How accurate is the diagnosis of exercise induced asthma among Vancouver schoolchildren?

A systematic review of the literature on screening for exercise-induced asthma: considerations for school nurses

Asthma is a major cause of illness, missed school days, and hospitalization in children. One type of asthma common in children is exercise-induced asthma (EIA). EIA causes airway narrowing with symptoms of cough and shortness of breath during exercise. The purpose of this article is to review the literature relevant to screening children and adolescents for EIA and to inform development of a school nurse-led EIA screening program. A systematic review of EIA screening tests was conducted by searching PUBMED for key terms. Sixty-seven articles were identified; after review only seven met the inclusion criteria. The most common screening test was the 6-min exercise challenge. School-based screening programs have the potential to identify EIA among undiagnosed children and adolescents. School nurses are health professionals with the knowledge and skills necessary to develop successful screening programs in the school setting. Based on results of the literature review, we present implications for developing screening programs in schools to identify children with undiagnosed EIA.

Improving screening and diagnosis of exercise-induced bronchoconstriction: a call to action

This article summarizes the findings of an expert panel of nationally recognized allergists and pulmonologists who met to discuss how to improve detection and diagnosis of exercise-induced bronchoconstriction (EIB), a transient airway narrowing that occurs during and most often after exercise in people with and without underlying asthma. EIB is both commonly underdiagnosed and overdiagnosed. EIB underdiagnosis may result in habitual avoidance of sports and physical activity, chronic deconditioning, weight gain, poor asthma control, low self-esteem, and reduced quality of life. Routine use of a reliable and valid self-administered EIB screening questionnaire by professionals best positioned to screen large numbers of people could substantially improve the detection of EIB. The authors conducted a systematic review of the literature that evaluated the accuracy of EIB screening questionnaires that might be adopted for widespread EIB screening in the general population. Results of this review indicated that no existing EIB screening questionnaire had adequate sensitivity and specificity for this purpose. The authors present a call to action to develop a new EIB screening questionnaire, and discuss the rigorous qualitative and quantitative research necessary to develop and validate such an instrument, including key methodological pitfalls that must be avoided.

Paradoxical vocal fold motion disorder in the elite athlete: experience at a large division I university

OBJECTIVES/HYPOTHESIS

To review our experience at a large division I university with the diagnosis and management of paradoxical vocal fold motion disorder (PVFMD) in elite athletes.

STUDY DESIGN

A single institution retrospective review and cohort analysis.

METHODS

All elite athletes (division I collegiate athletes, triathletes, and marathon runners) with a diagnosis of PVFMD were identified. All patients underwent flexible fiberoptic laryngoscopy (FFL) to confirm the diagnosis of PVFMD. The type of PVFMD therapy was identified and efficacy of treatment was graded based on symptom resolution.

RESULTS

Forty-six consecutive athletes with PVFMD were identified. A total of 30/46 (65%) were division 1 collegiate athletes and 16/46 (35%) were triathletes or marathon runners. In comparison to a nonathlete PVFMD cohort, athletes were less likely to present with a history of reflux (P < 0.01), psychiatric diagnosis (P < 0.01), dysphonia (P < 0.01), cough (P = 0.02), or dysphagia (P < 0.01). The use of postexertion FFL provided additional diagnostic information in 11 (24%) patients. Laryngeal control therapy (LCT) was recommended for 45/46. A total of 36/45 attended at least one LCT session and 25 (69%) reported improvement of symptoms. Additionally, biofeedback, practice-observed therapy, and thyroarytenoid muscle botulinum toxin injection were required in three, two, and two patients, respectively.

CONCLUSION

The addition of postexertion FFL improves the sensitivity to detect PVFMD in athletes. PVFMD in athletes responds well to LCT. However, biofeedback, practice-observed therapy, and botulinum toxin injection may be required for those patients with an inadequate response to therapy.

LEVEL OF EVIDENCE

4.

Paradoxic vocal fold movement disorder

Paradoxical Vocal Fold Movement Disorder (PVFMD) is a cause of dyspnea that can mimic or occur alongside asthma or other pulmonary disease. Treatment with Laryngeal Control Therapy is very effective once the entity is properly diagnosed and contributing comorbidities are managed appropriately. In understanding the etiology of PVFMD, focus has broadened beyond psychiatric factors alone to include the spectrum of laryngeal irritants (laryngopharyngeal reflux, allergic and sinus disease, sicca, and possibly obstructive sleep apnea). The following is a discussion of the history, terminology, epidemiology, diagnosis, comorbid conditions, and treatment of this entity.

Exercise-induced bronchoconstriction and vocal cord dysfunction: two sides of the same coin?

Patients are referred often because of self-reported symptoms of dyspnea and wheeze during exercise. The two common causes of exercise-induced dyspnea are exercise-induced bronchoconstriction (EIB) and vocal cord dysfunction (VCD). It can be extraordinarily difficult to differentiate between the two, especially because they may coexist in the same patient. EIB is caused by bronchial smooth muscle constriction in the lower airways due to the inhalation of dry air or allergens during exercise; it is associated with the release of bronchoconstricting mediators from airway cells. EIB can occur in patients with or without persistent asthma. In contrast, VCD is associated with the paradoxical adduction of the vocal cords, especially during inhalation, which may produce inspiratory stridor. VCD can be solitary or comorbid with asthma and/or EIB. EIB classically is most severe after the cessation of exercise, while VCD typically occurs during exercise and resolves quickly upon exercise cessation. However, history is not adequate to differentiate between EIB and VCD, and appropriate challenge tests and flexible laryngoscopy during exercise are often necessary for diagnosis. This article examines our current understanding of these entities and discusses the mechanism, prevalence, diagnosis, and treatment.

Contemporary topics in pediatric pulmonology for the primary care clinician

Disorders of the respiratory system are commonly encountered in the primary care setting. The presentations are myriad and this review will discuss some of the more intriguing or vexing disorders that the clinician must evaluate and treat. Among these are dyspnea, chronic cough, chest pain, wheezing, and asthma. Dyspnea and chest pain have a spectrum ranging from benign to serious, and the ability to effectively form a differential diagnosis is critical for reassurance and treatment, along with decisions on when to refer for specialist evaluation. Chronic cough is one of the more common reasons for primary care office visits, and once again, a proper differential diagnosis is necessary to assist the clinician in formulating an appropriate treatment plan. Infant wheezing creates much anxiety for parents and accounts for a large number of office visits and hospital admissions. Common diagnoses and evaluation strategies of early childhood wheezing are reviewed. Asthma is one of the most common chronic diseases of children and adults. The epidemiology, diagnosis, evaluation, treatment, and the patient/parent education process will be reviewed. A relatively new topic for primary care clinicians is cystic fibrosis newborn screening. The rationale, methods, outcomes, and implications will be reviewed. This screening program may present some challenges for clinicians caring for newborns, and an understanding of the screening process will help the clinician communicate effectively with parents of the patient.

Exercise-related respiratory symptoms and exercise-induced bronchoconstriction in industrial bakers

In order to assess prevalence and characteristics of exercise-related respiratory symptoms (ERRS) and exercise-induced bronchoconstriction (EIB) in industrial bakery, the authors performed a cross-sectional study including 57 bakers and an equal number of office workers studied as a control. Evaluation of examined subjects included completion of a questionnaire, skin prick tests to common inhalant and occupational allergens, spirometry, and exercise and histamine challenge. The authors found a similar prevalence of ERRS and EIB in both bakers and controls. EIB was significantly associated with atopy, asthma, family history of asthma, and positive histamine challenge in either group, whereas in bakers it was closely related to sensitization to occupational allergens (p = .032). Bronchial reaction to exercise was significantly higher in bakers with EIB (25.7% vs 19.2%; p = .021). These findings suggest that occupational exposure in industrial bakery may accentuate bronchoconstrictive response to exercise.

Vocal cord dysfunction

Vocal cord dysfunction (VCD), generally characterized by paradoxical closure of the vocal cords during inspiration, is a common mimicker of asthma and of other conditions that cause upper airway obstruction. As a result, it is frequently overlooked and often misdiagnosed, resulting in administration of excessive medications or other unnecessary interventions, with resultant morbidity. This article explores the clinical features, proposed causes, diagnostic considerations, and management of VCD, as well as some differences between VCD and asthma that can aid in differentiating these two diagnoses in the clinical setting.

Childhood asthma: diagnosis and treatment

Many children suffer from recurrent coughing, wheezing and chest tightness. In preschool children one third of all children have these symptoms before the age of six, but only 40% of these wheezing preschoolers will continue to have asthma. In older school-aged children the majority of the children have asthma. Quality of life is affected by asthma control. Sleep disruption and exercised induced airflow limitation have a negative impact on participation in sports and social activities, and may influence family life. The goal of asthma therapy is to achieve asthma control, but only a limited number of patients are able to reach total control. This may be due to an incorrect diagnosis, co-morbidities or poor inhalation technique, but in the majority of cases non-adherence is the main reason for therapy failures. However, partnership with the parents and the child is important in order to set individually chosen goals of therapy and may be of help to improve control. Non-pharmacological measures aim at avoiding tobacco smoke, and when a child is sensitised, to avoid allergens. In pharmacological management international guidelines such as the GINA guideline and the British Guideline on the Management of Asthma are leading.

The Saudi initiative for asthma - 2012 update: Guidelines for the diagnosis and management of asthma in adults and children

This an updated guidelines for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of SINA is to have updated guidelines, which are simple to understand and easy to use by non-asthma specialists, including primary care and general practice physicians. This new version includes updates of acute and chronic asthma management, with more emphasis on the use of Asthma Control Test in the management of asthma, and a new section on "difficult-to-treat asthma." Further, the section on asthma in children was re-written to cover different aspects in this age group. The SINA panel is a group of Saudi experts with well-respected academic backgrounds and experience in the field of asthma. The guidelines are formatted based on the available evidence, local literature, and the current situation in Saudi Arabia. There was an emphasis on patient-doctor partnership in the management that also includes a self-management plan. The approach adopted by the SINA group is mainly based on disease control as it is the ultimate goal of treatment.

Inspiratory airflow limitation after exercise challenge in cold air in asthmatic children

Methacholine and histamine can lead to inspiratory flow limitation in asthmatic children and adults. This has not been analyzed after indirect airway stimuli, such as exercise. The aim of the study was to analyze airflow limitation after exercise in cold, dry air. 72 asthmatic children with mild to moderate asthma (mean age 13.2 ± 2.2 yrs) performed a treadmill exercise challenge. A fall of >10% in FEV(1) was the threshold for expiratory flow limitation and a fall of >25% of MIF(50) was the threshold for inspiratory flow limitation. The occurrence of wheeze, stridor and cough were quantified before and after exercise. After exercise, the mean fall in FEV(1) was 17.7 ± 14.6%, while the mean fall in MIF(50) was 25.4 ± 15.8%; no correlation was found between fall in FEV(1) and MIF(50) (R(2): 0.04; p = 0.717). 53 of the 72 children showed an inspiratory and/or expiratory airflow limitation. 38% (20/53) of these children showed an isolated expiratory flow limitation, 45% (24/53) showed both expiratory and inspiratory flow limitation and 17% (9/53) showed an isolated inspiratory flow limitation. The fall in FEV(1) peaked 9 min after exercise and correlated to expiratory wheeze. The fall in MIF(50) peaked 15 min after exercise and correlated to inspiratory stridor. The time difference in peak fall between FEV(1) and MIF(50) was statistically significant (5.9 min; p < 0.001, 99% CI: 2.3-9.5 min). In conclusion, this study shows that an exercise challenge in asthmatic children can give rise to inspiratory airflow limitation, which may give rise to asthma like symptoms.

Etiology of dyspnea in elite and recreational athletes

BACKGROUND

Breathing complaints are common in athletes. Studies have suggested that the prevalence of asthma and exercise-induced bronchoconstriction (EIB) is higher in elite athletes than the general population. Vocal cord dysfunction (VCD) may mimic asthma and EIB as a cause of dyspnea in athletes. However, the majority of studies to date have primarily relied on symptoms to diagnose VCD, and there are limited data on coexistence of asthma, EIB, and/or VCD. It is well established that symptoms alone are inadequate to accurately diagnose EIB and VCD. Our goal was to define via objective testing the prevalence of asthma, EIB, VCD alone, or in combination in a cohort of athletes with respiratory complaints.

METHODS

A retrospective chart review was done of 148 consecutive athletes (collegiate, middle school, high school, and recreational) referred to a tertiary care center's asthma center for evaluation of respiratory complaints with exercise. An evaluation including medical history, physical examination, and objective testing including pulmonary function testing (PFT), eucapnic voluntary hyperventilation, and video laryngostroboscopy, were performed.

RESULTS

The most common symptom was dyspnea on exertion (96%), with < 1% complaining of either hoarseness or stridor. The most common diagnosis prior to referral was asthma (40%). Only 16% had PFTs prior to referral. Following evaluation by a pulmonologist, 52% were diagnosed with EIB, 17% with asthma, and 70% with VCD. Of those diagnosed with asthma before our evaluation, the diagnosis of asthma was confirmed, with PFTs in only 19 of 59 (32%) athletes based on our testing. Vocal cord dysfunction was more common in females and in adolescent athletes. Coexistence of multiple disorders was common, such as EIB and asthma (8%), EIB and VCD (31%), and VCD and asthma (6%).

CONCLUSIONS

Asthma and EIB are common etiologies of dyspnea in athletes, both competitive and recreational. However, VCD is also common and can coexist with either asthma or EIB. Vocal cord dysfunction may contribute to exercise-related respiratory symptoms more frequently in middle school- and high school-aged athletes than in college athletes. Effective treatment of dyspnea requires appropriate identification and treatment of all disorders. Classic symptoms of stridor and/or hoarseness are often not present in athletes with VCD. Accurate diagnosis of asthma, EIB, and VCD requires objective testing and can prevent exposure of patients to medications that are ineffective and have potential adverse side effects. Furthermore, there is need for increased awareness of VCD as a common cause of respiratory complaints in athletes, either as a single diagnosis or in combination with EIB, especially in females, as well as middle school and high school athletes.

Fifty years of pediatric asthma in developed countries: how reliable are the basic data sources?

Given the difficulties in diagnosing, or even defining, asthma in children, claims of a pediatric asthma epidemic in Canada and other developed countries are accepted with surprisingly little critical examination. We reviewed a broad range of data sources to understand how the epidemic evolved during the last 50 years and also to assess the reliability of the conclusions drawn from that data. We obtained Canadian National and Provincial data from Statistics Canada National Population Health Survey, and the British Columbia Ministry of Health respiratory database. International data were obtained by extensive review of pediatric asthma epidemiological surveys published during the last 50 years. In many developed countries, there have been three separate epidemics involving different aspects of pediatric asthma during the last 50 years: a double peaked mortality epidemic (1960s and 1980s), a hospital admission epidemic (peaked around 1990) and a steadily growing epidemic of children who report asthmatic symptoms on questionnaires. Canadian pediatric rates for asthma mortality (1-2/million/year) and hospital admission (1-2/thousand/year) are low and have fallen for the last 20 years. Rates based on questionnaire studies are high (10-15/hundred) and rose steadily over the same period. Objective reductions in asthma deaths and hospital admission likely reflect improved education and treatment programmes. Current claims of an epidemic based largely on subjective self-reported symptoms require more careful analysis. The possibility that symptom misperception, disease fashions, and poor recall, may be part of the explanation for the current high levels of self-reported symptoms deserves more attention.

Evaluation of association between exercise-induced bronchoconstriction and childhood asthma control test questionnaire scores in children

OBJECTIVE

Asthma control represents a major challenge in the management of asthmatic children; however, correct perception of control is poor. The aim of the study was to evaluate the association between subjective answers given to the Childhood Asthma Control Test (C-ACT) and objective evaluation of exercise-induced bronchonstriction (EIB) by standardized treadmill exercise challenge.

METHODS

EIB was evaluated by standardized treadmill exercise challenge and related to C-ACT scores in 92 asthmatic children.

RESULTS

Of the 92 studied children only six children had a concordance between a positive challenge test (ΔFEV1 ≥ 13%) and a positive response to the exercise-related issue of the C-ACT questionnaire (C-ACT total score ≤ 19). There was no significant association between the degree of EIB and the scores relative to the single question on exercise-related problems while a significant association was found when considering the whole questionnaire with C-ACT total score > 19 (r = -0.40, P < 0.001). The two single questions showing a significant association were those focusing on nocturnal asthma. The areas under the ROC curve (AUC) for the sum of the scores of these questions in relationship to a positive response to the exercise test was 0.74. The AUC of the C-ACT total score was 0.76 and 0.55 for the specific question on EIB related problems.

CONCLUSION

The discrimination power of the C-ACT total score in relationship to EIB was moderately good, and C-ACT questionnaire was capable of correctly predicting the absence of EIB in children reporting a global score > 19. However, direct questions on EIB are associated with a high number of false positive and negative responses; better associations are found questioning on the presence on nocturnal symptoms.

Asthma in elite athletes: pathogenesis, diagnosis, differential diagnoses, and treatment

Elite athletes have a high prevalence of asthma and exercise-induced bronchoconstriction. Although respiratory symptoms can be suggestive of asthma, the diagnosis of asthma in elite athletes cannot be based solely on the presence or absence of symptoms; diagnosis should be based on objective measurements, such as the eucapnic voluntary hyperpnea test or exercise test. When considering that not all respiratory symptoms are due to asthma, other diagnoses should be considered. Certain regulations apply to elite athletes who require asthma medication for asthma. Knowledge of these regulations is essential when treating elite athletes. This article is aimed at physicians who diagnose and treat athletes with respiratory symptoms. It focuses on the pathogenesis of asthma and exercise-induced bronchoconstriction in elite athletes and how the diagnosis can be made. Furthermore, treatment of elite athletes with asthma, anti-doping regulations, and differential diagnoses such as exercise-induced laryngomalacia are discussed.

Physical activity recommendations for children with specific chronic health conditions: Juvenile idiopathic arthritis, hemophilia, asthma and cystic fibrosis

As a group, children with a chronic disease or disability are less active than their healthy peers. There are many reasons for suboptimal physical activity, including biological, psychological and social factors. Furthermore, the lack of specific guidelines for 'safe' physical activity participation poses a barrier to increasing activity. Physical activity provides significant general health benefits and may improve disease outcomes. Each child with a chronic illness should be evaluated by an experienced physician for activity counselling and for identifing any contraindications to participation. The present statement reviews the benefits and risks of participation in sport and exercise for children with juvenile arthritis, hemophilia, asthma and cystic fibrosis. Guidelines for participation are included.

Exercise-Induced Lung Disease: Too Much of a Good Thing?

Exercise in children has important health benefits. However, in elite endurance athletes, there is an increased prevalence of exercise-induced bronchoconstriction and airway inflammation. Particularly at risk are those who practice in cold weather, ice rinks, swimming pools, and air pollution. The inflammation is caused by repetitive episodes of hyperventilation of cold, dry air, allergens, or toxins such as chlorine or air pollution. Children may be particularly at risk for lung injury under these conditions because of the immaturity and ongoing development of their lung. However, studies in pediatric athletes and exercising young children are sparse. Epithelial injury associated with hyperventilation of cold, dry air has not been described in children. However, exercise in the presence of air pollution and chlorine is associated with airway injury and the development of asthma in children; the effect appears to be modulated by both atopy and genetic polymorphisms. While management of exercise-induced bronchoconstriction and asthma is well established, there is little data to guide treatment or prevention of remodeling in athletes or inhalational lung injury in children. Studies underscore the need to maintain high levels of air quality. More investigations should be undertaken to better define the natural history, pathophysiology, and treatment of exercise-induced pulmonary inflammation in both elite athletes and exercising children.

Exercise-induced laryngeal obstructions: prevalence and symptoms in the general public

Respiratory difficulties caused by exercise-induced laryngeal obstructions (EILOs) are reported with increasing frequency. The aim of this study was to assess the prevalence and symptoms of EILOs and their relation to airway hyperresponsiveness (AHR). In total, 556 randomly selected youths in Copenhagen aged 14-24 years were invited over a 2-year period. The study included a mailed questionnaire and two visits: day 1 (an interview-based questionnaire, methacholine bronchial provocation test and physical exertion test); and day 2 [an exercise test with continuous laryngoscopic recordings (CLE test)]. The diagnosis of EILOs was based on the CLE test. In total, 237 answered the mailed questionnaire and 150 participated on day 1 whereof 98 participated on day 2 also. AHR was verified in 23 (4.1% of invitees) and EILOs in 42 (7.5% of invitees). Co-morbidity was verified in 6 cases (26.1% of verified AHR cases). No symptoms were found specific for either AHR or EILOs. The minimum prevalence of EILOs in this cohort was 7.5%. EILOs were verified in 26.1% of participants with AHR. Questionnaires could not differentiate between AHR and EILOs.

Breathing abnormalities in children with breathlessness

Dysfunctional breathing, hyperventilation and vocal cord dysfunction are frequently seen in children and adults. The prevalence is unknown. There are no standardized diagnostic criteria, and for now, effective exclusion of organic disease leaves the diagnosis of dysfunctional breathing. Therapy is mainly focussed on explanation of a benign condition and reassurance. Since dysfunctional breathing is a possible chronic condition, other therapies should be evaluated. In adults physiotherapy and breathing retraining appear beneficial. In childhood there is lack of evidence, and further research is necessary in order to optimise the outcome for children with dysfunctional breathing.

Association of the asthma control questionnaire with exercise-induced bronchoconstriction

INTRODUCTION

Asthma is a common chronic disease in childhood which features bronchial hyperresponsiveness to exercise (EIB). In daily clinical practice, the report of EIB is used to assess the level of control of asthma. The asthma control questionnaire (ACQ) is a tool to evaluate the control of asthma in children. The aim of this study was to evaluate the relationship between the ACQ and EIB.

MATERIALS AND METHODS

Two hundred children, aged 12.5 ± 2.5 years, with a pediatrician-diagnosed mild-to-moderate asthma filled out an ACQ and performed an exercise provocation test in cold air. EIB was defined as a fall in FEV(1) of 15%.

RESULTS

Eighty six of the 200 children had a positive exercise challenge. There was no relationship between the categorical ACQ and the occurrence of EIB (p = .39). There was no difference in the occurrence of EIB between genders (p = .12). The positive predictive value of the ACQ for EIB was 51% and the negative predictive value for EIB was 59%. In comparison to the girls, the boys carried an odds ratio (OR) of 0.48 for having an indifferent control of asthma (p = .04; confidence interval (CI): 0.23-0.96), and an OR of 0.46 for having a not well-controlled asthma (p = .03; CI: 0.23-0.93).

CONCLUSION

This study shows that the ACQ is not related to EIB in children with asthma. Remarkable is the percentage (41%) of children who, despite well-controlled asthma according to the ACQ, had EIB, which implies that their asthma is not well-controlled. Boys were more likely to report well-controlled asthma, although boys and girls were equally likely to have EIB.

Management of severe asthma in children

Children who are referred to specialist care with asthma that does not respond to treatment (problematic severe asthma) are a heterogeneous group, with substantial morbidity. The evidence base for management is sparse, and is mostly based on data from studies in children with mild and moderate asthma and on extrapolation of data from studies in adults with severe asthma. In many children with severe asthma, the diagnosis is wrong or adherence to treatment is poor. The first step is a detailed diagnostic assessment to exclude an alternative diagnosis ("not asthma at all"), followed by a multidisciplinary approach to exclude comorbidities ("asthma plus") and to assess whether the child has difficult asthma (improves when the basic management needs, such as adherence and inhaler technique, are corrected) or true, therapy-resistant asthma (still symptomatic even when the basic management needs are resolved). In particular, environmental causes of secondary steroid resistance should be identified. An individualised treatment plan should be devised depending on the clinical and pathophysiological characterisation. Licensed therapeutic approaches include high-dose inhaled steroids, the Symbicort maintenance and reliever (SMART) regimen (with budesonide and formoterol fumarate), and anti-IgE therapy. Unlicensed treatments include methotrexate, azathioprine, ciclosporin, and subcutaneous terbutaline infusions. Paediatric data are needed on cytokine-specific monoclonal antibody therapies and bronchial thermoplasty. However, despite the interest in innovative approaches, getting the basics right in children with apparently severe asthma will remain the foundation of management for the foreseeable future.

Vocal cord dysfunction, paradoxic vocal fold motion, or laryngomalacia? Our understanding requires an interdisciplinary approach

This article presents disorders of periodic occurrence of laryngeal obstruction (POLO) resulting in noisy breathing and dyspnea and a variety of secondary symptoms. Included in this classification are glottic disorders, such as paradoxic vocal fold movement and vocal cord dysfunction. The supraglottic disorder, termed, intermittent arytenoid region prolapse or laryngomalacia, is also reviewed. Three categories of POLO are defined as irritant, exertional, and psychological.

Physical activity recommendations for children with specific chronic health conditions: juvenile idiopathic arthritis, hemophilia, asthma, and cystic fibrosis

As a group, children with a chronic disease or disability are less active than their healthy peers. There are many reasons for suboptimal physical activity, including biological, psychological, and social factors. Furthermore, the lack of specific guidelines for 'safe' physical activity participation poses a barrier to increasing activity. Physical activity provides significant general health benefits and may improve disease outcomes. Each child with a chronic illness should be evaluated by an experienced physician for activity counselling and for identifying any contraindications to participation. The present statement reviews the benefits and risks of participation in sport and exercise for children with juvenile arthritis, hemophilia, asthma, and cystic fibrosis. Guidelines for participation are included.

Imitators of exercise-induced bronchoconstriction

Exercise-induced bronchoconstriction (EIB) is described by transient narrowing of the airways after exercise. It occurs in approximately 10% of the general population, while athletes may show a higher prevalence, especially in cold weather and ice rink athletes. Diagnosis of EIB is often made on the basis of self-reported symptoms without objective lung function tests, however, the presence of EIB can not be accurately determined on the basis of symptoms and may be under-, over-, or misdiagnosed. The goal of this review is to describe other clinical entities that mimic asthma or EIB symptoms and can be confused with EIB.

The relation between age and time to maximal bronchoconstriction following exercise in children

BACKGROUND

The exercise challenge test (ECT) is a common tool for assessment of asthma in children. Many studies suggest that the "time to maximal bronchoconstriction" (Nadir-t) after exercise challenge in asthmatic children may be age-dependent, although this has never been systematically studied. Such findings may influence epidemiological surveys where the schedule of post-exercise measurements is trimmed. This study systematically assesses the relation between age and time to maximal bronchoconstriction post-ECT.

METHODS

Data were collected retrospectively from 131 subjects (87 male; 3-18 years) who were referred for ECT. The routine ECT was performed according to ATS recommendation of a 6-min run. Spirometry was measured at 1, 3, 5, 10, 15, and 20 min post-exercise. The post-exercise nadir of FEV1 (%baseline) (FEV1-nadir) and the time to maximal fall in Nadir-t (minutes) were sought and values were related to age.

RESULTS

Baseline FEV1 values (mean+/-SD) were 90.5+/-13.8% predicted. FEV1-nadir was -23.6+/-11.7% from baseline values. The Nadir-t was reached at 5.1+/-2.6 min (range 2-12 min). A positive correlation between children's age and Nadir-t was observed (r2=0.542; SD of residuals=1.79; p<0.001), regardless of FEV1-nadir, whether the cutoff of point was -10% or -15% of baseline FEV1. Children <10 years of age showed Nadir-t at 3.4+/-1.7 min post-exercise and older children at 6.6+/-2.5 min post-exercise (p<0.0001).

CONCLUSION

Our results indicate that the time to maximal bronchoconstriction is age-dependent in children and adolescents, and imply that the schedule of post-exercise FEV(1) measurements should be cautiously trimmed.

Exercise-induced bronchospasm among athletes in Lower Silesia Province

A few studies have reported data on the prevalence of exercise-induced bronchospasm in high school and university athletes. Recently published data suggest that exercise-induced bronchospasm may affect up to 39% of American university athletes. To date, no data describing this pathology in athletes from Central Europe have been published. The aim of the present study was to establish the prevalence of exercise-induced bronchospasm in pupils attending sports mastership classes in secondary school as well as students of the University of Physical Education in Wroclaw. The participants were 77 athletes (30 women and 47 men) aged 16-27 years (mean 17.3 years). Only one athlete (1.29%) diagnosed with atopic asthma before testing experienced a fall in forced expiratory volume in one second (12.9% FEV(1)) compared with baseline, which showed that the exercise test result was positive. From a clinical point of view, the ventilation disturbance was asymptomatic. In the other participants, there were slight but statistically significant rises in FEV(1) (P < 0.02). The results of our study indicate a very low prevalence of exercise-induced bronchospasm in the population of athletes examined.

Perceptions and pathophysiology of dyspnea and exercise intolerance

Dyspnea is a complex psychophysiologic sensation that requires intact afferent and efferent pathways for the full perception of the neuromechanical dissociation between the respiratory effort attempted and the work actually accomplished. The sensation is triggered or accentuated by a variety of receptors located in the chest wall, respiratory muscles, lung parenchyma, carotid body, and brain stem. The sensation of dyspnea is stronger in patients with higher scores for anxiety and has been reported in patients with anxiety disorders with no cardiopulmonary disease. These observations demonstrate the importance of cerebral cognition in this complex symptom. Ten cases are presented that illustrate different clinical manifestations of dyspnea.

Dyspnoea in children. Does development alter the perception of breathlessness?

Dyspnoea, the perception of an unpleasant and/or uncomfortable sensation of breathlessness, offers several physiological, anatomical and teleological analogies with pain. Pain perception has been shown to exist in the newborn, suggesting that dyspnoea may also occur from birth onwards. The perception of breathlessness will be subservient to developmental changes in the behaviour of sensors and lung and muscular receptors implicated in dyspnoea, some of which are known to be active at time of birth. For example, perinatal resetting of the arterial chemoreceptor could lead to transient depression of the dyspnoeic response to hypoxia. However, though early evoked ventilatory responses and peripheral receptor maturation do exist, dyspnoea will only occur if the corresponding central neural circuitry undergoes parallel maturation. Our knowledge of dyspnoea in later childhood is based on a small number of clinical or psychophysical studies, predominantly dealing with asthma and exercise. There is a thus a clear need for systematic assessment of the existence and severity of dyspnoea sensing in younger children that takes into account its role as an alarm mechanism for triggering adaptive and/or protective responses.

Dyspnea from exercise in cold air is not always asthma

In the absence of other explanations, exercise-induced dyspnea is often labeled as a manifestation of asthma. The aim of this study was to use exercise provocation in cold air among patients with exercise-induced dyspnea, but without any bronchoconstriction, in order to study induced symptoms and different physiological parameters and to measure the possible influence of exercise in cold air on capsaicin cough sensitivity. Eleven patients with exercise-induced dyspnea but no asthma, along with 11 healthy controls, performed a capsaicin inhalation provocation on two occasions. One of these provocations was preceded by an exercise provocation in a cold chamber. Number of coughs, airway symptoms, spirometry, respiratory rate, pulse rate, end-tidal CO(2), and PSaO(2) were registered. During exercise, the patients coughed more than the controls and also had more airway symptoms. After exercise provocation, spirometry values remained unchanged, but capsaicin cough sensitivity was increased and end-tidal CO(2) decreased among the patients, both in comparison to the controls and in comparison to the patients themselves prior to exercise. Exercise-induced dyspnea may be associated with hypocapnia from hyperventilation and increased capsaicin cough sensitivity. The diagnosis of exercise-induced asthma should be questioned when the patient has no signs of bronchoconstriction.

Pediatric asthma and related allergic and nonallergic diseases: patient-oriented evidence-based essentials that matter

Asthma is the most common medical diagnosis among hospitalized children. In the USA, asthma has accounted for approximately 15% of nonsurgical admissions to hospital in the pediatric age group. Asthma is also one of the leading causes for emergency care requirements, one of the leading causes for missed school, and a cause for considerable morbidity, disability and occasional mortality at all ages. Despite these discouraging statistics, convincing data indicate that this failure of asthma management is not the result of inadequate therapeutic potential, but instead represents ineffective delivery of medical care. Management of asthma and its major co-morbidities, allergic and nonallergic rhinitis, and atopic dermatitis requires a knowledge of the alternative therapies, natural history, and educational techniques for providing patients and families with the ability to manage these troublesome chronic disorders.

Exercise-induced bronchospasm in children

This review will encompass definition, history, epidemiology, pathogenesis, diagnosis, and management of exercise -induced bronchospasm in the pediatric individual with and without known asthma. Exercise induced asthma is the conventional term for transient airway narrowing in a known asthma in association with strenuous exercise usually lasting 5-10 minutes with a decline in pulmonary function by at least 10%. Exercise induced asthma will be referred to as exercise induced bronchospasm in an asthmatic. Exercise-induced bronchospasm (EIB ) is the same phenomenon in an individual without known asthma. EIB can be seen in healthy individuals including children as well as defense recruits and competitive or elite athletes. The diagnosis with objective exercise challenge methods in conjunction with history is delineated. Management is characterized with pharmacotherapy and non pharmacotherapeutic measures for underlying asthma as well as exercise induced bronchospasm and inhalant allergy. Children can successfully participate in all sports if asthma is properly managed.

Paradoxical vocal cord motion disorder: past, present and future

Paradoxical vocal cord motion disorder (PVCM), also called vocal cord dysfunction, is an important differential diagnosis for asthma. The disorder is often misdiagnosed as asthma leading to unnecessary drug use, very high medical utilisation and occasionally tracheal intubation or tracheostomy. Laryngoscopy is the gold standard for diagnosis of PVCM. Speech therapy and psychotherapy are considered the cornerstone of management of this disorder. The aim of this article is to increase the awareness of PVCM among doctors, highlighting the main characteristics that distinguish it from asthma and discuss the recent medical achievements and the possible future perspectives related to this disorder.

Pseudo-asthma: when cough, wheezing, and dyspnea are not asthma

Although asthma is the most common cause of cough, wheeze, and dyspnea in children and adults, asthma is often attributed inappropriately to symptoms from other causes. Cough that is misdiagnosed as asthma can occur with pertussis, cystic fibrosis, primary ciliary dyskinesia, airway abnormalities such as tracheomalacia and bronchomalacia, chronic purulent or suppurative bronchitis in young children, and habit-cough syndrome. The respiratory sounds that occur with the upper airway obstruction caused by the various manifestations of the vocal cord dysfunction syndrome or the less common exercise-induced laryngomalacia are often mischaracterized as wheezing and attributed to asthma. The perception of dyspnea is a prominent symptom of hyperventilation attacks. This can occur in those with or without asthma, and patients with asthma may not readily distinguish the perceived dyspnea of a hyperventilation attack from the acute airway obstruction of asthma. Dyspnea on exertion, in the absence of other symptoms of asthma or an unequivocal response to albuterol, is most likely a result of other causes. Most common is the dyspnea associated with normal exercise limitation, but causes of dyspnea on exertion can include other physiologic abnormalities including exercise-induced vocal cord dysfunction, exercise-induced laryngomalacia, exercise-induced hyperventilation, and exercise-induced supraventricular tachycardia. A careful history, attention to the nature of the respiratory sounds that are present, spirometry, exercise testing, and blood-gas measurement provide useful data to sort out the various causes and avoid inappropriate treatment of these pseudo-asthma clinical manifestations.

Exercise challenge test in 3- to 6-year-old asthmatic children

RATIONALE

The exercise challenge test (ECT) is a common tool to assess exercise-induced asthma (EIA) in school-aged children. EIA has not been explored in the early childhood setting.

OBJECTIVE

To assess the existence of EIA in children in this age group.

MEASUREMENTS AND MAIN RESULTS

A 6-min, controlled, free-run test was performed in 55 children (age range, 3 to 6 years old) who were classified into the following groups: 30 children in whom asthma had been previously diagnosed (group A); and 25 children with prolonged coughing (group B). Spirometry measurements were obtained before the run, and at 1, 2, 3, 5, 10, and 20 min after the run. A positive finding of EIA was defined as a 13% decrease from baseline FEV(1) or baseline forced expiratory volume in the first 0.5 s (FEV(0.5)). The actual duration of each run was age-related (mean [+/- SD] duration, 4.8 +/- 0.8 min). The nadir in indexes occurred after a mean time of 2.98 +/- 1.31 min. A positive EIA finding determined by FEV(1) was present in 15 children, and by FEV(0.5) in 34 children. Twenty-six children were from group A, but only 8 children were from group B. Wheezing and/or prolonged expiration were associated with a positive test result in 31 of 34 children. Coughing was frequent in children with both negative and positive ECT findings.

CONCLUSION

The present study documents for the first time the presence of EIA in response to a free-run test in early childhood. Our findings suggest that a free-run test for the presence of EIA is suitable, but that the running duration is limited by age. The duration of airflow limitation after exercise is significantly earlier and shorter in young children with asthma compared with older children. FEV(0.5) is a better index than the traditional FEV(1) for describing positive ECT results in young children. The association of wheezing and/or prolonged expiration may help in defining EIA in early childhood in the absence of a spirometer.

[The shuttle run test is not valid for the detection of asthma in school physical education programs]

OBJECTIVE

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.

PATIENTS AND METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Cardiopulmonary exercise testing in children and adolescents with asthma who report symptoms of exercise-induced bronchoconstriction

Patients with asthma often report symptoms of exercise-induced bronchoconstriction. We performed cardiopulmonary exercise testing to establish the cause of exercise limitation in patients with asthma, under treatment, who reported symptoms of exercise-induced bronchoconstriction. Ten of the 42 patients meeting criteria for inclusion in our study (24%) developed exercise-induced bronchoconstriction. Exercise limitation without exercise-induced bronchoconstriction was found in both obese and non-obese patients, suggesting that poor fitness is a problem independent of body habitus. Including cardiopulmonary exercise testing in the management of children with suspected exercise-induced bronchoconstriction would provide a better understanding of the etiology of their symptoms and facilitate more appropriate treatment.

Surgical treatment of exercise-induced laryngeal dysfunction

A method for combined ergo-spirometry and continuous laryngeal inspection during exercise, entitled continuous laryngoscopy exercise test (CLE-test) has been developed in order to study airway obstruction at the laryngeal level during exercise. The aim of the study was to apply the CLE-test on patients experiencing respiratory distress during exercise in order to reveal the usefulness of the CLE-test both as a diagnostic tool in the selection of patients for surgery and in evaluation of treatment effects postoperatively. Until now, 81 patients with a history of exercise-induced stridor have undergone the CLE-test. Ten of these patients were selected for surgical treatment based on the severity of symptoms and their motivation for treatment. All ten patients underwent endoscopic supraglottoplasty (ES), with laser incision in both aryepiglottic folds anterior to the cuneiform cartilages and removal of the mucosa around the top of the tubercles. Each patient was examined by the CLE-test before and 3 months after surgery. Eight patients felt subjectively that their breathing capacity during exercise was improved. When pre- and postoperative ergo-spirometry evaluations were compared, increased peak oxygen consumption was observed in four out of ten patients and better maximal minute ventilation in seven out of ten. Postoperative evaluation of the laryngeal images showed less prominent aryepiglottic folds. The typical adduction of the supraglottic structures concomitant with inspiratory stridor found preoperatively was not present in any of the patients during exercise postoperatively. The ES procedure is an efficient surgical treatment for exercise-induced laryngeal supraglottic obstruction and the CLE-test eases the selection of patients for surgery and facilitates the evaluation of treatment effects.

Continuous ratings of breathlessness during exercise by children and young adults with asthma and healthy controls

Although it is recommended and common practise for adults with respiratory disease to rate symptoms (e.g., dyspnea and/or leg discomfort) during exercise testing, there are no reports on whether children can rate their perception of breathlessness during exercise. Our aims were to evaluate the ability of children and young adults with asthma to continuously rate breathlessness on the 0-10 category-ratio (CR-10) scale with a computerized system during cycle ergometry, and to compare their results with those of healthy subjects. At an initial visit, subjects were familiarized with equipment and exercise protocol, and practised rating breathlessness while cycling. At a follow-up visit (2-4 days later), subjects performed incremental exercise and rated breathlessness using a computer system, mouse, and monitor. Changing the position of the mouse caused movement of a vertical bar located adjacent to the CR-10 scale to indicate the severity of breathlessness. Baseline characteristics of the 14 subjects with asthma (age, 15 +/- 3 years) and 33 healthy subjects (age, 16 +/- 2 years) were similar. The two groups had comparable levels of fitness as measured by peak oxygen consumption (VO(2)). Correlations between exercise physiologic variables (power production, VO(2), and minute ventilation) and breathlessness ratings were >0.90. Subjects reported progressively more ratings of breathlessness with increasing exercise intensities. There were no differences between groups for slopes, x-intercepts, and absolute thresholds relating physiologic variables and breathlessness. In conclusion, children and young adults with asthma as well as healthy individuals of comparable age successfully used the computerized system to rate breathlessness continuously during cycle ergometry. Both groups reported more ratings of breathlessness with this technique as exercise progressed.

Differences in the evaluation and management of exercise-induced bronchospasm between family physicians and pulmonologists

Previous studies have demonstrated that specialists and generalists differ in the evaluation and management of asthma especially in terms of use of objective testing. We speculated that there also may be differences in the diagnosis and management of exercise-induced respiratory complaints. An Internet survey was sent to samples of pulmonologists and family physicians. Our data suggests that pulmonologists are much more likely to order bronchoprovocation testing than family physicians, and family physicians are more likely to start any empiric therapy than perform bronchoprovocation testing when exercise-induced bronchospasm is suspected. These differences may lead to inaccurate or missed diagnoses and unnecessary morbidity.

[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.

Highlights in asthma 2005

It is usual at the end of a year for top tens to feature large in our collective consciousness. These inevitably include the occasional controversial selection and without fail will overlook a number of gems, whether in the field of literature, art, or science. The approaches to such compilations include personal selections, convening expert committees through to letting the market decide. However, it is well recognised that experts can be wrong and markets distorted. A novel approach to identifying the key publications in the field of medicine, Faculty of 1000 Medicine (http://www.f1000medicine.com), uses faculty evaluations to assign ratings to published papers within topics and categories, bringing a flavour of the dynamism of post hoc peer review to biological sciences that exists in other fields of scholarship. Archives of Disease in Childhood has also developed a market led system of peer evaluation through its web based top ten most read articles feature.