Inhaler devices for routine treatment of chronic asthma in older children (aged 5–15 years)

Overall budget impact is very sensitive to device prescribing patterns, since acquisition costs of inhalers delivering the same class of drug at the same dose vary substantially (as outlined in 4.11). However, with the exception of spacer devices, it is difficult to predict the impact of the guidance set out in section 1 on local inhaler prescribing patterns and costs. Consequently, an estimate of current inhaler prescribing patterns in primary care is set out below for England and Wales. These prescribing rates and costs can be used together with local information on inhaler use to calculate the likely local cost impact of the guidance. Estimates of the cost impact of the guidance as regards spacer devices are detailed in 5.5.

Analysis of inhaler device prescribing in a large sample of older children treated in primary care shows that press-and-breathe pMDIs account for 60% of prescribed items, breath-actuated pMDIs account for 17%, and DPIs account for 23%.

Applying the estimates in 5.2 to England and Wales as a whole suggests that the approximate current annual acquisition costs for devices prescribed to children aged 5–15 years in primary care are as follows: £11.2 million (£1499 per 1000 total population aged 5–15 years) for press-and-breathe pMDIs, £4.2 million (£562 per 1000) for breath-actuated pMDIs, and £21.7 million (£2898 per 1000) for DPIs.

In addition, the analysis shows that in primary care, only 20% of children aged 5–15 prescribed a press-and-breathe pMDI delivering corticosteroids are currently prescribed a spacer attachment. The estimated total annual acquisition cost for spacer attachments is currently £233,000 (£31 per 1000) in England and Wales as a whole.

If all children prescribed a press-and-breathe pMDI delivering corticosteroids in primary care were to be prescribed one spacer attachment per year, it is estimated that the total annual acquisition cost in England and Wales would increase to £1.2 million (£156 per 1000). Manufacturers generally recommend two spacers per year.

In addition to any anticipated changes in device acquisition costs, it is also important that planning recognises the wider resource implications of implementing the guidance, including those set out in 1.4 and 7.3.