Effects of single-dose fluticasone on exercise-induced asthma in asthmatic children: a pilot study. Inhibition of exercise-induced-asthma (EIA) by nedocromil sodium and sodium cromoglycate in children. Exercise-induced bronchoconstriction as an expression of bronchial hyperreactivity: a study of its mechanisms in children. Dose-responses over time to inhaled fluticasone propionate treatment of exercise- and methacholine-induced bronchoconstriction in children with asthma. Reduced protection against exercise induced bronchoconstriction after chronic dosing with salmeterol. Inhaled beta-agonists improve lung function but not maximal exercise capacity in cystic fibrosis. Low-dose budesonide improves exercise-induced bronchospasm in schoolchildren. Exercise training improves recovery in patients with COPD after an acute exacerbation.
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 (FEV(1)) was assessed for 4 hr before exercise. Then an exercise challenge was performed on a treadmill to assess EIB (% fall FEV(1)). A significant increase in FEV(1) was observed 1 hr after inhalation of FP compared to placebo. Response to exercise was expressed as maximal % fall in FEV(1) from baseline (% fall) and as area under the curve (AUC) of the 30-min time/response curve. The % fall FEV(1) 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.
                Copyright 2001 Wiley-Liss, Inc. Nedocromil sodium (Ned) 4 mg, sodium cromoglycate (SCG) 10 mg, and placebo were compared for their efficacy in preventing exercise-induced asthma. Nineteen asthmatic children aged six to 15 years performed a treadmill exercise test before and 20' after a single dose of drug in a double-blind trial. Both active drugs performed significantly better than placebo; in fact the exercise challenge resulted in a mean maximum fall in FEV1 of 26.1 +/- 14.9% after placebo, but only of 14.6 +/- 11.5% after SCG (P < 0.05), and 11.0 +/- 12.4% after Ned (p < 0.01). Measurements of PEFR gave similar results, while the effect of treatment on FEF 25-75 was significant for Ned alone (p < 0.05). Direct comparison between Ned and SCG at different time points demonstrated significant differences in FEV1 at 1 min (p < 0.05) with a better overall performance of Ned. In individual patients, complete protection was provided in 9 patients with SCG, in 14 patients with Ned and in 2 with placebo. No side effects were observed. This study suggests that at the dosages used there are only slight differences between SCG and Ned activity in the prevention of exercise-induced asthma. The mechanism of exercise-induced bronchoconstriction (EIB) was studied by observing the protective effects of several aerosol agents in a double-blind, randomised trial. Exercise-induced bronchoconstriction was not affected by placebo, but was reduced by each agent used (p less than 0.001). Blocking the parasympathetic system had the weakest effect, while beta 2 adrenergic stimulation produced the strongest effect which was significantly different from the parasympatholytic (p less than 0.02). The effect of the mast cell stabilizer, sodium cromoglycate (SCG) was found to be intermediate. However in some patients SCG had a stronger effect than the beta 2 adrenergic agonist. A relationship was found between EIB and bronchial hyperreactivity induced by histamine (p less than 0.05). When treating bronchial hyperresponsiveness to so-called direct and indirect stimuli, distinct pathophysiological mechanisms might require differences in dose and duration of inhaled corticosteroid therapy. To test this hypothesis in children with asthma, we investigated the time- and dose-dependent effects of 2 doses of fluticasone propionate (FP, 100 or 250 microg bid.) in improving exercise- (EIB) and methacholine-induced bronchoconstriction during 6 months of treatment, using a placebo-controlled parallel group study design. Thirty-seven children with asthma (aged 6 to 14 years; forced expired volume in 1 sec (FEV(1)) >/=70% predicted; EIB >/=20% fall in FEV(1) from baseline; no inhaled steroids during the past 4 months) participated in a double-blind, placebo-controlled, 3-arm parallel study. Children receiving placebo were re-randomized to active treatment after 6 weeks. Standardized dry air treadmill exercise testing (EIB expressed as %fall in FEV(1) from baseline) and methacholine challenge using a dosimetric technique (expressed as PD(20)) were performed repeatedly during the study. During FP-treatment, the severity of EIB decreased significantly as compared to placebo within 3 weeks, the geometric mean % fall in FEV(1) being reduced from 34.1% to 9.9% for 100 microg FP bid, and from 35.9% to 7.6% for 250 microg FP bid (P < 0.05). These reductions in EIB did not differ between the 2 doses and were sustained throughout the treatment period. PD(20) methacholine improved significantly during the first 6 weeks as compared to placebo (P < 0.04) and steadily increased with time in both treatment limbs (P = 0.04), the difference in improvement between doses (100 microg FP bid, 1.6 dose steps; 250 microg FP bid, 3.3 dose steps) approaching significance after 24 weeks (P = 0.06). We conclude that in childhood asthma, the protection afforded by inhaled fluticasone propionate against methacholine-induced bronchoconstriction is time- and dose-dependent, whereas protection against EIB is not. This suggests different modes of action of inhaled steroids in protecting against these pharmacological and physiological stimuli. This has to be taken into account when monitoring asthma treatment.
                Copyright 2000 Wiley-Liss, Inc. The purpose of the present study was to assess the degree of protection of inhaled salmeterol against exercise-induced bronchoconstriction (EIB) after chronic compared with single dosing in patients with asthma. Twelve patients with exercise-induced asthma took part in a randomized double-blind crossover study to compare the duration of action of inhaled salmeterol 50 micrograms twice daily for 4 weeks with that of placebo. A standardized exercise test was performed at 6 h and 12 h after dosing on the first and last day of each treatment period. Salmeterol produced significant protection against EIB at 6 and 12 h after the first dose in comparison with placebo, whereas there was no significant attenuation of EIB after 4 weeks of chronic treatment with salmeterol. The percentage fall in FEV1 after exercise challenge at 6 h was (first dose): placebo 34.8 +/- 4.9% vs. salmeterol 11.9 +/- 2.8% (P < 0.05); (4 weeks): placebo 32.9 +/- 5.3% vs. salmeterol 24.0 +/- 4.4% (NS). These results suggest that tachyphylaxis may develop to the functional antagonism of salmeterol against EIB. To investigate the effects of inhaled beta-agonists on sub-maximal and maximal exercise capacity, breathing pattern, dyspnoea, leg-discomfort and spirometry in patients with cystic fibrosis (CF).
                Eight patients performed two maximal incremental cycle-ergometry tests on separate days with inhaled placebo or salbutamol (600 microg) administered before each test in a randomized, double-blind, placebo-controlled crossover trial. Primary outcomes were exercise duration (Exdur) in seconds (s) and maximal oxygen uptake (VO2max) in litres/minute (L/min). Forced expiratory volume in 1 s (FEV1) was measured immediately pre-inhaler, post-inhaler and post-exercise. Dyspnoea and leg-discomfort were assessed post-exercise.
                Within-day FEV1 comparisons demonstrated that the placebo test day FEV1 improved significantly post-exercise (0.11 L, p<0.05) and the salbutamol test day FEV1 improved significantly post-inhaler (0.22 L, p<0.001) and post-exercise (0.07 L, p<0.01). Between-day FEV1 comparisons demonstrated significant improvements in post-inhaler (0.17 L, p<0.05) and post-exercise (0.13 L, p<0.05) FEV1 following salbutamol. Sub-maximal and maximal exercise showed no significant difference as shown by Exdur (547+/-154 s vs. 529+/-127 s) and VO2max (1.9+/-0.5 L/min vs. 1.9+/-0.6 L/min). No significant change in breathing pattern, dyspnoea or leg-discomfort was detected. The study had a power of 92% to detect a 10% improvement in Exdur.
                In adults with CF, salbutamol improves post-exercise FEV1 and is safe when administered immediately before exercise but does not improve exercise capacity, exercise-induced dyspnoea or leg-discomfort. The aim of this study was to compare the clinical efficacy of low-dose inhaled budesonide (once or twice daily) and placebo, administered via Turbuhaler, on exercise-induced bronchoconstriction (EIB) in children with mild asthma. Fifty-seven steroid-naive children (7-16 years old; 41 boys, 16 girls) with EIB participated in this sub-population study according to the following inclusion criterion: a maximum fall in forced expiratory volume in 1 s (FEV1) > or = 10% after a standardized treadmill test. Mean baseline FEV1 was 100.3% of predicted, and mean maximum fall in FEV1 after the standardized exercise test was 22%. The study was a double-blind, randomized, parallel-group design. After 2 weeks of run-in, the children received inhaled budesonide 100 microg or 200 microg once daily in the morning, 100 microg twice daily, or placebo, for 12 weeks. After 12 weeks of treatment, the fall in FEV1 after the exercise test was significantly less in all three budesonide groups (7.2-7.8%) vs. placebo (16.7%). Daytime symptom scores were significantly lower in all three budesonide groups compared with placebo (p <0.02). The three budesonide groups did not differ significantly, and no significant change in lung function was found in any group. Therefore children with mild asthma, but with significant EIB, improved their exercise tolerance and symptom control after 3 months of treatment with a low dose of inhaled budesonide given once or twice daily. Clinical experience suggests that exercise is beneficial for recovery after an acute exacerbation in patients with severe chronic obstructive pulmonary disease (COPD). The aim of this study was to quantify the clinical benefit of exercise in these patients. Twenty-nine inpatients were randomly assigned to a training group (n = 15, FEV1 34% pred) or a control group (n = 14, FEV1 38% pred). On ten consecutive days, patients in the training group performed a 6-min treadmill walking test and, in addition, five walking sessions per day at > or = 75% of the respective treadmill walking distance. Patients in the control group performed only treadmill walking tests on days 1, 5, and 10. To directly compare the possible benefit of exercise training all patients had an exercise test on day 11 at the same work load as on day 1. In the training group, 6-min walking distance increased from 237 to 420 m, in the control group from 230 to 255 m over the 10 day period which was significantly different (P < 0.0001). Minute ventilation and oxygen uptake increased significantly (P < 0.05) in the training but not in the control group. When comparing exercise tests on days 1 and 11, minute ventilation, oxygen uptake, PaCO2, lactic acid concentration, and Borg scale were significantly reduced to achieve the same work load (P < 0.01) only in the training group. Intrathoracic gas volume and residual volume decreased, and FEV1 and vital capacity increased in the training (P < 0.05) but not in the control group. Our data demonstrate that exercise training significantly improves the exercise capacity in patients with severe COPD after an acute exacerbation of their disease.
No significant differences were evident between the effect of NCS and SCG during the immediate post-exercise period in adults and children with EIB with regards to pulmonary function - specifically maximum percent decrease in FEV1, complete protection, clinical protection, or side effects.