Differential degeneration of the locus coeruleus in dementia subtypes.

OBJECTIVE: Neuronal loss in the locus coeruleus (LC) is common in Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). The aims of the present study were to investigate LC degeneration in different dementia disorders including vascular dementia (VaD) and frontotemporal lobar degeneration (FTLD), to compare LC degeneration with severity of pathology in AD and DLB/PDD, to further evaluate the usefulness of a previously presented scoring system and to examine the predictive value of macroscopic assessment of the LC. METHODS: A horizontal mid-level section of the pons was examined in 200 neuropathologically examined cases with clinical dementia. A previous macroscopic assessment of the LC was performed in 149 of the cases. RESULTS: Cases with DLB/ PDD and AD presented with the highest microscopic LC degeneration scores, with significant differences compared to combined AD + VaD, in turn with a higher score than VaD, FTLD and other dementia disorders. Interrater agreement (weighted kappa;) for LC degeneration scoring was 0.83 - 0.91. DLB/ PDD, AD and AD + VaD were the diagnoses for 85% of the cases with macroscopic LC depigmentation. CONCLUSION: LC degeneration, which may be macroscopically noted, often indicates synuclein and/or Alzheimer pathology among demented. When clinical information is scarce or inconsistent, a macroscopic assessment of the LC may facilitate focusing of the subsequent neuropathological investigation. Also, the semiquantitative scoring system is a reliable tool for histological assessment of LC degeneration.

Comparison of four neuropathological scales for Alzheimer's disease.

OBJECTIVE: There are several neuropathological scales for staging of Alzheimer pathology. The system proposed by Braak and Braak is based on the topographic distribution of neurofibrillary tangles and neuropil threads, while that of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) is based on the quantity of neocortical neuritic plaques. A combination of the Braak and CERAD staging scales was recommended by the National Institute on Aging and Reagan Institute (NIA-RI). The Poly-Pathology Alzheimer's Disease assessment, nine areas (PPAD9) is a staging system based on the extent of neuronal degeneration, microvacuolization, cytoarchitectural disorder and gliosis, in addition to neurofibrillary tangles and neuritic plaques, in nine cerebral regions. The aim of the present study was to critically compare these four neuropathological staging scales. METHODS: We assessed the Alzheimer pathology, using the four scales, in 43 patients with various dementia disorders, with focus on concordance and differences between the staging systems. RESULTS: Comparing the staging systems, the Spearman's rho value for PPAD9 vs. Braak was 0.65, for PPAD9 vs. CERAD 0.72, for PPAD9 vs. NIA-RI 0.67, and for Braak vs. CERAD 0.46. CONCLUSION: The correlation between the neuropathological staging systems was suboptimal, and we conclude that the choice of staging system affects the evaluation of Alzheimer pathology, and hence the final diagnosis.

Cause of death in patients with dementia disorders.

BACKGROUND: Investigations on cause of death may provide valuable information about life expectancy and on conditions of terminal dementia care, which perhaps can be ameliorated. METHODS: The autopsy reports were studied on all patients (n = 524; 55.3% females; median age 80 years) with a clinically and neuropathologically diagnosed dementia disorder who underwent a complete autopsy at the University Hospital in Lund, Sweden, during 1974-2004. RESULTS: The two most common causes of death were bronchopneumonia (38.4%) and ischaemic heart disease (23.1%), whilst neoplastic diseases were uncommon (3.8%). In a general population of elderly studied for comparison, bronchopneumonia accounted for 2.8%, ischaemic heart disease for 22.0%, and neoplasm for 21.3% of the deaths. Amongst the demented patients, circulatory and respiratory system diseases were the causes of death in 23.2% and 55.5% of the Alzheimer patients, respectively, whilst the corresponding figures were 54.8% and 33.1% for the patients with vascular dementia. CONCLUSIONS: In patients with dementia, pneumonia as the immediate cause of death may reflect a terminal stage in which patient care and feeding is difficult to manage well. Knowledge about what actually causes death is of value in the terminal care of patients with dementia disorders.