Short-term regular beta 2-adrenergic agonists treatment is safe in mild asthmatics taking low doses of inhaled steroids. Inhaling beta(2)-agonist with heliox-driven in bronchial asthma. Cost effectiveness of leukotriene receptor antagonists versus long-acting beta-2 agonists as add-on therapy to inhaled corticosteroids for asthma: a pragmatic trial. Is the increase in bronchial responsiveness or FEV1 shortly after cessation of beta2-agonists reflecting a real deterioration of the disease in allergic asthmatic patients? A comparison between short-acting and long-acting beta2-agonists. Effects of the long acting beta agonist formoterol on asthma control in asthmatic patients using inhaled corticosteroids. The Netherlands and Canadian Formoterol Study Investigators. Repository dexamethasone in the treatment of acute bronchial asthma. Beta2-agonist tolerance and exercise-induced bronchospasm. Long-term effects of formoterol and salbutamol on bronchial hyperreactivity and beta-adrenoceptor density on lymphocytes in children with bronchial asthma. Effects of inhaled beclomethasone dipropionate on beta 2-receptor function in the airways and adrenal responsiveness in bronchial asthma.
Regular treatment with beta 2-adrenergic agonists is controversial in bronchial asthma. To investigate whether beta 2-adrenergic agonists can be used safely if associated with low doses of inhaled steroids, for a short period, without a deterioration of asthma control, we have examined 24 mild asthmatics. In a parallel, double-blind, placebo-controlled study, 1 week of run-in and run-out period framed 3 weeks of treatment. All patients received inhaled beclomethasone dipropionate (BDP 250 micrograms t.i.d.); after 1 week, 12 patients inhaled 400 micrograms of broxaterol and 12 patients received placebo t.i.d. FVC, FEV1, PD20-FEV1 methacholine, morning and evening PEF, and PEF amplitude % mean were measured before, during, and after treatment. No significant changes were noted in patients receiving inhaled broxaterol. There were no differences in symptoms and the use of rescue medication (salbutamol spray). We conclude that short-term regular treatment with beta 2-adrenergic agonists is not associated with a deterioration in asthma control in mild asthmatics inhaling low doses of steroids. To evaluate the effectiveness of a helium-oxygen mixture (79%He- 21%O(2)) as an aerosolizing compressed gas for beta(2)-agonist therapy in patients with an asthma exacerbation.
                Twenty-four patients in the outpatient department with a mild to moderate exacerbation of asthma were enrolled. The patients were randomly divided into an experimental group (13 cases) and a control group (11 cases). The experimental group inhaled Berotec with heliox-driven, and the control group inhaled Berotec with compressed air-driven. Eight hospitalized patients in the respiratory department with severe exacerbation of asthma were enrolled. The patients inhaled Berotec with heliox-driven or compressed air-driven in a random order.
                The results of spirometric parameters and arterial blood-gas analysis were measured. In the mild to moderate asthma patients, no statistical differences between the two groups for forced vital capacity (FVC), forced expired volume in one second (FEV(1)), and expiratory flow in 50% forced vital capacity (FEF(50)) were presented. But the severe patients showed significant differences between heliox-driven and compressed air-driven for FVC, FEV(1), FEF(50) and partial pressure of oxygen (PaO(2)).
                Compared with the traditional inhalation of beta(2)-agonist therapy using compressed air-driven, the method of inhaling beta(2)-agonist with heliox-driven has more obvious benefits for those suffering from severe asthma. This is likely due to the cooperative effects between inhaling heliox on its physical gas properties and improving delivery of beta(2)-agonist in the treatment of exacerbation of severe asthma. Information is lacking on the relative effectiveness and cost effectiveness--in a real-life primary-care setting--of leukotriene receptor antagonists (LTRAs) and long-acting beta2 adrenergic receptor agonists (beta2 agonists) as add-on therapy for patients whose asthma symptoms are not controlled on low-dose inhaled corticosteroids (ICS).
                To estimate the cost effectiveness of LTRAs compared with long-acting beta2 agonists as add-on therapy for patients whose asthma symptoms are not controlled on low-dose ICS.
                An economic evaluation was conducted alongside a 2-year, pragmatic, randomized controlled trial set in 53 primary-care practices in the UK. Patients aged 12-80 years with asthma insufficiently controlled with ICS (n = 361) were randomly assigned to add-on LTRAs (n = 176) or long-acting beta2 agonists (n = 185). The main outcome measures were the incremental cost per point improvement in the Mini Asthma Quality of Life Questionnaire (MiniAQLQ), per point improvement in the Asthma Control Questionnaire (ACQ) and per QALY gained from perspectives of the UK NHS and society.
                Over 2 years, the societal cost per patient receiving LTRAs was pounds sterling 1157 versus pounds sterling 952 for long-acting beta2 agonists, a (significant, adjusted) increase of pounds sterling 214 (95% CI 2, 411) [year 2005 values]. Patients receiving LTRAs experienced a non-significant incremental gain of 0.009 QALYs (95% CI -0.077, 0.103). The incremental cost per QALY gained from the societal (NHS) perspective was pounds sterling 22,589 (pounds sterling 11,919). Uncertainty around this point estimate suggested that, given a maximum willingness to pay of pounds sterling 30,000 per QALY gained, the probability that LTRAs are a cost-effective alternative to long-acting beta2 agonists as add-on therapy was approximately 52% from both societal and NHS perspectives.
                On balance, these results marginally favour the repositioning of LTRAs as a cost-effective alternative to long-acting beta2 agonists as add-on therapy to ICS for asthma. However, there is much uncertainty surrounding the incremental cost effectiveness because of similarity of clinical benefit and broad confidence intervals for differences in healthcare costs.
                UK National Research Register N0547145240; Controlled Clinical Trials ISRCTN99132811. Regular use of beta2-agonists might result in increased bronchial hyper-responsiveness (BHR) and decreased forced expiratory volume in 1 sec (FEV1). It has been suggested that these possible detrimental effects are not a real deterioration of the disease, but that it might be only a transient (rebound) effect shortly after discontinuing this regular use. Moreover, these effects are thought to occur especially during short-acting and not during long-acting beta2-agonists use. The aim of this study was to invest gate whether a rebound effect (a pharmacological deterioration effect diminishing after several hours) in FEV1 and PC20 (concentration of histamine causing a 20% fall in FEV1 with regard to baseline) occurred after cessation of regular use of beta2-agonists, and whether this occurred both after short-acting and long-acting beta2-agonists. Allergic asthmatic patients (n = 134) were randomly allocated to the use of a short-acting (salbutamol), a long-acting beta2-agonist (formoterol) or placebo for 12 weeks (double-blind, double-dummy). No other asthma medication was allowed, including inhaled corticosteroids. At the start and every 4 weeks later FEV and PC20 were measured, each time at least 12 h after the last doses of study medication, which is in the possible rebound period. To investigate whether a (transient) rebound effect occurred, parameters were additionally measured at least 72 h later after discontinuation of the study medication. After 12 weeks of short-acting beta2-agonist use, a drop was seen in FEV1 from 85.6 (+/- 2.21)% predicted to 78.8 (+/- 2.9)% predicted, measured 15 h (median) after the last doses of medication. This was significantly different compared to placebo. When measured 168 h (median) later FEV1 recovered to 85.5 (+/- 2.4)% predicted, comparable to baseline. PC20 decreased with -1.17 (+/- 0.44) doubling dose after 12 weeks of short-acting beta2-agonist use, measured 15 h after the last doses of medication, which was significantly different compared to placebo. However, 168 h later PC20 recovered slightly with +0.55 (+/- 0.34) doubling dose, but this value was still lower compared to placebo. In contrast, during long-acting beta2-agonist and placebo use no significant changes were seen. In conclusion, the use of short-acting beta2-agonists resulted in a transient (rebound) effect in FEV while the effects on PC20 may point to a real deterioration of the disease. Long-acting beta2-agonist and placebo use showed no changes. We conclude that a mono-therapy of short-acting and not of long-acting beta2-agonists might have deleterious effects in asthma. The long acting beta 2 agonist formoterol has proved to be an effective bronchodilator with a prolonged action of 12-14 hours. However, the precise role of formoterol in the maintenance treatment of asthma is still under debate. A study was performed to investigate the efficacy and safety of treatment with formoterol for six months in subjects with asthma.
                In a multicentre double blind, placebo controlled, parallel group study 239 subjects with mild to moderate asthma were randomly assigned to treatment with either inhaled formoterol 24 micrograms twice daily (n = 125) or placebo (n = 114) during eight months. The study consisted of a four week run in period, a 24 week treatment period, and a four week washout period. All subjects were using regular inhaled corticosteroids (100-3200 micrograms daily) but were still needing at least five inhalations of short acting beta 2 agonist per week for symptom relief. The study was performed in 10 outpatient clinics in Canada, and five outpatient clinics and one coordinating centre for 44 Dutch general practitioners in The Netherlands. Twice daily self-reported peak expiratory flow (PEF) measurements, symptom scores, and rescue beta 2 agonist use during the last 28 treatment days compared with baseline values were used as main outcome measures. Spirometric values were measured at entry, at the start of treatment, after four, 12 and 24 weeks of treatment, and after four weeks washout.
                One hundred and twenty five subjects received formoterol 24 micrograms twice daily via Turbohaler and 114 received placebo. Baseline FEV1 was 67.1% predicted and mean bronchodilator reversibility was 26%. The mean total asthma symptom score was 3.6 (maximum possible 21). A significant decrease in symptoms in favour of formoterol (difference from placebo -0.64, 95% CI -0.04 to -1.23, p = 0.04) was observed. Compared with placebo, morning PEF increased (difference from placebo 28 l/min, 95% CI 18.3 to 37.7, p = 0.0001) and the use of short acting beta 1 agonists decreased (daytime difference from placebo -1.1 inhalation, 95% CI -1.4 to -0.7, p = 0.0001) in the formoterol group. PEF returned to baseline following discontinuation of formoterol, as did asthma symptom scores. Thirty three patients treated with formoterol and 32 treated with placebo required treatment with prednisolone during the study (58 and 55 courses, respectively).
                Adding formoterol 24 micrograms twice daily by Turbohaler to inhaled corticosteroids was effective in improving symptom scores and morning PEF, and decreasing the use of rescue beta 2 agonists. There was no apparent loss of asthma control during 24 weeks of treatment with formoterol. Fifty-two patients with acute asthma requiring immediate therapy but not hospitalization were studied in an emergency department following conventional therapy with bronchodilators. After discharge, the patients were treated with a controlled regimen of long-acting theophylline and beta-agonist inhalation as necessary. They were randomly assigned to one of three groups using a double blind model. Group A received intramuscular and oral placebos. Group B received intramuscular dexamethasone injection along with oral placebo treatment. Group C received oral dexamethasone by a tapering schedule associated with placebo intramuscular injection. Follow-up was carried out 7 days after the treatment in the emergency room. There were no significant statistical differences in the relapse rate among the three groups. Those patients who received oral or intramuscular dexamethasone had a decrease in the need for beta-agonist inhalation and fewer respiratory symptoms. However, there was no significant statistical difference between groups B and C. It was concluded that repository steroids could reduce the respiratory symptoms and frequency of beta-agonist usage as effectively as oral steroid treatment. However, the steroids do not improve the relapse rate in patients with only mild symptoms. The effect of regular inhaled beta-agonist on the treatment of exercise-induced bronchoconstriction was studied. Eight subjects with exercise-induced bronchoconstriction took 1 week each of salbutamol 200 microg qid or placebo in a random-order, double-blind, crossover study. They then withheld this treatment for 8 hours before performing a dry-air, sub-maximal exercise challenge at a work-rate previously shown to induce a 15% fall in forced expiratory volume in 1 second (FEV1). Five minutes after exercise, they inhaled salbutamol 100, 100, and 200 microg at 5-minute intervals. The mean pre-exercise FEV1 was similar on both study days. However, pretreatment for 1 week with salbutamol led to a significantly greater fall in FEV1 after exercise. The FEV1 remained lower than during the placebo arm despite the administration of salbutamol after exercise. This difference persisted 25 minutes after exercise. It is concluded that regular beta-agonist treatment leads to increased exercise-induced bronchoconstriction and a suboptimal bronchodilator response to beta-agonist. The data suggest that previous regular beta-agonist treatment may lead to a failure to respond to emergency bronchodilator treatment during an acute asthma attack and support current opinion that regular short-acting beta-agonist therapy should not be used to treat asthma. Long-term treatment with short-acting beta 2-sympathomimetic drugs has recently been suggested to be due to a rise in asthma mortality. This effect has been attributed to an increase in bronchial hyperreactivity, a desensitization of beta 2-adrenoceptors and/or a rebound effect after cessation of the therapy. Formoterol, a new long-acting beta 2-symathomimetic drug, has been reported to possess not only bronchodilatation but also antiinflammatory effects. The aim of the present study was to investigate whether long-term effects of salbutamol and/or formoterol could deteriorate asthma management. Therefore, in a trial lasting 90 days, we evaluated the effects of the two drugs on lung function, on the protection they provided against inhalative provocation with histamine, and on tachyphylaxis as monitored by the beta-adrenergic density on mononuclear leukocytes (MNL). Two groups of 11 children each with stable asthma were treated with daily doses of either 4 x 200 micrograms salbutamol or 2 x 24 micrograms formoterol in monotherapy. The lung function was measured six times during the trial period, on day 1, and on day 90, before and after inhaling the drug and at all investigations both with and without histamine provocation. In both groups, the bronchodilatory effect of either formoterol or salbutamol remained constant. The lung function values before and after drug inhalation (specific airway resistance sRAW, forced expiration volume FEV1, vital capacity VC) did not alter significantly. After histamine provocation, the protection was more pronounced in the formoterol group. No changes in the beta-adrenoceptor density on MNL and no significant side effects were seen throughout the trial period. We therefore conclude that formoterol protects significantly better against the bronchial challenge with histamine than does salbutamol. Both drugs did not deteriorate the lung function in asthmatic children. In addition, there was no evidence that long-term treatment leads to a desensitization of beta 2-sympathomimetic effects. Sixteen patients suffering from bronchial asthma, with or without chronic bronchitis, sufficiently severe to be treated with inhaled corticosteroids, were studied in a single-blind trial (blind observer) of beclomethasone dipropionate (BDP) given in three randomized dosage regimens: 500, 1000 and 2000 micrograms per day, each for 4 weeks. The beta 2-adrenergic agonist response curve showed a dose-dependent increase in FEV1 which was not affected by different doses of BDP. A small but significant reduction in basal cortisol levels was observed after BDP 500 micrograms/day. There was no significant difference between the various doses of BDP in reducing cortisol level and stimulation with tetracosactide remained unchanged. The study showed a gradual, dose-dependent improvement in lung function, statistically significant for morning peak expiratory flow rate at BDP 2000 micrograms/day. Dyspnoea score and beta 2-agonist use decreased, reflecting the anti-asthmatic effects. An increase in total leukocyte count was observed, together with a decrease in the eosinophil count. Oral candidiasis was seen in 2 out of 16 patients. It is concluded that the clinical anti-asthmatic effects of corticosteroid treatment by inhalation are not due to modulation of beta 2-receptor function in the airways.
Long acting inhaled beta-agonists have advantages across a wide range of physiological and clinical outcomes for regular treatment.