Blood Biomarkers from Internal Jugular Vein for the Diagnosis of Alzheimer's Disease

The goal of this observational study is to explore the diagnostic performance of blood biomarkers from the internal jugular vein for the diagnosis of Alzheimer's disease (AD) in patients with cognitive symptoms or concerns. The main question it aims to answer is: Whether blood biomarkers from the internal jugular vein outperform those from the median cubital vein which is the routine site for venous blood collection?