A regional registry ensures clinical guideline adherence and economic sustainability of Alzheimer’s disease treatment: a 12-year population-based study in Catalonia

Population-based registries for Alzheimer's disease pharmacological treatment are essential tools for monitoring clinical guideline adherence and health system sustainability. This retrospective observational study analyzes 12 years of real-world data from the Catalan Registry of Pharmacological Treatment of Alzheimer's Disease (RTFMA) between 2012 and 2024. Analyzing a cohort of over 158,000 patients treated with acetylcholinesterase inhibitors or memantine, we found that the treated population increased by 24.5%, reaching 56,874 individuals in 2024. The implementation of a mandatory registration system was associated with high clinical appropriateness, with 81.9% of treatments initiated at recommended moderate stages (GDS 4-5), while only 8.6% began at mild stages. Despite the aging population and the impact of the COVID-19 pandemic-which caused a transient decline in treatment initiations in 2020-the system demonstrated resilience with a full recovery by 2023. Treatment discontinuation was primarily driven by mortality (95% of known reasons), indicating high persistence until end-of-life. From an economic perspective, Alzheimer's therapies represented a stable 1.9% of the total public pharmaceutical budget in 2023, reflecting effective cost containment through generic drug use. These findings suggest that a centralized, guideline-linked registry optimizes patient selection and maintains the economic viability of Alzheimer's care, providing a robust framework for the future integration of high-cost disease-modifying therapies.