Vascular pathology as a Key Factor for Overall Cognitive Impairment Lead Investigator: Vladamir Hachinski Institution : London Health Sciences Centre, Western Ontario U. E-Mail : lsposato@uwo.ca Proposal ID : 348 Proposal Description: Abstract: ???Alzheimer???s disease??? and ???vascular dementia??? are thought to be the most common causes of dementia. However, on the basis of current evidence, classifying dementias into vascular, mixed and degenerative disorders has not led to significant improvements in the treatment of patients with cognitive impairment. Mainly, the incorrect diagnoses and lack of adequate pathophysiological characterization of dementing disorders likely results in missed opportunities for identifying treatable and preventable causes, such as vascular disease. Thus, recognizing the vascular component of dementias is imperative from a prevention standpoint. Our project aims to assess the role of the vascular component in the pathophysiology of overall cognitive impairment by means of answering 4 questions: (1) What is the threshold of vascular lesions or vascular markers sufficient enough to produce dementia? (2) To what degree can vascular lesions explain cognitive impairment in patients with AD pathology? (3) Does executive dysfunction predict the long-term risk of a higher burden of vascular lesions? (4) What proportion of overall cognitive impairment is attributable to vascular pathology?