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Exercise Challenge (exercise + challenge)
Selected AbstractsPredictive value of allergy and pulmonary function tests for the diagnosis of asthma in elite athletesALLERGY, Issue 10 2007M. Bonini Background:, Asthma is frequently found in athletes, often associated with rhinitis and allergy. Aim:, To study the predictive value of allergy and pulmonary function tests for the diagnosis of asthma in athletes. Subjects and methods:, Ninety-eight national preOlympic athletes underwent an accurate medical examination including a validated questionnaire for asthma and rhinitis, spirometric recordings and skin prick testing with a panel of the most frequent inhalant allergens. Bronchodilator and/or exercise challenge were also performed in asthmatic subjects. Results:, Clinical asthma was present in 20.4% of athletes, rhinitis in 35.3% (in 21.4% of cases alone and in 13.9% associated with asthma). Positive prick tests were recorded in 44.4% of athletes (in 60.5% of asthmatics, in 95.2% of rhinitics and in 21.0% of nonasthmatic , nonrhinitic subjects). Mean spirometric values and distribution of abnormal values were not different among asthmatics, rhinitics and nonasthmatics , nonrhinitic patients. Skin-tests positivity was not related to the abnormal spirometric data found in individual cases. Provocation tests with bronchodilators or exercise did not appear sensitive enough to diagnose mild forms of asthma in subjects with normal basal spirometric values. Conclusions:, Allergy testing and spirometry should be performed routinely in athletes because of the high prevalence of allergy, rhinitis and asthma in this population. However, the predictive value of these tests and of the bronchial provocation tests performed in this study seems too low to document mild or subclinical asthma in athletes. [source] Seasonal variability in exercise test responses in GhanaPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4 2002Emmanuel O. D. Addo-Yobo Exercise-induced bronchospasm (EIB) is widely used in epidemiological studies to investigate the prevalence of asthma. We aimed to determine seasonal variations in the prevalence of EIB in Ghanaian school children from urban-rich (UR), urban-poor (UP), and rural (R) schools. We have previously reported the prevalence of EIB in 9,16-year-old children to be 3.1% in the dry season, with UR children having a significantly higher prevalence of both EIB and atopy compared to UP or R children. In the current study, the prevalence of EIB was assessed in the same 1,095 children in the wet season (5 months following the initial study) using the same methodology. Exercise provocation consisted of free running outdoors for 6 min. In the wet season, 17/1,095 children [mean 1.55%, 95% confidence interval (CI): 0.91,2.47] had a positive response to exercise, compared to our previous report of 34 children (mean 3.1%, 95% CI: 2.15,4.32) with EIB in the dry season (dry vs. wet season, difference 1.55, 95% CI: 0.41,2.69). The proportion of children with a positive response to exercise in the UR school fell from 4.2% (25/599) to 1.3% (8/599) (difference 2.9, 95% CI: 1.2,4.5). In the wet season, there was no difference in the prevalence of EIB among the UR, UP, and R children. Only five of 1,095 subjects (mean 0.5%, 95% CI: 0.15,1.07) demonstrated EIB in both seasons. In conclusion, although exercise challenge remains a useful tool for determining asthma prevalence in epidemiological studies, seasonal variations in the pattern of responses may occur and the results should be interpreted with caution. [source] Pilot study: The effect of reducing treatment on exercise induced bronchoconstriction,PEDIATRIC PULMONOLOGY, Issue 9 2010E.T.G. Kersten MD Abstract Rationale Asthma therapy should be stepped up or stepped down in response to changes in asthma control. However, there is little evidence available on the optimal timing, sequence, and degree of medication reductions. In this study we analyzed clinically stable asthmatic children who underwent a medication reduction from a combination preparation consisting of an inhaled corticosteroid (ICS) and long acting beta2-agonist (LABA) to monotherapy with the same dose of the ICS. We hypothesized that the extent of exercise-induced bronchoconstriction (EIB) would not increase after the cessation of the LABA. Methods Nineteen children, aged 8,16 years, with clinically stable asthma, receiving LABA/ICS combination therapy, were analyzed in this open-label pilot study. Children performed an exercise challenge at baseline and 3 weeks after the medication reduction. Best values of spirometric measurements of the forced expiratory volume in 1,sec (FEV1) were used for statistical calculations. Results Maximum percent fall in FEV1 was significantly lower after 3 weeks of ICS monotherapy (P,=,0.03). Eight of 19 children had a ,15% fall in FEV1 after exercise at the initial exercise challenge. In this subgroup, maximum percent fall in FEV1 after the medication reduction was significantly lower (P,<,0.01), and in six children it decreased to <15%, indicating they no longer had EIB. Conclusion In clinically stable asthmatic children on LABA/ICS combination therapy, the cessation of the LABA can reduce and in most cases abolish EIB. Pediatr. Pulmonol. 2010; 45:927,933. © 2010 Wiley-Liss, Inc. [source] Airway hyperresponsiveness and acute chest syndrome in children with sickle cell anemiaPEDIATRIC PULMONOLOGY, Issue 3 2007Karl P. Sylvester PhD Abstract To determine the occurrence and magnitude of airway hyperresponsiveness (AHR) in children with sickle cell anemia (SCA) who had or had not had acute chest syndrome (ACS) episodes. A subsidiary aim was to determine whether cold air and exercise challenge testing gave similar results in children with SCA. AHR would be greater in SCA children who had had an ACS episode compared to those who had not. Prospective observational study. Forty-two SCA children (median age of 11.5 [range 6.1,16.8] years); 12 children had been previously hospitalized for an ACS episode. AHR was assessed by the change in forced expiratory volume in 1 sec (FEV1) to a cold air challenge and in a subset of the children to an exercise challenge. A positive result to either challenge was deemed to have occurred if the FEV1 fell by at least 10% from the pre-challenge baseline. The magnitude of change in FEV1 following the cold air challenge was similar in children who had or had not had an ACS episode. Six children had a positive response to the cold air challenge (AHR); none had had an ACS hospitalization. Similar proportions of children responded to the cold air and exercise challenge and the magnitude of response to the two tests was similar. Some children, however, responded only to a cold air challenge and others only to an exercise challenge. SCA children who had had an ACS hospitalization episode compared to those who had not were not more likely to respond to a cold air challenge. Importantly, if AHR is to be correctly diagnosed, some SCA children will require to undergo both cold air and exercise challenge testing. Pediatr Pulmonol. 2007; 42:272,276. © 2007 Wiley-Liss, Inc. [source] Effects of single-dose fluticasone on exercise-induced asthma in asthmatic children: A pilot study,PEDIATRIC PULMONOLOGY, Issue 2 2001B.J. Thio MD Abstract A single high dose of inhaled corticosteroid (ICS) can increase airway caliber in children with asthma attacks and laryngitis subglottica. Presumably the effect is due to the vasoconstrictive and antiedematous properties of topical steroids. Enlarged vessels have been suggested to play a role in the pathophysiology of exercise-induced bronchial obstruction (EIB). To investigate this, we evaluated the effect of a single high dose of fluticasone propionate (FP) on EIB in asthmatic children. Nine children aged 8,16 years with mild to moderate asthma were included. All children had a history of EIB, which was confirmed by an exercise test. None was taking ICS maintenance therapy. The children inhaled either a single dose of 1 mg FP or placebo on 2 separate days within 7,14 days. After inhalation, airway caliber (FEV1) was assessed for 4 hr before exercise. Then an exercise challenge was performed on a treadmill to assess EIB (% fall FEV1). A significant increase in FEV1 was observed 1 hr after inhalation of FP compared to placebo. Response to exercise was expressed as maximal % fall in FEV1 from baseline (% fall) and as area under the curve (AUC) of the 30-min time/response curve. The % fall FEV1 after exercise and the AUC were significantly reduced when FP was inhaled compared to placebo inhalation (% fall 9.7% vs. 19.2%, respectively, P,=,0.038 and AUC 92.0%,min vs. 205.7%,min, respectively, P,=,0.03). There was considerable individual variability in reduction of EIB, with 5 out of 9 children having a clinically significant response. We conclude that a single high dose of inhaled FP has an acute protective effect on the bronchial response to exercise in a substantial proportion of asthmatic children. Pediatr Pulmonol. 2001; 32:115,121. © 2001 Wiley-Liss, Inc. [source] Disconnect between standardized field-based testing and mannitol challenge in Scottish elite swimmersCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2010K. L. Clearie Summary Background Elite swimmers have high rates of rhinoconjunctivitis and exercise-induced bronchoconstriction. Moreover, exposure to chlorine and chlorine metabolites is known to induce bronchial hyper-reactivity. Objective To assess the early and late effects of chlorine and exercise on the unified airway of elite swimmers, and to compare the response to mannitol and field-based exercise challenge. Methods The Scottish national squad underwent exhaled tidal (FENO) and nasal (NNO) nitric oxide measurement, peak nasal inspiratory flow (PNIF), and forced expiratory volume in 1 s before, immediately after, and 4,6 h post-swimming. A sport-specific exercise test was carried out during an intensive lactate set (8 min at 80% maximum hear rate). All swimmers underwent mannitol challenge, and completed a health questionnaire. Results N=61 swimmers were assessed: 8/59 (14%) of swimmers had a positive mannitol challenge. Nine out of 57 (16%) of swimmers had a positive exercise test. Only one swimmer was positive to both. Swimmers with a positive mannitol had a significantly higher baseline FENO (37.3 vs. 18.0 p.p.b., P=0.03) than those with a positive exercise challenge. A significant decrease in FENO was observed pre vs. immediate and delayed post-chlorine exposure: mean (95% CI) 18.7 (15.9,22.0) p.p.b. vs. 15.9 (13.3,19.1) p.p.b. (P<0.01), and 13.9 (11.5,16.7) p.p.b. (P<0.01), respectively. There were no significant differences in NNO. Mean PNIF increased from 142.4 L/min (5.8) at baseline to 162.6 L/min (6.3) immediately post-exposure (P<0.01). Delayed post-exposure PNIF was not significantly different from pre-exposure. Conclusions No association was found between mannitol and standardized field-based testing in elite swimmers. Mannitol was associated with a high baseline FENO; however, exercise/chlorine challenge was not. Thus, mannitol may identify swimmers with a ,traditional' inflammatory asthmatic phenotype, while field-based exercise/chorine challenge may identify a swimmer-specific bronchoconstrictor response. A sustained fall in FENO following chlorine exposure suggests that a non-cellular, perhaps neurogenic, response may be involved in this group of athletes. Cite this as: K. L. Clearie, P. A. Williamson, S. Vaidyanathan, P. Short, A. Goudie, P. Burns, P. Hopkinson, K. Meldrum, L. Howaniec and B. J. Lipworth, Clinical & Experimental Allergy, 2010 (40) 731,737. [source] MRP1/GS-X pump ATPase expression: is this the explanation for the cytoprotection of the heart against oxidative stress-induced redox imbalance in comparison to skeletal muscle cells?CELL BIOCHEMISTRY AND FUNCTION, Issue 1 2007Maurício S. Krause Abstract Striated muscle activity is always accompanied by oxidative stress (OxStress): the more intense muscle work and/or its duration, the more a redox imbalance may be attained. In spite of cardiac muscle functioning continuously, it is well known that the heart does not suffer from OxStress-induced damage over a broad physiological range. Although the expression of antioxidant enzymes may be of importance in defending heart muscle against OxStress, a series of combined antioxidant therapeutic approaches have proved to be mostly ineffective in avoiding cellular injury. Hence, additional mechanisms may be involved in heart cytoprotection other than antioxidant enzyme activities. The strong cardiotoxic effect of doxorubicin-induced cancer chemotherapy shed light on the possible role for multidrug resistance-associated proteins (MRP) in this context. Muscle activity-induced ,physiological' OxStress enhances the production of glutathione disulfide (GSSG) thus increasing the ratio of GSSG to glutathione (GSH) content inside the cells, which, in turn, leads to redox imbalance. Since MRP1 gene product (a GS-X pump ATPase) is a physiological GSSG transporter, adult Wistar rats were tested for MRP1 expression and activity in the heart and skeletal muscle (gastrocnemius), in as much as the latter is known to be extremely sensitive to muscle activity-induced OxS. MRP1 expression was completely absent in skeletal muscle. In contrast, the heart showed an exercise training-dependent induction of MRP1 protein expression which was further augmented (2.4-fold) as trained rats were challenged with a session of acute exercise. On the other hand, inducible expression of the 70-kDa heat shock protein (HSP70), a universal marker of cellular stress, was completely absent in the heart of sedentary and acutely exercised rats, whereas skeletal muscle showed a conspicuous exercise-dependent HSP70 expression, which decreased by 45% with exercise training. This effect was paralleled by a 58% decrease in GSH content in skeletal muscle which was even higher (an 80%-fall) after training thus leading to a marked redox imbalance ([GSSG]/[GSH] raised up to 38-fold). In the heart, GSH contents and [GSSG]/[GSH] ratio remained virtually unchanged even after exercise challenges, while GS-X pump activity was found to be 20% higher in the heart related to skeletal muscle. These findings suggest that an intrinsic higher capacity to express the MRP1/GS-X pump may dictate the redox status in the heart muscle thus protecting myocardium by preventing GSSG accumulation in cardiomyocytes as compared to skeletal muscle fibres. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||