Letters

Higher dose inhaled steroids in childhood asthma

Conventional doses do have side effects

Why isn't titration advocated more often in delivery of inhaled drugs?

Conventional doses do have side effects

EDITORWe disagree with Keeley's assertion that in childhood asthma "important adverse effects are rare" with inhaled corticosteroids at doses of 400 µg/day (beclomethasone equivalent).¹ Growth suppression is the most important side effect of inhaled corticosteroids in childhood, and all three preparations licensed for use in children in the United Kingdom cause appreciable suppression at these doses. A recent meta-analysis reported growth suppression of 1.51 cm/year in children receiving beclomethasone and 0.42 cm/year for fluticasone,² and the child asthma management programme (CAMP) study showed growth suppression of 1.1 cm/year with budesonide.³

We agree with Keeley's suggestion that higher doses of inhaled corticosteroids than are currently advocated are needed to affect acute episodes, but we would advise caution. It is likely that the growth suppression is relatively short lived ^{3 4} and that growth thereafter readjusts to baseline. Consequently, repeated short courses of high dose inhaled corticosteroids could have a comparatively larger effect on growth than lower doses. It remains important to balance the beneficial and detrimental effects of any treatment in childhood.

Hayley Archer, specialist registrar. 
Kate Creese, specialist registrar. 
Iolo Doull, consultant respiratory paediatrician. 
Doullij{at}cf.ac.uk Cystic Fibrosis/Respiratory Unit, University Hospital of Wales, Cardiff CF14 4X

Competing interests: HA and KCnone declared. ID has received payment for educational lectures and for attending conferences from GlaxoSmith- Kline; AstraZeneca; Merck, Sharp and Dohme; 3M; and Fisons. He has also received research funds and consulting fees from GlaxoSmithKline.

Why isn't titration advocated more often in delivery of inhaled drugs?

EDITORIn his editorial Keeley has highlighted an anomaly that has puzzled me for years: why is titration not advocated more often in the delivery of inhaled drugs in acute asthma exacerbations?¹

As Keeley points out, the delivery of inhaled treatment in a particular child (or adult) with acute asthma will be influenced by the delivery method used and by the degree of constriction in his or her airways during the exacerbation. It is logical to approach the uncertainty of response to treatment by giving frequent doses at short intervals and monitoring the response.

This technique has been used extensively in randomised trials to overcome the uncertain ratio of  agonist that is delivered to the airways (in contrast to the amount of drug emitted by the delivery device). Intervals between delivery have varied and range from 10 to 60 minutes. Equivalent benefits have been found with both nebulised delivery and metered dose inhaler with a spacer device (in the latter case using four to six separate actuations of the inhaler inhaled one at a time over a few minutes).² The trials have mostly been carried out in emergency departments, usually with the concurrent administration of oral steroids; the few patients who did not respond to repeated treatments after two hours were admitted to hospital.

Personal experience over the past two years has shown that such an approach can work well in primary care for inhaled  agonists in adults and children (for all but the most severe exacerbations). I now tend to use four puffs of a  agonist via metered dose inhaler given through a spacer device every 10 minutes; most exacerbations respond well within about half an hour. I routinely also use oral steroids for such attacks,³ but I agree that we need a trial of a titrated approach for inhaled steroids in the community, as the best doses, intervals, and delivery methods for inhaled steroids are not yet clear.

Christopher Cates, general practitioner. 
Manor View Practice, Bushey, Hertfordshire WD23 2NN chriscates{at}emailmsn.com

Competing interests: None declared.