A Factor Analytic Approach to Symptom Patterns in Dementia

Previous publications have shown a high diagnostic sensitivity and specificity of three short clinical rating scales for Alzheimer's disease (AD), frontotemporal dementia (FTD), and vascular dementia (VaD) validated against neuropathological (NP) diagnoses. In this study, the aim was to perform an exploratory factor analysis of the items in these clinical rating scales. The study included 190 patients with postmortem diagnoses of AD (n = 74), VaD (n = 33), mixed AD/VaD (n = 31), or FTD (n = 52). The factor analysis produced three strong factors. Factor 1 contained items describing cerebrovascular disease, similar to the Hachinski Ischemic Score. Factor 2 enclosed major clinical characteristics of FTD, and factor 3 showed a striking similarity to the AD scale. A fourth symptom cluster was described by perception and expression of emotions. The factor analyses strongly support the construct validity of the diagnostic rating scales

Posture and brain function in dementia. A study with special reference to orthostatic hypotension.

Orthostatic hypotension (OH) is believed to be an important cause of cerebral hypoperfusion, leading to chronic fatigue, blurred vision, unsteadiness, dizziness and sometimes syncope. It may also result in episodes of confusion, falls and fractures. The coupling between OH and organic dementia is not clear. Our findings in a large group of patients with Alzheimer's disease, vascular- and frontotemporal dementia has shown a higher prevalence of OH than is seen in healthy elderly people. To examine the blood pressure we used a standardized orthostatic test. The systolic blood pressure drop varied from 20 to about 100 mm Hg. In about 30% of the patients the blood pressure drop did not appear until after 5 minutes or later in the upright position. About 50% of the patients did not report or show any orthostatic symptoms despite marked blood pressure drops. Falls and multiple fractures were significantly higher in the orthostatic patients. The aim of the study was also to investigate whether postural challenge and OH alters the regional cerebral blood flow (rCBF). The results showed significant and consistent lower values in frontal areas during head-up tilt than during supine position. In autopsy verified Alzheimer-cases, additional white matter disease (wmd) was found in about 2/3 of the patients. A highly significant decrease of blood pressure was seen during the progression of dementia in the Alzheimer-patients, especially in those with wmd. The suggested cause of this regional white matter hypoperfusion is the interaction of non-occlusive small vessel sclerosis with recurrent episodes of low blood pressure. Our results also indicate, that in patients with orthostatic symptoms, the cerebral autoregulation seemed more vulnerable than in those without symptoms. Recognition of OH as well as low blood pressure is crucial, and as a risk factor it may not only be treatable but also preventable

Prevalence of dementia subtypes: A 30-year retrospective survey of neuropathological reports.

We investigated the distribution of neuropathologically defined dementia subtypes among individuals with dementia disorder. The neuropathological reports were studied on all patients (n=524; 55.3% females; median age 80, range 39-102 years) with clinically diagnosed dementia disorder who underwent complete autopsy including neuropathological examination within the Department of Pathology at the University Hospital in Lund, Sweden, during the years 1974-2004. The neuropathological diagnosis was Alzheimer's disease (AD) in 42.0% of the cases, vascular dementia (VaD) in 23.7%, dementia of combined Alzheimer and vascular pathology in 21.6%, and frontotemporal dementia in 4.0% of the patients. The remaining 8.8% of the patients had other dementia disorders, including combinations other than combined Alzheimer and vascular pathology. The registered prevalence of dementia subtypes depends on many variables, including referral habits, clinical and neuropathological judgments and diagnostic traditions, all of these variables potentially changing over time. This, however, does not seem to obscure the delineation of the major dementia subgroups. In this material of 30 years from Lund in the south of Sweden, AD by far dominated among dementia subtypes, while cerebrovascular pathology corresponded with the dementia disorder, either entirely or partly, in almost half of the demented patients

Functional activation of the frontal lobes. Regional cerebral blood flow findings in normals and in patients with frontal lobe dementia performing a word fluency test

The present study examined the utility of the Word Fluency Test (WFT) as a frontal-lobe-activating test in brain imaging. Regional cerebral blood flow (rCBF) was measured during rest and during the WFT in 49 healthy volunteers and in 15 patients with frontal lobe dementia (FLD). The results showed a highly significant frontal lobe activation in 85% of the normal subjects. This finding was not related to age or to the level of performance on the WFT. A significant frontal activation was seen in 13 of the 15 FLD patients. The frontal flow increase did not reach normal levels, and was not related to age, illness duration or severity of clinical symptoms. The results suggest that the WFT is an ideal test to use in conjunction with functional imaging in normals as well as in patients with organic dementia

Alzheimer's disease (AD) with and without white matter pathology-clinical identification of concurrent cardiovascular disorders.

Clinical vascular features, either as manifest vascular disease or as cardiovascular risk factors were compared in AD with and without neuropathological white matter disease (WMD). The aim of the study was to investigate whether the presence of WMD and the severity of either AD pathology or WMD were associated with different cardiovascular profiles. A total of 44 AD cases were retrospectively studied. All the cases were neuropathologically diagnosed as AD with WMD (n = 22) and as AD without WMD (n = 22), respectively. The patients' medical records were studied with regard to their medical history and to somatic and neurological findings including arrhythmia, congestive heart failure, angina, myocardial infarctions, signs of TIA/stroke, diabetes mellitus, and blood pressure abnormalities, such as hypertension and orthostatic hypotension. In AD-WMD, hypertension, orthostatic hypotension as well as dizziness/unsteadiness were significantly more common than in AD without WMD. Cardiovascular symptoms were more frequent in AD-WMD than in the other group, though the difference did not reach statistical significance. Hypothetically, abnormal and unstable blood pressure levels underlie recurrent cerebral hypoperfusion, which may in turn leave room for the development of WMD. Furthermore, dizziness/unsteadiness may be a symptom reflecting the presence of WMD. (c) 2006 Elsevier Ireland Ltd. All rights reserved

Frontotemporal dementia – Differentiation from Alzheimer's disease

Organic dementia is dominated by primary degenerative disorders such as Alzheimer’s disease (AD) and frontotemporal dementia (FTD). FTD is a distinct clinical syndrome with behavioural, personality, emotional and language disturbances preceding the cognitive decline. This clinical presentation is distinctly different from that of AD which is characterized by early cognitive changes, such as memory impairment, aphasia and apraxia, and a relatively preserved personality and behaviour. The differences between these two conditions reflect the predominant topographic distribution of brain pathology. The differences in clinical profiles and treatment strategies will be highlighted. In both disorders loss of functional ability, development of behavioural disturbances and dependency impose heavy demands on family and other caregivers. This presentation will concentrate on early recognition and diagnosis, using systematic clinical evaluation, neuropsychological testing and different brain imaging methods. This is important for a successful development of therapeutic strategies for both cognitive and behavioural symptoms in FTD and AD