Hemodynamic disturbances and dementia: On the crossroads between vascular brain injury and Alzheimer’s disease pathology

Abstract

Dementia is a common problem among older adults. Due to aging of the population, the number of people with dementia is expected to further increase in the coming decades. It is therefore important to have effective prevention and treatment strategies. Currently, these are unavailable, because – among other reasons – the disease processes that underly dementia are not fully understood. An additional complicating factor is that there are different types of dementia, such as Alzheimer’s disease and vascular dementia. These two types of dementia are characterized by different, specific brain injury and consequently also by specific symptoms. However, Alzheimer’s disease and vascular dementia can coincide within the same person. This thesis therefore examined whether an impaired cerebral blood flow could be a common underlying mechanism for Alzheimer’s disease and vascular dementia. Cerebral blood flow can be impaired as a consequence of disturbed blood pressure (such as with large variability in blood pressure) or by an obstruction of the blood flow to the brain (caused by an occluded carotid artery). This thesis showed that increased blood pressure variability was associated with brain injury that is related to vascular dementia. Increased blood pressure variability and an occluded carotid artery were not associated with brain injury that is related to Alzheimer’s disease. This means that an impaired cerebral blood flow is not a common underlying mechanism for Alzheimer’s disease and vascular dementia, but it could be a potential target for prevention and treatment of vascular dementia.