Inhaled corticosteroids for asthma: on-demand or continuous use

Abstract

Continuous inhaled corticosteroid treatment is highly effective in children and adults with mild persistent asthma, although some therapeutic benefits are not lost if treatment is delayed. Many patients do not adhere to continuous treatment with inhaled corticosteroids, but rather take them intermittently, usually at the time of increased symptoms. Based on these observations it has been proposed that for patients with mild persistent asthma inhaled corticosteroids should be used on-demand when symptoms are troublesome, rather than on a continuous basis. The article reviews the pharmacological properties of inhaled corticosteroids used in clinical trials of on-demand treatment, as well as the evidence for the efficacy and safety of on-demand compared with continuous inhaled corticosteroid treatment of mild persistent asthma in adults and children. The place of on-demand treatment with inhaled corticosteroids in the management of asthma is discussed, as well as future directions for different management strategies for this group.

Keywords::

• anti-inflammatory
• asthma
• beclomethasone
• budesonide
• budesonide Turbuhaler®
• hydrofluoroalkane
• HFA-BDP Clenil® Modulite®
• HFA-BDP Qvar®
• inhaled corticosteroid

Financial & competing interests disclosure

NC Thompson has participated in advisory boards and/or received consultancy fees from Asmacure, Boston Scientific, Chiesi, Genentech and Respivert. NC Thompson has received lecture fees from AstraZeneca, Chiesi, GlaxoSmithKline, Novartis; industry-sponsored grant funding to the University of Glasgow from Aerovance, Asthmatx, AstraZeneca, Genentech, GlaxoSmithKline, MedImmune, Novartis and Synairgen for participating in clinical trials. M Spears has received lecture fees from AstraZeneca and Chiesi and industry grant funding from Genentech. The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Based on the observations that the benefits of regular inhaled corticosteroids on lung function are not lost if treatment is delayed and that many patients do not adhere to continuous treatment with inhaled corticosteroids, but rather take them intermittently, it has been proposed that inhaled corticosteroids should be used on-demand, when asthma symptoms are troublesome, rather than on a continuous basis.

• • The inhaled corticosteroids used to date in clinical trials of continuous versus intermittent dosing strategies are budesonide and beclomethasone. Budesonide is deposited mainly in the large airways whereas extrafine-particle inhaled beclomethasone have greater lung deposition including the small airways. It has not been clearly demonstrated that equipotent doses of small-particle inhaled corticosteroids compared with large-particle inhaled corticosteroids either improve efficacy or reduce systemic adverse effects.

• • Clinical trials to date comparing on-demand with continuous inhaled corticosteroid in adults and children with asthma suggest that the efficacy of the on-demand strategy is similar or less than continuous treatment whereas adverse effects in children may be greater with continuous treatment although it is uncertain whether this is relevant in mild persistent asthma where the total dose of inhaled corticosteroid administered are usually low.

• • Patient preference is an important factor in deciding the most appropriate treatment options. Many patients do not adhere to regular treatment with inhaled corticosteroids and may prefer the on-demand inhaled corticosteroid strategy and to step-up treatment at the time of increased symptoms.

• • There is a need for large long-term studies in adults with asthma and in school-age and pre-school age children with asthma that compare the on-demand and continuous inhaled corticosteroid strategies to establish whether the options are equivalent in efficacy and safety.

• • With the development of a personalized approach to the treatment of asthma, future research will need to determine whether subgroups of patients can be identified by physiological, inflammatory and or genetic biomarkers that can predict those patients who are suited for continuous therapy or the on-demand option.

Notes