Exercise-induced Asthma Research Articles

EFFECT OF PHYSICAL TRAINING ON EXERCISE-INDUCED BRONCHOSPASM IN YOUNG ASTHMATICS

ABSTRACT Introduction: Asthma is the most common chronic disease in childhood and its prevalence has increased in recent years. Although regular physical activity (PA) is considered to be beneficial for the health of asthmatics, especially children and adolescents, it can also be one of the elements that triggers asthma. This is known as exercise-induced bronchospasm (EIB), and is considered one of the factors that limits asthmatics’ participation in PA. Objective: This study aims to review the effects of physical conditioning on EIB in asthmatic children and adolescents. Methods: A systematic review was carried out on the Pubmed, Bireme and Web of Science databases, considering publications from 1998 to April 2019. Results: Eight articles were retrieved; five of the articles presented no significant difference in EIB parameters after physical training, and three demonstrated significant benefits in EIB. Conclusion: There is insufficient evidence that physical training helps reduce the frequency and severity of EIB in young asthmatics. There are still few studies that seek to show the effect of a physical training program on the improvement of EIB in children and adolescents. It is suggested that further randomized clinical trials be conducted, to investigate the effects of physical training on EIB parameters in children and adolescents. Level of Evidence II; Systematic review.

Special Considerations and Perspectives for Exercise-Induced Bronchoconstriction (EIB) in Olympic and Other Elite Athletes

Diagnosing and treating elite and Olympic athletes with exercise-induced bronchoconstriction has been well established. However, a subset of elite and Olympic athletes with exercise-induced bronchoconstriction experience symptoms of breathlessness due to lack of adherence, improper medications, and/or generalized breathing dysfunction. A short review of traditional treatment plans for elite and Olympic athletes is presented along with the challenges of adherence, managing dysfunctional breathing, and measuring and treating mental skills deficits that may impact breathing. Elite and Olympic athletes may not respond to traditional treatment for exercise-induced bronchospasm, and we present some of the reasons why the athletes fail to respond. Furthermore, we present information on how to detect and treat elite and Olympic athletes with difficult-to-treat asthma. As part of this review we developed a flow diagram for medical providers to identify the reasons for lack of response to traditional treatment plans for exercise-induced bronchoconstriction with options for other treatment modalities.

Determinants of severe exercise-induced bronchoconstriction in Nigerian children with asthma.

Asthmatics with severe exercise-induced bronchoconstriction (EIB) are at high risk of exacerbations. The purpose of this study was to determine the prevalence, phenotypic, and laboratory determinants of severe EIB in Nigerian children with asthma. Children with controlled asthma (n = 101) underwent characterization and free-running exercise bronchoprovocation at a center in Nigeria. Lung function was measured before, then 5, 10, 15, and 30 minutes after 6 to 8 minutes exercise. Severe EIB was defined as ≥50% decrease in forced expired volume in 1 second (FEV1 ) from preexercise. Serum vitamin D and total antioxidant capacity were measured chromatographically. Factors predicting severe EIB were tested by logistic regression. The sample was enriched in children with corticosteroid-naïve, mild intermittent asthma (71%). Thirteen percent had no EIB, 22% had severe and 65% nonsevere EIB. Children with severe EIB had higher preexercise FVC (105% vs 96%; P = .03) and FEV1 (98% vs 90%; P = .07), greater obesity (13.6% vs 1.3%; P = .02), more allergic rhinitis (AR) (63.6% vs 35.4%; P = .03), but less exposure to household pets (31.8% vs 72.2%; P = .003) compared to children with nonsevere EIB. Significant determinants (odds ratios/confidence intervals) for severe EIB were obesity = 12.3 (1.2-125.1), AR = 3.18 (1.19-8.52), blood eosinophilia = 1.005 (1.001-1.009), and hypovitaminosis D = 0.87 (0.81-0.93). In Nigerian children with asthma, severe EIB is common and associated with remediable comorbidities including type 2 pattern inflammation and vitamin D deficiency.

Can Pediatricians Assess Exercise-Induced Bronchoconstriction From Post-exercise Videos?

Objective: Exercise-induced bronchoconstriction (EIB) is a highly prevalent morbidity of childhood asthma and defined by a transient narrowing of the airways during or after physical exercise. An exercise challenge test (ECT) is the reference standard for the diagnosis of EIB. Video evaluation of EIB symptoms could be a practical alternative for the assessment of EIB. We studied the ability of pediatricians to assess EIB from post-exercise videos.Methods: A clinical assessment was performed in 20 asthmatic children (mean age 11.6 years) and EIB was measured with a standardized ECT performed in cold, dry air. EIB was defined as a fall in forced expiratory volume in 1 s (FEV1) of ≥10% post-exercise. Children were filmed before and after exercise in frontal position and bare chested. The clinical assessment results and videos were shown to 20 pediatricians (mean experience 14.4 years). Each assessed EIB severity in 5 random children providing 100 assessments, scored on a continuous rating scale (0–10) and in severity classifications (no, mild, moderate, severe) using a scoring list including physical asthma symptoms. Correlations between predicted scores and objective scores were calculated with Spearman's rho and Cohen's Kappa. A generalized linear model was used to assess the relationship between physical symptoms and fall in FEV1.Results: Median fall in FEV1 after exercise was 15.1% (IQR 1.2–65.1). Pediatricians detected EIB with a sensitivity of 78% (95% CI 66–87%) and a specificity of 40% (95% CI 27–55%). The positive predictive value for a pediatricians' diagnosis of EIB was 61% (95% CI 50–72%). The negative predictive value was 60% (95% CI 42–76%). The agreement between predicted EIB severity classifications and the validated classifications based on the ECT's, was fair [Kappa = 0.36 (95% CI 0.23–0.48)]. The correlation between predicted EIB severity scored on a continuous rating scale and fall in FEV1 after exercise was weak (rs = 0.39, p < 0.001). Independent predictive variables for fall in FEV1 were wheezing (−11%), supraclavicular retractions (−8.4%) and a prolonged expiratory phase (−8.8%).Conclusion: The ability of pediatricians to assess EIB from post-exercise videos is fair at best, implicating that standardized ECT's are still vital in the assessment of EIB.

Exercise-induced bronchospasm and its associated factors among secondary school students in an urban community

ABSTRACT Introduction: Exercise-induced bronchospasm (EIB) is a transient narrowing of the airway that usually occurs shortly after exercise. It occurs commonly in people with asthma; however EIB has also been reported in individuals without clinical asthma. The study aimed to determine the prevalence and factors associated with EIB among secondary school students. Methods: It was a descriptive cross-sectional school- based study involving secondary school students aged between 10 and 17 years without previous history of asthma. Subjects undertook a six-minute running test, spirometry was done and the best of three FEV1 readings were obtained pre-exercise, at 5, 10, 15 and 30 minutes post exercise. The diagnosis of EIB was made when there was a decrease in FEV1 of ≥10% from baseline after exercise. Results: Of the 265participants studied, 34 (12.8%) had EIB at 5 minutes post exercise. EIB was significantly more in the 10–13 years age group (χ2 = 18.416, p = <0.001), there was no significant gender difference. The presence of allergic (vernal) conjunctivitis and rhinitis were both significantly associated with the development of EIB (χ2 = 13.574, p < 0.001 and 0.011 respectively). There was no significant association with previous history of wheeze and exposure to indoor air pollution such as cooking with biomass fuel and parental cigarette smoking. Conclusion: EIB exist among non-asthmatic school children, and it is more frequent in the early adolescent age-group. Students with allergic conjunctivitis and rhinitis are more likely to manifest exercise induced bronchospasm.

Astma kod vrhunskih sportista; mehanizam nastanka i uticaj na disajnu funkciju - pregled literature

Introduction: It is generally accepted that physical activity benefits every person but athletes diagnosed with asthma face various challenges during their training to keep the symptoms of the disease under control. Prolonged exposure to agents in the environment in which athletes train favors the development of permanent changes in the airways. Their action leads to permanent hyper-reactivity with development of an inflammatory response and the release of mediators (IL-8, leukotrienes, eicosanoids) that lead to damage epithelial cells with breaking connection between them and consequent dysfunction of the respiratory system. This condition is called exercise-induced asthma (EIA). This fact is especially important for athletes who have long endurance training. The best way to check the condition of breathing system is with a diagnostic method which is the " gold" standard spirometry. Aim: The point of this systematic review is to get closer the mechanism occurrence of EIA/(exercise-induced bronchoconstriction)-EIB, prevalence and incidence of EIA/EIB, changes of pulmonary function and quality of life in elite athletes. We searched papers from PubMed and Cochrane database using keywords: 'exercise-induced asthma', 'athletes', 'spirometry', 'bronchoconstriction', 'bronchospasm', 'physical activity', 'physical training', 'prevalence', 'incidence'. We have studied 48 scientific papers in total. Conclusion: The prevalence of asthma among elite athletes, especially endurance athletes is higher than in general population. The explanation of this phenomenon is related to the whole mechanism of occurrence, it is still insufficiently clarified, but one thing is for sure that with good disease control athletes can play and compete undisturbed for many years.

Associations between obesity, asthma and physical activity in children and adolescents

Abstract Obesity and asthma have increased in prevalence dramatically among children and adolescents. There is strong epidemiological evidence of an association between these chronic morbidities, suggesting many pathophysiological pathways which may play a role in this association such as adipokines, oxidative stress, physical activity, comorbidities and diet. Physical activity and exercise are recommended to reduce obesity and the risk of several diseases. However, exercise is a common trigger of asthma, known as exercise-induced bronchoconstriction. Similarly, obesity-related physical deconditioning may also lead to dyspnoea and exercise limitation which can mimic asthma symptoms. Furthermore, to confirm that excessive weight is a risque factor for asthma, the evidence of causality must establish whether weight loss should decrease in asthma symptoms. The purpose of this review is to summarize what is known about the complex relationship between obesity, asthma and physical activity.

Exercise-Induced Bronchoconstriction in Iraq and Afghanistan Veterans With Deployment-Related Exposures.

Acute exposure to high-levels of ambient fine particulate matter while exercising results in airway narrowing, but the long-term effects of repeated exposure on exercise-induced bronchoconstriction (EIB) are not well known. The goal of this preliminary study is to determine the rate of EIB among a sample of non-treatment seeking veterans deployed to Iraq and Afghanistan. Twenty-four veterans (median [interquartile range]: 35.0 [27.3, 45] years) without history of asthma volunteered for this study. Spirometry was assessed before and after a standardized exercise challenge. A positive EIB response was defined as an exercise-induced fall in forced expiatory volume in 1second ≥10%. Secondary criteria (peak flow ≥10% or mid-expiratory flow ≥15%) were also considered as an estimate of probable EIB. A positive EIB response was observed in 16.7% and probable EIB response was observed in 41.7% of our sample. Median deployment length to Iraq or Afghanistan was 13.0 [10.3, 17.5] months and the median time since deployment was 4.2 [2.7, 7.7] years. At the time of testing, veterans reported persistent cough (58.3%), wheeze (37.5%), and shortness of breath (37.5%). During deployment, veterans reported exposure to dust and sand (70.8%), smoke from burn pits (66.7%), vehicle exhaust (83.3%), and regional air pollution (26.0%) on most days or daily. Approximately 17% of our sample of non-treatment seeking deployed Iraq and Afghanistan veterans demonstrated EIB, similar to the general population prevalence. However, persistent respiratory symptoms and alternative indices of probable EIB supports continued monitoring of this population.

Effects of a heat and moisture exchanger on respiratory function and symptoms post-cold air exercise.

PurposeExercise at temperatures below −15°C induces drying and cooling of lung airways which causes exercise‐induced bronchoconstriction (EIB) and respiratory symptoms, especially in winter sport athletes. The objective of this study was to evaluate whether a heat and moisture exchanger (HME) worn during intense cold air exercise improves lung function and reduces respiratory symptoms in healthy winter sport athletes.MethodsSeven active males and six active females (maximum oxygen uptake 61.9 ± 6.9 and 52.2 ± 5.3 mL/kg/min), all active or former winter sport athletes, completed running trials with and without HME in random order on 2 days in an environmental chamber (−20°C temperature, humidity 46.2%). Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory flow at 25%‐75% (FEF25%‐75%), and FEF at 50% (FEF50%) were measured pre‐ and post‐exercise (3, 6, 10, 15, and 20 minutes). Respiratory symptoms were reported after exercise.ResultsSignificant interaction effects were observed for FEV1 and FEF25%‐75%. Mean decrease of FVC (−5.9%, P ≤ .001) and FEV1 (−4.2%, P = .003) was largest 3 minutes post‐exercise without HME. There was an increase of FEV1, FEF25%‐75%, and FEF50% post‐exercise compared to pre‐exercise with HME. More respiratory symptoms overall were reported without HME (P = .046).ConclusionIntense cold air exercise likely causes transient acute bronchoconstriction and symptoms of cough in individuals participating in winter sports. However, this study finds that the application of an HME during intense cold air exercise improves lung function and reduces prevalence of EIB‐associated symptoms compared to unprotected intense cold air exercise.

Many continuous variables should be analyzed using the relative scale: a case study of \u03b22-agonists for preventing exercise-induced bronchoconstriction

BackgroundThe relative scale adjusts for baseline variability and therefore may lead to findings that can be generalized more widely. It is routinely used for the analysis of binary outcomes but only rarely for continuous outcomes. Our objective was to compare relative vs absolute scale pooled outcomes using data from a recently published Cochrane systematic review that reported only absolute effects of inhaled β2-agonists on exercise-induced decline in forced-expiratory volumes in 1 s (FEV1).MethodsFrom the Cochrane review, we selected placebo-controlled cross-over studies that reported individual participant data (IPD). Reversal in FEV1 decline after exercise was modeled as a mean uniform percentage point (pp) change (absolute effect) or average percent change (relative effect) using either intercept-only or slope-only, respectively, linear mixed-effect models. We also calculated the pooled relative effect estimates using standard random-effects, inverse-variance-weighting meta-analysis using study-level mean effects.ResultsFourteen studies with 187 participants were identified for the IPD analysis. On the absolute scale, β2-agonists decreased the exercise-induced FEV1 decline by 28 pp., and on the relative scale, they decreased the FEV1 decline by 90%. The fit of the statistical model was significantly better with the relative 90% estimate compared with the absolute 28 pp. estimate. Furthermore, the median residuals (5.8 vs. 10.8 pp) were substantially smaller in the relative effect model than in the absolute effect model. Using standard study-level meta-analysis of the same 14 studies, β2-agonists reduced exercise-induced FEV1 decline on the relative scale by a similar amount: 83% or 90%, depending on the method of calculating the relative effect.ConclusionsCompared with the absolute scale, the relative scale captures more effectively the variation in the effects of β2-agonists on exercise-induced FEV1-declines. The absolute scale has been used in the analysis of FEV1 changes and may have led to sub-optimal statistical analysis in some cases. The choice between the absolute and relative scale should be determined based on biological reasoning and empirical testing to identify the scale that leads to lower heterogeneity.

Exercise-Induced Bronchoconstriction Identified Using the Forced Oscillation Technique.

Objective: Lung mechanics using the forced oscillation technique (FOT) is suggested to be equivalent and more sensitive in determining exercise-induced bronchoconstriction (EIB) than spirometry. Dynamic alterations in minute ventilation (VE) may affect this measurement. We investigated changes in FOT parameters post exercise challenge (EC) in people with asthma as compared to spirometry. The rate of recovery and any effect of raised VE following exercise on FOT parameters were also assessed.Method: Airway resistance (R5) and reactance (X5) at 5 Hz and VE were measured prior to forced expiratory volume in 1 s (FEV1) before and up to 20 min after a standard EC in people with asthma and healthy controls. Airway hyperresponsiveness to the hyperosmolar mannitol test was measured in the asthmatic subjects within 1 week of the EC. Baseline and sequential measures were assessed using repeated measures ANOVA and Pearson’s correlation. Group demographics and recovery data were compared using an unpaired t test.Results: Subjects with current asthma (n = 19, mean ± SD age 28 ± 6 years) and controls (n = 10, 31 ± 5 years) were studied. Baseline FEV1, R5, X5, and VE were similar between groups (p > 0.09). Airway hyperresponsiveness was present in 12/19 asthmatic subjects. The EC max % change of R5 and X5 correlated with FEV1 (r > 0.90) and were only different to controls in those with asthma that responded by FEV1 criteria (p < 0.01). EC recovery of R5 was similar to FEV1; however, X5 was greater (p = 0.03). Elevated VE post EC did not affect the % change in FOT parameters across all subjects (p > 0.3). R5 and X5 were highly sensitive in determining a positive EC response (80–86%), but X5 was more specific (93 vs. 80%).Conclusion: FOT parameters tracked with forced maneuvers and were not influenced by increased ventilation following an exercise challenge designed to elicit EIB. FOT identified EIB similarly to spirometry in patients with asthma.

Clinical Characterization and Predictors of IOS-Defined Small-Airway Dysfunction in Asthma

The involvement of small airways has recently gained greater recognition in asthma. Impulse oscillometry (IOS) is a simple and noninvasive method based on the forced oscillation technique, for the detection of small-airway dysfunction (SAD). To identify the predictors of SAD in an unselected sample of 400 patients with physician-diagnosed asthma. All patients underwent standard spirometry and IOS at the first visit, and were stratified by the presence of SAD defined by IOS (fall in resistance from 5 to 20 Hz [R5-R20] > 0.07 kPa× s× L-1). Univariable and multivariable analyses and classification tree method were used to analyze cross-sectional relationships between clinical variables and outcome (SAD). SAD was present in 62% of the cohort. Subjects with SAD showed a less well-controlled asthma, according to the Global Initiative for Asthma definition, and a higher mean inhaled corticosteroid dosage use compared with subjects without SAD (both P < .001). Increased fractional exhaled nitric oxide (odds ratio [OR], 2.05; 95% CI, 1.14-3.70), female sex (OR, 2.27; 95% CI, 1.29-4.06), smoking (OR, 3.06; 95% CI, 1.60-6.05), older age (OR, 3.08; 95% CI, 1.77-5.49), asthma-related night awakenings (OR, 3.34; 95% CI, 1.85-6.17), overweight (OR, 3.64; 95% CI, 1.99-6.85), and exercise-induced asthma symptoms (OR, 6.39; 95% CI 3.65-11.45) were independent predictors of SAD. Classification tree analysis confirmed that exercise-induced asthma, overweight, asthma-related night awakenings, smoking, and older age have potential for clinical use in distinguishing patients with SAD from those without it. We identified predictors of SAD and showed that especially exercise-induced asthma, overweight, asthma-related night awakenings, smoking, and older age were strongly associated with SAD.

Exhaled TGF-β1 levels before and after an exercise challenge in asthmatic and healthy children, and during exacerbation

Background There is conflicting data regarding the role of transforming growth factor-β1 (TGF-β1) in the pathogenesis of airway hyper-reactivity and asthma exacerbation. Objective To investigate the role of exhaled-TGF-β1 in exercise-induced bronchospasm (EIB) in asthmatic and nonasthmatic healthy children, and in asthma exacerbation and asthma control. Methods The exhaled-TGF-β1 levels of 56 stable asthmatic children and 15 nonasthmatic healthy children were evaluated before and 30 min after an exercise challenge. The exhaled-TGF-β1 levels of 20 additional children with asthma exacerbation were evaluated. Results While no significant difference in the exhaled-TGF-β1 levels was found at the baseline, exhaled-TGF-β1 levels after the exercise challenge were significantly higher in the non-EIB (n = 31) asthmatics when compared to the asthmatic children with EIB (n = 25) (p = 0.04). Although there was a statistically significant increase in the concentration of the exhaled-TGF-β1 after the exercise challenge in the non-EIB asthmatics (p = 0.008), the concentration of the TGF-β1 was not increased after the exercise challenge in EIB + asthmatics. The exhaled-TGF-β1 was significantly correlated with the ACT score (p = 0.01, r = 0.49) and the baseline FEV1 level (p = 0.02, r = 0.35). The exhaled-TGF-β1 levels were significantly higher in the stable asthmatic children when compared to the nonasthmatic children (p < 0.0001). There was no significant difference in exhaled-TGF-β1 levels after the exercise challenge in the nonasthmatics. The exhaled-TGF-β1 levels were significantly lower in those children with asthma exacerbation when compared to the stable asthmatic children (p = 0.0003). Conclusion Our results suggest that TGF-β1 may play a role in suppressing airway reactivity and its deficiency is associated with asthma exacerbation.

Differences in laryngeal movements during exercise in healthy and dyspnoeic adolescents

ObjectivesTo compare glottic and supraglottic movements in healthy adolescents and adolescents experiencing dyspnoea during strenuous exercise. MethodsUsing the continuous laryngoscopy exercise (CLE)-test laryngeal movements during exercise were analysed in healthy controls (n = 28) and compared to subjects with exercise induced bronchoconstriction (EIB) (n = 10), exercise induced laryngeal obstruction (EILO) (n = 10) and subjects experiencing exercise-induced dyspnoea without having any of these diagnoses (n = 31). Images from the video recordings were assessed regarding glottic angle, glottic area and supraglottic area using the software measuring tool EILOMEA. ResultsNo significant differences were detected between controls, the dyspnoea group without a diagnosis of EIB or EILO and the EIB group regarding glottis angle, glottis area or supraglottic area at maximum effort. All three parameters differed significantly in the EILO group compared to the other groups (p=<0.001). In the group with EILO all but one had supraglottic obstruction (corresponding to a CLE-test score ≥2). Movement of the laryngeal structures, corresponding to a CLE-test score of 1, at glottic and/or supraglottic level was seen in 26 of 35 (74%) of controls, 34 out of 41 (83%) of patients in the dyspnoea group, and in 25 of 38 (66%) of EIB-subjects. ConclusionMinor movements at both glottic and supraglottic level are equally common in healthy controls as among adolescents with exercise induced dyspnoea without EIB or EILO and adolescents with EIB. Adolescents with EILO had a statistically significant more pronounced supraglottic obstruction than the other groups.

P230 DEMOGRAPHICS, TREATMENT PATTERNS, AND MORBIDITY IN PATIENTS WITH EXERCISE-INDUCED BRONCHOCONSTRICTION: AN ADMINISTRATIVE CLAIMS DATA ANALYSIS

Exercise-induced bronchoconstriction (EIB) occurs as a distinct condition or associated with asthma. Short-acting beta2-agonist (SABA) treatment is generally recommended, but there is less consensus on anti-inflammatory therapy use. This study describes demographics, treatment patterns, and morbidity of patients with EIB vs EIB+asthma.

Classification of asthma.

Asthma is a chronic inflammatory disorder of the airways that results, physiologically, in hyperreactivity and, clinically, in recurrent episodes of wheezing, chest tightness, or coughing. Airway inflammation, smooth-muscle contraction, epithelial sloughing, mucous hypersecretion, bronchial hyperresponsiveness, and mucosal edema contribute to the underlying pathophysiology of asthma. Diagnostic tests such as methacholine or mannitol challenges or spirometry (pre- and postbronchodilator responses) help to identify such underlying pathophysiology via assessments of bronchial hyperreactivity and lung mechanics but are imperfect and, ultimately, must be viewed in the context of a patient's clinical presentation, including response to pharmacotherapy. Asthma can be classified into either intermittent or persistent, and the latter is either mild, moderate, or severe. Some patients change, in either direction, from intermittent to persistent asthma. In addition, patients with asthma may be classified as allergic (immunoglobulin E mediated), nonallergic (often triggered by viral upper respiratory tract infections or no apparent cause), occupational, aspirin-exacerbated respiratory disease, potentially fatal, exercise-induced, and cough variant asthma. In the latter, the patients have a nonproductive cough that responds to treatment for asthma but not with antibiotics, expectorants, mucolytics, antitussives, or beta₂-adrenergic agonists, and to treatment for acid reflux and rhinosinusitis. Thus, cough variant asthma is in the differential diagnosis of chronic cough.

Dehydration affects exercise-induced asthma and anaphylaxis.

Allergies are generally triggered by food, medication, physical exercise, stress, alcohol consumption, and dehydration. There are reports that indicate dehydration affects various kinds of physical allergies. However, there are few studies that have focused on the effects of dehydration on asthma and allergy anaphylaxis. Therefore, we analyzed the effects of dehydration on several kinds of allergy responses and exercise-induced asthma especially during the endurance exercise. PubMed was searched from April to July of 2019 using predefined search terms “dehydration,” “exercise,” and “allergy responses.” Based on the reference search, more than one-hundred articles were identified but eighteen papers met the inclusion criteria and were analyzed for connections among exercise and dehydration, dehydration and exercise-induced asthma, and allergy responses in the main text. Results suggest that dehydration directly impairs stroke volume, cardiac output, and skin blood flow. This results in larger increases in core temperature, heart rate, and stroke volume. Additionally, exercise-induced dehydration reduces airway surface hydration, which results in an amplified brocnchoconstriction. This response to exercise occurs in those who suffer from exercise-induced asthma. Moreover, damage to the gut and impaired gut function relates to increased intestinal permeability after endurance exercise. Endurance exercise changes the immunological profiles to activate antibody-mediated immunity. Also, numerous mast cells and eosinophils were recruited, therefore isotype switching to IgE antibodies occur, this hypersensitivity activates mast cell degranulation. After degranulation, proteases, leukotrienes, prostaglandins, and histamine lead to many kinds of allergy symptoms.

Does exercise-induced bronchoconstriction affect physical activity patterns in asthmatic children?

Exercise-induced bronchoconstriction (EIB) is a sign of uncontrolled childhood asthma and classically occurs after exercise. Recent research shows that EIB frequently starts during exercise, called breakthrough-EIB (BT-EIB). It is unknown whether this more severe type of EIB forces children to adapt their physical activity (PA) pattern in daily life. Therefore, this pilot study aims to investigate daily life PA (amount, intensity, duration, and distribution) in children with BT-EIB, 'classic' EIB, and without EIB. A Fitbit Zip activity tracker was used for one week to objectively measure daily life PA at one-minute intervals. Thirty asthmatic children participated. Children with BT-EIB were less physically active compared to children without EIB (respectively 7994 and 11,444 steps/day, p = .02). Children with BT-EIB showed less moderate-to-vigorous PA compared to the children without (respectively 117 and 170 minutes/day, p = .02). Children with EIB (both BT and classic) had significant shorter bouts of activity and a less stretched distribution of bout lengths compared to the non-EIB group (all p < .05). These results emphasize a marked association between EIB severity and PA patterns in daily life, stressing the need for a thorough clinical evaluation of exercise-induced symptoms in childhood asthma.

Broncholithiasis Masquerading as Asthma

Broncholithiasis is the presence of osteoid material molded in the bronchial lumen.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar It produces chronic inflammation leading to airway obstruction mimicking asthma. A 52-year-old lifelong nonsmoker woman complained of constant, progressive, dry cough for 3 months. The patient denied precipitating factors, previous events, and aggravating or alleviating factors. Her cough was associated with halitosis, subjective weight loss, chest tightness, wheezing, urinary stress incontinence, and dyspnea. Past medical history was significant for exercise-induced bronchospasm, she denied the use of prescribed or over-the-counter medication, and the physical examination revealed expiratory wheezing. On the basis of findings, we diagnosed asthma. The result of the methacholine challenge was positive; nonetheless, the patient did not improve after a trial of 2 dry-powder inhalers with high-dose inhaled corticosteroids/long-acting beta-agonist (fluticasone propionate/salmeterol and fluticasone furoate/vilanterol), and systemic steroids. Two episodes of pneumonia complicated her course, and a chest computed tomography performed after the second episode revealed a broncholith in the right bronchus (Figure 1). Finally, the foreign material was extracted with a bronchoscope (Figure 2), leading to complete symptomatic relief.Figure 2Broncholith material after bronchoscopic removal.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Most cases of broncholithiasis are secondary to chronic lymphadenitis caused by histoplasmosis, foreign body aspiration, ossified bronchial cartilage, and osteoid material migration from other parts of the body.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar Patients often present with chronic cough, dysphagia, lithoptysis, hemoptysis, and recurrent pneumonias.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar Often, findings in x-rays are nonspecific (hilar calcification or parenchymal infiltrates, depending on the etiology), so a computed tomography is required to diagnose, localize, and detect the degree of airway obstruction.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar Clinical management is preferred over surgery because of the risk of bleeding; however, severe cases require bronchoscopic or surgical extraction.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar In conclusion, broncholithiasis can produce airway obstruction and chronic inflammation resembling asthma.1Krishnan S. Kniese C.M. Mankins M. Heitkamp D.E. Sheski F.D. Kesler K.A. Management of broncholithiasis.J Thorac Dis. 2018; 10: S3419-S3427Crossref Scopus (10) Google Scholar Physicians must consider alternative diagnoses in patients with atypical asthma, unresponsive to medical treatment in spite of a positive methacholine challenge test result.2Coates A.L. Wanger J. Cockcroft D.W. Culver B.H. Carlsen K. Diamant Z. et al.ERS technical standard on bronchial challenge testing: general considerations and performance of methacholine challenge tests.Eur Respir J. 2017; 49: 1601526Crossref PubMed Scopus (176) Google Scholar

EXERCISE INDUCED BRONCHOCONSTRICTION IN MEDICAL STUDENTS

INTRODUCTION: Exercise induced bronchoconstriction (EIB) is transient narrowing of lower respiratory tract airways after exercise. It affects about 5 to 20 % of healthy individuals and 80% of Asthmatics. Obesity has been considered as one of the risk factor to the development of EIB. Symptoms of EIB are nonspecific and can be seen in a variety of disorders and studies have shown a lack of diagnosis specificity and sensitivity based on symptoms. AIM: The aim of this study was to evaluate frequency of EIB in Medical students of Govt. Medical College Miraj. We also tried to find out association of body mass index (BMI) with EIB. We also tried to find out correlation of subjective feeling of breathlessness (symptom of EIB) with actual findings of spirometry tests used to asses EIB. METHOD: This cross-sectional observational study was conducted on 80 male medical students. Exercise challenge test was conducted for participants. Pre and post-test values of Forced expiratory volume in one second (FEV1) and Peak expiratory flow rate (PEFR) were compared and students with ≥ 10% decrease in post-test FEV1 &amp; PEFR were considered positive cases of exercise induced bronchoconstriction. Statistical analysis was done by using software, IBM-SPSS VER 20. RESULT:In our study frequency of EIB in medical students was 6.4%. Decrease in post-test FEV1 and PEFR values were statistically significant with Pvalue &lt; 0.001. Our findings show that there was no association between BMI and EIB. Our study results also reveal strong correlation between subjective feeling of breathlessness measured in terms of visual analogue scale (VAS) and objective spirometry tests used to assess EIB. CONCLUSION: EIB is one of the major problems to be addressed as increasing frequency of EIB in healthy population could pose a threat when people attempt exercise training for their health benefits. Proper care with physician's consultation can minimize undue risks associated with EIB in healthy people.