How can we optimise inhaled beta2 agonist dose as 'reliever' medicine for wheezy pre-school children? Study protocol for a randomised controlled trial

Somnath Mukhopadhyay, Paul Seddon, Gemma Earl, Emma Wileman, Liz Symes, Cathy Olden, Corinne Alberti, Stephen Bremner, Alison Lansley, Colin N A Palmer, Nicole Beydon, Somnath Mukhopadhyay, Paul Seddon, Gemma Earl, Emma Wileman, Liz Symes, Cathy Olden, Corinne Alberti, Stephen Bremner, Alison Lansley, Colin N A Palmer, Nicole Beydon

Abstract

Background: Asthma is a common problem in children and, if inadequately controlled, may seriously diminish their quality of life. Inhaled short-acting beta2 agonists such as salbutamol are usually prescribed as 'reliever' medication to help control day-to-day symptoms such as wheeze. As with many medications currently prescribed for younger children (defined as those aged 2 years 6 months to 6 years 11 months), there has been no pre-licensing age-specific pharmacological testing; consequently, the doses currently prescribed (200-1000 μg) may be ineffective or likely to induce unnecessary side effects. We plan to use the interrupter technique to measure airway resistance in this age group, allowing us for the first time to correlate inhaled salbutamol dose with changes in clinical response. We will measure urinary salbutamol levels 30 min after dosing as an estimate of salbutamol doses in the lungs, and also look for genetic polymorphisms linked to poor responses to inhaled salbutamol.

Methods: This is a phase IV, randomised, controlled, observer-blinded, single-centre trial with four parallel groups (based on a sparse sampling approach) and a primary endpoint of the immediate bronchodilator response to salbutamol so that we can determine the most appropriate dose for an individual younger child. Simple randomisation will be used with a 1:1:1:1 allocation.

Discussion: The proposed research will exploit simple, non-invasive and inexpensive tests that can mostly be performed in an outpatient setting in order to help develop the evidence for the correct dose of salbutamol in younger children with recurrent wheeze who have been prescribed salbutamol by their doctor.

Trial registration: EudraCT2014-001978-33, ISRCTN15513131. Registered on 8 April 2015.

Keywords: Asthma; Children; Dose finding; Paediatric; Salbutamol; Wheeze.

Figures

Fig. 1
Fig. 1
CONSORT flowchart for the OpSal trial

References

    1. Raat H, Landgraf JM, Oostenbrink R, Moll HA, Essink-Bot ML. Reliability and validity of the Infant and Toddler Quality of Life Questionnaire (ITQOL) in a general population and respiratory disease sample. Qual Life Res. 2007;16:445–60. doi: 10.1007/s11136-006-9134-8.
    1. . Accessed 8 April 2015.
    1. Raat H, Bueving HJ, de Jongste JC, et al. Responsiveness, longitudinal- and cross-sectional construct validity of the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) in Dutch children with asthma. Qual Life Res. 2005;14:265–72. doi: 10.1007/s11136-004-6551-4.
    1. Hambleton G, Shinebourne EA. Evaluation of the effects of isoprenaline and salbutamol aerosols on airways obstruction and pulse rates of children with asthma. Arch Dis Child. 1970;45:766–8. doi: 10.1136/adc.45.244.766.
    1. Silkstone VL, Corlett SA, Chrystyn H. Determination of the relative bioavailability of salbutamol to the lungs and systemic circulation following nebulization. Br J Clin Pharmacol. 2002;54:115–9. doi: 10.1046/j.1365-2125.2002.01632.x.
    1. Beydon N, Davis SD, Lombardi E, et al. American Thoracic Society/European Respiratory Society Working Group on Infant and Young Children Pulmonary Function Testing. An official American Thoracic Society/European Respiratory Society statement: pulmonary function testing in preschool children. Am J Respir Crit Care Med. 2007;175:1304–45. doi: 10.1164/rccm.200605-642ST.
    1. Basu K, Palmer CN, Tavendale R, et al. Adrenergic beta(2)-receptor genotype predisposes to exacerbations in steroid-treated asthmatic patients taking frequent salbuterol or salmeterol. J Allergy Clin Immunol. 2009;124:1188–94. doi: 10.1016/j.jaci.2009.07.043.
    1. Palmer CN, Lipworth BJ, Lee S, Ismail T, Macgregor DF, Mukhopadhyay S. Arginine-16 beta2 adrenoceptor genotype predisposes to exacerbations in young asthmatics taking regular salmeterol. Thorax. 2006;61:940–4. doi: 10.1136/thx.2006.059386.
    1. Beydon N, Pin I, Matran R, et al. Pulmonary function tests in preschool children with asthma. Am J Respir Crit Care Med. 2003;168:640–4. doi: 10.1164/rccm.200303-449OC.

Source: PubMed

3
Subskrybuj