Blood And Tears in Alzheimer's Disease

Participants under investigation of a neurodegenerative disease who have a planned lumbar puncture in the Memory clinic will be invited to this study. On the same day of the lumbar puncture, tear fluid and dry blod spots will be collected. Tear fluid is collected using Shirmer's test. Dried blood spots are obtained by a small prick in the finger with a lancet. The blood droplet is transferred onto a special piece of filter paper, where it dries. As a sub-study, participants who have provided written consent specifically for this purpose will repeat the test with dried blood spots at home one week after participating in the study. The samples are submitted to the Memory Clinic at the participant's next scheduled appointment. Tear fluid, dried blood spots, as well as blood and cerebrospinal fluid will be examined for AD-related pathology.