Beclomethasone dipropionate dry-powder inhalation compared with conventional aerosol in chronic asthma.

In a double-blind study beclomethasone dipropionate inhaled as a dry powder in doses of 100 microgram four times daily and 150 microgram four times daily was compared with the conventional aerosol dose of 100 microgram four times daily in 20 outpatients with chronic asthma. Each of the three treatments was given for four weeks. The dry powder in a dose of 150 microgram four times daily had advantages over the other two treatments in terms of FEV1 and the number of exacerbations of asthma during the study. There were no adverse reactions to inhaling dry-powder beclomethasone. It was concluded that this new way of administering the drug was effective in chronic asthma, and should allow most patients with chronic asthma who cannot use conventional pressurised aerosols efficiently to benefit from inhaled corticosteroid treatment.     

Local Effect of Intranasal Beclomethasone Dipropionate Aerosol in Hay Fever

The effect of a daily dose of 400 μg beclomethasone dipropionate aerosol intranasally has been investigated in a double-blind cross-over trial in 29 patients with hay fever. The effect on the nasal symptoms was so pronounced in 25 patients that further symptomatic treatment was unnecessary. Beclomethasone dipropionate aerosol had, on the other hand, no direct effect on itching in the eyes, which is in accordance with the fact that biochemical investigations did not show any sign of suppression of the adrenal function. It is concluded that beclomethasone dipropionate aerosol intranasally is an effective and apparently harmless way of controlling the nasal symptoms in hay fever.     

Effect of inhaled endotoxin on bronchial reactivity in asthmatic and normal subjects

Endotoxins are released from the membrane of Gram-negative bacteria present in the environment and in oral and nasal cavities. They are proinflammatory substances that could participate in bronchial obstruction and hyperreactivity in asthmatic patients. This hypothesis was tested by using bronchial challenge tests with inhaled lipopolysaccharides (LPS) from Escherichia coli 026:B6 (22.2-micrograms total dose) followed by a histamine nonspecific challenge test and compared with a placebo procedure, in which the diluent was substituted for the LPS solution. In doing so we showed that LPS induces a slight but significant (P less than 0.01) bronchial obstruction (measured as forced expiratory volume in 1 s) in asthmatics (n = 8) but not in normal subjects (n = 6). The histamine hyperresponsiveness, expressed as the dosage of histamine necessary to decrease the bronchial specific conductance by 50%, was increased 5 h after LPS inhalation in asthmatics (P less than 0.05) but not in normal subjects. This effect of LPS on bronchial obstruction and hyperresponsiveness was observed in extrinsic (n = 6) as well as in intrinsic (n = 2) asthma.     

Substitution of inhaled beclomethasone dipropionate for ingested prednisone in steroid-dependent asthmatics

The effect of inhaled beclomethasone dipropionate (dose, 400 μg daily) was investigated in 31 prednisone-dependent asthmatics. In a double-blind noncrossover study of 25 patients dependent on a daily prednisone dose of 17.5 mg or less, the dose of ingested prednisone was significantly diminished through the use of beclomethasone as compared with placebo (P < 0.001). In a subsequent single-blind study of the 12 patients who had received placebo, a similar decrease in prednisone dose was possible when these patients received beclomethasone. In all 25 patients the effect of beclomethasone was maintained for 2 years; 9 came to require less beclomethasone and 1 required more. In an additional single-blind study of six patients with severe asthma, dependent on prednisone in a dose of 20 to 25 mg/d, the response to beclomethasone was more variable and less significant (P < 0.01). However, at 2 years there was no significant benefit (P > 0.05) and there were two treatment failures.In patients in whom reduction of dose or discontinuation of prednisone was possible plasma cortisol values before and after corticotropin administration increased significantly (P < 0.001). Prednisone reduction was associated with the appearance of mild musculoskeletal steroid-withdrawal symptoms of short duration in 15 patients, and recurrence of symptoms of rhinitis in 15 patients. Side effects of beclomethasone included episodes of hoarseness in 6 and easily treated oropharyngeal Candida albicans infection in 14.     

Arthropod-derived histamine-binding protein prevents murine allergic asthma

Because histamine receptor type I blockade attenuates allergic asthma, we asked whether complete neutralization of histamine by an arthropod-derived, high affinity histamine-binding protein (EV131) would prevent allergic asthma. Intranasal administration of EV131 given before Ag challenge in immunized mice prevented airway hyperreactivity by 70%, and abrogated peribronchial inflammation, pulmonary eosinophilia, mucus hypersecretion, and IL-4 and IL-5 secretion. Saturation with histamine abrogated the inhibitory effect of EV131 on bronchial hyperreactivity. The inhibitory effect of EV131 on bronchial hyperreactivity was comparable to that of glucocorticosteroids. These results demonstrate that histamine is a critical mediator of allergic asthma. Therefore, complete neutralization of histamine, rather than specific histamine receptor blockade, may have a profound effect on allergic asthma.     

Induction of drug-metabolizing enzymes and transporters in human bronchial epithelial cells by beclomethasone dipropionate

Inhaled steroids are the most potent anti-inflammatory therapy commonly used in bronchial asthma. There are, however, a small number of asthmatic patients who do not respond to inhaled steroid-treatment. The stimulation of metabolism and excretion of inhaled drugs at bronchial tissues might lead to a decrease in the effect of the drugs, although the molecular mechanism of this resistance is unclear. In this study, we found that beclomethasone dipropionate (BDP) stimulated the expression of mRNAs for uridine 5'-diphosphate glucuronosyl transferase 2B4 and 2B11, and transporters such as multidrug resistance P-glycoprotein, multidrug resistance-associated protein 1 and 2 in cultured bronchial epithelial cells. It is possible that the individual differences of expression of drug metabolizing enzymes and transporters and their enhancement with BDP are implicated in the individual differences of reactivity over steroid medical treatment.     

Airway reactivity in ponies with recurrent airway obstruction (heaves)

We measured lung function and airway reactivity to histamine administered by aerosol in two groups of ponies. Principal ponies had a history of heaves, a disease characterized by recurrent airway obstruction when ponies are housed in a barn and fed hay; control ponies had no history of airway obstruction. Ponies were paired (principal and control) and measurements were made when principal ponies were at pasture and in clinical remission (period A), following barn housing when principal ponies had acute airway obstruction (period B), and after a further 1 and 2 wk at pasture (periods C and D). At periods A, C, and D dynamic compliance (Cdyn), pulmonary resistance (RL), arterial O2 tension (PaO2), and CO2 tension (PaCO2) of principals and controls did not differ. Barn housing (period B) decreased Cdyn and PaO2 and increased RL in principals but not controls. The ED65Cdyn (the dose of histamine to reduce Cdyn to 65% of base line) did not differ in principals and controls at periods A, C, and D. At period B, ED65Cdyn decreased by 2.5-log doses of histamine in principals while ED65Cdyn was not affected in controls. There was no correlation between changes in airway reactivity and changes in RL and Cdyn. We conclude that ponies in clinical remission from heaves are not hyperreactive to histamine aerosol. This model of lung disease is similar to some forms of industrial asthma in which hyperreactivity occurs only during acute airway obstruction. The lack of correlation between ED65Cdyn and the degree of airway obstruction suggests that the hyperreactivity of principal ponies to histamine aerosol cannot be explained solely by alterations in baseline airway caliber.     

Bronchial reactivity to histamine before and after sodium cromoglycate in bronchial asthma.

Out of 19 patients with extrinsic bronchial asthma challenged with 123 mug histamine acid phosphate by intravenous infusion only 13 responded with a fall in FEV1 of over 10% (mean 16%). Seventeen of these patients were given histamine 2 mg/ml by aerosol, and all responded with a mean decrease in FEV1 of 37.8%. When challenged with allergen extract by aerosol the mean decrease in FEV1 was 37.5%. After 40 mg sodium cromoglycate 15 of the 17 patients showed significant protection against allergen challenge with a mean decrease in FEV1 of only 23.6%. Inhalation of 40 mg sodium cromoglycate, however, failed to protect against histamine given by either the intravenous or aerosol route. Histamine given intravenously to asthmatic patients produces less of a bronchial response than when given by aerosol, even though the intravenous route produces many more systemic symptoms, such as flushing and throbbing headache. The protection of sodium cromoglycate against an allergen inhalation challenge is not due to histamine antagonsim.     

Acute transient SO2-induced airway hyperreactivity: effects of nedocromil sodium

The effect of nedocromil sodium given as an aerosol on the immediate lung hyperreactivity and lung inflammation caused by a 2-h exposure to 400 ppm SO2 has been studied in dogs. Exposure to SO2 caused an immediate increase in bronchial responsiveness to histamine aerosol that lasted for approximately 2 h. The total number of cells recovered by bronchial lavage increased postexposure. Initially this increase was caused by epithelial cells (0.25 and 1 h) and later by neutrophils (1, 2, 3, and 4 h). There was no significant change in the numbers of lymphocytes, macrophages, eosinophils, goblet cells, or mast cells in the lavages. Nedocromil sodium (approximately 8 mg) given as a nebulized aerosol before and after SO2 exposure prevented the increase in lung reactivity and attenuated the increase in the total number of cells (epithelial cells and neutrophils) in the lung lavages for the 4 h after exposure. Nedocromil sodium did not affect the reactivity of normal dogs to histamine aerosol. Nedocromil sodium appears to act as an anti-inflammatory agent in this model of lung inflammation, preventing an increase in lung reactivity and reducing cell infiltration. The mechanism of action of nedocromil sodium in this model is unknown.     

Influence of sensitization and allergen provocation procedures on the development of allergen-induced bronchial hyperreactivity in conscious, unrestrained guinea-pigs

The effects of different sensitization and allergen provocation regimens on the development of allergen-induced bronchial hyperreactivity (BHR) to histamine were investigated in conscious, unrestrained guinea-pigs. Similar early and late phase asthmatic reactions, BHR for inhaled histamine after the early (6 h) as well as after the late reaction (24 h), and airway inflammation were observed after a single allergen provocation in animals sensitized to produce mainly IgG or IgE antibodies, respectively. Repeating the allergen provocation in the IgE-sensitized animals after 7 days, using identical provocation conditions, resulted in a similar development of BHR to histamine inhalation. Repetition of the allergen provocation during 4 subsequent days resulted in a decreased development of BHR after each provocation, despite a significant increase in the allergen provocation dose necessary to obtain similar airway obstruction. The number of inflammatory cells in the bronchoalveolar lavage was not significantly changed after repeated provocation, when compared with a single allergen provocation. Finally, we investigated allergen-induced bronchial hyperreactivity by repetition of the sensitization procedure at day 7 and 14 (booster), followed by repeated allergen provocation twice a week for 5 weeks. Surprisingly, no BHR to histamine could be observed after either provocation, while the number of inflammatory cells in the bronchoalveolar lavage fluid after 5 weeks was enhanced compared with controls. These data indicate that both IgE and IgG sensitized guinea-pigs may develop bronchial hyperreactivity after a single allergen provocation. Repeated allergen exposure of IgE sensitized animals causes a gradual fading of the induced hyperreactivity despite the on-going presence of inflammatory cells in the airways, indicating a mechanism of reduced cellular activation.     

Bronchial hyperreactivity to leucotriene D4 and histamine in exogenous asthma.

Reactivity of the small and large airways to inhaled leucotriene D4, one of the leucotrienes that constitute slow reacting substance of anaphylaxis, was studied in eight patients with exogenous asthma and nine healthy subjects with no history of atopy. Non-cumulative dose response relations were constructed for leucotriene D4 in a randomised, double blind set up. Reactivity to the leucotriene was compared with reactivity to histamine in the two groups. Both groups reacted to leucotriene D4 with significant airway obstruction evident in forced expiratory volume in one second (FEV1), peak expiratory flow rate, maximal expiratory flow rate at 30% of forced vital capacity estimated from a partial flow volume curve initiated at 50% of vital capacity (V30), and an increase in volume of trapped gas. The airways of the patients were significantly (p less than 0.01) more reactive to leucotriene D4 than those of the controls. The differences were in order of magnitude, 10(2)-10(3) for FEV1 but only about 15 for V30 (p less than 0.05). The hyperreactivity of the airways of the asthmatic subjects to leucotriene D4 was comparable to that to histamine. Inhalation of leucotriene D4 caused pronounced dyspnoea only among the patients. The findings suggest a role for leucotriene D4 in human bronchial asthma.     

Steroid Aerosols in Asthma: An Assessment of Betamethasone Valerate and a 12-month Study of Patients on Maintenance Treatment

Betamethasone valerate aerosol is a new compound for the treatment of asthma. Its clinical effectiveness was established in a double-blind cross-over trial in non-steroid-dependent asthmatic patients. At a dosage of 400 to 800 μg/day for three months there was no evidence of suppression of hypothalamic-pituitary-adrenal function, as assessed by tetracosactrin and insulin stress tests.A 12-month follow-up study of 120 patients using steroid aerosols (betamethasone valerate or beclomethasone dipropionate) indicated that tolerance does not develop and that a daily maintenance dose of 200 μg/day was adequate in most patients. Temporary lack of response was observed during episodes of sputum production or of heavy exposure to antigen.There were no observed side effects other than fungal infections of the respiratory tract. However, the incidence of candidiasis of the pharynx (13%) and particularly of the larynx (5%) in apparently immunologically normal patients was disturbing. These infections were not seen in patients taking 200 μg/day. Though there is yet no evidence that fungal infections associated with steroid aerosols may penetrate the trachea and bronchi the possibility of this indicates that caution should be exercised in their use, particularly in long-term high dosage.     

Effect of inhaled corticosteroids on episodes of wheezing associated with viral infection in school age children: randomised double blind placebo controlled trial.

OBJECTIVES: To determine the effect of regular prophylactic inhaled corticosteroids on wheezing episodes associated with viral infection in school age children. DESIGN: Randomised, double blind, placebo controlled trial. SETTING: Community based study in Southampton. SUBJECTS: 104 children aged 7 to 9 years who had had wheezing in association with symptoms of upper and lower respiratory tract infection in the preceding 12 months. INTERVENTIONS: After a run in period of 2-6 weeks children were randomly allocated twice daily inhaled beclomethasone dipropionate 200 micrograms or placebo through a Diskhaler for 6 months with a wash out period of 2 months. Children were assessed monthly. MAIN OUTCOME MEASURES: Forced expiratory volume in 1 second (FEV1); bronchial responsiveness to methacholine (PD20); percentage of days with symptoms of upper and lower respiratory tract infection with frequency, severity, and duration of episodes of upper and lower respiratory symptoms and of reduced peak expiratory flow rate. RESULTS: During the treatment period there was a significant increase in mean FEV1 (1.63 v 1.53 1; adjusted difference 0.09 1 (95% confidence interval 0.04 to 0.14); P = 0.001) and methacholine PD20 12.8 v 7.2 mumol/l; adjusted ratio of means 1.7 (1.2 to 2.4); P = 0.007) in children receiving beclomethasone dipropionate compared with placebo. There were, however, no significant differences in the percentage of days with symptoms or in the frequency, severity, or duration of episodes of upper or lower respiratory symptoms or of reduced peak expiratory flow rate during the treatment period between the two groups. CONCLUSIONS: Although lung function is improved with regular beclomethasone dipropionate 400 micrograms/day, this treatment offers no clinically significant benefit in school age children with wheezing episodes associated with viral infection.     

Comparison of Beclomethasone Dipropionate Aerosol and Prednisolone in Reversible Airways Obstruction

This paper describes a double-bond crossover trial of prednisolone and beclomethasone dipropionate aerosol in 38 steroid-dependent patients with reversible diffuse airways obstruction. Altogether there was no difference in the patient''s preference of the two treatment groups or in the number of times they used their bronchodilator aerosol, or in the forced expiratory volume in one second, vital capacity, or peak expiratory flow rate in the two treatment groups. The plasma cortisol levels when the patients were on the aerosol were much higher than when they were on prednisolone. The use of inhaled aerosol steroids seems to be preferable as it eliminates the usual complications of oral steroid therapy.     

Recovery of Adrenal Function after Substitution of Beclomethasone Dipropionate for Oral Corticosteroids

Of 16 steroid-dependent asthmatic patients oral treatment has been discontinued in six and reduced in four after the introduction of beclomethasone dipropionate. Substitution of inhaled beclomethasone for oral steroids was unsuccessful in the remaining six patients. Serial adrenal function studies in the patients whose oral treatment was discontinued showed progressive recovery, and five out of six had a normal response to tetracosactrin stimulation after two months.     

喘息的"度"与支气管哮喘阶梯治疗

目的:探讨掌握喘息"度"与支气管哮喘阶梯治疗的关系。方法:充分掌握支气管哮喘分级治疗方案和支气管哮喘病情,将喘息"度"细致化,与分级治疗用药"度"密切结合起来,对于完全理想的控制哮喘将会起到极大的指导作用,对于升阶梯和降阶梯治疗都会起到重要而细致的指导作用。必须将平喘治疗措施置于患者全身病情变化及总体治疗之下,会取得更加理想的哮喘控制效果。而强化支气管哮喘患者教育在支气管哮喘理想治疗中占据极为重要的地位,甚至直接关系到哮喘控制的持久性和稳定性。应得到高度重视。结果:喘息"度"与支气管哮喘的发作程度密切相关,准确把握并分级十分重要。结论:准确把握喘息"度"并与支气管哮喘分级治疗方法结合,将对稳定平息支气管哮喘起到意想不到的效果。     

Inflammatory cell distribution in guinea pig airways and its relationship to airway reactivity.

Although airway inflammation and airway hyperreactivity are observed after allergen inhalation both in allergic humans and animals, little is known about the mechanisms by which inflammatory cells can contribute to allergen-induced airway hyperreactivity. To understand how inflammatory cell infiltration can contribute to airway hyperreactivity, the location of these cells within the airways may be crucial Using a guinea pig model of acute allergic asthma, we investigated the inflammatory cell infiltration in different airway compartments at 6 and 24 h (i.e. after the early and the late asthmatic reaction, respectively) after allergen or saline challenge in relation to changes in airway reactivity (AR) to histamine. At 6 h after allergen challenge, a threefold (p < 0.01) increase in the AR to histamine was observed. At 24 h after challenge, the AR to histamine was lower, but still significantly enhanced (1.6-fold, p < 0.05). Adventitial eosinophil and neutrophil numbers in both bronchi and bronchioli were significantly increased at 6 h post-allergen provocation as compared with saline (p < 0.01 for all), while there was a strong tendency to enhanced eosinophils in the bronchial submucosa at this time point (p = 0.08). At 24h after allergen challenge, the eosinophilic and neutrophilic cell infiltration was reduced. CD3+ T lymphocytes were increased in the adventitial compartment of the large airways (p < 0.05) and in the parenchyma (p < 0.05) at 24h post-allergen, while numbers of CD8+ cells did not differ from saline treatment at any time point post-provocation. The results indicate that, after allergen provocation, inflammatory cell numbers in the airways are mainly elevated in the adventitial compartment. The adventitial inflammation could be important for the development of allergen-induced airway hyperreactivity.     

ACE-inhibitors and defence reflexes of the airways.

The group of angiotensin-converting enzyme (ACE) inhibitors is one of the drugs of choice for the treatment of hypertension and congestive heart disease. However, it has been reported that in some of patients ACE-inhibitors induce hyperreactivity of the airways with occurrence of a persistent dry cough, dyspnoe and wheezing. We supposed that the mechanism of these hyperreactivity is connected to accumulation of bradykinin, tachykinins and other inflammatory mediators in the airways. Increased local concentration of inflammatory neuropeptides stimulates bronchial C fibres and rapidly adapting receptors and provoke the cough reflex. Inflammatory processes in the airways could be followed by contraction of airway smooth muscle. In this study, our aim was to measure the changes of the number and intensity of mechanical induced cough in cats, which were treated for days with enalapril (5 mg/kg b.w.). After 15 days of treatment the reactivity of the lung and tracheal smooth muscles to the bronchoconstrictor mediator histamine was estimated. As to our finding 15 days of administration of enalapril results in significant increase of cough parameters measured with a more significant sensitivity of the laryngopharyngeal part. In the experimental animals we observed increased reactivity of bronchial smooth muscle to histamine after 15 days of enalapril treatment. The reactivity of the lung smooth muscle to the histamine was not significantly changed. These results confirmed the increased cough sensitivity and increased bronchial reactivity after enalapril treatment. These experimental animal model may be useful for the investigation of the pharmacological minimization of respiratory adverse effect of ACE-inhibitors.     

May nasal hyperreactivity be a sequela of recurrent common cold?

Respiratory viral infections may worsen bronchial hyperreactivity. However, there is no data on the possible role of recurrent infectious rhinitis in nose hyperreactivity. This study was therefore designed to investigate whether subjects suffering from recurrent common cold have nasal hyperreactivity, assessed by histamine nasal challenge. This study included a group of 40 patients (19 males, mean age 34.1 years) with history of at least five episodes of common cold in the previous year, but without documented allergy, and twenty healthy subjects (8 males, mean age 32.3 years) were enrolled as control group, all of whom were non-allergic. Nasal provocation test with histamine was performed in all subjects. Nasal provocation test with histamine induced a 200% increase in nasal resistance after provocation in 24 (60%) patients suffering from recurrent viral rhinitis. No normal subject had an increase >180% in nasal resistance. There was a significant difference between the patient group and the control group (p<0.05). In conclusion, this study shows that nasal hyperreactivity might be a sequela of recurrent common cold. Further studies should be conducted to confirm this preliminary finding.     

Effects of histamine on bronchial artery blood flow and bronchomotor tone

The effects of aerosolized 5% histamine (10 breaths) on bronchial artery blood flow (Qbr), airflow resistance (RL), and pulmonary and systemic hemodynamics were studied in mechanically ventilated sheep anesthetized with pentobarbital sodium. Histamine increased mean Qbr and RL to 252 +/- 45 and 337 +/- 53% of base line, respectively. This effect was significantly different from base line for 30 min after challenge. The histamine-induced increase in RL was blocked by pretreatment with the histamine H1 receptor antagonist, chlorpheniramine, whereas the histamine-induced elevation in Qbr was prevented by the H2 antagonist, metiamide. Both responses were blocked only when both antagonists were present. Changes in Qbr were not directly associated with alterations in systemic and pulmonary hemodynamics or arterial blood gas composition. In vitro histamine caused a dose-dependent contraction of ovine bronchial artery strips that was prevented by H1 antagonist. The H2 agonist, impromidine, caused relaxation of precontracted arterial strips and was more potent and efficacious than histamine, whereas H1 agonists failed to elicit a relaxant response. Thus these findings indicate that histamine aerosol induces a vasodilation in the bronchial vascular bed; histamine has a direct effect on Qbr that is independent of alterations in RL, systemic and pulmonary hemodynamics, or arterial blood gas composition; and, histamine-induced bronchoconstriction is mediated predominantly by H1-receptors, whereas increased Qbr is controlled predominantly by H2-receptors, probably located in resistance vessels. This local effect of histamine on Qbr may have important implications in the pathophysiology of bronchial asthma and pulmonary edema.