OBJECTIVES: Clinical trials found lecanemab (Leqembi) effectively slowed cognitive decline in early-stage Alzheimer’s Disease. However, carriers of the APOE ε4 gene experienced higher incidence of brain swelling and/or hemorrhage. Testing for APOE ε4 may be a leading indicator of intent to seek treatment with lecanemab. We describe the trends in APOE genetic testing.

METHODS: Using a subset of US real-world EHR data from Truveta, we identified patients with Alzheimer’s or dementia (henceforth referred to as the overall population) and those who received an APOE test, from January 2016 - April 2023. We provide descriptions of demographic and SDOH factors for overall and APOE populations and compare the number of tests in the first four months of 2021, 2022, and 2023.

RESULTS: We identified 636,667 people matching the inclusion criteria, of which 370 people received APOE genetic testing. Both populations are primarily female (overall: 59.2%, APOE: 62.7%), white (overall: 80.4%, APOE: 84.9%), and non-Hispanic or Latino (overall: 90.8%, APOE: 87.3%). A higher percentage of the overall group is over 85 years of age (overall: 33.9% compared to 14.3%). For individuals with available SDOH data, the APOE group has higher rates of owning their place of living (82.6% compared to 75.0%) and have household incomes above $100,000 (22.6% compared to 4.4%) than the overall group. The count of tests in January–April 2023 is 1.6x and 2.3x higher than in January–April 2022 and 2021, respectively.

CONCLUSIONS: The increased APOE genetic testing amongst people with Alzheimer’s or dementia may show an early indication to seek treatment with lecanemab. The population receiving testing was younger and of higher SES status compared to the overall population. More research is needed to determine the results of these tests and whether they impact lecanemab prescription. We will continue to monitor testing increases, lecanemab usage, and potential adverse events.