Biochemical diagnosis of vascular cognitive impairment associated with subcortical small vessels disease

Subcortical small-vessel disease (SSVD) is a disorder that has been fully described in clinical, neuropathological and imaging aspects. It is considered as the most prevalent ischemic CNS disorder and has been associated to arterial hypertension, diabetes mellitus, dyslipidemia and obstructive sleep apnea. The hallmark of SSVD is the ischemic white matter lesions which can be presented as lacunar infracts and global brain hypoperfusion in a common and homogeneous subtype of vascular cognitive impairment (VCI) which is often unrecognized. The special nature and course of SSVD offers the opportunity of collecting knowledge at all stages of its pathogenicity. Arteriosclerosis, hypoxic hypo-perfusion and inflammation act synergistically, causing myelin degeneration and blood brain barrier alteration. Clinical diagnosis of SSVD includes early executive dysfunction manifested by impaired capacity to use complex information, to formulate strategies, and to exercise self-control. Brain imaging has advanced substantially the diagnostic tools for SSVD. Diagnostic biomarkers for Alzheimer Disease include reduction of cerebrospinal fluid amyloid-beta (A beta)42 and of the ratio A beta 42/A beta 40 sometimes with increased total tau levels. However, biomarkers specific for the diagnosis at all stages of SSVD are needed, especially because of the unsatisfactory treatment options at its late stages to date.