Biomedical subjects
Publications and source records attributed to C Ballard.
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BACKGROUND: Wandering occurs in 15-60% of people with dementia. Psychosocial interventions rather than pharmacological methods are recommended, but evidence for their effectiveness is limited and there are ethical concerns associated with some non-pharmacological approaches, such as electronic tracking devices. OBJECTIVE: To determine the clinical and cost effectiveness and acceptability of non-pharmacological interventions to reduce wandering in dementia. DESIGN: A systematic review to evaluate effectiveness of the interventions and to assess acceptability and ethical issues associated with their use. The search and review strategy, data extraction and analysis followed recommended guidance. Papers of relevance to effectiveness, acceptability and ethical issues were sought. RESULTS: (i) Clinical effectiveness. Eleven studies, including eight randomised controlled trials, of a variety of interventions, met the inclusion criteria. There was no robust evidence to recommend any intervention, although there was some weak evidence for exercise. No relevant studies to determine cost effectiveness met the inclusion criteria. (ii) Acceptability/ethical issues. None of the acceptability papers reported directly the views of people with dementia. Exercise and music therapy were the most acceptable interventions and raised no ethical concerns. Tracking and tagging devices were acceptable to carers but generated considerable ethical debate. Physical restraints were considered unacceptable. CONCLUSIONS: In order to reduce unsafe wandering high quality research is needed to determine the effectiveness of non-pharmacological interventions that are practically and ethically acceptable to users. It is important to establish the views of people with dementia on the acceptability of such interventions prior to evaluating their effectiveness through complex randomised controlled trials.
BACKGROUND: The objective of this comparative neuropathologic study was to determine the extent to which dementia with Lewy bodies (DLB) and Parkinson disease dementia (PDD) are distinct entities or part of a continuum with respect to the duration of parkinsonism. METHODS: We evaluated the relationship between cortical alpha-synuclein pathology, plaques (Consortium to Establish a Registry for Alzheimer's Disease [CERAD]), tangles (Braak staging), and cholinergic deficits (choline acetyltransferase in temporal cortex) in 57 prospectively assessed patients (29 DLB, 28 PDD), confirmed at autopsy. The PDD group was divided according to the median duration of parkinsonism prior to dementia. RESULTS: There was an association between longer duration of parkinsonism prior to dementia and less severe cortical alpha-synuclein pathology (chi(2) 10.4, df 2, p = 0.006) and lower CERAD plaque scores (chi(2) 26.6, df 9, p = 0.002), but not Braak staging. These findings were confirmed in a further correlation analysis, which also identified an unexpected correlation between more pronounced cortical cholinergic deficits and longer duration of parkinsonism prior to dementia (R = -0.37, p = 0.04). CONCLUSION: While there is a clear relationship between the duration of Parkinson disease prior to the onset of dementia and key neuropathologic and neurochemical characteristics, there is a gradation of these differences across the dementia with Lewy bodies/Parkinson disease dementia spectrum and the findings do not support an arbitrary cut-off between the two disorders.
The Structural Proteomics In Europe (SPINE) consortium contained a workpackage to address the automated X-ray analysis of macromolecules. The aim of this workpackage was to increase the throughput of three-dimensional structures while maintaining the high quality of conventional analyses. SPINE was able to bring together developers of software with users from the partner laboratories. Here, the results of a workshop organized by the consortium to evaluate software developed in the member laboratories against a set of bacterial targets are described. The major emphasis was on molecular-replacement suites, where automation was most advanced. Data processing and analysis, use of experimental phases and model construction were also addressed, albeit at a lower level.
BACKGROUND: Aggression, agitation or psychosis occur in the majority of people with dementia at some point in the illness. There have been a number of trials of atypical antipsychotics to treat these symptoms over the last five years, and a systematic review is needed to evaluate the evidence in a balanced way. OBJECTIVES: To determine whether evidence supports the use of atypical antipsychotics for the treatment of aggression, agitation and psychosis in people with Alzheimer's disease. SEARCH STRATEGY: The trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 7 December 2004 using the terms olanzapine, quetiapine, risperidone, clozapine, amisulpride, sertindole, zotepine, aripiprazole, ziprasidone. This Register contains articles from all major healthcare databases and many ongoing trials databases and is updated regularly. SELECTION CRITERIA: Randomised, placebo-controlled trials, with concealed allocation, where dementia and psychosis and/or aggression were assessed. DATA COLLECTION AND ANALYSIS: 1. Two reviewers extracted data from included trials2. Data were pooled where possible, and analysed using appropriate statistical methods3. Analysis included patients treated with an atypical antipsychotic, compared with placebo MAIN RESULTS: Sixteen placebo controlled trials have been completed with atypical antipsychotics although only nine had sufficient data to contribute to a meta-analysis and only five have been published in full in peer reviewed journals. No trials of amisulpiride, sertindole or zotepine were identified which met the criteria for inclusion. The included trials led to the following results:1. There was a significant improvement in aggression with risperidone and olanzapine treatment compared to placebo.2. There was a significant improvement in psychosis amongst risperidone treated patients.3. Risperidone and olanzpaine treated patients had a significantly higher incidence of serious adverse cerebrovascular events (including stroke), extra-pyramidal side effects and other important adverse outcomes.4. There was a significant increase in drop-outs in risperidone (2 mg) and olanzapine (5-10 mg) treated patients.5. The data were insufficient to examine impact upon cognitive function. AUTHORS' CONCLUSIONS: Evidence suggests that risperidone and olanzapine are useful in reducing aggression and risperidone reduces psychosis, but both are associated with serious adverse cerebrovascular events and extra-pyramidal symptoms. Despite the modest efficacy, the significant increase in adverse events confirms that neither risperidone nor olanzapine should be used routinely to treat dementia patients with aggression or psychosis unless there is marked risk or severe distress. Although insufficient data were available from the considered trials, a meta-analysis of seventeen placebo controlled trials of atypical neuroleptics for the treatment of behavioural symptoms in people with dementia conducted by the Food and Drug Administration (using data not in the public domain) suggested a significant increase in mortality (OR 1.7).
Cholinesterase inhibition in patients with Alzheimer's disease (AD) may affect heart rate, sometimes inducing bradycardia. Additional cardiac safety considerations apply in patients with dementia with Lewy bodies (DLB) and Parkinson's disease (PDD), in whom cardiovascular autonomic nervous system dysfunction is common. We conducted a review of the safety data available for rivastigmine in these two conditions. A modest reduction in the mean heart rate of 1.5-2 bpm was seen. No clinically meaningful treatment differences in bradycardia or ECG abnormalities were apparent. Compared with placebo, rivastigmine appeared to be associated with fewer vascular disorder adverse events (AEs) (p = 0.002) and fewer AEs of syncope (p = 0.018) in PDD patients (n = 541). A smaller randomised, placebo-controlled study of rivastigmine in DLB (n = 120) showed similar findings. Rivastigmine appears to have a favourable cardiac safety profile in PDD and DLB patients.
OBJECTIVES: To determine the effectiveness and cost-effectiveness of non-pharmacological interventions (excluding subjective barriers) in the prevention of wandering in people with dementia, in comparison with usual care, and to evaluate through the review and a qualitative study the acceptability to stakeholders of such interventions and identify ethical issues associated with their use. DATA SOURCES: Major electronic databases were searched up until 31 March 2005. Specialists in the field. REVIEW METHODS: Selected studies were assessed and analysed. The results of two of the efficacy studies that used similar interventions, designs and outcome measures were pooled in a meta-analysis; results for other studies which reported standard deviations were presented in a forest plot. Owing to a lack of cost-effectiveness data, a modelling exercise could not be performed. Four focus groups were carried out with relevant stakeholders (n = 19) including people with dementia and formal and lay carers to explore ethical and acceptability issues in greater depth. Transcripts were coded independently by two reviewers to develop a coding frame. Analysis was via a thematic framework approach. RESULTS: Ten studies met the inclusion criteria (multi-sensory environment, three; music therapy, one; exercise, one; special care units, two; aromatherapy, two; behavioural intervention, one). There was no robust evidence to recommend any non-pharmacological intervention to reduce wandering in dementia. There was some evidence, albeit of poor quality, for the effectiveness of exercise and multi-sensory environment. There were no relevant studies to determine the cost-effectiveness of the interventions. Findings from the narrative review and focus groups on acceptability and ethical issues were comparable. Exercise and distraction therapies were the most acceptable interventions and raised no ethical concerns. All other interventions were considered acceptable except for physical restraints, which were considered unacceptable. Considerable ethical concerns exist with the use of electronic tagging and tracking devices and physical barriers. Existing literature ignores the perspectives of people with dementia. The small number of participants with dementia expressed caution regarding the use of unfamiliar technology. Balancing risk and risk assessment was an important theme for all carers in the management of wandering. CONCLUSIONS: There is no robust evidence so far to recommend the use of any non-pharmacological intervention to reduce or prevent wandering in people with dementia. High-quality studies, preferably randomised controlled trials, are needed to determine the clinical and cost-effectiveness of non-pharmacological interventions that allow safe wandering and are considered practically and ethically acceptable by carers and people with dementia. Large-scale, long-term cohort studies are needed to evaluate the morbidity and mortality associated with wandering in dementia for people both in the community and in residential care. Such data would inform future long-term cost-effectiveness studies.
BACKGROUND AND PURPOSE: The apolipoprotein E4 allele (APOE4) associates with increased dementia risk, and hypertension may associate with mild cognitive deficits. We examined whether nondemented stroke patients with (1) a prestroke history of hypertension and (2) APOE4 were more cognitively impaired at 3 months after stroke. METHODS: A total of 257 participants were genotyped and outcomes from neuropsychological evaluations analyzed using regression. RESULTS: Total Cambridge Assessment for Mental Disorders in the Elderly (CAMCOG) and speed of working memory significantly associated with hypertension. No outcomes significantly associated with APOE4. CONCLUSIONS: Subjects with prestroke hypertension had more impaired global cognition and slower access to information held in working memory.
Choline acetyltransferase in temporal cortex was evaluated as a marker of cholinergic function in autopsied dementia cases (9 vascular dementia [VaD] cases, 12 "mixed" VaD and Alzheimer disease [AD] cases, 10 AD cases, 12 control subjects). Patients with AD (t = 2.5, p = 0.02) and "mixed" VaD and AD (t = 3.8, p = 0.001) had greater cholinergic deficits than age-matched control subjects and patients with "pure" VaD. The absence of cholinergic deficits in "pure" VaD may be relevant to the pharmacologic treatment of these patients.
OBJECTIVE: To determine whether individuals with Alzheimer's disease (AD) and the K variant allele of butyrylcholinesterase have a slower rate of cognitive decline than those without the K variant allele of butyrylcholinesterase. METHOD: The cognitive status of 339 community based subjects with AD was assessed with the Mini Mental State Examination at baseline and yearly over a three year follow up period. The rates of cognitive decline of subjects with and without the K variant allele were compared. RESULT: Presence of the K allele was associated with a slower average rate of cognitive decline in subjects with severe AD. CONCLUSIONS: This finding is consistent with the suggestion that the K variant of butyrylcholinesterase has an important role in disease progression in AD, and this may have implications for treatment.
BACKGROUND: Carotid sinus syndrome (CSS) is a common cause of syncope in older persons. There appears to be a high prevalence of carotid sinus hypersensitivity (CSH) in patients with dementia with Lewy bodies (DLB) but not in Alzheimer's disease. OBJECTIVE: To compare the prevalence of CSH in DLB and Alzheimer's disease, and to determine whether there is an association between CSH induced hypotension and brain white matter hyperintensities on magnetic resonance imaging (MRI). METHODS: Prevalence of CSH was compared in 38 patients with DLB (mean (SD) age, 76 (7) years), 52 with Alzheimer's disease (80 (6) years), and 31 case controls (73 (5) years) during right sided supine carotid sinus massage (CSM). CSH was defined as cardioinhibitory (CICSH; >3 s asystole) or vasodepressor (VDCSH; >30 mm Hg fall in systolic blood pressure (SBP)). T2 weighted brain MRI was done in 45 patients (23 DLB, 22 Alzheimer). Hyperintensities were rated by the Scheltens scale. RESULTS: Overall heart rate response to CSM was slower (RR interval = 3370 ms (640 to 9400)) and the proportion of patients with CICSH greater (32%) in DLB than in Alzheimer's disease (1570 (720 to 7800); 11.1%) or controls (1600 (720 to 3300); 3.2%) (p<0.01)). The strongest predictor of heart rate slowing and CSH was a diagnosis of DLB (Wald 8.0, p<0.005). The fall in SBP during carotid sinus massage was greater with DLB (40 (22) mm Hg) than with Alzheimer's disease (30 (19) mm Hg) or controls (24 (19) mm Hg) (both p<0.02). Deep white matter hyperintensities were present in 29 patients (64%). In DLB, there was a correlation between magnitude of fall in SBP during CSM and severity of deep white matter changes (R = 0.58, p = 0.005). CONCLUSIONS: Heart rate responses to CSM are prolonged in patients with DLB, causing hypotension. Deep white matter changes from microvascular disease correlated with the fall in SBP. Microvascular pathology is a key substrate of cognitive impairment and could be reversible in DLB where there are exaggerated heart rate responses to carotid sinus stimulation.
Voxel-based morphometry (VBM) has already been applied to MRI scans of patients with Alzheimer's disease (AD). The results of these studies demonstrated atrophy of the hippocampus, temporal pole, and insula, but did not describe any global brain changes or atrophy of deep cerebral structures. We propose an optimized VBM method, which accounts for these shortcomings. Additional processing steps are incorporated in the method, to ensure that the whole spectrum of brain atrophy is visualized. A local group template was created to avoid registration bias, morphological opening was performed to eliminate cerebrospinal fluid voxel misclassifications, and volume preserving modulation was used to correct for local volume changes. Group differences were assessed and thresholded at P < 0.05 (corrected). Our results confirm earlier findings, but additionally we demonstrate global cortical atrophy with sparing of the sensorimotor cortex, occipital poles, and cerebellum. Moreover, we show atrophy of the caudate head nuclei and medial thalami. Our findings are in full agreement with the established neuropathological descriptions, offering a comprehensive view of atrophy patterns in AD.
OBJECTIVES: To determine whether parkinsonian symptoms in dementia with Lewy bodies (DLB) are associated with greater atrophy of the caudate nucleus in comparison with patients with Alzheimer's disease (AD) and vascular dementia (VaD). METHODS: T1weighted MR scans were acquired in elderly patients with DLB, AD, VaD, and healthy controls. Normalised volumetric measurements of the caudate nucleus were obtained and parkinsonian symptoms rated using Hoehn and Yahr staging. RESULTS: There were no significant differences in the volume of the caudate nucleus between patients with dementia. However, the left caudate volume was significantly reduced in AD and DLB compared with controls. Parkinsonian symptoms did not correlate with caudate nucleus volume. CONCLUSIONS: Parkinsonian symptoms in DLB may be more closely coupled to neurochemical rather than structural changes in the caudate nucleus, and volumetric MRI analysis of caudate nucleus does not discriminate between patients with DLB, AD, and VaD.
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Dementia with Lewy bodies (DLB) is associated with occipital changes in blood flow and metabolism, but structural changes in this region have not previously been assessed. The authors performed volumetric MRI measurement of the occipital lobe blind to the diagnosis in 23 subjects with DLB, 25 with AD, and 24 age-matched control subjects. There were no significant differences between groups in occipital lobe volume. The authors conclude gross structural changes in the occipital lobe do not occur in patients with mild to moderate DLB or AD.
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The authors determined rates of brain atrophy, as assessed by the boundary shift integral on serial MRI, in patients with dementia with Lewy Bodies (DLB, n = 10), AD (n = 9), vascular dementia (VaD, n = 9), and age-matched controls (n = 20). Mean % +/- SD atrophy rates per year were as follows: DLB, 1.4 +/- 1.1; AD, 2.0 +/- 0.9; VaD, 1.9 +/- 1.1; and controls, 0.5 +/- 0.7. Dementia subjects had higher rates than controls (p < 0.001), but there were no significant differences between the three dementia groups. The authors found accelerating atrophy with increasing severity of cognitive impairment, further emphasizing the need for early diagnosis and intervention in dementia.
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