Eucapnic Voluntary Hyperventilation to Detect Exercise-Induced Bronchoconstriction in Cystic Fibrosis.

BACKGROUND: Exercise-induced bronchoconstriction (EIB) has not been well studied in cystic fibrosis (CF), and eucapnic voluntary hyperventilation (EVH) testing has not been used as an objective assessment of EIB in CF to date. METHODS: A prospective cohort pilot study was completed where standard EVH testing was completed by 10 CF patients with forced expiratory volume in 1 s (FEV1) ≥70% of predicted. All patients also completed a cardiopulmonary exercise test (CPET) with pre- and post-CPET spirometry as a comparative method of detecting EIB. RESULTS: No adverse events occurred with EVH testing. A total of 20% (2/10) patients were diagnosed with EIB by means of EVH. Both patients had clinical symptoms consistent with EIB. No patient had a CPET-based exercise challenge consistent with EIB. CONCLUSIONS: EVH testing was safe and effective in the objective assessment for EIB in patients with CF who had well-preserved lung function. It may be a more sensitive method of detecting EIB then exercise challenge.

An official American Thoracic Society clinical practice guideline: exercise-induced bronchoconstriction.

BACKGROUND: Exercise-induced bronchoconstriction (EIB) describes acute airway narrowing that occurs as a result of exercise. EIB occurs in a substantial proportion of patients with asthma, but may also occur in individuals without known asthma. METHODS: To provide clinicians with practical guidance, a multidisciplinary panel of stakeholders was convened to review the pathogenesis of EIB and to develop evidence-based guidelines for the diagnosis and treatment of EIB. The evidence was appraised and recommendations were formulated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: Recommendations for the treatment of EIB were developed. The quality of evidence supporting the recommendations was variable, ranging from low to high. A strong recommendation was made for using a short-acting ß(2)-agonist before exercise in all patients with EIB. For patients who continue to have symptoms of EIB despite the administration of a short-acting ß(2)-agonist before exercise, strong recommendations were made for a daily inhaled corticosteroid, a daily leukotriene receptor antagonist, or a mast cell stabilizing agent before exercise. CONCLUSIONS: The recommendations in this Guideline reflect the currently available evidence. New clinical research data will necessitate a revision and update in the future.

Exercise-induced bronchospasm, asthma control, and obesity.

Exercise-induced bronchospasm (EIB) commonly affects patients with asthma. However, the relationship between EIB and asthma control remains unclear. Exercise limitation due to asthma might lead to reduced physical activity, but little information is available regarding obesity and EIB in asthma. A recent survey evaluated the frequency of EIB and exercise-related respiratory symptoms in a large number of patients with asthma. The survey results were reanalyzed to address any relationship between EIB and asthma control and obesity. A nationwide random sample of children aged 4-12 years (n = 250), adolescents aged 13-17 years (n = 266), and adults aged ≥18 years (n = 1001) with asthma were interviewed by telephone. Questions in the survey addressed asthma symptoms in general, medication use, and height and weight. Asthma control was categorized using established methods in the Expert Panel Report 3. Body mass index (BMI) was calculated using standard nomograms and obesity was defined as a BMI ≥ 30 kg/m(2). Most children (77.6%), adolescents (71.1%), and adults (83.1%) had either "not well" or "very poorly" controlled asthma. Children with "not well" controlled asthma reported a history of EIB significantly more often than those with "well" controlled" asthma. Asthma patients of all ages who had "not well" and "very poorly" controlled asthma described multiple (four or more) exercise-related respiratory symptoms significantly more often than those with "well-controlled" asthma. Obesity was significantly more common in adolescents with "not well" and "very poorly" controlled asthma and adults with "very poorly" controlled asthma. Children, adolescents, and adults with asthma infrequently have well-controlled disease. A history of EIB and exercise-related respiratory symptoms occur more commonly in patients with not well and very poorly controlled asthma. Obesity was found more often in adolescents and adults, but not children, with asthma, which was not well and very poorly controlled.

Screening for exercise-induced bronchoconstriction in college athletes.

OBJECTIVE: Previous studies have reported that the prevalence of exercise-induced bronchoconstriction (EIB) in athletes is higher than that of the general population. There is increasing evidence that athletes fail to recognize and report symptoms of EIB. As a result, there has been debate whether athletes should be screened for EIB, particularly in high-risk sports. METHODS: We prospectively studied 144 athletes from six different varsity sports at a large National Collegiate Athletic Association Division I collegiate athletic program. Baseline demographics and medical history were obtained and the presence of asthma symptoms during exercise was documented. Each athlete subsequently underwent a eucapnic voluntary hyperventilation (EVH) test to document the presence of EIB. Exhaled nitric oxide (eNO) quantification was performed immediately before EVH testing. EIB was defined as a ≥10% decline in forced expiratory volume in 1 second compared with baseline. RESULTS: Only 4 of 144 (2.7%) athletes were EIB-positive after EVH testing. The presence of symptoms was not predictive of EIB as only 2 of the 64 symptomatic athletes (3%) were EIB-positive based on EVH testing. Two of the four athletes who were found to be EIB-positive denied such symptoms. The mean baseline eNO in the four EIB-positive athletes was 13.25 parts per billion (ppb) and 24.5 ppb in the EIB-negative athletes. CONCLUSIONS: Our data argue that screening for EIB is not recommended given the surprisingly low prevalence of EIB in the population we studied. In addition, the presence or absence of symptoms was not predictive of EIB and eNO testing was not effective in predicting EIB.

Managing respiratory problems in athletes.

Respiratory problems are common in athletes of all abilities and can significantly impact upon their health and performance. In this article, we provide an overview of respiratory physiology in athletes. We also discuss the assessment and management of common clinical respiratory conditions as they pertain to athletes, including airways disease, respiratory tract infection and pneumothorax. We focus on providing a pragmatic approach and highlight important caveats for the physician treating respiratory conditions in this highly specific population.

Vocal cord dysfunction and asthma.

PURPOSE OF REVIEW: Vocal cord dysfunction can occur independently or can co-exist with asthma. It often mimics asthma in presentation and can be challenging to diagnose, particularly in those with known asthma. Vocal cord dysfunction remains under-recognized, which may result in unnecessary adjustments to asthma medicines and increased patient morbidity. There is a need to review current literature to explore current theories regarding disease presentation, diagnosis, and treatment. RECENT FINDINGS: The underlying cause of vocal cord dysfunction is likely multifactorial but there has been increased interest in hyper-responsiveness of the larynx. Many intrinsic and extrinsic triggers have been identified which in part may explain asthma-like symptomatology. A variety of techniques have been reported to provoke vocal cord dysfunction during testing which may improve diagnosis. There is a significant gap in the literature regarding specific laryngeal control techniques, duration of therapy, and the effectiveness of laryngeal control as a treatment modality. SUMMARY: Those with vocal cord dysfunction and asthma report more symptoms on standardized asthma control questionnaires, which can result in increasing amounts of medication if vocal cord dysfunction is not identified and managed appropriately. Clinicians need to maintain a high index of suspicion to identify these patients. Videolaryngostroboscopy remains the diagnostic method of choice. Evidence-based guidelines are needed for the most effective diagnostic techniques. Laryngeal control taught by speech pathologists is the most common treatment. Effectiveness is supported in case reports and clinical experience, but not in larger randomized trials which are needed.

Exercise-induced bronchospasm in children with asthma in the United States: results from the Exercise-Induced Bronchospasm Landmark Survey.

Despite the availability of effective therapies, uncontrolled asthma remains a common problem. Previous large surveys suggest that exercise-related respiratory symptoms may be a significant element of uncontrolled asthma. The Exercise-Induced Bronchospasm (EIB) Landmark Survey is the first comprehensive, national survey evaluating EIB awareness and impact among the general public, asthma patients, and health care providers. This study was designed to evaluate the prevalence and impact of exercise-related respiratory symptoms in children (aged 4-17 years) with asthma. A national survey was conducted with parents of 516 children diagnosed with asthma or taking medications for asthma in the prior year. The majority of parents reported that their child experienced one or more exercise-related respiratory symptom and almost one-half (47.4%) experienced four or more symptoms. Most commonly reported symptoms were coughing, shortness of breath, and wheezing. Respondents reported that asthma limited their child's ability to participate either "a lot" or "some" in sports (30%), other outdoor activities (26.3%), and normal physical exertion (20.9%). Only 23.1% of children with exercise-related respiratory symptoms were reported to take short-acting beta-agonists such as albuterol "always" or "most of the time" before exercising. Exercise-related respiratory symptoms among pediatric asthma patients are common and substantially limit the ability of children to participate normally and perform optimally in physical activities. Such symptoms may reflect uncontrolled underlying asthma that should be evaluated and treated with appropriate controller medications. Despite the availability of preventative therapy, many children do not use short-acting bronchodilators before exercise as recommended in national guidelines.

Impact of exercise-related respiratory symptoms in adults with asthma: Exercise-Induced Bronchospasm Landmark National Survey.

An estimated 5-20% of the general population and up to 90% of people with asthma experience exercise-induced bronchospasm (EIB). The EIB Landmark Survey is the first comprehensive study on exercise-related respiratory symptoms in the United States. Two surveys were conducted: the first surveyed adults (≥18 years) in the general public and the second surveyed adults with asthma or taking medications for asthma in the prior year. Parameters assessed included exercise-related respiratory symptoms, activity levels, and short-acting beta-antagonist (SABA) use. In the general public survey (n = 1085), 8% were currently diagnosed with asthma. However, 29% reported experiencing one or more of six respiratory-related symptoms during or immediately after exercising. In the EIB in adult asthma survey (n = 1001), although >80% of adults experienced one or more of six exercise-related respiratory symptoms, only 30.6% reported a diagnosis of EIB. Almost one-half (45.6%) of adults with asthma reported that they avoid physical activities because of symptoms. Despite symptoms, only 22.2% of respondents took SABAs before exercise "always" or "most of the time"; 36.3% took rescue medications after or during exercise. Exercise-related respiratory symptoms limit physical activities and negatively impact daily lives. However, adults in the United States lack awareness of EIB. Although many subjects stated that their asthma symptoms limit their physical activity, few adhered to treatment guidelines by using SABAs appropriately before exercising. Findings from this survey support the need for better communication about the proper evaluation and management of EIB in the community and in asthma patients.

Gastroesophageal reflux disease and asthma.

PURPOSE OF REVIEW: Asthma and gastroesophageal reflux disease (GERD) are both common diseases, and hence they often coexist. However, the coexistence of asthma and GERD is far more frequent than chance association. There remains debate regarding the mechanism of this relationship and whether treatment of GERD improves asthma outcomes. RECENT FINDINGS: Recent data have confirmed the high prevalence of GERD among patients with asthma. Many asthmatic patients with GERD documented by pH probe do not have classic symptoms of GERD and are considered to have 'silent GERD'. On the basis of smaller trials with somewhat conflicting results regarding improved asthma control with treatment of GERD, consensus guidelines recommend a trial of GERD treatment for symptomatic asthmatic patients even without symptoms of GERD. Recently, a large multicenter trial demonstrated that the treatment of asymptomatic GERD with proton pump inhibitors did not improve asthma control in terms of pulmonary function, rate of asthma exacerbations, asthma-related quality of life, or asthma symptom frequency. SUMMARY: Asthmatic patients have more GERD than the general population. There is not a clear understanding of why this is true. Current guidelines recommend that physicians consider treating patients who have poorly controlled asthma for GERD, even without GERD symptoms. Recent data suggest that this is not a useful practice for mild-to-moderate asthmatic patients.

Current concepts in the diagnosis and management of exercise-induced bronchospasm.

Exercise-induced bronchospasm (EIB) is a common occurrence in individuals with asthma, though it can also affect individuals without asthma. It occurs frequently in athletes. Common symptoms include coughing, dyspnea, chest tightness, and wheezing; however, there can be a variety of more subtle symptoms. The differential diagnosis of EIB is broad and includes several pulmonary and cardiac disorders. During the initial evaluation, a complete history, physical examination, and spirometry should be performed. In most patients with EIB, the baseline spirometry is normal; therefore, bronchoprovocation testing is strongly recommended. Both pharmacologic and nonpharmacologic approaches are important in the treatment of EIB. Management of EIB on the sideline of athletic events requires preparation and immediate access to rescue inhalers.

Exercise-induced asthma.

PURPOSE OF REVIEW: Exercise has been recognized as a trigger of bronchospasm for centuries. However, there remains much debate regarding the mechanism of this response, nomenclature to describe it, optimal tests for diagnosis, and treatment options. There is a need to review recent findings in this area both for clinicians and to highlight areas in need of additional research. RECENT FINDINGS: Recent data have confirmed the high prevalence of exercise-induced bronchospasm among athletes and raise concern that many of these athletes may be unaware of this diagnosis. Variability in nomenclature, classification, and diagnostic testing methods continue to make comparisons among reported trials difficult. Both in-vitro and animal studies reveal a heterogeneous inflammatory response correlated with exercise-induced bronchospasm. This variability may underlie the variable response to pharmacotherapy. SUMMARY: Clinicians need to be alert to the nonspecific nature of exercise-induced symptoms and increase utilization of objective testing for accurate diagnosis. Future research is needed to better define the optimal diagnostic test or algorithm. Clinical outcome and translational studies should focus on more precise phenotyping of participants and include more global measures of inflammation.

The clinical utility of eucapnic voluntary hyperventilation testing for the diagnosis of exercise-induced bronchospasm.

BACKGROUND: Exercise-induced bronchospasm (EIB) is the acute, transient airway narrowing associated with exercise. Eucapnic voluntary hyperventilation (EVH) has been used to diagnose EIB in elite athletes and in research settings. The clinical utility of EVH in a general pulmonary practice has not previously been reported. Thus we sought to determine the utility and applicability of EVH testing in the clinical setting. METHODS: We retrospectively analyzed 178 EVH tests performed at the Ohio State University Medical Center. RESULTS: A total of 178 EVH studies were performed. Fifty patients (28%) were EIB-positive. A threshold of 60% of the predicted maximum voluntary ventilation (MVV) per minute was used as a criterion for an adequate EVH test. A majority of patients, 127 (71%), had adequate EVH tests. Females were less likely to achieve 60% MVV than males (80% vs. 55%; p = 0.002). Of the 51 patients with inadequate tests, 17 (33%) were EIB-positive; 16 of these 17 were female. Overall, EVH testing was diagnostic in 144 of 178 (81%) of patients tested. CONCLUSIONS: We present the first description of the clinical use of EVH testing for the diagnosis of EIB in a large pulmonary practice. EVH was diagnostic in a large majority of patients. EVH is an excellent and feasible modality to diagnose EIB in patients seen in a general pulmonary practice. Our data highlight the need for further studies regarding the appropriate minimum threshold minute ventilation for an EVH test and to explain potential mechanisms for seemingly different stimulus thresholds for bronchospasm in males versus females.

Approach to the diagnosis and management of suspected exercise-induced bronchoconstriction by primary care physicians.

BACKGROUND: Exercise-related respiratory symptoms in the diagnosis of exercise-induced bronchoconstriction (EIB) have poor predictive value. The aim of this study was to evaluate how athletes presenting with these symptoms are diagnosed and managed in primary care. METHODS: An electronic survey was distributed to a random selection of family practitioners in England. The survey was designed to assess the frequency with which family practitioners encounter adults with exercise-related respiratory symptoms and how they would approach diagnostic work-up and management. The survey also evaluated awareness of and access to diagnostic tests in this setting and general knowledge of prescribing asthma treatments to competitive athletes. RESULTS: 257 family practitioners completed the online survey. One-third of respondents indicated they encountered individuals with this problem at a frequency of more than one case per month. Over two-thirds of family practitioners chose investigation as an initial management strategy, while one-quarter would initiate treatment based on clinical information alone. PEFR pre- and post-exercise was the most commonly selected test for investigation (44%), followed by resting spirometry pre- and post-bronchodilator (35%). Short-acting beta2-agonists were the most frequently selected choice of treatment indicated by respondents (90%). CONCLUSION: Family practitioners encounter individuals with exercise-related respiratory symptoms commonly and although objective testing is often employed in diagnostic work-up, the tests most frequently utilised are not the most accurate for diagnosis of EIB. This diagnostic approach may be dictated by the reported lack of access to more precise testing methods, or may reflect a lack of dissemination or awareness of current evidence. Overall the findings have implications both for the management and hence welfare of athletes presenting with this problem to family practitioners and also for the competitive athletes requiring therapeutic use exemption.

Airway inflammation in exercise-induced bronchospasm occurring in athletes without asthma.

Exercise-induced bronchospasm (EIB) occurs in athletes with and without asthma. Studies have suggested an inflammatory basis for EIB in asthmatics; however whether inflammation plays a similar role in EIB in athletes without asthma remains unclear. Our objective was to determine whether there is evidence of an inflammatory basis for exercise-induced bronchospasm occurring in non-asthmatic athletes. Ninety-six athletes without asthma from varsity college teams underwent eucapnic voluntary hyperventilation testing. Sputum was induced from subjects with hypertonic saline inhalation post-eucapnic voluntary hyperventilation testing and was analyzed with enzyme-linked immunosorbent assays for IL-5, IL-8, IL-13, cysteinyl-leukotrienes, prostaglandin E2, histamine, leukotriene B4, and thromboxane B2. In addition, inflammatory (neutrophils, lymphocytes, eosinophils, and macrophages) and epithelial cell counts in sputum were recorded. Multivariate regression modeling showed a significant correlation between concentrations of select inflammatory mediators after eucapnic voluntary hyperventilation testing and severity of EIB. Means of the log-transformed concentrations of inflammatory mediators in EIB-positive athletes were significantly higher post-eucapnic voluntary hyperventilation than in EIB-negative athletes. Similar findings were not demonstrated with inflammatory cells. Concentrations of inflammatory mediators are higher in EIB-positive athletes than in EIB-negative athletes without asthma after eucapnic voluntary hyperventilation testing. The severity of EIB in our cohort also is significantly correlated with increased concentrations of select inflammatory mediators suggesting a potential inflammatory basis for EIB in athletes without asthma.

The prevalence of asthma in an NCAA Division I collegiate athletic program.

PURPOSE: To determine the prevalence of asthma among all varsity athletes in a large National Collegiate Athletic Association (NCAA) Division I program. METHODS: We retrospectively reviewed the medical records for all varsity athletes at The Ohio State University (OSU). Data were abstracted from patient charts that contained a Medical Health Questionnaire, annual physical examinations, and medical encounters by the OSU Sports Medicine staff. A diagnosis of asthma was defined by self-report of physician diagnosis as recorded in the medical record. RESULTS: Overall, 130 of 763 (17.0%) athletes had a diagnosis of asthma. Females (67/280 or 23.9%) had a significantly higher prevalence of asthma than males (63/483 or 13.0%) (p value = 0.001). There was no significant difference in the prevalence of asthma between high- and low-ventilation sports. (p value = 0.201). CONCLUSIONS: The prevalence of asthma among varsity athletes at The Ohio State University is 17.0%, which is significantly higher than the reported prevalence of asthma in the general United States population between 18 to 24 years of age. More females had asthma in our study population than males. These data will allow for future studies and development of focused screening programs of collegiate athletes.

Prevalence of exercise-induced bronchospasm in a cohort of varsity college athletes.

INTRODUCTION: Exercise-induced bronchospasm (EIB) occurs more commonly in elite athletes than in the general population. There have been relatively few prevalence studies examining EIB in college athletes despite studies which have shown significant morbidity from asthma attacks related to exercise occurring in athletes in this age group. None of the previous studies utilized eucapnic voluntary hyperpnea (EVH) testing, which is the currently recommended test to document EIB in Olympians. METHODS: Varsity athletes at The Ohio State University underwent EVH testing to assess for EIB. RESULTS: One hundred seven athletes from 22 sports participated. Forty-two of 107 athletes (39%) were EIB positive according to EVH results. Thirty-six of 42 EIB-positive athletes (86%) had no prior history of EIB or asthma. There were no significant differences in the prevalence of EIB according to sex of the athlete (P=0.65) or ventilation demands of the sport (P=0.64). Symptoms were not predictive of EIB (P=0.44). The prevalence of EIB was 36% in athletes with negative symptoms and 35% for those with positive symptoms. Athletes in high-ventilation sports were significantly more symptomatic (48%) than athletes in low-ventilation sports (25%) (P=0.02); however, there was no difference in the prevalence of EIB between the two groups (P=0.64). CONCLUSIONS: Varsity athletes show a high incidence of EIB when objectively diagnosed by a variety of pulmonary function criteria. Sex of the athlete or ventilation demands of the sport does not affect the prevalence of EIB. The use of symptoms to diagnose EIB is not predictive of whether athletes have objectively documented EIB. Empiric diagnosis and treatment of EIB on the basis of subjective symptoms alone may lead to an increased number of inaccurate diagnoses and increased morbidity.

Exercise-induced bronchoconstriction in athletes.

Exercise-induced bronchoconstriction (EIB) describes airway narrowing that occurs in association with exercise. EIB occurs in up to 90% of asthmatic patients and is estimated to occur in > 10% of the general population. Recent reviews have identified asthma as a risk factor for sudden death and have reported many deaths that have been attributed directly to EIB. We present a review of the literature related to EIB in athletes including sections discussing its pathogenesis, diagnosis, and treatment, and which athletes are most at risk for experiencing EIB.

Exercise-induced bronchoconstriction.

Exercise-induced bronchoconstriction (EIB) occurs commonly in patients with asthma but also can affect individuals without asthma. EIB is particularly common in populations of athletes. Common symptoms include cough, dyspnea, chest tightness, and wheezing; however, there can be a variety of more subtle symptoms. In this article, the clinical presentation of EIB as well as the diagnosis and treatment of EIB are outlined.

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.

Sex differences in asthma symptom profiles and control in the American Lung Association Asthma Clinical Research Centers.

OBJECTIVE: Important differences between men and women with asthma have been demonstrated, with women describing more symptoms and worse asthma-related quality of life (QOL) despite having similar or better pulmonary function. While current guidelines focus heavily on assessing asthma control, they lack information about whether sex-specific approaches to asthma assessment should be considered. We sought to determine if sex differences in asthma control or symptom profiles exist in the well-characterized population of participants in the American Lung Association Asthma Clinical Research Centers (ALA-ACRC) trials. METHODS: We reviewed baseline data from four trials published by the ALA-ACRC to evaluate individual item responses to three standardized asthma questionnaires: the Juniper Asthma Control Questionnaire (ACQ), the multi-attribute Asthma Symptom Utility Index (ASUI), and Juniper Mini Asthma Quality of Life Questionnaire (mini-AQLQ). RESULTS: In the poorly-controlled population, women reported similar overall asthma control (mean ACQ 1.9 vs. 1.8; p = 0.54), but were more likely to report specific symptoms such as nocturnal awakenings, activity limitations, and shortness of breath on individual item responses. Women reported worse asthma-related QOL on the mini-AQLQ (mean 4.5 vs. 4.9; p < 0.001) and more asthma-related symptoms with a lower mean score on the ASUI (0.73 vs. 0.77; p ≤ 0.0001) and were more likely to report feeling bothered by particular symptoms such as coughing, or environmental triggers. CONCLUSIONS: In participants with poorly-controlled asthma, women had outwardly similar asthma control, but had unique symptom profiles on detailed item analyses which were evident on evaluation of three standardized asthma questionnaires.