Aspects in Neuropsychology: Depression and Dementia

A complex association exists between late-life depression, cerebrovascular disease, and poor cognitive outcome, including progressive dementia and especially Alzheimer’ s disease. While neuroimaging evidence suggests that cerebrovascular disease plays a prominent role in causing dementia, it appears that depression may also confer substantial risk for developing dementia.

The relationships between the cerebrovascular changes, other struc­tural abnormalities in the brain, specific forms of cognitive dysfunction, and increased risk for developing dementia among those with late-life depression have been difficult to reconcile. Various findings suggest the existence of multiple pathways to poor cognitive outcomes. In this post, we present a framework outlining multiple etiologic and pathogenetic links between depression, cognitive impairment and progressive cognitive decline, including dementia. The suggested framework can assist research by synthesizing the knowledge obtained so far on the depression-dementia relationship, underlying the neurobiological mechanisms which contrib­ute to the identification of at-risk individuals and monitor the impact of depression on the clinical status and course of both illnesses.