Abstract
This thesis aimed at investigating whether the regulation of cerebral perfusion is impaired in patients with Alzheimer’s disease and whether this regulation is altered by treatment with cholinesterase inhibitors. This aim has first been translated in two literature studies on the clinical and methodological background of this hypothesis, and in two studies on methodologies to investigate the regulation of cerebral blood flow in older persons. Subsequently, we have applied our measurements on the regulation of cerebral blood flow during blood pressure changes in patients with Alzheimer’s disease and we have compared the results to those of healthy older subjects. Finally, the effects of cholinesterase inhibitors on the systemic circulation and on the regulation of cerebral cortical oxygenation were assessed in Alzheimer patients.
The main findings of these studies are the following: first, in patients with Alzheimer’s disease, the regulation of cerebral perfusion during fast blood pressure changes is not affected at the level of the major supplying artery of the brain. However, the function of the cerebral microcirculation to maintain brain tissue oxygenation during fast blood pressure changes, is comprised. Second, treatment with cholinesterase inhibitors in patients with Alzheimer’s disease does not provoke initial orthostatic hypotension and does not impair static cerebral autoregulation. And third, this treatment seems to stimulate cerebral metabolism and oxygen use in patients with Alzheimer’s disease.
