[An analysis of the causes of dementia in 383 elderly autopsied cases]

To survey the causes of dementia confirmed by autopsy in the elderly and to have a better understanding of various causes of senile dementia.

A retrospective study on clinical and pathological diagnosis in 383 cases aged 60 and over with autopsy performed was carried out clinical diagnosis of dementia was based on DSM-IVR, NINCDS-ADRDA and NINCDS-AIREN criteria. Gallyas-Braak staining, Tau and Ubiquitin Immunohistochemistry staining were adopted for diagnosing neurodegenerative dementia and distinguishing various degenerative diseases.

Among the 383 aged cases with consecutive autopsy, 78 cases were found to have clinical features and brain pathologic change related to dementia. The incidence of dementia in the aged patients with autopsy was 20.4%. Of all the cases, vascular dementia accounted for 38.5% (30 cases), being the most frequently on countered. Next in order were degenerative dementias including Alzheimer's disease (11 cases) and non-Alzheimer's degenerative dementia (9 cases) including dementia with Lewy bodies, corticobasal degeneration, progressive supranuclear palsy, Pick's disease and idiopathic Parkinson'disease. Degenerative dementias accounted for 25.6% (20 cases). Various medical disorders including hepatic encephalopathy, pulmonary encephalopathy, hypoglycemia with cognitive impairment were also relatively common, they accounted for 20.5% (16 cases). The other less common causes included brain tumor, normal pressure hydrocephalus and subdural hematoma, 12 cases accounted 15.4%. The total accordance rate of clinical and pathologic diagnosis of senile dementia was 64.5%, the accordance rates of medical disorders such as hepatic encephalopathy, pulmonary encephalopathy and brain metastatic tumors were all 100%, the accordance rate of vascular dementia and degenerative dementia was 66.7% and 40% respectively.

Senile dementia is a clinical syndrome caused by multiple factors. Physician should think of various possible causes of dementia, basing on their clinical history and laboratory results. Promoting autopsy and adopting new pathological techniques would increase the diagnostic accuracy of degenerative dementia.