negative bronchiolitis. Higher BHR was confined to boys, but present in both the RSV-positive and RSV-negative groups (p = 0.007 and 0.003, respectively). Asthma after bronchiolitis was not associated with atopy. Atopy was similarly distributed between the RSV-positive and RSV-negative bronchiolitis groups and the control group. This study has shown that gender and type of virus are important factors to consider when addressing later development of asthma, BHR and lung function after hospitalization for bronchiolitis in early life.

Lung function changes in asthmatic children treated with HFA-BDP

STUDY OBJECTIVES

Asthma guidelines suggest that normal or near normal lung function should be one of the goals for good asthma control. Therefore, children with chronic persistent asthma and reduced peripheral airway function were assessed after the replacement of conventional inhaled corticosteroids (ICS) with an extrafine aerosol formulation, hydrofluoroalkane-134a beclomethoasone diproprionate (HFA-BDP).

DESIGN AND SETTING

Lung function and clinical details were studied in children with moderate persistent asthma who regularly attended the pediatric pulmonary outpatient clinic at Kosair Children's Hospital, Louisville, Kentucky, USA.

SUBJECTS

A total of 20 children, 7 girls and 13 boys, with stable asthma but reduced forced expiratory flows between 25% and 75% of vital capacity (FEF(25-75) ) were included in the study.

INTERVENTION

After the initial assessment, each subject was switched from conventional ICS to HFA-BDP. All other medications remained the same. Reassessment of lung function and clinical status was performed at least 3 weeks after the intervention.

RESULTS

FEF(25-75) increased from a mean of 50.75% to 68.85% predicted (P < 0.001). Forced expiratory volume in 1 sec (FEV(1)) also increased significantly from 84.6% to 93.8% predicted (P = 0.001). No changes asthma symptoms were observed.

CONCLUSION

Compared to conventional ICS, the use of HFA-BDP in asthmatic children significantly improves airflow in both the large and the peripheral airways without loss of asthma control.

Prevalence of asthma and bronchial hyperreactivity in Danish schoolchildren: no change over 10 years

AIM

To describe the point prevalence of current physician-diagnosed asthma and bronchial hyperreactivity (BHR) in 2001 among unselected Danish schoolchildren aged 6-17 years, compared with the prevalence from a similar study from 1990 to 1991.

METHODS

Cross-sectional study using parental questionnaire on asthma and respiratory symptoms combined with a 6-min free running test with peak expiratory flow rate (PEFR) measurement (n = 1051, response rate 89.3%). Results were compared with those of a similar study in the same area from 1990 to 1991. Main outcome measures were current physician-diagnosed asthma or BHR in children without physician-diagnosed asthma measured by either a decrease in lung function after standardized running test and/or variability in PEFR on home monitoring.

RESULTS

The prevalence of current physician-diagnosed asthma was 4.0% [95% confidence interval (CI) 2.7-5.3%] in 1990-1991 and 3.6% (95% CI 2.4-4.8%) in 2001. The prevalence of BHR was 3.2% (95% CI 2.0-4.4%) in 1990-1991 and 2.0% (95% CI 1.1-2.9%) in 2001. The combined prevalence was 7.2% (95% CI 5.4-8.9%) in 1990-1991 and 5.6% (95% CI 4.2-7.1%) in 2001.

CONCLUSION

The point prevalence of current physician-diagnosed asthma and BHR among unselected Danish schoolchildren aged 6-17 years was unchanged over 10 years between 1990-1991 and 2001.

[Involvement of distal airways in asthma: lessons from pediatric cohorts]

INTRODUCTION

Prospective studies of paediatric cohorts contribute to our knowledge of changes in pulmonary function in children with asthma.

STATE OF THE ART

Asthma is associated with a significant impairment of the distal airways which is more pronounced when asthma has started early, before 5 years of age, or when asthma is persistent. In utero exposure to tobacco smoke allergenic sensitization and persistent bronchial hyperresponsiveness are the main factors associated with an unfavourable respiratory function outcome. This impairment may persist despite the disappearance of symptoms. Distal airway alterations are also poorly responsive to conventional inhaled corticosteroid therapy. This could be due to early remodelling phenomenon or non-optimal deposition of the drugs on distal airways.

PERSPECTIVES AND CONCLUSIONS

The medium and long term clinical implications of distal airway involvement in paediatric asthma and the impact of treatment need to be evaluated.

Managing asthma in the real world

Asthma treatment is suboptimal in many patients, with impacts on morbidity and mortality, healthcare resource utilisation and patients' quality of life. The reasons for this include the inherent variability of asthma and the unpredictability of exacerbations, which can range from mild to fatal. In addition, asthma can be difficult to diagnose, particularly in the very young and old. Although treatment guidelines are widely available and well publicised, surveys have identified a significant gap between treatment aims and current levels of asthma control. Patient adherence to inhaled corticosteroids is poor, and many patients rely on short-acting beta2-agonists. The reasons for this are complex but are believed to include poor perception by patients of their asthma severity, concerns about the safety and efficacy of medication and low treatment expectations. Patients appear to be unaware of the extent to which airway inflammation can be controlled and are therefore satisfied with poor asthma control, accepting a high level of symptoms. Increasing patient understanding of asthma and its treatment, allowing patients greater involvement in treatment decisions, increasing the role of asthma nurses and improved communication between physicians and patients may improve outcomes in patients with asthma.

Can schoolchildren provide valid answers about their respiratory health experiences in questionnaires? Implications for epidemiological studies

To evaluate the relative validity of information on children's respiratory experience given by different informants, we examined and compared the relationship between low ventilatory function (defined as more than 1 standard deviation below the corresponding mean) and schoolchildren's respiratory symptoms or illnesses reported separately by the children and their parents, using a standard respiratory questionnaire. A total of 1,963 children aged 8-12 years from 12 primary schools in three districts of Hong Kong provided parent-completed and self-completed questionnaires, as well as acceptable spirometric measurements. Prevalence of low forced expiratory volume ratio (FEV1/FVC) and low forced expiratory flow rate between 25-75% of FVC (FEF25-75) were higher among those with either parent or child-reported symptoms/illnesses. Child-reported cough and phlegm performed better than the corresponding parent-reported symptoms in predicting low FEV1/FVC. The contrary was true for wheezing and bronchitis. For low FEF25-75, parent-reported wheezing, asthma, and bronchitis performed better, while the opposite was true for cough. Subgroup analysis by age showed that for older children (age 10 or above), child-reported symptoms/illnesses performed better in general in the prediction of low FEV1/FVC. On the other hand, parent-reported symptoms/illnesses seemed to have an advantage over child-reported ones in predicting low FEF25-75. Subgroup analysis by sex did not reveal any clear pattern. Overall, there was little difference between respiratory illness experiences reported by schoolchildren and their parents in terms of their associations with low ventilatory function. In a population-based study in which schoolchildren are subjects, it would be appropriate for respiratory questionnaires to be administered to the children themselves, especially if they have reached age 10. By doing so, higher response rates, and perhaps also better yields of correct information, may be obtained.

Comparisons of the complementary effect on exhaled nitric oxide of salmeterol vs montelukast in asthmatic children taking regular inhaled budesonide

BACKGROUND

Inhaled, long-acting beta2-agonists or antileukotrienes are alternatives as add-on therapy for asthmatic children taking regular inhaled steroids. Any complementary effects would be relevant to the choice between these alternatives. Exhaled nitric oxide (FeNO) may reflect these effects.

OBJECTIVE

To compare the control of FeNO provided by salmeterol or montelukast add-on therapy in asthmatic children undergoing regular maintenance treatment with a daily dose of 400 microg of budesonide.

METHODS

The study included children with increased FeNO despite regular treatment with budesonide, 400 microg/d, and normal lung function. Montelukast, 5 mg/d, salmeterol, 50 microg twice daily, or placebo was compared as add-on therapy to budesonide, 400 microg, in a randomized, double-blind, double-dummy, crossover study.

RESULTS

Twenty-two children completed the trial. The geometric mean FeNO level was 20 ppb (95% confidence interval [CI], 15-27 ppb) after salmeterol, which was significantly higher than after montelukast (mean, 15 ppb; 95% CI, 11-18 ppb; P = 0.002) and placebo (mean, 15 ppb; 95% CI, 10-21 ppb; P = 0.03). There was no difference in FeNO between the montelukast and placebo groups. Mean forced expiratory volume in 1 second (FEV1) was significantly increased after salmeterol (mean, 2.63 L; 95% CI, 2.34-2.91 L) compared with placebo (mean, 2.48 L; 95% CI, 2.19-2.77 L). Montelukast (mean, 2.57 L; 95% CI, 2.33-2.80 L) was no different than placebo.

CONCLUSIONS

The FeNO levels were significantly higher after salmeterol add-on treatment compared with both placebo and montelukast add-on treatment. Salmeterol significantly improved lung function (FEV1) compared with placebo and nonsignificantly compared with montelukast. Montelukast failed to reduce FeNO and improve lung function compared with placebo in this group of children taking regular budesonide, 400 microg.

Development and validation of a brief pediatric screen for asthma and allergies among children

BACKGROUND

Asthma is the most common disease of childhood, but the recognition and detection remain poor, especially among schoolchildren. There has been an increase in the number of instruments available to detect the risk of asthma earlier in children. We have previously validated a simple, self-reported screen, the Brief Pediatric Asthma Screen (BPAS).

OBJECTIVE

To develop a new screen for asthma and allergies based on the BPAS (BPAS+) with the intent of keeping the screen brief and simple, while including allergy detection.

METHODS

Questions from the BPAS were extensively revised, and questions regarding allergic rhinitis were added. A panel of parents of asthmatic children reviewed and critiqued the questions. The final BPAS + was distributed in elementary schools, and a cohort of 129 participated in a validation against the gold standard of evaluation by an expert in asthma.

RESULTS

For asthma the best items were wheeze, persistent cough, night cough, and response to change in air temperature. The simplest scoring, any 1 of the 4 items, yielded the best balance of specificity (73.6%) and sensitivity (73.3%). For allergy, using all six items, having any one or any two of the items had sensitivity of 71.4% and specificity of 77.3%.

CONCLUSIONS

The BPAS+ provides a rapid and valid method for the detection of potential allergy and asthma in schoolchildren. Sensitivity and specificity are acceptable for both asthma and allergies.

Schoolboys with bronchial asthma in Al-Khobar City, Saudi Arabia: are they at increased risk of school absenteeism?

The objective of this cross-sectional study was to determine the mean period of school absenteeism (MPSA) among asthmatic Saudi schoolboys of Al-Khobar City and to determine the factors associated with the absenteeism. The methodology included the distribution of a self-administered questionnaire, which was completed by the parents of 1482 schoolboys who satisfied the selection criteria of the study. The prevalence rate of questionnaire-diagnosed asthma (QDA) was 9.5% (141/1482). The MPSA among questionnaire-diagnosed asthmatic boys (QDAs) was 13.6 +/- 3.4 days compared to 3.7 +/- 2.2 days among non questionnaire-diagnosed asthmatic boys (non QDAs). Among QDAs, the MPSA was associated significantly and positively with those who were younger, and with decreasing levels of socioeconomic class, histories of pets at home, presence of a currently smoking family member (father or both parents), visit to a hospital emergency room, and admission to hospital. It was significantly and negatively associated with concomitant use of prophylactic medication(s), including those used appropriately. The QDAs from middle and lower socioeconomic classes showed less use of prophylactic medication(s) but more histories of visits to an emergency room and of admissions to hospital. The multiple linear regression equation for the total period of school absenteeism (TPSA) during the 1995 academic year was generated. Asthmatic school children have a higher MPSA compared to their non asthmatic classmates. The risk of suffering the impacts of this disease is shown to be particularly increased among QDAs belonging to less socioeconomically advantaged families.

Prescribing patterns for asthma by general practitioners in six European countries

To assess the level of concordance with international consensus on asthma management, we compared primary care prescribing patterns for asthma in different European countries. A prospective study of prescription items with an associated diagnostic label of asthma in patient consultations with a total of 235 general practitioners (GPs) from Belgium, England, Ireland, Italy, Northern Ireland, Portugal, Scotland and Spain was performed. A total of 101,544 consecutive consultations were recorded in autumns 1994 and 1995 of which 3595 (3.5%) were for patients with asthma and 3243 (3.2%) were for patients receiving a prescription for asthma. Overall, asthma consultations varied from 1.8% in Italy to 5.8% in Ireland (mean 3.4%, SD 1.6). Prescribed inhaled medications for children varied from 72% of the total asthma prescriptions in Ireland and Portugal to 82% in Northern Ireland (mean 79%, SD 8.1) and for adults 55% in Italy to 85% in Spain (mean 70%, SD 10). Inhaled corticosteroid usage for adults varied from 14% in Italy to 31% in Northern Ireland (mean 24%, SD 6.4). For children, beta2-agonist use varied from 24% in Italy to 67% in Spain (mean 45%, SD 13). Despite publication of international guidelines for the management of asthma, inter-country prescribing practices vary considerably and could be improved. The frequency of use of asthma as a diagnostic label also varies markedly.

Validation of the Brief Pediatric Asthma Screen

STUDY OBJECTIVES

The purpose of this study was to confirm the validity of a brief screen for pediatric asthma in schools.

BACKGROUND

Asthma is the most common chronic disease of childhood, yet the frequency with which this condition is recognized among school-aged children varies widely. Several methods are used to increase the accuracy of detection of asthma, but many are cumbersome and difficult to apply on a large scale.

DESIGN

We elected to validate a five-question instrument, the Brief Pediatric Asthma Screen (BPAS), to screen for the presence of asthma among children attending school in Region 5 of the Chicago school district, where the schools report a 2.7% frequency of asthma. The questionnaire was distributed to the parents of grade-school children at the time of report-card pick-up.

SETTING

A clinical assessment was performed on a selected group of children whose parents completed the questionnaire in a school and in a hospital outpatient clinic.

PARTICIPANTS

Of 4,147 questionnaires that we distributed, 1,796 (43%) were returned. We excluded 341 children (19% of the total sample) whose parents reported that they had been diagnosed with asthma. The remaining pool indicated that the children of 183 responders (10%) had symptoms suggestive of asthma, while 1,272 parents (71%) indicated that their children did not have symptoms of asthma.

MEASUREMENTS AND RESULTS

We selected 90 of the respondents who did not indicate that their children had a diagnosis of asthma. Of this group, 81 completed the validation, in which their responses suggested symptoms of asthma (n = 34) or no asthma symptoms (n = 47). The children of these respondents were given a blinded clinical evaluation consisting of history, physical examination, and spirometry. The survey demonstrated a sensitivity of 75% and a specificity of 81.2% for the presence of asthma among those who were unaware of the diagnosis.

CONCLUSIONS

The BPAS is brief, can be filled out by parents, and appears accurate in detecting asthma.