When asthma is inadequately controlled with inhaled corticosteroids, either adding medication such as long-acting beta2-agonists (LABAs) or increasing the dose of inhaled corticosteroids is recommended. The purpose of this review was to establish the benefits and safety of adding long-acting beta2-agonists or increasing the dose of inhaled corticosteroids in patients with asthma that is inadequately controlled on their current dose of inhaled corticosteroids. This review analysed data from identified randomised controlled trials comparing the addition of long-acting beta2-agonists to inhaled corticosteroids versus increasing to a higher dose of inhaled corticosteroids in asthmatic children and adults.
Based on the identified trials:
1. There is a modest advantage in adding long-acting beta2-agonists to inhaled corticosteroids, compared with increasing the dose of inhaled corticosteroids, in preventing exacerbations but many patients (more than 70) need to be treated for one to have an exacerbation prevented. The results apply particularly to adults, as no group differences were observed in children. Reduction in symptoms and use of rescue beta2-agonists as well as improvement in lung function tests also slightly favour the combination of long-acting beta2-agonists to inhaled corticosteroids over a higher corticosteroid dose.
2. Apart from an increased rate of tremor and less oral thrush, there is no apparent difference in the risk of side effects or rates of withdrawal from treatment because of side effects between the treatment options, but the long-term side effects of inhaled corticosteroids were seldom monitored. However, the trends towards an increased risk of moderate and severe exacerbations in children receiving combination therapy raises concern about this therapy, particularly in view of the modest improvement shown.