Cough in the Athlete: CHEST Guideline and Expert Panel Report

Recurrent Cough in the Elderly: A Forgotten Entity

INTRODUCTION

Recurrent cough is little researched in adults. We investigated the prevalence, risk factors, and consequences of recurrent cough, and compared the results to those of isolated chronic cough.

METHODS

Cross-sectional email survey in an elderly community-based population. Recurrent cough was defined as ≥ 3 cough episodes within one year (each lasting ≥ 1 week) and no current chronic cough. Isolated chronic cough was defined as current cough lasting ≥ 8 weeks and no recurrent cough.

RESULTS

The prevalence of recurrent cough was 3.8% among all respondents (n = 5983). Recurrent cough was associated with asthma (aOR 3.32 (95% CI 2.13-5.18)), chronic rhinosinusitis (2.91 (1.89-4.46)), family history of chronic cough (2.59 (1.88-3.56)), analgesic intolerance (2.13 (1.27-3.57)), male gender (1.92 (1.39-2.66)), gastro-esophageal reflux disease (1.73 (1.21-2.47)), obstructive sleep apnoea (1.69 (1.23-2.32)), symptom sum (1.12 per symptom (1.03-1.22)), and younger age (0.96 per year (0.93-1.00)). Isolated chronic cough was associated with chronic rhinosinusitis (3.45 (2.39-4.97)), asthma (2.17 (1.38-3.41), gastro-esophageal reflux disease (1.80 (1.32-2.47)), family history of chronic cough (1.80 (1.35-2.41)), obstructive sleep apnoea (1.49 (1.12-2.00)), symptom sum (1.18 per symptom (1.10-1.27)), and body mass index (0.96 per unit (0.93-1.00)). Among subjects with recurrent and isolated chronic cough, the prevalence of depressive symptoms were 7.7% and 4.2%, p = 0.11, the Leicester Cough Questionnaire total scores 15.2 (14.6-15.8) and 16.3 (16.0-16.6), P = 0.001, and the mean number of yearly cough-related doctor`s visits 0.58 (0.45-0.71) and 0.36 (0.19-0.53), P = 0.007, respectively.

CONCLUSION

The risk factors and consequences of recurrent and isolated chronic cough were comparable. Recurrent cough seems beneficial to address in cough evaluation.

Cross-country skiers often experience respiratory symptoms during and after exercise but have a low prevalence of prolonged cough

Background

Cross-country skiers train and compete during the winter for long periods of time in subfreezing conditions, which strains the airways and provokes respiratory symptoms. This study aimed to compare the prevalence of exercise-related symptoms and prolonged cough in competitive cross-country skiers versus the general population and to investigate the association between these symptoms and asthma.

Methods

A questionnaire was sent to Finnish cross-country skiers (n=1282) and a random sample of the general population (n=1754), with response rates of 26.9% and 19.0%, respectively.

Results

Both groups were mostly asymptomatic at rest, but symptoms were increased in both groups during and after exercise. Cough was more prevalent after exercise in skiers and phlegm production was more common during and after exercise in skiers. Asthma did not provoke specific symptoms, but symptom prevalence was higher in asthmatic individuals. Skiers had a higher prevalence of cough after exercise (60.6% vs 22.8%, p<0.001) compared with controls, but controls had a higher prevalence of prolonged cough (4.1% vs 9.6%, p=0.004). In participants without asthma, cold air triggered symptoms more often in skiers than controls, while strong odours triggered symptoms more often in asthmatic controls than skiers. Chronic cough lasting more than 8 weeks was rare, reported by 4.8% of controls and 2.0% of skiers.

Conclusion

Cross-country skiers, especially those with asthma, experience a higher burden of exercise-related respiratory symptoms compared with controls. However, repeated exposure to cold air does not appear to result in long-term hypersensitivity of the cough reflex arc.

Primary Care Considerations for the Baseball Athlete

PURPOSE OF REVIEW

To summarize current guidance and best practices surrounding non-orthopedic medical concerns in baseball.

RECENT FINDINGS

Discussion of COVID19-related practice changes pertaining to the prevention and screening of communicable respiratory illness, concussion protocol updates, the enhanced role of a multi-disciplinary team of mental health professionals. Prevention, appropriate screening, and early identification remain cornerstones of effective primary care both within the general population as well as for the baseball athlete.

Diagnosis and management of allergy and respiratory disorders in sport: An EAACI task force position paper

Allergy and respiratory disorders are common in young athletic individuals. In the context of elite sport, it is essential to secure an accurate diagnosis in order to optimize health and performance. It is also important, however, to consider the potential impact or consequences of these disorders, in recreationally active individuals engaging in structured exercise and/or physical activity to maintain health and well-being across the lifespan. This EAACI Task Force was therefore established, to develop an up-to-date, research-informed position paper, detailing the optimal approach to the diagnosis and management of common exercise-related allergic and respiratory conditions. The recommendations are informed by a multidisciplinary panel of experts including allergists, pulmonologists, physiologists and sports physicians. The report is structured as a concise, practically focussed document, incorporating diagnostic and treatment algorithms, to provide a source of reference to aid clinical decision-making. Throughout, we signpost relevant learning resources to consolidate knowledge and understanding and conclude by highlighting future research priorities and unmet needs.

Serum and sputum MMP-9/TIMP-1 in winter sports athletes and swimmers: relationships with airway function

INTRODUCTION

Skiers and swimmers present characteristics of airway inflammation and remodeling of the extracellular matrix similar to what is observed in mild asthma. We aimed to compare serum and sputum MMP-9/TIMP-1 levels, to assess the balance between airway fibrogenesis and inflammation process in both categories of athletes, and to observe its seasonal variations in winter sports athletes.

METHODS

We conducted a retrospective study. Winter sports athletes (n = 41), swimmers (n = 25) and healthy nonathletes (n = 10) had blood sampling, lung function measurement, skin prick tests, eucapnic voluntary hyperpnea challenge, methacholine inhalation test, and induced sputum analysis. Twelve winter sport athletes performed the tests during both summer and winter. Serum and sputum biomarkers were measured by ELISA.

RESULTS

No significant difference in serum or sputum MMP-9/TIMP-1 ratio was observed between groups, nor relationship with airway function or responsiveness. Serum MMP-9/TIMP-1 ratio was higher during the summer in winter sport athletes compared with winter season (median [Interquartile range]: 3.65 [2.47-4.03] ng.ml^-1 and 1.27 [0.97-1.62] ng.ml^-1, respectively, p = 0.005). Sputum MMP-9 correlated with methacholine PC₂₀ (r = 0.45, p = 0.019) and serum cc16/SP-D ratio (r=-0.47, p = 0.013).

CONCLUSION

MMP-9/TIMP-1 ratio in sputum or serum may fluctuate with training or environment but does not correlate with airway function or responsiveness in athletes.

The interest of rehabilitation of respiratory disorders in athletes: Myth or reality?

BACKGROUND

Healthy trained athletes generally have an "overbuilt" respiratory system in order to face the huge ventilation and gas-exchange demand imposed by strenuous exercise. Athletes frequently complain of respiratory symptoms regardless of whether they have a diagnosed respiratory disease, therefore evoking a kind of respiratory limitation during exercise. Some respiratory pathologies athletes present are closely linked to exercise and include asthma, exercise-induced bronchoconstriction (EIB) or exercise-induced laryngeal obstruction. Management of asthma and EIB are mainly based on pharmacological treatments. However, many athletes still complain of respiratory symptoms despite optimal pharmacological treatments, which highlights the need for non-pharmacological approaches including breathing retraining, inspiratory muscle training and/or laryngeal exercise performed under the guidance of a physiotherapist in this specific population.

OBJECTIVES

With this literature overview, we aimed to report evidence supporting the interest of rehabilitation for athletes with respiratory disorders and discuss whether inspiratory muscle training programs can improve performance in healthy athletes.

METHODS

We searched MEDLINE and Cochrane databases for trials, reviews and meta-analyses assessing respiratory rehabilitation and muscle training programs in athletes by using the MesH terms "athletes", "asthma", "dyspnea", "rehabilitation" and "education" published from January 2010 to March 2020. The selection of articles was based on the author's expertise to elaborate this review of the literature.

RESULTS

Major findings suggest that breathing retraining may help asthmatic athletes better control their respiratory symptoms and that inspiratory muscle training may improve respiratory symptoms of exercise-induced laryngeal obstruction in athletes. Improvement of performance by respiratory muscle training still remains controversial.

CONCLUSIONS

Respiratory rehabilitation could be of interest in the specific population of athletes but should be further evaluated to improve the level of evidence of such strategies.

Are Respiratory Responses to Cold Air Exercise Different in Females Compared to Males? Implications for Exercise in Cold Air Environments

Research has shown that cold air exercise causes significant respiratory dysfunction, especially in female athletes. However, how female and male athletes respond to cold air exercise is not known. Thus, we aimed to compare acute respiratory responses (function, recovery and symptoms) in males and females after high-intensity cold air exercise. Eighteen (nine female) athletes completed two environmental chamber running trials at 0 °C and −20 °C (humidity 34 ± 5%) on different days in a randomized starting order. Spirometry was performed pre, 3, 6, 10, 15 and 20 min post. Respiratory symptoms were measured posttrial and heart rate and rating of perceived exertion were assessed during each trial. No significant differences in delta change (pre to post) were found at either temperature between sexes for FEV₁, FVC, FEF50% and FEF25–75%. At −20 °C, FEV₁ decreased similarly in both sexes (males: 7.5%, females: 6.3%) but not at 0 °C, p = 0.003. Postexertion respiratory function recovery and reported symptoms were not different between sexes at either temperature. These results indicate no sex-based differences in acute respiratory responses (function, recovery and symptoms) to cold air exercise. However, intense exercise at −20 °C is challenging to the respiratory system in both sexes and may lead to altered respiratory responses compared to mild winter conditions like 0 °C.

Desensitization of the Cough Reflex Induced by Corticosteroids in Ovalbumin-Sensitized Rabbits During Artificial Limb Exercise

Introduction

Cough is a major symptom frequently experienced during exercise, mainly in asthmatic patients. Inhaled glucocorticoids represent the keystone treatment in the management of asthma, but little is known about interactions between cough and exercise, especially in controlled patients. During exercise, cough reflex (CR) appears downregulated in healthy animal models whereas a lack of desensitization of CR has been shown in ovalbumin-sensitized animal models, mimicking asthmatic disease.

Aims and Objectives

The goal of our study was to clarify the potential modulation of the CR induced by inhaled corticosteroids (CS) in ovalbumin (OVA) sensitized rabbits during artificial limb exercise.

Materials and Methods

Seventeen OVA sensitized rabbits were studied. Among them, 9 were treated with CS delivered intravenously (OVA-Corticoids). The ventilatory response to direct tracheal stimulation, performed at rest and during exercise, was determined to assess the incidence and the sensitivity of the CR. Broncho-alveolar lavage (BAL) and cell counts were performed to determine the level of airway inflammation. Exercise was mimicked by electrically induced hindlimb muscular contractions (EMC).

Results

Compared to rest values, EMC increased minute ventilation by 28% without any decrease in respiratory resistance (Rsr). Among 322 tracheal stimulations, 172 (53%) were performed at rest and 150 (47%) during exercise. The sensitivity of CR decreased during artificial limb exercise compared to baseline in OVA-Corticoids rabbits (p = 0.0313) while it remained unchanged in OVA rabbits (p = NS).

Conclusion

Corticosteroids appear to restore the desensitization of the CR in OVA sensitized rabbits during artificial limb exercise, suggesting the potential role of airway inflammation in the pathophysiology of cough during exercise in asthmatics.

Chronic cough in Vocal Cord Dysfunction: Description of a clinical entity

BACKGROUND AND AIM

Vocal Cord Dysfunction (VCD) and chronic cough (CC) are challenging conditions which lead to significant quality of life impairment. The underlying mechanisms are poorly understood, but laryngeal dysfunction may be common to both conditions. The aim of this study was to determine the characteristics of cough in VCD and whether patients with cough have coexisting VCD.

METHOD

Participants included 51 patients with VCD and a comparison group of 39 patients with chronic cough that was refractory to medical treatment. Participants underwent a comprehensive assessment including questionnaires, laryngoscopy, cough frequency monitoring and voice testing.

RESULTS

Patients with VCD had significant cough morbidity with an increased cough frequency of 17.3 coughs/hour and reduced cough quality of life with mean Leicester Cough Questionnaire Score of 12.8. Breathing pattern abnormalities were also common in VCD and there was a strong correlation between the number of breathing pattern abnormalities and cough frequency (r = -0.827, p = 0.002). Cough measures were not significantly different between patients with VCD and those with CC. Moderate-severe PVFM was present in 69% of patients with CC. Abnormal vocal fold closure during phonation was also present in patients with chronic cough and was similar between the VCD (n = 40, 78.4%) and cough (n = 25, 64.1%) groups, p = 0.240.

CONCLUSION

Cough is an important symptom in VCD. Patients presenting with chronic cough may have underlying VCD as a cause of their cough. Since cough and VCD symptoms co-occur clinicians need to consider cough when are treating VCD and VCD when treating chronic cough.

Sports and Infections

Acute infectious diseases are frequent among athletes and can result in training and competition absence. Since athletes are expected to return to training as soon as possible, the knowledge of these diseases, their clinical presentation, possible complications, transmission mechanisms, and prevention should be among the main concerns of sports medicine. Infectious diseases can be prolonged or aggravated by continuing physical activity and athletes also risk having other acute or chronic organ manifestations such as bronchitis or pneumonia, myocarditis, pericarditis, and other secondary complications, for this reason exercise should not be allowed during convalescence and recovery. In the case of elite athletes, the return-to-play decision is particularly important and consensus between scientific evidence and clinical experience is necessary. Although infectious diseases are highly prevalent in athletes, there is a scarcity of literature focused on evidence and guidelines for sports physicians regarding RTP decision. Each case should be individualized according to subjective and objective symptoms together with the patient’s progress in every particular case.

Cough in exercise and athletes

In the general population, particularly in individuals with asthma, cough is a common symptom, often reported after exertion, although regular exercise may be associated with a reduction in the prevalence of cough. In athletes, exercise-induced cough is also a particularly frequent symptom. The main etiologies of cough in athletes are somewhat similar to non-athletes, including asthma/airway hyperresponsiveness, upper airways disorders such as allergic or non-allergic rhinitis, and exercise-induced laryngeal obstruction, although these conditions are more frequently observed in athletes. In these last, this symptom can also be related to the high ventilation and heat exchange experienced during exercise, particularly during exposure to cold/dry air or pollutants. However, gastroesophageal reflux, a common cause of cough in the general population, despite being highly prevalent in athletes, has not been reported as a main cause of cough in athletes. Cough may impair quality of life, sleep and exercise performance in the general population and probably also in athletes, although there are few data on this. The causes of cough should be documented through a systematic evaluation, the treatment adapted according to identified or most probable cough etiology and pattern of presentation, while respecting sports anti-doping regulations. More research is needed on exercise-induced persistent cough in the athlete to determine its pathophysiology, optimal management and consequences.

Managing patients with chronic cough: challenges and solutions

Chronic cough is a common complaint and a frequent cause of medical consultation. Its management can be difficult. We present here an overview of the current guidelines for the management of chronic cough. Different steps are detailed, including the initial research of an obvious etiology and alert signs that should lead to further investigation of underlying condition. The diagnosis of the most frequent causes: asthma, non-asthmatic eosinophilic bronchitis, gastroesophageal reflux disease and upper airway cough syndrome should be considered, assessed and treated accordingly. Recent advances have been made in the comprehension of refractory chronic cough pathophysiology as well as its pharmacologic and non-pharmacologic treatment, especially speech pathology therapy.

Cough reflex sensitivity after exercise challenge testing in children with asthma

Bronchial challenge tests are commonly used in clinical medicine and research. The aim of this study was to clarify changes of cough reflex sensitivity before and after exercise challenge testing in asthma children. 42 asthmatic children were submitted to cough reflex sensitivity measurement - capsaicin aerosol in doubling concentrations (from 0.61 to 1250 micromol/l) was inhaled by a single breath method - before and after exercise challenge testing. Concentrations of capsaicin causing two (C2) and five coughs (C5) were reported. Children' (31 boys and 11 girls, mean age 14.05 ± 2.08 yrs) cough reflex sensitivity (median, with the 95% CI) for C2 was before exercise challenge testing 9.77 (6.10-10.99) micromol/l vs. children' C2 after it 7.32 (6.10-14.65) (P = 0.58 for the Wilcoxon two sample paired test). Children' C5 was before exercise challenge testing 19.53 (14.65-80.57) micromol/l vs. C5 after it 39.06 (24.42-58.59) micromol/l (P = 0.09 for the Wilcoxon two sample paired test). We conclude that cough reflex sensitivity was not significantly changed after exercise challenge testing in children with asthma.

Down-Regulation of Cough during Exercise Is Less Frequent in Healthy Children than Adults. Role of the Development and/or Atopy?

Cough is typically associated with physical activity in children with asthma, but the characteristics of the relationship between cough and exercise has not been established under physiological conditions. The aim of the study was to describe the effect of exercise on the reflex cough response elicited by a single breath of capsaicin in non-asthmatic children. A group of non-asthmatic adults was studied as reference. Thirty children and 29 adults were recruited. The cough reflex sensitivity to capsaicin was first determined to establish the dose that provokes 5 cough efforts (C5). The number of coughs elicited by C5 (NC5) was then compared at baseline and during a standardized submaximal treadmill exercise. Data are expressed as median (interquartile range). Children and adults showed a significant decrease in NC5 (respectively from 5.0 (4.0–6.0) to 2.5 (2.0–4.0), p < 0.0005 and from 6.0 (5.0–7.0) to 2.0 (0.0–3.0, p < 0.0005). During exercise, NC5 was observed to decrease in all adult subjects, but in only 24/30 children (80%, p = 0.02). A trend for a higher incidence of personal and familial atopy was observed in children that lacked cough down-regulation during exercise compared with other children. It is concluded that the cough reflex response to capsaicin is down regulated by exercise in both children and adults. The effect however is less consistently observed in the former. The difference may reflect maturation of descending inhibitory pathways of the cough reflex, but may also be associated to atopy. The data stress the importance of assessing the time relationship of cough and exercise in questionnaire studies of asthma.

Cough in exercise and athletes

Cough is the most common respiratory symptom reported by athletes and can significantly impact on health status, ability to train and athletic performance. The presence of cough in an athlete is typically taken to indicate exercise-induced bronchoconstriction (EIB), yet in many athletes with chronic cough there is no objective evidence of airway hyper-responsiveness (AHR) or heightened airway inflammation. Moreover, cough in athletes often fails to respond to a therapeutic asthma strategy, thus further work is urgently needed to progress our understanding of the pathophysiology of exercise-associated cough in this unique population. This article provides an overview of the current state of knowledge of exercise-associated cough in athletes. The article summarises our understanding of pathophysiological basis of cough in this context and provides a pragmatic clinical approach to this problem.