Hypertension, Brain Clearance, and Markers of Neurodegeneration

Over 5 years the investigator will conduct a 24-month longitudinal study of 80 cognitively healthy subjects 60-80 years old, classified at baseline into the following groups: 1) Normotensive NT (n=20), 2) Controlled hypertension C-HTN (n=20), 3) Uncontrolled hypertension or Untreated hypertension UU-HTN (n=30). For subjects in the NT and C-HTN groups this will be an observational longitudinal study with clinical, imaging and CSF (cerebrospinal fluid) assessment at baseline and 24 month follow-up, with 3 visits to monitor BP (blood pressure) in-between (both at the office and using home BP monitoring). Subjects in the UU-HTN group after having completed their baseline evaluation will be referred for a further evaluation of HTN (hypertension) and an intervention. Intervention: the initiation of treatment or treatment modification to achieve the SBP (systolic blood pressure) goal of \<140 mmHg. Subjects will be referred to their physician or, in case they do not have one, to the study cardiologist for treatment according to current guidelines. Imaging at 0 and 24 month consist of MRI (magnetic resonance imaging) with ASL (arterial spin labeling) and brain clearance imaging using 18F-MK6240 PET (positron emission tomography). CSF assessment includes Aβ42 (amyloid beta 42), t-tau (total tau) and p-tau181 (tau phosphorylated at threonine 181).