4 Evidence

4 Evidence

4.1 Delivery of corticosteriods by a hand held device
The evidence base for pressurised metered dose inhalers (pMDIs) plus spacer versus dry-powder inhalation systems (DPI) for the delivery of corticosteriods in children with chronic asthma is relatively small and of poor quality. Two randomised controlled trials were identified, which recruited children of 5 years or under. These trials involved a total of 140 children, although the majority of these recruited children of 5 years or older. One of these trials was inadequately powered and compared a pMDI alone (not recommended by current BTS guidelines) versus DPI. The second and largest trial demonstrated no difference in steroid delivery via a pMDI plus spacer compared to DPI (at half MDI dosage).

4.2 Delivery of ß 2 agonists by a hand held device
The evidence base for pressurised metered dose inhalers (pMDIs) alone or pMDI plus spacer compared to dry-powder inhalation systems (DPI) in children with chronic asthma is poor. Four randomised controlled trials were identified that recruited children of 5 years or less. These trials involved a total of 278 children, some of which were aged 5 years or more. The remaining three studies demonstrated no difference when comparing ß2 agonist delivery via pMDI plus spacer with ß2 agonist delivery by DPI.

4.3 Delivery of ß 2 agonists or anticholinergics by nebuliser
The evidence for nebulised bronchodilators compared with bronchodilator delivery via hand held device in children with chronic asthma is also poor. Three randomised controlled trials which recruited children aged 5 years or less, were identified. These trials were small and involved a total of 51 children, although many of the children were aged 5 years or older. No differences were found between nebulisation, pMDIs or dry powder devices. These trials are likely to be of insufficient size to detect small differences between devices.

4.4 Cost Effectiveness
There is currently a wide range in the cost of drug/inhaler combinations. No cost effectiveness studies were identified that make direct comparison between asthma devices in children under the age of 5 years with chronic asthma.

4.5 The documentation and opinion available to the Appraisal Committee is set out in Appendix B.