[The effect of rivastigmine on cognitive functions and regional cerebral blood flow in Alzheimer's disease and vascular dementia: follow-up for 2 years].

Background And Purpose: The aim of the work was to investigate the effect of treatment with rivastigmine, one of the inhibitors of acetylcholinesterase (AChE-I) on the regional cerebral perfusion (rCBF) and the cognitive functions of the brain in patients with Alzheimer's Disease (AD) and Vascular Dementia (VaD).

Material And Methods: The investigations of rCBF were carried out using SPECT (Single Photon Emission Computed Tomography). The results given concern investigations of patients carried out at the onset of the investigation, after 12 months, and 24 months of rivastigmine treatment.

Results: In patients with AD it was found that treatment with rivastigmine increases rCBF by 5-7% in the temporal areas during the first 12 months. In the frontal areas the increase was by 3-5%. During the next 12 months rCBF with an accuracy of 2% returned to the initial level, with the exception of the motor cortex, where it remained on the level increased by 5-6%. However, the cognitive functions remained constant during the first 12 months of treatment and decreased significantly during the next 12 months. In patients with VaD rCBF increased in all the regions of the brain except for the temporal posterior regions, and remained at an elevated level for the next 12 months. The cognitive functions deteriorated slowly, but to a much lesser degree than in the case of AD.

Conclusions: From the investigations carried out it follows that treatment with rivastigmine during 24 months prevents a decrease of rCBF in patients with AD. However, the cognitive functions deteriorate after 24 months.