Vascular Cognitive Impairment and Dementia

Tables 2 and 3 summarize two sets of diagnostic criteria for vascular dementia, the California (Chui et al. 1992) and NINDS-AIREN (Roman et al. 1993) criteria. These criteria are similar, in that they require evidence of strokes, both clinically and by imaging studies (and not just white mat­ter changes on MRI), and also evidence of cognitive impairment. Both make clear that definite vascular dementia can be diagnosed only with neuropathology, usually an autopsy study, so that the most a clinician can diagnose is “probable” or “presumed” vascular dementia. Both sets of criteria include either supporting and contravening factors, in the case of the California criteria (e.g., aphasia without an infarct on MRI in the language area would favor Alzheimer’s disease) or “typical features” in the NINDS-AIREN criteria; both listings contain clinically useful items. There are some important differences. The California criteria utilize only ischemic strokes, whereas the NINDS-AIREN criteria allow both infarc­tions and hemorrhages. The California criteria also include more explicit rules for imaging evidence of strokes, and they require progressive cogni­tive dysfunction, whereas the NINDS-AIREN criteria specify only that the dementia and cerebrovascular disease must be “reasonably related,” usu­ally meaning onset of cognitive problems within 3 months of a stroke.

Table 1

Hackinski Ischemic Score

Evidence of associated atherosclerosis

Source: Hachinski et al. 1975

Note: Patients with a total score of > 7 are considered to have multi-infarct dementia; those scoring < 4 have primary degenerative dementia.

The following factors support the diagnosis of IVD: history of TIA’s, hypertension, or other risk factors for cerebrovascular disease; early gait disorder; extensive deep white matter disease; focal abnormalities on PET or SPECT functional brain imaging. Against ischemic vascular dementia were: absence of focal neurological signs other than cognitive abnormali­ties; and presence of aphasia, apraxia, or agnosia without appropriate lesions on CT or MRI scans.

Source: Chui et al. 1992.

The diagnosis of vascular dementia, by these criteria, also must include a decline in memory and at least two other domains of intellectual ability, with resultant impairment of activities of daily living. Single strokes are permitted, if the other criteria apply. The NINDS-AIREN criteria also emphasize typical clinical features of impairment of multiple cognitive domains, usual presence of focal neurological signs, gait abnormalities, mood changes, psychomotor slowing, and extrapyramidal signs. Against vascular dementia were early onset and progres­sive worsening of a deficit in memory or other cognitive functions, in the absence of focal lesions on CT or MRI scans; absence of focal neurological signs, other than cognitive ones; and absence of infarcts on brain imaging studies.

Source: Roman et al. 1993.

The diagnosis of vascular dementia, by these criteria, also must include a decline in memory and at least two other domains of intellectual abil­ity, with resultant impairment of activities of daily living. Single strokes are permitted if the other criteria apply. The NINDS-AIREN criteria also emphasize typical clinical features of impairment of multiple cognitive domains, usual presence of focal neurological signs, gait abnormalities, mood changes, psychomotor slowing, and extrapyramidal signs. Against vascular dementia were early onset and progressive worsening of a deficit in memory or other cognitive functions, in the absence of focal lesions on CT or MRI scans; absence of focal neurological signs, other than cognitive ones; and absence of infarcts on brain imaging studies.