The digital revolution in asthma care: unlocking the potential of smart inhalers

Nearly half of all patients with asthma are suboptimally controlled, leading to significant clinical and economic burden. Contributing factors include over- and underdiagnosis, medication non-adherence and poor inhaler technique. This thesis explored the potential of digital inhalers in asthma management. First, the quality and clinical usefulness of spirometry in primary care were evaluated. Although pulmonologists and general practitioners rated over 87% of spirometry tests as clinically useful, only 13% met ATS/ERS quality criteria. Second, a review of medication adherence-enhancing interventions for adults with asthma or COPD informed the design of a practical toolkit to assist healthcare professionals in personalising adherence management, by matching interventions to patient needs. Third, the cluster randomised controlled ACCEPTANCE trial assessed the effects of digital inhalers on medication adherence and asthma control, demonstrating that digital inhalers improve asthma control and short-term adherence, though long-term adherence benefits were limited. Fourth, stakeholder perspectives on implementing digital inhalers into the Dutch healthcare system identified key issues for large-scale implementation and adoption, including the need for evidence of effectiveness, usability issues, workflow changes in healthcare organisations, compatibility issues, the need for reimbursement agreements and data access and security concerns. Finally, this thesis demonstrated the long-term cost-effectiveness of digital inhalers for patients with difficult-to-treat asthma, with projected cost savings of between €3,207 (1-year time horizon and intervention duration) and €26,309 (10-year time horizon and intervention duration) per patient. These savings were mainly driven by fewer patients requiring add-on biologic therapy due to optimised medication adherence and inhaler technique.