Dry-powder inhaler use in primary school-aged children with asthma: a systematic review.

Objective: Asthma is the most common chronic disease among children. Dry-powder inhalers (DPIs) are effective for medication delivery in adults and adolescents, and provide a lower environmental footprint and more portability than a metered dose inhaler (MDI) with a spacer. They require a specific technique, and it is necessary to ascertain whether they can be used in younger age groups. We aimed to assess evidence regarding whether primary school-aged (5-11 years) children can use DPIs with adequate technique during both stable and acute asthma. Design: Ovid MEDLINE, Embase and PubMed were searched for studies assessing DPI use among children aged 5-11 years with asthma or wheeze. Results of studies were synthesised by study design and outcome measure. Results: 38 studies were identified for analysis. These were analysed in three groups: 1) 25 studies assessing children's ability to use DPIs by peak inspiratory flow measurement, 2) 10 studies assessing children's ability to use DPIs by physician assessment, and 3) three studies measuring the efficacy of DPIs compared with the gold standard (MDI with spacer). Five studies included children during acute exacerbations. Conclusion: The majority of primary school-aged children have the ability to use a DPI with adequate training, support and practice. Some younger children may have difficulties, and clinician assessment and ongoing review is crucial in determining which children are likely to benefit from a DPI. Consistent correct use and adherence remain as challenges, but these are also issues with an MDI plus spacer and do not appear to be significantly worse with DPIs. Evidence of the use of DPIs during acute illness is limited; more studies are required in this setting.