Dementia in hereditary cerebral hemorrhage with amyloidosis-Dutch type is associated with cerebral amyloid angiopathy but is independent of plaques and neurofibrillary tangles

Cerebral amyloid angiopathy is frequently found in demented and nondemented elderly persons, but its contribution to the causation of dementia is unkn own. Therefore, we investigated the relation between the amount of cerebral amyloid angiopathy and the presence of dementia in 19 patients with heredi tary cerebral hemorrhage with amyloidosis-Dutch type. The advantage of stud ying hereditary cerebral hemorrhage in amyloidosis-Dutch type is that patie nts with this disease consistently have severe cerebral amyloid angiopathy with minimal neurofibrillary pathology. The amount of cerebral amyloid angi opathy, as quantified by computerized morphometry, was strongly associated with the presence of dementia independent of neurofibrillary pathology, pla que density, or age. The number of cortical amyloid beta -laden severely st enotic vessels, vessel-within-vessel configurations, and cerebral amyloid a ngiopathy-associated microvasculopathies was associated with the amount of cerebral amyloid angiopathy and dementia. A semiquantitative score, based o n the number of amyloid beta -laden severely stenotic vessels, completely s eparated demented from nondemented patients. These results suggest that ext ensive (more than 15 amyloid beta -laden severely stenotic vessels in five frontal cortical sections) cerebral amyloid angiopathy alone is sufficient to cause dementia in hereditary cerebral hemorrhage with amyloidosis-Dutch type. This may have implications for clinicopathological correlations in Al zheimer's disease and other dementias with cerebral amyloid angiopathy.