Table 1.

Definitions used for creating patient subgroups based on clinical, MRI and CSF fluid markers.

Diagnoses	Description
Subcortical ischemic vascular disease (SIVD)	SIVD is the small vessel form of VCID. It is diagnosed by a progressive growth of the WMHs. They met both the Erkinjuntti [20] criteria for subcortical vascular dementia and the recent consensus statement for SIVD [21, 22]
Alzheimer’s disease (AD)	Patients diagnosed with AD presented with insidious onset of predominant amnestic disorder associated with one additional cognitive domain, following NINCDS-ADRDA clinical criteria for probable AD [23, 24 ]. In addition, they conformed to the recent biological diagnostic criteria for AD [3], which includes the biomarkers of the AD pathophysiologic process, low CSF Aβ42/Aβ40 and elevated phospho-Tau.
Mixed dementia (MX)	MX is diagnosed by a combination of CSF biomarkers for AD and white matter injury markers of SIVD derived from diffusion tensor imaging [17, 18].
Multiple infarcts (MI)	MI patients have multiple strokes, generally involving large vessels, but it also includes isolated lacunar strokes confined primarily to thalamus or basal ganglia (single strategic strokes) [46]
Leukoaraiosis (LA)	LA is diagnosed by a combination of white matter changes on FLAIR MRI but without the evidence of dementia and minimal or no cognitive changes on neuropsychological testing. This use of the term follows the original intent of Hachinski [25] and has no connotations of pathological implications.