Biochemistry of Middle and Late Life Dementias

Abstract

The disease entities to be considered in this review are characterized clinically by a slow but relentless deterioration of intellectual faculties resulting in profound dementia and eventually death during middle and late life. Alzheimer’s disease, Pick’s disease, Huntington’s chorea, Creutzfeldt-Jakob disease, and senile dementia are included in this group of “primary dementias” where the unifying pathologic feature is a degeneration of the cerebral cortex with varying degrees of involvement of related structures. These conditions, which as yet have no established cause (the special status of Creutzfeldt-Jakob disease is discussed below) and as far as can be determined at present are not related to any known disorder, stand in contrast to the “secondary dementias” that occur in association with syphilitic infection, cerebrovascular disease, brain tumor, myxedema, alcoholism, nutritional deficiencies, encephalitis, trauma, and chronic neurological diseases such as disseminated sclerosis, subacute combined degeneration, Wilson’s disease, and the cerebral lipidoses. These secondary dementias are considered elsewhere in this Handbook.