PROJECT SUMMARY – PROJECT 4 For the 5.8 million Americans diagnosed with Alzheimer’s disease and related dementia (ADRD), acute illnesses such as pulmonary embolism (PE) and acute myocardial infarction (AMI) present unique challenges for both diagnosis and treatment. Patients with ADRD bear a disproportionate burden of acute disease, with higher disease risk and lower rates of testing and treatment. At each step of the care pathway, testing and treatment decisions for patients with ADRD are complicated by differences in clinical presentation, communication, and uncertainty about potential recovery from high-intensity care. If patients with ADRD have more difficulty communicating their history and symptoms, or if they present with different sets of symptoms and risk factors, clinicians may have greater difficulty discerning patient risk. Concern about patient recovery from high-intensity care, provider biases, and patients’ differing goals of care may also contribute to low rates of testing and treatment. In this project we will investigate how a claims-based diagnosis of ADRD affects the rate and targeting of diagnostic tests, as well as the benefits and risks of more intensive testing and treatment. Aim 1: Investigate how testing decisions for PE and AMI depend on the presence of diagnosed ADRD and severity of cognitive impairment. Aim 2: Develop and validate a hospital-level measure of PE and AMI testing intensity and diagnostic processes for patients with and without ADRD. Aim 3: Using instrumental variables, test whether hospitals with more intensive testing for PE and AMI among high-risk patients with ADRD achieve better or worse health outcomes for these patients. In addition to collaborating with Core B and C, we will work with Project 1 to contextualize how access to home and community-based services affect nursing home use and recovery from acute illness. In partnership with Project 3, we will test how regional primary care quality predicts care utilization and health outcomes after PE or AMI. In this study, we will examine how more or less aggressive testing and treatment strategies are associated with patient outcomes, including nursing home use, mortality, delayed diagnosis and adverse health events. These results will inform shared decision-making by providers, patients and caregivers, illuminating the clinical tradeoffs of intensive testing and treatment for PE and AMI.