Screening adolescent athletes for exercise-induced asthma

How to detect young athletes at risk of exercise-induced bronchoconstriction?

Exercise-induced bronchoconstriction (EIB) is a prevalent condition in elite athletes caused by transient airway narrowing during or after exercise. Young athletes nowadays start early to perform high level exercise, highlighting the need to screen for EIB in a younger population. The purpose of this review is to evaluate current evidence of pre-tests with high probability to predict a positive provocation test in young and adolescent athletes, aged 12-24 years and thus indicate whether a young athlete is at risk of having EIB. Up to now, there is no validated screening test available to increase the pre-test probability of a provocation test of EIB in young and adolescent athletes. We would recommend that a clinical guideline committee might consider the development of a flow chart to screen for EIB in adolescent athletes. It could be composed of a symptom-based questionnaire focusing on wheezing during exercise, atopic state, reversibility test (to exclude EIB with asthma) and completed with markers in blood/serum. However, more research is necessary.

Management of Intermittent and Persistent Asthma in Adolescent and High School Athletes

Asthma is the most common chronic condition during childhood and adolescence, affecting an estimated 8% of children and youngsters below 18 years in the United States and the United Kingdom. In adolescent athletes, asthma-like symptoms may represent a common consequence of regular sport practice. Asthma in young athletes poses several challenges, including the ambiguity of definitions and diagnosis of asthma resulting from exercise-induced symptoms, the best pharmacological treatments, and the nonpharmacological options for the management of disease and the challenges inherent to this age group. At a time when the regular practice of sports is increasingly being recommended for a healthy living, the support network around the young athletes is crucial to reduce the impact of asthma on their physical and emotional well-being. In this review, we examine the main issues around the definitions and clinical differentiations of asthma in young sport athletes. We discuss best practice approaches to improve the adherence to the clinical management, including nonpharmacological strategies directed at the family and trainers of athlete adolescents.

High Incidence of Bronchospastic Response to a Stair Climbing Exercise

Background

While it is increasingly recognized that exercise-induced bronchoconstriction (EIB) affects a substantial proportion of sport participants, the relation of EIB incidence and severity to the type and intensity of exertion remains under-investigated. The aim of this study was to establish the incidence and severity of EIB during a stair race, a highly demanding all-out effort exercise. We hypothesized that a large proportion of participants would develop EIB to this particular high-intensity competition, and that among the predisposing factors, severity of EIB would depend on the level of exertion.

Methodology

In this study, screening for EIB was conducted during the official competitive race to a 114-m skyscraper held during the late spring in a city center of approximately 0.5 million residents. Healthy active men (n = 26; age = 32.0 ± 7.0 years) volunteering for the study from the field of the race were included. Allergy Questionnaire for Athletes was completed, and responses of expiratory capacity (forced expiratory volume in the first second, FEV1) and blood lactate were measured by portable digital devices.

Results

On average, FEV1 dropped by 10.5 ± 5.6% after the exercise. In 11 (approximately 42.5%) participants, FEV1 drop was >10%, indicative of clinical EIB. While age, anthropometry, training experience, allergy history, baseline FEV1, and post-exercise lactate did not differ in responders versus non-responders, those with FEV1 decrement of >10% were slower in the race.

Conclusions

Due to very high incidence of EIB observed in active men performing a maximal-effort task and negative association of EIB with competitive performance, the condition of these individuals undertaking regular intense exercise deserves more attention.

Clinical recommendations for cardiopulmonary exercise testing in children with respiratory diseases

INTRODUCTION

Cardiopulmonary exercise testing (CPET) quantitates and qualitates the integrated physiological response of a person to incremental exercise and provides additional information compared to static lung function tests alone.

AREAS COVERED

This review covers rationale for the use of CPET parameters beyond the usual parameters like peak oxygen uptake and peak minute ventilation in children with respiratory disease.

EXPERT OPINION

CPET provides a wealth of data from rest, submaximal and maximal exercise and data during recovery from exercise. In this review, an interpretative approach is described for analyzing CPET data in children with respiratory disease.

Preparticipation Evaluation

Although the specific content has been recommended, debated, and extensively reviewed over the past several decades, the preparticipation evaluation (PPE) has become standard of care for athletes as they prepare for organized athletic participation. The PPE seeks to detect conditions that predispose the athlete to injury or limit full participation in certain activities. Of particular interest, underlying cardiovascular and musculoskeletal conditions are sought because they are frequently associated with mortality and morbidity in athletes.

Global prevalence of exercise-induced bronchoconstriction in childhood: A meta-analysis

AIM

This systematic review and meta-analysis aimed to estimate the global prevalence of exercise-induced bronchoconstriction (EIB) in children and adolescents.

METHOD

We searched PubMed, Google Scholar, and the Virtual Health Library-BIREME from inception to December 23, 2017. We selected observational studies that reported the prevalence of EIB (diagnosed by exercise challenge test) in children and adolescents aged 5-18 years. We conducted random-effects meta-analyses to estimate the pooled prevalence of EIB and 95% CI.

RESULTS

We included 66 studies (55 696 participants, 5670 cases of EIB) in the review, of which 33 in general population of children and adolescents, 10 in child and adolescent athletes and 23 in children and adolescents with asthma. The global mean prevalence of EIB in the general population of children and adolescents was 9% (IC95%: 8-10%), with a higher rate (12%) in Asia-Pacific and America. The mean prevalence of EIB was 15% (95% CI: 9-21%) in child and adolescent athletes, and 46% (95% CI: 39-53%) in children and adolescents with asthma. We estimated that, globally, around 16.5 million (95% CI: 15-18 million) children and adolescents up to 18 years of age may have EIB.

CONCLUSION

EIB in childhood should be considered as a global public health problem that needs more attention. The substantial heterogeneity between studies highlights the need for evidence-based guidelines for diagnosis of EIB in this age group.

National Athletic Trainers' Association position statement: Preparticipation physical examinations and disqualifying conditions

OBJECTIVE

To present athletic trainers with recommendations for the content and administration of the preparticipation physical examination (PPE) as well as considerations for determining safe participation in sports and identifying disqualifying conditions.

BACKGROUND

Preparticipation physical examinations have been used routinely for nearly 40 years. However, considerable debate exists as to their efficacy due to the lack of standardization in the process and the lack of conformity in the information that is gathered. With the continuing rise in sports participation at all levels and the growing number of reported cases of sudden death in organized athletics, the sports medicine community should consider adopting a standardized process for conducting the PPE to protect all parties.

RECOMMENDATIONS

Recommendations are provided to equip the sports medicine community with the tools necessary to conduct the PPE as effectively and efficiently as possible using available scientific evidence and best practices. In addition, the recommendations will help clinicians identify those conditions that may threaten the health and safety of participants in organized sports, may require further evaluation and intervention, or may result in potential disqualification.

Chronic pulmonary embolism in a young athletic woman

Exercise-induced dyspnea (EID) is a common complaint in young athletes. Exercise-induced bronchospasm (EIB) is the most common cause of EID in healthy athletes, but it is important to recognize more serious pathology. Herein we present the case of an 18-year-old woman with a 1.5-year history of EID. She had been treated for EIB without relief. Her arterial oxygen saturation was 88% during exercise testing. Computed tomographic angiography to assess for vascular abnormalities identified a large thrombus in the main pulmonary trunk. Symptoms markedly improved with therapeutic anticoagulation. Massive pulmonary embolus is an exceedingly rare etiology of exertional dyspnea in young athletes. Hypoxemia during exercise testing was an important clue that something more ominous was lurking that required definitive diagnosis.

Effect of Submaximal Warm-up Exercise on Exercise-induced Asthma in African School Children

BACKGROUND

Regular physical activity has long been regarded as an important component of a healthy lifestyle. Exercise-induced asthma (EIA) is one of the major problems interfering with the performance of exercise. A warm-up exercise programme has been cited as a non-pharmacologic means of reducing EIA, but its effect has not been fully elucidated.

OBJECTIVE

The aims of this study were to determine the prevalence of unrecognized EIA in Pretoria primary school children, determine the effect of a warm-up exercise programme on EIA and to establish the relationship between history of allergy, family history of asthma and EIA.

METHODS

A random sample of 640 school children was selected. The study was divided into three phases. In phase one, a descriptive cross-sectional study was done using the standardized European Community Respiratory Health Survey (ECRHS) questionnaire. In phase two, non-asthmatic participants that returned a completed questionnaire were included in the field study. Pre-test and post-test experimental designs were used, where peak expiratory flow rate (PEFR) was measured at baseline and within ten minutes after exercise. A total of 340 subjects completed the Free Running Asthma Screening Test (FRAST); EIA was defined as a decrease in baseline PEFR ≥ 10% after exercise and 75 children (22%) had EIA. In phase three, 29 of the 75 subjects participated in the warm-up programme which was performed in the laboratory and subjects acted as their own controls. Predefined protocols for the study were followed.

RESULTS

Seventy-five (22%) of the 340 participants had EIA. The mean age, height and weight were 10.51 years, 139.26 cm and 33.45 kg, respectively. Exercise-induced asthma symptoms were cough (25%), chest pain (16%), wheeze (12%) and chest tightness (12%). The history of allergy was 75%, family history of allergy 40% and positive history of allergy when near animals, feathers or in dusty areas 38%. Wheezing during or after exercise, wheezing when near animals, feathers or in dusty areas and chest pain was significant (p < 0.05). The mean PEFR after exercise without warm-up was 4.43 L/min. The mean PEFR after exercise (warm-up) was 4.98. The mean percentage change in PEFR between exercise without warm-up and exercise with warm-up was 14.83%. The paired t-test showed a significant difference between PEFR with warm-up and PEFR without warm-up (p < 0.05).

CONCLUSION

There was a high prevalence of EIA among study participants. Exercise-induced asthma symptoms were significant for wheezing and chest pain. Exercise after warm-up was significant in reducing EIA. This study reports the effect of warm-up exercise on EIA and highlights the need to screen school children for EIA.

Dyspneic athlete

Breathing concerns in athletes are common and can be due to a wide variety of pathology. The most common etiologies are exercise-induced bronchoconstriction (EIB) and paradoxic vocal fold movement disorder (PVFMD). Although some patients may have both, PVFMD is often misdiagnosed as EIB, which can lead to unnecessary treatment. The history and physical exam are important to rule out life threatening pulmonary and cardiac causes as well as common conditions such as gastroesophageal reflux disease, sinusitis, and allergic etiologies. The history and physical exam have been shown to be not as vital in diagnosing EIB and PVFMD. Improvement in diagnostic testing with office base spirometry, bronchoprovocation testing, eucapnic voluntary hyperpnea (EVH) and video laryngoscopy are essential in properly diagnosing these conditions. Accurate diagnosis leads to proper management, which is essential to avoid unnecessary testing and save healthcare costs. Also important to the physician treating dyspnea in athletes is knowing regulations on medications, drug testing, and proper documentation needed for certain organizations. The differential diagnosis of dyspnea is broad and is not limited to EIB and PVFMD. Ruling out life threatening cardiac and pulmonary causes with a proper history, physical, and appropriate testing is essential. The purpose of this review is to highlight recent literature on the diagnosis and management of EIB and PVFMD as well as discuss other potential causes for dyspnea in the athlete.

Incidence of exercise-induced asthma in adolescent athletes under different training and environmental conditions

The aim of this study was to establish if there were differences in the incidence of exercise-induced bronchospasm between athletes in different sports, which take place under different environmental conditions such as open places, closed courses, and swimming pools with similar exercise intensity (football, basketball, water polo) using the free running test. The study included 90 adolescents (3 groups of 30) aged 14-18 years recruited from academies in northern Greece. All the participants were initially subjected to (a) a clinical examination and cardiorespiratory assessment by a physician and (b) free running test of a 6-minute duration and measurement with a microspirometer of the forced expiratory volume in 1 second (FEV₁). Only the participants who had measured a decrease in FEV₁ ≥ 10% were reevaluated with the microspirometer during a training session. The examination of all the participants during the free running test showed that 22 athletes, that is, 9, 8, and 5 of football, basketball, and water polo athletes, respectively, demonstrated an FEV₁ ≥ 10 drop. Reevaluation of the 22 participants during training showed that 5 out 9 (55%) football athletes, 4 out of 8 basketball athletes (50%), and none of the 5 athletes of the water polo team displayed a drop of FEV₁ ≥ 10%. Despite the absence of any significant statistical differences between the 3 groups, the analysis of variances did show a trend of a lower incidence of EIA in the water polo athletes. It was found that a football or basketball game can induce EIA in young athletes but to a lesser degree than the free running test can induce. The water polo can be a safer sport even for participants with a medical history of asthma or allergies.

The use of step tests for the assessment of exercise capacity in healthy subjects and in patients with chronic lung disease

Step tests are typically used to assess exercise capacity. Given the diversity of step tests, the aim of this review was to describe the protocols that have been used in healthy subjects and in patients with chronic lung disease. Step tests for use in healthy subjects have undergone a number of modifications over the years. In most step tests, the duration is variable (90 s-10 min), but the step height (23.0-50.8 cm) and stepping rate (22.5-35.0 steps/min) remain constant throughout the test. However, the use of a fixed step height and constant stepping rate might not provide adequate work intensity for subjects with different levels of fitness, the workload therefore being above or below individual capacity. Consequently, step test protocols have been modified by introducing changes in step heights and stepping rates during the test. Step tests have been used in patients with chronic lung diseases since the late 1970s. The protocols are quite varied, with adjustments in step height (15-30 cm), pacing (self-paced or externally paced), and test duration (90 s-10 min). However, the diversity of step test protocols and the variety of outcomes studied preclude the determination of the best protocol for use in individuals with chronic lung disease. Shorter protocols with a high stepping rate would seem to be more appropriate for assessing exercise-related oxygen desaturation in chronic lung disease. Symptom-limited testing would be more appropriate for evaluating exercise tolerance. There is a need for studies comparing different step test protocols, in terms of their reliability, validity, and ability to quantify responses to interventions, especially in individuals with lung disease.

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.

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.

Prevalence of exercise-induced bronchoconstriction in teenage football players in Tunisia

BACKGROUND AND OBJECTIVES

Studies on exercise-induced bronchoconstriction (EIB) in team sports are lacking. The aim of this study was to screen for EIB among amateur teenage football players in Tunisia and to compare EIB prevalence between regions.

METHODS

One hundred ninety-six male football players (mean age [SD], 13.5 [0.5] yrs), practicing in three different cities of Tunisia (Tunis, Sousse and Sfax), underwent an outdoor free run of 7 minutes. Forced expiratory volume in one second (FEV subset1) was recorded prior to and at 0, 3, 5, 10, 15, 20 and 30 minutes after the run. Players were screened for EIB positivity defined as a greater than 10% decline in FEV subset1 from the resting value at any timepoint.

RESULTS

FEV1 decreased more than 10% in 30% of the players. EIB positivity was more common in Sfax (15.8%) than in Tunis (7.7%) (P=.03). Air humidity during the study was higher in Tunis.

CONCLUSION

EIB is prevalent among amateur teenage football players in Tunisia. The prevalence differs between regions and seems to be dependent on air humidity levels.

Exercise-induced asthma, respiratory and allergic disorders in elite athletes: epidemiology, mechanisms and diagnosis: part I of the report from the Joint Task Force of the European Respiratory Society (ERS) and the European Academy of Allergy and Clinical Immunology (EAACI) in cooperation with GA2LEN

AIMS

To analyze the changes in the prevalence of asthma, bronchial hyperresponsiveness (BHR) and allergies in elite athletes over the past years, to review the specific pathogenetic features of these conditions and to make recommendations for their diagnosis.

METHODS

The Task Force reviewed present literature by searching Medline up to November 2006 for relevant papers by the search words: asthma, bronchial responsiveness, EIB, athletes and sports. Sign criteria were used to assess level of evidence and grades of recommendation.

RESULTS

The problems of sports-related asthma and allergy are outlined. Epidemiological evidence for an increased prevalence of asthma and BHR among competitive athletes, especially in endurance sports, is provided. The mechanisms for development of asthma and bronchial hyperresponsiveness in athletes are outlined. Criteria are given for the diagnosis of asthma and exercise induced asthma in the athlete.

CONCLUSIONS

The prevalence of asthma and bronchial hyperresponsiveness is markedly increased in athletes, especially within endurance sports. Environmental factors often contribute. Recommendations for the diagnosis of asthma in athletes are outlined.

Pulmonary disorders in the training room

For the athlete, not only can pulmonary disorders cause significant alterations in training schedules or even prolonged stoppages, they can be life-threatening. Infectious diseases such as acute bronchitis, influenza, and pneumonia conspire to disrupt exercise regimens. Pneumothorax, vocal cord dysfunction, and exercise-induced asthma may present diagnostic and treatment challenges. Obstructive sleep apnea not only causes disruptive symptoms but can be associated with significant cardiovascular morbidity and even mortality. This article addresses the most common pulmonary conditions athletes face and provides a framework for the diagnosis and treatment of these conditions.

Exercise-induced bronchospasm among healthy elite cross country skiers and non-athletic students

Regular exercise in cold, dry air is believed to be a predisposing factor for exercise-induced bronchospasm (EIB). The aim of this study was to compare the occurrence of EIB among previously healthy elite cross country skiers and their non-athletic control subjects. Twenty healthy elite cross country skiers and 18 non-asthmatic controls were challenged by a standardized free exercise test. Thereafter, subjects' respiratory function was followed by flow-volume spirometry up to 30 min. EIB was defined in the post-exercise spirometry as at least one of the following: a >or=10% decrease in forced expiratory volume in 1 s (FEV1), a >or=20% decrease in mean maximal expiratory flow (MMEF) or a >or=25% decrease in peak expiratory flow rate (PEF). EIB was found in two skiers and one control according to FEV1, for seven skiers and two controls according to MMEF. Two skiers and one control had exercise-induced asthma (EIA) according to both parameters. The largest decrease in PEF was 13%, that did not result in additional diagnoses. All nine of the subjects with a positive test result reported asthma-like symptoms (dyspnea, cough or increased mucus excretion) after the exercise challenge. Accordingly, seven previously healthy skiers (35%) and two controls (11%) were diagnosed as having EIB. In addition, three skiers of the original cohort were excluded because of an earlier asthma diagnosis, making the total asthma prevalence 10/23 (42%) among the elite skiers. It was concluded that EIB is more common in elite cross country skiers than in non-athletic controls. The bronchoconstriction induced by exercise is usually mild or moderate, and flow-volume spirometry with sensitive flow parameters is needed for it to be diagnosed. Even a mild asthma decreases minute ventilation and maximal performance of winter sport athletes. Therefore, skiers with long-term respiratory symptoms or decreased performance should be studied for EIA and treated adequately.

Prevalence of exercise-induced bronchospasm in long distance runners trained in cold weather

We investigated whether regular training in cold weather has an effect on the development of exercise-induced bronchospasm. Nineteen sedentary males and 20 male long distance runners who were regularly training in Erzurum participated in this study. They had no history of asthma, atopy or allergic rhinitis. Pre- and post-exercise spirometry was performed in the participants in room temperature. EIB was defined as at least a > or =10% fall in FEV1 or a > or =15% fall in FEF(25-75%) or a > or =25% fall in PEFR. EIB was established in 7 of 20 athletes and in 1 of 19 sedentaries. Prevalence of EIB will be higher even if it is established in room temperature when training for the sports like long distance running which is not a cold weather sport. We conclude that it will be more convenient to establish EIB in room temperature and in the laboratory since the exercise test and spirometry can be performed more accurately under more standard conditions.

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.

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

BACKGROUND

A questionnaire alone may not be an adequate screening tool for asthma.

OBJECTIVE

To determine whether an asthma questionnaire used in combination with an exercise step test is better than a questionnaire alone in screening for asthma in children and to evaluate the validity of a rhinitis questionnaire in determining atopy.

METHODS

The International Study of Asthma and Allergies in Childhood (ISAAC) asthma core questionnaire was used to screen for asthma in 307 inner-city first through third graders. All children who had scores consistent with a diagnosis of asthma underwent step testing, as did a subset of children who had negative overall scores. All children who had inconsistent asthma scores and step test results underwent methacholine challenge testing. The same 307 children underwent rhinitis screening and children who had one or more positive responses on the ISAAC rhinitis questionnaire underwent skin testing as did a subset of children who had all negative responses.

RESULTS

Three hundred of 307 asthma and rhinitis questionnaires were returned. Twenty-eight children (9%) had global asthma scores that were considered to be positive (5 or above). Twenty-four of these children underwent step testing as did 34 randomly selected children who had negative global asthma scores. Thirty-one (91%) of the 34 children who had negative global asthma scores had negative step tests. Similarly, 20 of 24 children (83%) of the children who had positive global asthma scores had negative step tests. Only 4 children who had positive global asthma scores were step test-positive or had reversible airway obstruction at baseline. Using a positive methacholine challenge as the gold standard for establishing bronchial hyperresponsiveness, the global asthma score derived from the eight-item ISAAC asthma questionnaire yielded a sensitivity of 64%, a specificity of 11%, a positive predictive value of 47%, and a negative predictive value of 20%. Comparing the six-item ISAAC rhinitis questionnaire results to the gold standard, skin test reactivity, the questionnaire yielded a sensitivity of 76%, a specificity of 21%, a positive predictive value of 56%, and a negative predictive value of 40%.

CONCLUSIONS

Step testing was not useful as a screening tool for asthma. In addition, the ISAAC asthma questionnaire may not be a good asthma screening tool for inner-city pediatric populations, especially if the form is self-administered. Investigators should first validate both the ISAAC asthma and rhinitis screening questionnaires in the particular population to be studied before widespread asthma and allergy screening efforts are initiated using these tools.

Is asthma over- or under-diagnosed in athletes?

A high prevalence of asthma has been reported in athletes. However, studies in this population usually show an even higher prevalence of airway hyperresponsiveness (AHR) and exercise-induced bronchoconstriction (EIB). This report compares studies on self-reported or physician-diagnosed asthma in athletes with those using objective measures of airflow limitation or airway responsiveness. The higher prevalence of AHR (or EIB) measured in athletes, when compared with the prevalence of self-reported or physician-diagnosed asthma, suggests that abnormal airway responses are common in athletes, although they are infrequently associated with troublesome respiratory symptoms. This may indicate underdiagnosis of asthma in athletes, possibly due to an underreporting of respiratory symptoms or a reduction in perception of nociceptive sensations with repeated exercise over time, or it may simply mean that high-level training is associated with asymptomatic AHR. In athletes, as in the general population, the use of subjective methods such as surveys and questionnaires results in an underestimation ofthe prevalence of airway dysfunction when compared with objective measurements. The significance of these observations is unknown, and there is a need to determine their long-term consequences for athletes.

Prevalence of obstructive airflow limitation in Irish collegiate athletes

BACKGROUND

Asthma prevalence in athletes is variable, depending on the sport and training conditions.

AIMS

To investigate the prevalence of obstructive airflow limitation, asthma control and lung volume differences in a control group and five groups of collegiate athletes--outdoor field, indoor court, endurance, combat sports and swimming.

METHODS

Three hundred and five athletes completed a respiratory questionnaire and performed spirometry during normal training conditions, to determine FEV1, FVC and PEFR pre- and at 5, 10 and 15 minutes post-exercise. Between and within group analysis was carried out using single factor and repeated measures ANOVA.

RESULTS

Previous diagnosis of asthma was reported by 24%, outdoor field sports 4.9%, indoor court sports 2.3%, endurance events 2.6%, combat sports 3%, swimming 6.9% and controls 4.3%. Mean FEV1 and FVC data, expressed as percentage of predicted, were greatest in swimming and lowest in controls. Swimming showed a significant rise in FEV1 post-exercise, indoor court and endurance sports demonstrated no change and outdoor field, combat and control groups showed a fall in FEV1 post-exercise.

CONCLUSION

Warm humid training conditions appear protective against exercise-induced asthma. The greatest reductions in lung volumes occurred following high intensity exercise under cool conditions in the poorly aerobically conditioned.

Exercise-induced bronchospasm in the elite athlete

The term exercise-induced bronchospasm (EIB) describes the acute transient airway narrowing that occurs during and most often after exercise in 10 to 50% of elite athletes, depending upon the sport examined. Although multiple factors are unquestionably involved in the EIB response, airway drying caused by a high exercise-ventilation rate is primary in most cases. The severity of this reaction reflects the allergic predisposition of the athlete, the water content of the inspired air, the type and concentration of air pollutants inspired, and the intensity (or ventilation rate) of the exercise. The highest prevalence of EIB is seen in winter-sport populations, where athletes are chronically exposed to cold dry air and/or environmental pollutants found in indoor ice arenas. When airway surface liquid lost during the natural warming and humidification process of respiration is not replenished at a rate equal to the loss, the ensuing osmolarity change stimulates the release of inflammatory mediators and results in bronchospasm; this cascade of events is exacerbated by airway inflammation and airway remodelling. The acute EIB response is characterised by airway smooth muscle contraction, membrane swelling, and/or mucus plug formation. Evidence suggests that histamine, leukotrienes and prostanoids are likely mediators for this response. Although the presence of symptoms and a basic physical examination are marginally effective, objective measures of lung function should be used for accurate and reliable diagnosis of EIB. Diagnosis should include baseline spirometry, followed by an appropriate bronchial provocation test. To date, the best test to confirm EIB may simply be standard pulmonary function testing before and after high-intensity dry air exercise. A 10% post-challenge fall in forced expiratory volume in 1 second is used as diagnostic criteria. The goal of medical intervention is to limit EIB exacerbation and allow the athlete to train and compete symptom free. This is attempted through daily controller medications such as inhaled corticosteroids or by the prophylactic use of medications before exercise. In many cases, EIB is difficult to control. These and other data suggest that EIB in the elite athlete is in contrast with classic asthma.

Effectiveness of screening examinations to detect unrecognized exercise-induced bronchoconstriction

OBJECTIVE

To determine if a physician-administered physical examination and screening questionnaire accurately detects exercise-induced bronchoconstriction (EIB) in adolescent athletes.

STUDY DESIGN

Cross-sectional study of 256 adolescents participating in organized sports from 3 suburban high schools. The number of persons screened positive for EIB by physical examination and questionnaire was compared with the number of persons with EIB diagnosed by a "gold standard" test that consisted of a 7-minute exercise challenge followed by serial spirometry.

RESULTS

We diagnosed EIB in 9.4% of adolescent athletes. The screening history identified persons with symptoms or a previous diagnosis suggestive of EIB in 39.5% of the participants, but only 12.9% of these persons actually had EIB. Among adolescents with a negative review of symptoms of asthma or EIB, 7.8% had EIB. Among adolescents with no previous diagnosis of asthma, allergic rhinitis, or EIB, 7.2% had EIB diagnosed by exercise challenge. Persons who screened negative on all questions about symptoms or history of asthma, EIB, and allergic rhinitis accounted for 45.8% of the adolescents with EIB.

CONCLUSIONS

EIB occurs frequently in adolescent athletes, and screening by physical examination and medical history does not accurately detect it.

A sport-specific protocol for diagnosing exercise-induced asthma in cross-country skiers

OBJECTIVE

This study evaluates a sport-specific protocol to evaluate cross-country skiers for exercise-induced asthma (EIA).

STUDY DESIGN

Participants completed an asthma symptom questionnaire prior to participation. They were then tested by portable digital spirometer with measurements prior to exercise and at 5-minute increments following a 15-minute cross-country skiing exercise session on a groomed ski trail.

SETTING

All spirometry measurements were collected indoors at Nordic ski areas in the Duluth, Minnesota, area. Each ski area was groomed for both skating and classical technique.

SUBJECTS

99 high school skiers, 55 female and 44 male, of various skill levels were tested. All were members of their respective high school cross-country ski team. Testing was open to all ski team members. Skiers from seven different high schools participated.

MAIN OUTCOME MEASURES

Bronchial hyperresponsiveness to exercise measured by the change in forced expiratory volume at 1 s (FEV1) following exercise. A result was considered positive if the decrement in FEV1 was greater than 10% in any two of the postexercise test increments in comparison with the preexercise baseline.

RESULTS

28 of 99 (28%) skiers met the criteria for EIA. No significant differences were found with regards to gender, age, or previous experience. Several individual items on the Asthma Symptom Questionnaire were associated with a positive spirometry test.

CONCLUSIONS

Using a simple protocol of pre- and postexercise spirometry with a defined exercise challenge, a large number of athletes were screened objectively for this condition. Both the equipment and protocol worked well in the field environment and could easily be adapted to most any sports environment.

Prevalence and mechanisms of development of asthma and airway hyperresponsiveness in athletes

A high prevalence of asthma and airway hyperresponsiveness (AHR) has been reported in the athlete population. Factors potentially predisposing athletes to these conditions have not been clearly identified. Although moderate exercise has been shown to be beneficial in patients with asthma, repeated high-intensity exercise could possibly contribute to the development of asthma and AHR. This report provides an overview of the prevalence and possible mechanisms of development of asthma and AHR in the athlete population. The prevalence of asthma and AHR are higher in athletes than in the general population, particularly in swimmers and athletes performing sports in cold air environments. Possible mechanisms involved in the development of asthma in athletes are still uncertain; however, the content and physical characteristics of the inhaled air seem to be important factors, while immune and neurohumoral influences could play a modulatory role. This report stresses the need for further studies to better define the aetiologic factors and mechanisms involved in the development of asthma and AHR in athletes, and proposes relevant preventive and therapeutic measures.

Exercise-induced bronchospasm prevalence in collegiate cross-country runners

PURPOSE

The purpose of this study was to determine the prevalence of exercise-induced bronchospasm (EIB) in collegiate cross-country runners using a protocol involving an intense exercise challenge conducted in the same environment in which the athletes train and compete.

METHODS

One-hundred eighteen collegiate cross-country runners from the Los Angeles, California, metropolitan area participated in the study. All testing took place on a track at the time and location of a normal practice session. The baseline peak expiratory flow rate (PEFR) measurements (best of three) and preexercise heart rate were recorded, after which the athletes ran 2000 m on a track at 85% of maximum heart rate. The postexercise heart rate was recorded and then PEFR measurements at 2, 5, 10, and 30 min after exercise were recorded. The athletes completed a 16-item questionnaire regarding asthma symptoms and health history. Those athletes with a history of asthma and currently taking medications for the asthma were then excluded from statistical analysis of the questionnaire responses. A decrease in PEFR of 15% was considered positive for EIB.

RESULTS

Of the 114 athletes not currently taking medications for asthma, at least 14% (16 athletes) were EIB positive. There was a poor correlation between reported symptoms of asthma and testing positive for EIB.

CONCLUSION

This study demonstrates a high prevalence of EIB in collegiate cross-country runners (at least 14%) and that reported symptoms are a poor predictor of actual EIB.

Exercise-induced asthma

Exercise-induced asthma (EIA) is a common condition that can impede physical activity, particularly for children, adolescents, and young adults. A detailed patient history can help the physician identify subtle EIA clues such as fatigue or poorer performance than training would predict. A careful physical exam can help rule out conditions that mimic EIA such as respiratory infections or cardiac conditions. Pulmonary function testing is often useful for assessing severity and establishing a baseline for assessing treatment efficacy. Treatment options include nonpharmacologic measures that address the exercise environment and warm-up routines. Several medication options and combinations can help patients avoid symptoms and participate fully in fitness and sports activities.

Exercise-induced bronchospasm in high school athletes via a free running test: incidence and epidemiology

BACKGROUND

Exercise-induced bronchospasm (EIB) affects up to 35% of athletes and up to 90% of asthmatics. Asthma morbidity and mortality have increased over the past several decades among residents of Philadelphia, PA. It is possible that a simple free running test for EIB may serve as a tool to study the factors contributing to recent trends in asthma, and to screen for asthma in athletes in the urban setting.

OBJECTIVES

The purposes of this study were to (1) assess a free running test to screen for EIB, and (2) examine prevalence of and epidemiologic factors associated with EIB in high school athletes.

DESIGN

Cross-sectional observational study on the incidence and risk factors for EIB. To validate our method and criteria for the diagnosis of EIB, a repeat test was performed on a portion of the athletes. In a randomized single-blinded fashion, 15 athletes who had demonstrated EIB initially received albuterol or placebo prior to a repeat exercise test.

SETTING

Community high school athletic facilities.

PARTICIPANTS

We studied 238 male high school varsity football players.

INTERVENTION

All athletes underwent an acquaintance session with a questionnaire, followed by a 1-mile outdoor run (6 to 8 mins).

MEASUREMENTS

Peak expiratory flow (PEF) measurements were determined prior to and 5, 15, and 30 min after exercise. Heart rates (HRs) and dyspnea scores were measured. EIB was defined as a decrease of 15% in PEF at any time point after exercise. Associations of EIB with demographic factors were assessed by univariate and multivariate analyses.

RESULTS

Two hundred thirty-eight athletes participated: 92 European-Americans (EA), 140 African-Americans (AA), 5 Hispanics, and 1 Native American. Mean age was 16+/-1 years. Average HR postexercise was 156+/-24 beats/min. Twenty-four (10%) reported a history of treated asthma. The prevalence of EIB among the remaining 214 athletes was 19 of 214 (9%). The rate of EIB among AA athletes was higher than among EA athletes: (17/126 [13%] AA vs 2/82 [2%] EA, p = 0.01). During the validation portion of the study, the placebo-treated group (n = 7) demonstrated a consistent drop in PEF after exercise on repeat testing, with a 16+/-5% fall in PEF on initial testing and a 14+/-13 drop with placebo. In contrast, the fall in airflow in the albuterol-treated athletes (n = 8) following exercise reversed with albuterol treatment, from a 15+/-6% fall in PEF at initial testing to an increase in PEF of 6+/-9% from baseline following albuterol administration. A history of wheezing (p < 0.001), residence in a poverty area (p < 0.0001), race (p = 0.01), remote history of asthma (p < 0.001), and absolute water content of the air on the day tested (p = 0.04) were significantly associated with EIB. By stepwise regression, EIB was most closely associated with a history of wheezing (p = 0.001) and poverty area residence (p = 0.003).

CONCLUSIONS

Our findings indicate a substantial rate of unrecognized EIB exists among urban varsity athletes, and suggest that active screening for EIB, especially for students residing in poverty areas, may be indicated to identify individuals at risk for EIB and asthma.