Home Test for Measuring Plasma P-tau217 in Alzheimer's Disease

Inclusion Criteria: * Subject with Alzheimer's Disease Only: diagnosed according the NIA-AA diagnostic AD criteria * Healthy Control Only: Subject does not have history of cognitive impairment * 55 - 90 years old * Subject able to comply with study procedures * Subjects must be able to use the Tasso device for blood sample collection as per the provided instructions (can be performed with the assistance of a caregiver) * Subjects must be able to undergo IV sampling * Have a study partner who will provide written informed consent to participate, and assist with blood collection when applicable Exclusion Criteria: * Subjects with systemic conditions which were not adequately controlled through a stable medication regimen * Subjects with any known significant bleeding disorders or conditions that contraindicate blood sample collection (e.g., hemophilia, severe thrombocytopenia) * Subjects with a known history of severe skin allergies or reactions to adhesives (since the Tasso device involves adhesive application to the skin) * Subjects currently taking anticoagulant or antiplatelet medications that could interfere with blood collection or increase the risk of complications * Subjects who have undergone major surgery or have been hospitalized for any reason in the last 3 months prior to study enrollment * Participation in a clinical study within the 2 month