Vascular Dementia: Pathological Findings. In: Burns A, Levy R, editors. Dementia. Boston: Springer US; 1994. pp. 653-63. [DOI: 10.1007/978-1-4615-6805-6_40]

Clinical manifestations in neuropathologically defined subgroups of vascular dementia

AIMS

To study cardio-cerebrovascular disease and clinical features, such as falls, dizziness/unsteadiness, urinary incontinence, hallucinations/delusions and delirium in neuropathologically defined subgroups of vascular Dementia (VaD): pure Small Vessel Dementia (SVD), combined SVD and Alzheimer's disease (SVD-AD), pure Large Vessel Dementia (LVD) and pure Hypoxic Hypoperfusive Dementia (HHD), and to analyse the clinical differences between these groups.

MATERIALS AND METHODS

From 175 consecutive cases with neuropathologically verified VaD cases with pure SVD (n = 36) and SVD-AD (n = 38) with varying severity of AD pathology were selected and studied with respect to cardio-cerebrovascular and other clinical features. Furthermore, a comparison between pure SVD, pure LVD (n = 7) and pure HHD (n = 6) was made.

RESULTS

Neither cardiovascular symptoms, hypertension, Transitoric Ischemic Attacks (TIA) nor complete cerebrovascular lesions (CVL) differed significantly between the pure SVD and SVD-AD groups. However, a wide variation of clinical features were reported. The prevalence of cardiovascular features varied markedly in the pure groups, with the highest prevalence consistently found in the LVD group. Hypertension was common in the pure LVD and SVD-groups, while it was a rare finding in the HHD-group. TIA and/or CVL were, as expected, most common in the LVD-group.

CONCLUSION

In conclusion, this longitudinal and retrospective study of VaD shows important clinical similarities as well as differences between pathologically defined subgroups. Hopefully these findings will contribute to a better understanding of etiopathogenetic and diagnostic issues and form a solid basis for possible treatment strategies in VaD.

A clinico-pathological study of heart and brain lesions in vascular dementia

All vascular dementia (VaD) cases, neuropathologically verified in a longitudinal prospective dementia project, were classified according to the vascular brain lesion type and related to the dementia type and cardiovascular pathology. From 1976 to 1995, there were 175 VaD cases, 49 of which were pure, without Alzheimer pathology and only one type of cerebrovascular lesion. Furthermore, it was found that 6 cases suffered hypoxic hypoperfusive disease, while 7 were found to have large vessel disease and 36 small vessel disease. In addition to Alzheimer pathology, more than one type of vascular brain pathology was found in the remaining 126 cases. In these cases, diagnosed in accordance with the predominant type of VaD, hypoxic-hypoperfusive lesions were found in 55, large vessel lesions in 50 and small vessel lesions in 110 cases. It should be stressed that 87% of all cases with hypoxic hypoperfusive lesions also had Alzheimer pathology. Cardiovascular and aortic pathologies were more prevalent in small vessel dementia than in the other VaD groups. Clinically diagnosed arterial hypertension was significantly associated with small vessel dementia, but not with hypoxic-hypoperfusive dementia. Cardiovascular symptoms varied considerably in frequency between different dementia groups. VaD is a heterogeneous group regarding lesions caused by different pathophysiological mechanisms and with different combinations of brain pathologies. It is therefore necessary to identify the various types of vascular brain lesions for a correlation with clinical symptoms and for diagnostic purposes in the search for risk factors and therapeutic strategies.

Loss of human hippocampal adenosine A1 receptors in dementia: evidence for lack of specificity

The density of hippocampal adenosine A1 receptors was measured in autopsy samples of six patients with dementia with either Alzheimer (three) or sclerosis type pathology (three) in hippocampus and six control patients. Kinetic parameters (Bmax and KD) were determined by means of quantitative autoradiography using [3H]8-cyclopentyl-1 ,3-dipropylxanthine as a radioligand. A significant 50% reduction of CA1 adenosine A1 receptors was observed in patients with dementia independent of the specific pathology. These results suggest that loss of hippocampal adenosine A1 receptors in dementia is not specific for Alzheimer type pathology.

Positron emission tomography in vascular dementia

BACKGROUND

Vascular dementia (VaD) is an ill-defined entity. It is not known how acute brain failure related to stroke becomes chronic leading to dementia.

PURPOSE

The present study investigates whether positron emission tomography (PET) can detect different metabolic patterns in VaD.

PATIENTS AND METHODS

Four groups of stroke patients were selected. The PET findings of 14 stroke patients with multiple large infarcts and dementia (MID) and 14 without dementia (MS) were compared. Sixteen stroke patients with lacunes, leukoaraiosis and dementia (LD) were assessed against nine without dementia (LS). The PET examination utilised the 15-O-steady-state technique in order to determine regional cerebral blood flow (rCBF), regional oxygen extraction rate (rOER) and regional cerebral metabolic rate for oxygen (rCMRO2) in different pre-established cortical, subcortical and cerebellar regions.

RESULTS

Decreased coupled mean rCBF and rCMRO2 with comparable rOER values were observed in all cerebral regions except in the cerebellum of the MID compared to the MS group. In the LD group mean rCBF and rCMRO2 were decreased with increased rOER in all cerebral regions except in the cerebellum compared to the LS group.

CONCLUSIONS

The PET findings in demented patients with multiple large infarcts are in agreement with the concept of multi-infarct dementia. In demented patients with lacunes and leukoaraiosis, the PET pattern suggests a state of misery perfusion not only in the deep structures but also in the whole cerebral cortex. The present PET study argues that there are at least two possible mechanisms that can explain the occurrence of VaD in stroke patients.