Neuropathological findings and staging in dementia

Dementia is a clinical syndrome with the development of impairment in multiple cognitive functions (including memory), severe enough to interfere with activities of daily living, as the main symptom. There are a large number of disorders that can lead to dementia, and neuropathological examination after death is necessary to determine the underlying cause with certainty. The overall aim of this thesis was to investigate neuropathological findings in patients with dementia and neuropathological staging of dementia disorders, the main potential gain being increased epidemiological knowledge and improved neuropathological dementia diagnostics. We could confirm the generally accepted opinion that on a neuropathological basis, Alzheimer’s disease (AD) is the most common dementia disorder, followed by vascular dementia (VaD) and mixed AD+VaD. Also, in a significant number of patients, the clinical dementia subtype diagnosis does not correspond with the neuropathological findings. Furthermore, degeneration of the nucleus locus coeruleus, often seen already macroscopically, generally indicates the diagnoses Lewy body disease (LBD) or AD among the demented, while a preserved locus coeruleus occurs mainly in VaD and frontotemporal lobar degeneration (FTLD). Moreover, various neuropathological staging systems for AD differ in procedure and targeted pathology, and the choice of system affects the judgement of Alzheimer pathology and hence the final diagnosis. Also, various neuropathological LBD staging systems differ in applicability and to some extent in the judgment of Lewy-related pathology.