Cerebrospinal fluid markers of pathogenetic processes in vascular dementia, with special reference to the subcortical subtype.

There is a need for improvement of the diagnosis of vascular dementia (VaD). Today, the clinician has to rely on clinical examination, history, and, possibly, brain imaging to identify cerebrovascular damage and other signs of VaD. The clinical diagnosis of subcortical VaD may be difficult because the clinical manifestation of this disorder is often similar to that of Alzheimer disease. There are also mixed forms of the two disorders. Biochemical diagnostic markers, which reflect the pathogenetic processes in the brain, would add to the accuracy of the diagnosis. There are some interesting candidate markers: the cerebrospinal fluid (CSF)/serum albumin ratio could be used to identify blood-brain barrier damage to the small intracerebral vessels, CSF sulfatide to identify ongoing demyelination of the white matter, CSF neuron-specific enolase to identify ongoing neuronal degeneration, and CSF tau protein and CSF neurofilament light protein to identify ongoing axonal degeneration. None of these potential markers is specific to subcortical VaD, but together and used in conjunction with the conventional diagnostic workup, they may be of diagnostic value.