Age –related cerebral degenerative changes are coupled therefore with decreased perfusion, usually
assumed to be secondary to decreased cerebral metabolic demands (Meyer et al., 1999). During ageing
declines in cerebral tissue densities in gray (polio-araiosis) and white matter (leuko-araiosis) reflect
neuronal degenerative changes, which progress concurrent with cerebral perfusion declines. Rates of
polio- and leuko-araiosis accelerate geometrically after age 60, correlating with cortical and
subcortical atrophy and ventricular enlargement.
In particular, leuko-araiosis correlates with advancing age, cerebral atrophy, hypoperfusion of white
matter, and cognitive impairments (Meyer et al., 2000): what is surprising, is that leuko-araiosis is
detectable in 9-19% of older “normal” subjects but is virtually always present in vascular dementia.
Of special interest are the data emerging from the study of Meyer et al. (2000): normative subjects
destined for later cognitive decline had excessive leuko-araiosis at study entry, suggesting leukoaraiosis
is, itself, a risk factor for cognitive decline.We have studied the emerging role of hypotension in SVAD definition
