Jonathan P. Parsons

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.

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.

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.

The relationship between gastroesophageal reflux and asthma: an update

Asthma and gastroesophageal reflux disease (GERD) are both common conditions and, hence, they often coexist. However, asthmatics have been found to have a much greater prevalence of GERD symptoms than the general population. There remains debate regarding the underlying physiologic mechanism(s) of this relationship and whether treatment of GERD actually translates into improved asthma outcomes. Based on smaller trials with somewhat conflicting results regarding improved asthma control with treatment of GERD, current guidelines recommend a trial of GERD treatment for symptomatic asthmatics even without symptoms of GERD. However, 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. These data suggest empiric treatment of asymptomatic GERD in asthmatics is not a useful practice. This review article provides an overview of the epidemiology and pathophysiologic relationships between asthma and GERD as well as a summary of current data regarding links between treatment of GERD with asthma outcomes.

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

BackgroundExercise-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.MethodsAn 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.Results257 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 β2-agonists were the most frequently selected choice of treatment indicated by respondents (90%).ConclusionFamily 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.

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.

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 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.

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.

Etiology of Dyspnea in Elite and Recreational Athletes

Abstract 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 centers 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.