A placebo-controlled, double-blind trial of the long-term effects of albuterol administration in patients with cystic fibrosis. Bronchodilatory effects of salbutamol, ipratropium bromide, and their combination: double-blind, placebo-controlled crossover study in cystic fibrosis. Acute bronchodilator response to a combination of beta-adrenergic and anticholinergic agents in patients with cystic fibrosis. Effectiveness and tolerability of high-dose salmeterol in cystic fibrosis. Inhaled beta-agonists improve lung function but not maximal exercise capacity in cystic fibrosis. [The effect of ipratropium bromide on lung function in patients with cystic fibrosis]. Effects of standard and high doses of salmeterol on lung function of hospitalized patients with cystic fibrosis. A controlled trial of long-term bronchodilator therapy in cystic fibrosis. The effects of albuterol on the lung function of hospitalized patients with cystic fibrosis. Effects of salmeterol on arterial oxyhemoglobin saturations in patients with cystic fibrosis. Effect of albuterol on maximal exercise capacity in cystic fibrosis. Efficacy of salbutamol and ipratropium bromide in decreasing bronchial hyperreactivity in children with cystic fibrosis. The effect of high doses of inhaled salbutamol and ipratropium bromide in patients with stable cystic fibrosis.
This placebo-controlled study was designed to confirm a previously performed open label study that showed significant improvement in spirometry on maintenance therapy with albuterol for 1 year. In a double-blind, cross-over trial, albuterol (by metered dose inhaler) 180 microg b.i.d. or placebo were given for 6 months each. Spirometry was monitored at the start, and 3 and 6 months following initiation of each arm of the study. Peak expiratory flow rate (PEFR) was measured twice daily at home before and after study drug administration. Only patients with clinically detectable lung disease were enrolled. Twenty-one patients finished the study. All spirometric tests showed a significant improvement from start to end of the 6 month treatment with albuterol; there was no significant change on placebo. Forced vital capacity improved by 8.2% and forced expiratory volume in 1 s by 12.1% on albuterol therapy. Nevertheless, there was no significant difference between change on albuterol and change on placebo. Home measurements of PEFR showed a significant improvement of 4.7% on albuterol and a non-significant change of 2.0% on placebo from the first to the last week of treatment. None of the long-term improvements (spirometry or home PEFR) correlated with mean daily bronchodilation. For albuterol, the number of days of hospitalization was less than half that for patients on placebo (1.0/patient on albuterol versus 2.6 on placebo), but this did not reach statistical significance. These results suggest a beneficial effect from maintenance therapy with albuterol. Bronchodilation alone probably cannot explain the long-term benefits of albuterol, and other mechanisms may play a role. The lack of significant difference between change on albuterol and change on placebo is probably due to too small a number of patients in this study and lack of statistical power. The efficacy of inhaled sympathomimetic and anticholinergic agents on airway obstruction in cystic fibrosis (CF) has been proven in several studies. However, studies comparing combined therapy with monotherapy led to divergent results, probably due to different study designs, different dosages, and the small numbers of patients investigated. Therefore, we wanted to answer the question which inhalation has the best short term effect: a sympathomimetic or an anticholinergic agent, or the combination of both. We investigated 17 patients with CF on 4 successive days in the morning, using pulmonary function testing before and 30 min after inhalation. Each patient received aerosolized salbutamol (SB, maximum dose (max.) 2.5 mg), ipratropium bromide (IB, max. 0.5 mg), the combination of both, or placebo (normal saline) in a randomized, double-blind crossover design. The mean forced expiratory volume in the first second improved significantly (adjusted P-value < 0.017) after each treatment compared to placebo. Analysis of variance showed that SB and combination therapy with SB and IB were superior to IB alone, without significant difference between SB and combination therapy. Response of a patient to combined therapy was usually associated with response to SB. Long-term efficacy and side effects of treatment with bronchodilators still remain to be investigated after this short term study. We conclude that in CF patients bronchodilator therapy with sympathomimetic agents is usually sufficient. Only in cases with proven additional benefit from inhalation by anticholinergics should combination therapy be recommended. Patients with cystic fibrosis had a better acute bronchodilator response to albuterol and ipratropium bromide than to either drug alone. Further studies of long-term efficacy and safety seem justified. The efficacy and tolerability of high-dose salmeterol (100 mcg, BID) and albuterol (2.5 mg, BID) were compared with those of albuterol (2.5 mg, BID) in outpatients with cystic fibrosis in a randomized, double-blind, double-dummy, placebo-controlled, crossover study with both short- (4 weeks of each) and long-term (24 weeks of each) treatment periods. The primary outcome measure was the difference in mean change in forced expired volume in 1 sec (FEV(1)) from baseline to the end of each treatment, and secondary measures included changes in forced vital capacity (FVC), forced expiratory flow between 25-75% of FVC (FEF(25-75)), patient-rated weekly symptom scores, number of extra (rescue) albuterol treatments, and number of antibiotic treatments. Tolerability was evaluated by changes in vital signs and adverse events.Thirty-six out of 44 patients enrolled finished the short-term treatment period, and 19 out of 23 who continued the study also finished the long-term treatment period. There was no significant difference in the mean % change in FEV(1) from baseline to completion of 4 weeks with each drug in the short-term treatment period (0.1% vs. 0.06%, albuterol vs. salmeterol; respectively). In the long-term treatment period, there was a significant decrease from baseline in FEV(1) with albuterol vs. salmeterol, as measured after both 12 and 24 weeks of each treatment (-6.2% vs. 1.8%, P = 0.013 after 12 weeks, and -6.5% vs. 1.7%, P = 0.002, after 24 weeks, respectively). In both treatment periods, salmeterol was well-tolerated. While there were more rescue treatments per patient per week with albuterol than with salmeterol treatment in both the short- and long-term periods (0.67 vs. 0.40 and 1.76 vs. 0.74, respectively), rescue treatments were needed significantly more often for only the long-term period with albuterol compared to salmeterol (P = 0.022). Also, there were more antibiotic interventions with albuterol than with salmeterol treatment in both the short- and long-term periods (25 vs. 10 and 56 vs. 42, respectively); however, antibiotics were needed significantly more often for only the short-term period (P = 0.011). In addition, there was a significantly higher symptom score with albuterol vs. salmeterol treatment during the second half of the long-term period (1.24 vs. 0.89, P = 0.001).In conclusion, long-term high-dose salmeterol was equally safe and was associated with better pulmonary function, fewer interventions, and fewer respiratory symptoms compared to standard therapy with albuterol in a population of outpatients with mild to moderate CF.
                Copyright 2002 Wiley-Liss, Inc. 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 main manifestation of cystic fibrosis (CF) of the lungs is an obstructive ventilation disturbance. The fact that the administration of atropine improves pulmonary function in patients with CF suggests a vagal mechanism for the development of bronchal obstruction. In a single-blind, placebo-controlled study, we investigated the effect of 250 micrograms of an inhalation solution of the anticholinergic substance ipatropium bromide (IB) on the pulmonary function of 11 patients with CF (age range: 8 to 29 years). The mean figures for the changes in FEV1.0, FEF25-75%, RV and TLC after inhalation of IB and placebo did not differ significantly. However, FEV1.0 and FEF25-75% after administration of IB increased in 4 out of 11 patients, and decreased in one. The lung volumes changed significantly in only a single case. This variable effect of inhaled IB in CF patients is in agreement with findings that have been observed for other substances with a "bronchodilatory" effect in patients with CF. In a recent investigation we found that hospitalized patients with cystic fibrosis who received 0.5 cc of 0.5% albuterol nebulizer solution TID significantly increased their pulmonary function across the day, but fell back to baseline overnight. To determine whether this fall could be prevented by the long-acting beta-2 agonist salmeterol at both standard (2 puffs: 42 mcg BID) and high (4 puffs, 84 mcg BID) doses, we evaluated the effects of salmeterol vs. albuterol (2 puffs, 180 mcg QID, and 4 puffs, 360 mcg BID) in a placebo-controlled three-way random crossover, double-blind trial. Eighteen patients in the low-dose group and 10 of the same 18 patients in the high-dose group completed the 3 consecutive days of testing and received either salmeterol, albuterol, or placebo with each of four chest physiotherapy sessions given at 7 AM, 11 AM, 3 PM, and 7 PM. At standard doses (2 puffs), the mean percent changes in FEV1 pre- to post-7 AM therapy for salmeterol (5.5%) and albuterol (9.9%) were significantly greater than with placebo (-1.2%) (P < 0.05 and 0.01, respectively). The mean percent changes in FEV1 from morning baseline with salmeterol were also significantly greater than placebo before 3 PM (12.1% vs. 5.4%, P < 0.01), and neither albuterol nor salmeterol were significantly greater than placebo after 3 PM. At standard doses there was a significant carryover effect with salmeterol to the next morning for the FEV1 (7.3%) when compared to placebo (1.5%) and albuterol (-0.7%) (P < 0.05 and 0.05, respectively). At high doses (4 puffs), the mean percent change in FEV1 with pre- to post-7 AM therapy increased to 22.7% and remained significantly greater than with placebo until pretherapy at 7 PM. The carryover effect the next morning was 14.7%. Salmeterol at 4 puffs compared favorably to albuterol nebulizer therapy given TID in both the incidence of responders for the FEV1 (70% vs. 71%) and the mean changes after therapy at 7 AM (22.7% vs. 14.9%), and provided greater carryover effects to the next morning (14.7% vs. -0.7%), thus preventing the fall in pulmonary function back to baseline overnight. We recommend the use of high-dose salmeterol in hospitalized patients with FVC values of 40% of predicted or greater, starting with 2 and increasing to 4 puffs BID as tolerated. To evaluate the effect of long-term bronchodilator therapy in CF patients with demonstrated bronchial hyperresponsiveness, we first performed methacholine challenges to determine responsiveness, then entered 27 patients (16 methacholine responders and 11 nonresponders) into a two-month double-blind crossover trial of albuterol, 90 micrograms by inhalation four times a day vs placebo. Among the responders, daily PEFR measures improved significantly more during treatment with albuterol (12 +/- 32 L/min) than with placebo (-0.4 +/- 19 L/min; p less than 0.05). In addition, a clinically important level of improvement in PEFR (15 percent increase) was reached significantly more frequently in the responders. Methacholine nonresponders had no change in PEFR on either albuterol or placebo. Daily symptom scores as well as spirometry measurements at biweekly visits did not show significant changes. We conclude that long-term therapy with inhaled albuterol improves lung function in CF patients, but only in those with bronchial hyperresponsiveness as demonstrated by methacholine challenge. Twenty-four hospitalized patients with cystic fibrosis were enrolled into a 2-d, double-blind, placebo-controlled, randomized crossover trial comparing albuterol inhalation aerosol with a saline placebo. Aerosols were administered with the first three of four chest physiotherapy sessions given 4 h apart. Spirometry was measured before and 45 min after 7:00 A.M. and 3:00 P.M. therapy and before therapy at 7:00 P.M. and 7:00 A.M. the next morning. The mean percent change in FVC, FEV1, and FEF25-75% at 7:00 A.M. was 10.7, 14.8, and 19.6% with albuterol versus 2.4, 1.0, and -0.8% with placebo (p = 0.0012, < 0.0001, and = 0.003, respectively). A greater than 8% change in FEV1 separated changes with albuterol versus placebo with 96% specificity and occurred in 75% of all patients with albuterol; 71% at 7:00 A.M. versus 24% at 3:00 P.M. The reduction in response at 3:00 P.M. (p < 0.01) was presumably due to prolonged effects of morning therapy ( > 4 h). Individual changes in spirometry were significantly more positive and homogeneous with albuterol versus placebo at both 7:00 A.M. and 3:00 P.M. The mean percent change for the FVC, FEV1, and FEF25-75 across the day (7:00 A.M. pretherapy to 7:00 P.M. pretherapy) was 8.1, 10.1, and 9.7% with albuterol versus 3.9, 3.5 and 2.6% with placebo (p = 0.029, 0.036, and 0.232, respectively). The more positive and homogeneous changes in spirometry with albuterol, along with greater changes in these measures across the day when compared with placebo, suggest that albuterol improves pulmonary function in a majority of hospitalized patients with cystic fibrosis. Sleep-related oxygen desaturation has been described in patients with cystic fibrosis (CF). Thus we studied the effects of inhaled Salmeterol xinafoate, a long-acting beta-2 agonist, on transcutaneous oxyhemoglobin saturation in sleeping, stable CF patients. Patients with stable CF (n = 23) were divided into responders and nonresponders to beta-2 agonists, based on an albuterol challenge during daytime testing, and then they received salmeterol before sleep, in a double-blind crossover design. Overnight oxyhemoglobin saturation measurements and spirometry on awakening were performed. Salmeterol administration before sleep resulted in statistically significant increases in mean arterial oxyhemoglobin saturation and in FEV(1) and FEF(25-75) on awakening compared to placebo values, but only in patients responding to daytime albuterol inhalation by showing improvement in lung function. We conclude that salmeterol inhalation at bedtime could prevent or reduce nocturnal hypoxemia in daytime albuterol-responsive CF patients, thus improving the long-term clinical outcome of CF lung disease.
                Copyright 2002 Wiley-Liss, Inc. Inhaled, short-acting beta-adrenergic agonists (SAbetaAs) are widely prescribed in cystic fibrosis (CF) subjects, despite a lack of convincing data for efficacy and the potential for these agents to result in airway instability. We tested the hypothesis that inhaled albuterol would improve maximal exercise performance in CF subjects with airflow obstruction, as a result of acute bronchodilation.
                Randomized, double-blind, placebo-controlled crossover study of the effect of inhaled albuterol on maximal exercise performance in 20 stable adult CF patients (mean +/- SD age, 23.3 +/- 6.1 years; FEV(1), 57.65 +/- 17.13% of predicted).
                Ventilatory limitation to exercise was demonstrated in 16 subjects (80%). Significant bronchodilation occurred with exercise alone (end-exercise FEV(1), 2.24 +/- 0.8 L; vs preexercise FEV(1), 2.09 +/- 0.77 L; p < 0.0001), but albuterol resulted in significantly greater exercise-induced bronchodilation than placebo (change in FEV(1), 0.3 +/- 0.15 L vs 0.15 +/- 0.11 L; 95% confidence interval [CI], + 0.07 to + 0.23; p < 0.001). However, there was no difference in maximal workload achieved (albuterol, 158 +/- 46 W; vs placebo, 158 +/- 45 W; 95% CI, - 4.41 to + 4.71; p = 0.95), nor any other measure of exercise performance including maximal oxygen uptake.
                Despite causing significant acute bronchodilation, inhaled albuterol did not improve maximal exercise performance in ventilatory-limited CF adults, adding to the body of literature that fails to show any clinical benefit of SAbetaAs in CF subjects. The current results provide further evidence to question the widespread use of these agents, although the potential for adrenergic beta-agonists to instead improve submaximal exercise performance merits further investigation. A proportion of patients with cystic fibrosis (CF) suffer from increased airway hyperreactivity but their response to bronchodilators is variable. Adrenergic agents may produce an increase, no change or a decrease in forced expiratory volume in 1 second (FEV1). We hypothesized that the variable response might be related to poor aerosol distribution caused by the presence of secretions. Therefore, in 11 children with CF and airway hyperreactivity the influence of pretreatment with either 0.9% saline, salbutamol, or ipratropium bromide on the methacholine challenge test was evaluated in a double-blind, randomized, cross-over study. FEV1 (mean +/- S.E.) did not change following pretreatment with saline, salbutamol, or ipratropium (1.64 +/- 0.22, 1.63 +/- 0.16 and 1.67 +/- 0.19, respectively). All patients demonstrated airway hyperreactivity with a PC20 below 8 mg/mL (geometric mean, 0.41 mg/mL) after saline pretreatment. Salbutamol inhalation significantly increased the PC20 to 1.24 mg/mL (P less than 0.01), but ipratropium bromide was found to be even more effective than salbutamol (PC20 = 7.37 mg/mL) (P less than 0.0001). We conclude that the variable response to bronchodilator is not secondary to impaired aerosol distribution since ipratropium bromide effectively blocked the response to methacholine. The improvement in PC20 without a change in baseline FEV1 following salbutamol suggests that the adrenergic agent altered the contractile mechanism of smooth muscle. The effect of large doses of salbutamol (S) and ipratropium bromide (IB) were tested in a double-blind, randomized, crossover study. Nine patients with cystic fibrosis (CF), aged 12.8 +/- 2 years (mean +/- SE), were studied for 8 h on 2 separate days. Pulmonary function tests (PFTs) included spirometry (FEV1), lung volumes (FRC), and airway resistance (Raw) measured by body plethysmography. Heart rate (HR) and oxygen saturation (SaO2) were measured before each test. On 1 day patients received S 200 micrograms, S 400 micrograms, and IB 80 micrograms, by inhalation at 45-min interval (sequence A). On the other day, the sequence was IB 80 micrograms, S 200 micrograms, and S 400 micrograms (sequence B). The PFTs were obtained at baseline, 45 min after each inhalation, and 4 and 8 h after baseline measurements. Baseline PFTs (mean +/- SE) were not significantly different on the 2 study days (FEV1, 1.48 +/- 0.1 vs 1.42 +/- 0.1 L; FRC, 2.77 +/- 0.6 vs 2.87 +/- 0.6 L; Raw, 4.04 +/- 0.2 vs 4.00 +/- 0.3 cm H2O/L/s). The FEV1 and Raw improved from baseline after each inhalation, and at 4 and 8 h during both days (p < 0.05). Forty-five minutes after S 200 micrograms, plus S 400 micrograms, FEV1, FRC, and Raw were not significantly different compared with the values 45 min after IB 80 micrograms, plus S 200 micrograms (1.67 +/- 0.1 vs 1.63 +/- 0.1 L; 2.81 +/- 0.6 vs 2.65 +/- 0.5 L; and 2.98 +/- 0.2 vs 2.66 +/- 0.1 cm H2O/L/s, respectively). The PFTs were not significantly different after maximal doses of IB (80 micrograms) compared with S (600 micrograms). The HR and SaO2 were not significantly different from baseline throughout the study period. These results indicate that both single and sequential therapy have a similar acute bronchodilator effect provided that large doses are used. We speculate that adrenergic and muscarinic pathways are equally important in airflow obstruction in patients with CF.
It was not possible to determine fully the effectiveness of inhaled bronchodilators in CF as a meta-analysis was not possible. However, short and long-acting beta-2 agonists can be beneficial both in the short and long term in individuals with demonstrable bronchodilator responsiveness or bronchial hyper-responsiveness. As we found no evidence, the use of fenoterol, formoterol or tiotropium in CF cannot be supported.