Cost‐effectiveness of asthma control: an economic appraisal of the GOAL study

Abstract

Background: The Gaining Optimal Asthma ControL (GOAL) study has shown the superiority of a combination of salmeterol/fluticasone propionate (SFC) compared with fluticasone propionate alone (FP) in terms of improving guideline defined asthma control. Methods: Clinical and economic data were taken from the GOAL study, supplemented with data on health related quality of life, in order to estimate the cost per quality adjusted life year (QALY) results for each of three strata (previously corticosteroid‐free, low‐ and moderate‐dose corticosteroid users). A series of statistical models of trial outcomes was used to construct cost effectiveness estimates across the strata of the multinational GOAL study including adjustment to the UK experience. Uncertainty was handled using the non‐parametric bootstrap. Cost‐effectiveness was compared with other treatments for chronic conditions. Result: Salmeterol/fluticasone propionate improved the proportion of patients achieving totally and well‐controlled weeks resulting in a similar QALY gain across the three strata of GOAL. Additional costs of treatment were greatest in stratum 1 and least in stratum 3, with some of the costs offset by reduced health care resource use. Cost‐effectiveness by stratum was £7600 (95% CI: £4800–10 700) per QALY gained for stratum 3; £11 000 (£8600–14 600) per QALY gained for stratum 2; and £13 700 (£11 000–18 300) per QALY gained for stratum 1. Conclusion: The GOAL study previously demonstrated the improvement in total control associated with the use of SFC compared with FP alone. This study suggests that this improvement in control is associated with cost‐per‐QALY figures that compare favourably with other uses of scarce health care resources.

Health economics of asthma: assessing the value of asthma interventions

“…Seven studies compared combination vs combination (37,43,48,50,52,54,59). Seven additional studies compared combination vs monotherapy (36,40,44,49,53,55,61). Eight studies compared monotherapy vs monotherapy (38,41,42,45,46,51,56,58).…”

“…Clinical treatment guidelines such as GINA and recent trial based cost-effectiveness models like the Briggs et al CEA of the Gaining Optimal Asthma Control (GOAL) study (61) have shifted away from an emphasis on lung function or SFD and moved towards a focus on achieving or maintaining control. These reasons along with the lack of quality for primary outcome measures used in the reviewed studies (22.5% of studies had appropriate outcome measures per QHES item 10), supports the need to develop new asthma simulation models that include comprehensive measures like asthma control in the structure (e.g.…”

Conducting Economic Evaluations Alongside Randomised Trials: Current Methodological Issues and Novel Approaches

“…Results allow a utility (decrement) to be attached to clinical events, and provide a coefficient (mediated by clinical events) which captures utility differences by trial arm. Briggs et al [41] demonstrated that for an RCT where no significant difference in utility was observed using a traditional approach, event-based methods resulted in a moderately significant difference between treatment groups. This approach is more closely aligned with model-based economic evaluations, where utilities are typically attached to health states.…”

Control and severity: complementary approaches to asthma management

“…But these considerations are largely hypothetic and need to be confronted to results of formal cost-effectiveness studies. In the economic analysis of the GOAL study, increasing the proportion of total asthma control was associated with significant gains in quality-adjusted life years, but the corresponding increase in treatment costs was not fully compensated by the reduction in healthcare utilization (23). Another way of determining which level of control has to be achieved is to assess the relationship between control and quality of life; both types of indices usually correlate well with each other (24,25).…”