Objectives Around 10–15% of children do not achieve adequate asthma control when using low-dose inhaled corticosteroids (ICS). When asthma exacerbations occur, treatment involves add-on preventer therapies, although there is uncertainty concerning their clinical and cost-effectiveness. We previously determined that treatment escalation beyond low-dose ICS in children/adolescents with uncontrolled asthma may not be cost-effective based on an assessment of their costs per quality-adjusted life year (QALY).1 We aim here to estimate the cost-effectiveness of treatments based on alternative measures of health outcome.

Methods A Markov state-transition model was developed to simulate 1-year National Health Service costs and health outcomes associated with low, medium and high dose ICS, ICS in combination with long-acting β2-adrenoceptor agonists (LABAs) or leukotriene receptor antagonists (LTRAs). Health states were defined based on asthma control, exacerbation and death. Resource use comprising of primary and secondary care services were identified from literature searches, and unit costs for 2020/21 were derived from standard sources. Transition probabilities pertaining to low-dose ICS were adjusted by relative risks for asthma control and exacerbations for each treatment, derived from a network meta-analysis.2 Total costs, days of controlled asthma and exacerbation-free days were computed, and incremental cost- effectiveness ratios (ICERs) estimated.

Results High-dose ICS was associated with the highest cost (£495), and LTRA the lowest (£101). Medium-dose ICS + LABA provided the most benefit in terms of days of controlled asthma (336), and LTRA the least (294). High-dose ICS, medium-dose ICS + LABA and low-dose ICS were each associated with 362 exacerbation-free days. Analysed incrementally, low-dose ICS was associated 39.7 additional days per year of controlled asthma compared with LTRA and an ICER of £1.24; while medium-dose ICS + LABA provided a further 1.0 day of controlled asthma at an incremental cost of £141.30. The other treatments were either dominated or extendedly dominated. The incremental cost per exacerbation-free day was least for low-dose ICS at £4.56 versus LTRA, followed by medium-dose ICS + LABA (£351.01) and high-dose ICS (£495.74).

Conclusion In contrast to QALYs, where an explicit threshold range has been defined for healthcare decisions (£20,000–£30,000 per QALY gained for most health technologies in the UK), there are no value thresholds for outcomes specific to asthma. Nonetheless, the magnitude of the ICERs support the cost-utility analysis in suggesting that, at current prices, low-dose ICS may be cost-effective for the avoidance of exacerbations and for achieving asthma control.