Vascular cognitive impairment: dementia biology and translational animal models.

Relationships between cardiovascular risk and disease, and dementia have been identified, and the term vascular cognitive impairment (VCI) is used to describe individuals with significant cognitive impairments produced by cerebrovascular disease (CVD). VCI is the second most prevalent form of dementia and is composed of a heterogeneous pathology. Risk factors for VCI are similar to those of the most prevalent form of dementia, Alzheimer's disease (AD). In addition, recent data suggest that VCI can contribute significantly to the progression of AD, and AD can contribute to VCI. Translational animal models of VCI are necessary to further understand CVD mechanisms contributing to impaired cognition. This review describes animal models of cerebrovascular insufficiency (ie, chronic hypoperfusion and hypertension) that produce experimental VCI, including their relationships to human VCI and, when appropriate, to AD. The use of these models is expected to help discover biomarkers and disease mechanism-linked targets for diagnostic and therapeutic purposes, thus facilitating early identification and intervention in VCI.