The effect of regular salbutamol on lung function and bronchial hyperresponsiveness in normal subjects and nonasthmatic atopic subjects with allergic rhinitis

The effect of regular salbutamol on lung function and bronchial responsiveness in patients with primary ciliary dyskinesia

STUDY OBJECTIVE

There is growing evidence that regular beta(2)-agonist use in patients with asthma is associated with decreased airway caliber and increased bronchial responsiveness. The aim of this study was to determine whether regular treatment with beta(2)-agonists induces changes in lung function and bronchial responsiveness in patients with primary ciliary dyskinesia.

DESIGN

A randomized, double-blind, placebo-controlled, crossover study.

PATIENTS

Nineteen children with primary ciliary dyskinesia.

INTERVENTIONS

Subjects received inhaled salbutamol or identical placebo (2 x 100 microg qid) for periods of 6 weeks with a wash-out period of 4 weeks.

MEASUREMENTS AND RESULTS

FEV(1) was measured before and 3 weeks and 6 weeks after salbutamol or placebo treatment. High-dose methacholine inhalation tests were performed before and 6 weeks after each treatment. The provocative concentration of methacholine producing a 20% fall in FEV(1) (PC(20)) and maximal airway narrowing (MDeltaFFEV(1)) was measured. No significant change in FEV(1) was observed during the salbutamol or placebo periods. No significant differences in the parameters of bronchial responsiveness (PC(20) and MDeltaFFEV(1)) were noted as the result of either salbutamol or placebo treatment.

CONCLUSION

Our data have shown that salbutamol, inhaled regularly for 6 weeks, did not cause either a decline in lung function or an increase in bronchial responsiveness in subjects with primary ciliary dyskinesia.

Inhaled short acting beta2-agonist use in asthma: regular vs as needed treatment

BACKGROUND

Inhaled beta2-adrenergic agonists delivered by inhalation are very widely used in asthma. There has been much controversy of the use and possible consequences of the use of these agents for regular, as opposed as-needed use in asthma.

OBJECTIVES

This review to assessed the clinical trial evidence to test whether using regular use of short-acting beta2-agonists reduced asthma control and pulmonary function; worsened symptoms, airway reactivity and quality of life; and increased the rate of exacerbations.

SEARCH STRATEGY

A search was carried out of the Cochrane Airways Group "Asthma and Wheez* RCT" register using the terms: regular AND [beta agonist OR bronchodilator OR salbutamol OR albuterol Or terbutaline OR isoproterenol OR reproterol OR fenoterol]. Bibliographies of existing trials were searched and primary trial authors and pharmaceutical companies were approached for additional trials.

SELECTION CRITERIA

Randomised controlled trials in which the short-acting beta2-agonist was given regularly in the experimental group, together with an inhaled bronchodilator for relief of symptoms ('rescue use'). The control group consisted of matching placebo inhaled regularly, with an inhaled bronchodilator for as-needed 'rescue use'.

DATA COLLECTION AND ANALYSIS

Data were extracted and quality assessments were made by both reviewers. Parallel group and cross-over trials were analysed separately. Where possible data were pooled using a fixed effects model.

MAIN RESULTS

Over 800 abstracts were identified, following a review, 60 papers were requested for full assessment by both reviewers. 34 trials from 30 papers met the entry criteria. Data from 31 outcomes were analyzable. There was little difference between the treatments for nearly all outcomes. In cross-over studies, evening peak flow was better with regular treatment, weighted mean difference (WMD) 13.1 l/min (95% confidence interval 24.3, 1.9). In contrast, the FEV1 was better with as-needed treatment (WMD 157 ml (95% CI: 123, 192). Bronchial hyper reactivity was slightly better in the as-needed group, standardised mean difference 0.23, 95% CI: 0.52, 1.12.

REVIEWER'S CONCLUSIONS

These results support current guidelines. There is little advantage in using short-acting beta2-agonists regularly, and potentially some small clinical disadvantage.