Abstract
INTRODUCTION: Anti-amyloid-β (Aβ) therapies are reshaping Alzheimer's disease (AD) management. Understanding changes in real-world patterns of diagnostic testing and infusion chair usage is essential for optimizing access to care. METHODS: Retrospective analysis of Mayo Clinic enterprise electronic health records (Jan 2019-Mar 2025) assessed trends in AD-relevant brain imaging, fluid biomarkers, apolipoprotein E (APOE) testing, and lecanemab infusions. Rates of amyloid-beta (Aβ) positivity by sex and age, APOE genotype frequencies, and lecanemab treatment initiation and discontinuation were evaluated. RESULTS: Following national insurance coverage changes, lecanemab infusions grew by 110 infusions per quarter to 605 in Q1 2025. Aβ positron emission tomography scans increased (+22/quarter), cerebrospinal fluid biomarker orders declined (-25/quarter), and plasma p-tau(217) orders rapidly increased (+238/quarter). Females were more likely to be Aβ positive (p < 0.006). APOE-ε4 homozygotes were less likely to initiate lecanemab (HR = 0.11, p < 0.001). DISCUSSION: The adoption of anti-Aβ therapies coincided with a rapid shift in diagnostic workflows.