OBJECTIVES: To develop a novel economic modeling approach for asthma based on the continuous Asthma Control Questionnaire (ACQ) measure that more fully captures clinical trial data and other treatment factors used in clinical practice.
METHODS: We conducted a targeted review of published cost-effectiveness models and health technology assessments for asthma to identify approaches to modeling asthma control and its association with exacerbation risk and health-related quality of life. To address limitations in published models, we developed a hybrid approach using continuous ACQ score trajectories to represent patients’ day-to-day symptoms and Markov-based health states for exacerbations and death. ACQ score trajectories were defined continuously over time using mean change from baseline. During each 2-week model cycle, exacerbation risks and utility values for the day-to-day symptoms state were dependent on the current mean ACQ score. We populated the model with data from the PrimoTinA-asthma trials comparing triple and dual inhaled therapies and other literature and validated the model outcomes against published models.
RESULTS: The targeted review found that previous models typically utilized Markov-based approaches with discrete asthma control health states that did not capture ACQ improvements within states. Based on the PrimoTinA-asthma ACQ score trajectories (from 2.63 at baseline to 2.01 for triple therapy versus 2.17 for dual therapy at 52 weeks), over a 1-year (5-year) time horizon, our model predicted an average of 0.454 versus 0.558 (2.326 versus 2.875) severe exacerbations and 0.766 versus 0.755 (3.561 versus 3.503) discounted quality-adjusted life-years. Model results were comparable to those reported for published models.
CONCLUSIONS: This novel modeling approach for asthma captures the impact on economic and health outcomes of clinically relevant changes in asthma control and may be used in future economic evaluations in asthma.
