Understanding Ambulatory Care Utilization in Alzheimer's Disease and Related Dementias (ACUA) - Dementia is a disease characterized by a loss of memory and other cognitive functions that is severe enough to interfere with daily living. In 2023, an estimated 6.7 million Americans who are 65 years and older are living with dementia (Alzheimer's disease or related dementias, ADRD). Approximately one-third of people living with dementia (PLWD) have highly “fragmented ambulatory care,” or care diffusely spread across many ambulatory providers. In one national study, PLWD who had highly fragmented ambulatory care had an average of 16 ambulatory visits to 7 different providers in a given year, compared with 11 visits to 3 providers for those with the least fragmented care. Having multiple providers may be clinically appropriate, but it creates challenges, because providers do not consistently communicate with each other, even in the era of electronic health records. When providers do not communicate with each other, harm for patients can follow. Fragmented ambulatory care may be an overlooked but modifiable contributor to some key problems in healthcare delivery, such as delayed or missed diagnoses of dementia (including racial disparities in dementia diagnoses). Similarly, fragmented care may be leading to more prescribers of medication and more polypharmacy (i.e., the use of ≥5 medications), which may be contributing to excess emergency department visits and hospitalizations among PLWD. Filling these gaps in knowledge is necessary for informing the design of future interventions. The proposed project, “Understanding Ambulatory Care Utilization in Alzheimer's Disease and Related Dementias (ACUA),” will illuminate the role of fragmented care in the diagnosis of dementia and in the care of PLWD, while identifying novel opportunities for intervention. Aim 1 will involve secondary analyses of two NIA- funded cohort studies linked to claims (the Health and Retirement Study [N ≈ 3,425] and the REasons for Geographic and Racial Disparities in Stroke study [N ≈ 3,235]), to determine whether fragmentation is associated with delayed or missed diagnoses of dementia, including racial disparities in diagnoses. Aim 2 will involve secondary analyses of national Medicare claims (100% sample) to determine whether fragmentation is associated with more unique prescribers of medication and whether that, in turn, leads to more polypharmacy and excess emergency department visits and hospitalizations (N ≈ 4.5 million). Aim 3 will consist of one-on- one semi-structured interviews with a variety of stakeholders who are involved in dementia care, to determine their preferences regarding who should address fragmented care for PLWD, when, and how (for example, whether the goal of future interventions should be to decrease unnecessary fragmentation or to ameliorate its adverse effects) (N ≈ 50). This project will generate robust, data-driven insights, which will enable future development of novel interventions to improve ambulatory care and outcomes for PLWD.