Progressive morphometric and cognitive changes in vascular dementia.

Evidence for progressive cognitive decline in vascular dementia (VaD) is mixed, with some studies showing little or no decline over time. One possible explanation for these inconsistent findings is the heterogeneity of pathology encompassed by the VaD diagnosis. It is possible that subtypes of VaD (i.e. those resulting from different lesion distributions) show different patterns of cognitive decline. In the present study, a heterogeneous VaD group demonstrated cognitive decline from baseline to 12-month follow-up. Although this decline was coincident to morphometric changes (i.e. increased subcortical hyperintensities (SH), decreased whole brain volume (WBV)), no relationship emerged between cognitive decline and morphometric changes. Preliminary examination of VaD subtypes revealed patients with subcortical infarct or SH-only exhibited greater decline than VaD patients with cortical lesions. Further research is needed to determine whether this observed decline is attributable to differential lesion distribution or statistical artifact.