Parkinson Disease: O'Brien JT

McKeith IG, Dickson DW, Lowe J, Emre M, O'Brien JT, Feldman H, Cummings J, Duda JE, Lippa C, Perry EK, Aarsland D, Arai H, Ballard CG, Boeve B, Burn DJ, Costa D, Del Ser T, Dubois B, Galasko D, Gauthier S, Goetz CG, Gomez-Tortosa E, Halliday G, Hansen LA, Hardy J, Iwatsubo T, Kalaria RN, Kaufer D, Kenny RA, Korczyn A, Kosaka K, Lee VM, Lees A, Litvan I, Londos E, Lopez OL, Minoshima S, Mizuno Y, Molina JA, Mukaetova-Ladinska EB, Pasquier F, Perry RH, Schulz JB, Trojanowski JQ, Yamada M, Anonymous00346. · Institute for Ageing and Health, University of Newcastle upon Tyne, UK. · Neurology. · Pubmed #16237129 No free full text.

Abstract: The dementia with Lewy bodies (DLB) Consortium has revised criteria for the clinical and pathologic diagnosis of DLB incorporating new information about the core clinical features and suggesting improved methods to assess them. REM sleep behavior disorder, severe neuroleptic sensitivity, and reduced striatal dopamine transporter activity on functional neuroimaging are given greater diagnostic weighting as features suggestive of a DLB diagnosis. The 1-year rule distinguishing between DLB and Parkinson disease with dementia may be difficult to apply in clinical settings and in such cases the term most appropriate to each individual patient should be used. Generic terms such as Lewy body (LB) disease are often helpful. The authors propose a new scheme for the pathologic assessment of LBs and Lewy neurites (LN) using alpha-synuclein immunohistochemistry and semiquantitative grading of lesion density, with the pattern of regional involvement being more important than total LB count. The new criteria take into account both Lewy-related and Alzheimer disease (AD)-type pathology to allocate a probability that these are associated with the clinical DLB syndrome. Finally, the authors suggest patient management guidelines including the need for accurate diagnosis, a target symptom approach, and use of appropriate outcome measures. There is limited evidence about specific interventions but available data suggest only a partial response of motor symptoms to levodopa: severe sensitivity to typical and atypical antipsychotics in approximately 50%, and improvements in attention, visual hallucinations, and sleep disorders with cholinesterase inhibitors.

Burn DJ, O'Brien JT. · Department of Neurology, Regional Neurosciences Centre, Newcastle General Hospital, United Kingdom. · Mov Disord. · Pubmed #14502661 No free full text.

Abstract: Neuropsychiatric symptoms, including dementia, frequently coexist with parkinsonian disorders and may cause diagnostic confusion as well as management problems. Functional imaging studies include single photon emission computerised tomography (SPECT), positron emission tomography (PET), proton magnetic resonance spectroscopy, diffusion tensor imaging, and functional magnetic resonance imaging. This review addresses the utility of these techniques, from the clinician's perspective, focusing on the most common causes of parkinsonism and cognitive impairment, Parkinson's disease with dementia, dementia with Lewy bodies, and Alzheimer's disease. The potential and limitations of these techniques for accurate and early diagnosis, monitoring disease progression, and establishing the pathophysiological basis underlying key clinical features are considered. The development of new probes for SPECT and PET cameras capable of labeling protein aggregates (e.g., beta-amyloid) will offer exciting new insights into the spatial and temporal pattern of pathophysiological processes. Longitudinal studies with clinicopathological correlation represent the "gold standard" for fully evaluating functional imaging techniques.

McKeith IG, Burn DJ, Ballard CG, Collerton D, Jaros E, Morris CM, McLaren A, Perry EK, Perry R, Piggott MA, O'Brien JT. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle, UK. · Semin Clin Neuropsychiatry. · Pubmed #12567332 No free full text.

Abstract: The objective was to summarize recent findings about the clinical features, diagnosis and investigation of dementia with Lewy (DLB) bodies, together with its neuropathology, neurochemistry and genetics. Dementia with Lewy bodies (DLB) is a primary, neurodegenerative dementia sharing clinical and pathological characteristics with both Parkinson's disease (PD) and Alzheimer's disease (AD). Antiubiquitin immunocytochemical staining, developed in the early 1990s, allowed the frequency and distribution of cortical LBs to be defined. More recently, alpha-synuclein antibodies have revealed extensive neuritic pathology in DLB demonstrating a neurobiological link with other "synucleinopathies" including PD and multiple system atrophy (MSA). The most significant correlates of cognitive failure in DLB appear to be with cortical LB and Lewy neurites (LNs) rather than Alzheimer type pathology. Clinical diagnostic criteria for DLB, published in 1996, have been subjected to several validation studies against autopsy findings. These conclude that although diagnostic specificity is high (range 79- 100%, mean 92%), sensitivity is lower (range 0- 83 %, mean, 49%). Improved methods of case detection are therefore required. Fluctuating impairments in attention, visual recognition and construction are more indicative of DLB than AD. Relative preservation of medial temporal lobe volume on structural MRI and the use of SPECT tracers for regional blood flow and the dopamine transporter are the most reliable current biomarkers for DLB. There are no genetic or CSF tests recommended for the diagnosis of DLB at present. Between 15 and 20% of all elderly demented cases reaching autopsy have DLB, making it the most common cause of degenerative dementia after AD. Exquisite, not infrequently fatal, sensitivity to neuroleptic drugs and encouraging reports of the effects of cholinesterase inhibitors on cognitive, psychiatric and neurological features, mean that an accurate diagnosis of DLB is more than merely of academic interest. Dementia developing late in the course of PD shares many of the same clinical and pathological characteristics.

Firbank MJ, Harrison RM, O'Brien JT. · Institute for Ageing and Health, Newcastle General Hospital, Newcastle upon Tyne, UK. · Dement Geriatr Cogn Disord. · Pubmed #12145453 No free full text.

Abstract: We reviewed the literature of proton magnetic resonance spectroscopy (MRS) in dementia and Parkinson's disease (PD) and quantitatively compared the reported values of the markers N-acetyl aspartate (NAA), choline, and myo-Inositol between control and disease groups. We analysed a total of 27 reports in dementia. Combining the quantitative data from these showed a relative decrease of 15% in NAA level in the temporal lobe tissue in patients with Alzheimer's disease (AD) compared with controls. The rest of the brain showed a seemingly uniform 10% decrease in NAA levels in AD compared with controls. myo-Inositol was raised by about 15%, again uniformly throughout the brain, but there was no evidence for changed levels of choline. We found 15 reports of MRS in PD, which show a small decrease (5%) in the NAA level in the lentiform nucleus compared with controls. In progressive supranuclear palsy (PSP), there is a greater decrease in NAA levels in the frontal region and the lentiform nucleus. This may aid in the diagnosis of PSP. Further research is needed to determine spectroscopic changes in other dementias, to monitor how markers change with disease progression and to establish clinical utility.

Taylor JP, Rowan EN, Lett D, O'Brien JT, McKeith IG, Burn DJ. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK. · J Neurol Neurosurg Psychiatry. · Pubmed #18586866 No free full text.

Abstract: BACKGROUND: Postural instability gait difficulty (PIGD) motor phenotype in Parkinson's disease (PD) is associated with a faster rate of cognitive decline than in tremor dominant cases and may be a risk factor for incident dementia. People with PD display attentional deficits; however, it is not clear whether attentional deficits in patients with non-demented PD are associated with (i) PIGD phenotype and/or (ii) subsequent cognitive decline. AIMS: (i) To examine rates of cognitive decline (Mini-Mental State Examination (MMSE) and Cambridge Cognitive Examination (CAMCOG)) over 3 years in subjects with non-demented PD aged over 65 years, (ii) using Cognitive Drug Research computerised assessment test battery, determine the rate of change in power of attention (PoA) scores over time (sum of mean choice reaction time, simple reaction time and digit vigilance reaction time scores), (iii) determine whether the PIGD phenotype is associated with changes in PoA and (iv) establish whether baseline PoA is associated with subsequent cognitive decline. RESULTS: 14 subjects (38%) were classified as PIGD motor phenotype at baseline. Cognitive decline was greater in PIGD compared with non-PIGD subjects (p < or = 0.02). PIGD phenotype was not associated with baseline PoA score although it was associated with subsequent worsening in PoA (mean PoA increase/year: non-PIGD subjects 11.4 ms; PIGD subjects 244.0 ms; p = 0.01). Higher baseline PoA scores were associated with greater cognitive decline (MMSE, p = 0.03; CAMCOG, p = 0.05) independent of PIGD status. CONCLUSION: PIGD phenotype and attention deficits are independently associated with a greater rate of cognitive decline in patients with non-demented PD. We propose that subtle attentional deficits in patients with non-demented PD predict subsequent cognitive impairment.

Molloy SA, Rowan EN, O'Brien JT, McKeith IG, Wesnes K, Burn DJ. · Institute of Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, UK. · J Neurol Neurosurg Psychiatry. · Pubmed #16952917 No free full text.

Abstract: BACKGROUND: Levodopa (L-dopa) is the gold standard treatment for Parkinson's disease, but a lack of clear efficacy combined with a perceived liability to neuropsychiatric side effects has limited L-dopa use in patients with parkinsonism and dementia. Therefore, the effect of L-dopa on the cognitive profile of dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD) is unclear. AIM: To ascertain the acute and long-term effects of L-dopa on aspects of attention and cognition in patients with DLB and PDD, and to compare these with the effects in Parkinson's disease. METHOD: Baseline cognitive and motor function was assessed off L-dopa in patients with Parkinson's disease (n = 22), PDD (n = 27) and DLB (n = 11) using standard "bedside" measures and a computerised programme detecting reaction times and accuracy. All patients then underwent an acute L-dopa challenge with subsequent subjective and objective analysis of alertness, verbal recall, reaction times and accuracy. The same parameters were measured after 3 months on L-dopa to assess the prolonged effect. RESULTS: Acute L-dopa challenge considerably improved motor function and subjective alertness in all patients without compromising either reaction times or accuracy, but increased fluctuations were noted in both groups with dementia. Neuropsychiatric scores improved in patients with Parkinson's disease both with and without dementia on L-dopa at 3 months. Although patients with Parkinson's disease also had better mean global cognitive function at this time, mean verbal attention and memory deteriorated, and patients with PDD had slower reaction times in some tests. No patient had a marked deterioration over this time. Patients with DLB did not experience any adverse cognitive or neuropsychiatric effects after 3 months of L-dopa treatment. CONCLUSION: The use of L-dopa in patients with parkinsonism with dementia does not adversely affect cognitive function.

Pakrasi S, Thomas A, Mosimann UP, Cousins DA, Lett D, Burn DJ, O'Brien JT, McKeith IG. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, UK. · Int J Geriatr Psychiatry. · Pubmed #16858742 No free full text.

Abstract: INTRODUCTION: There is little data on stopping cholinesterase inhibitors in Dementia with Lewy bodies (DLB). Equally, it is not known if increasing the dose of cholinesterase inhibitors may help neuropsychiatric symptoms in advanced DLB. METHOD: We conducted an open label trial with donepezil involving 16 patients with LBD when the dose was reduced and treatment stopped over 4 weeks. Another 7 patients were given a trial of an increased dose of donepezil (15 mg) to resolve rehyphen;emergent neuropsychiatric symptoms. RESULTS: The slow discontinuation protocol was well tolerated in advanced DLB. Five of the seven patients given a trial of a higher dose of donepezil were rated as clinically improved after 12 weeks treatment. CONCLUSION: Cholinesterase inhibitors can be discontinued slowly in advanced DLB. Increasing the dose of donepezil may be of benefit to some patients with DLB who experience a recurrence in their neuropsychiatric symptoms.

Colloby SJ, O'Brien JT, Fenwick JD, Firbank MJ, Burn DJ, McKeith IG, Williams ED. · Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle- upon-Tyne NE4 6BE, UK. · Neuroimage. · Pubmed #15528096 No free full text.

Abstract: Dopaminergic loss can be visualised using (123)I-FP-CIT single photon emission computed tomography (SPECT) in several disorders including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Most previous SPECT studies have adopted region of interest (ROI) methods for analysis, which are subjective and operator-dependent. The purpose of this study was to investigate differences in striatal binding of (123)I-FP-CIT SPECT using the automated technique of statistical parametric mapping (SPM99) in subjects with DLB, Alzheimer's disease (AD), PD and healthy age-matched controls. This involved spatial normalisation of each subject's image to a customised template, followed by smoothing and intensity normalisation of each image to its corresponding mean occipital count per voxel. Group differences were assessed using a two-sample t test. Applying a height threshold of P <or= 0.05 corrected, the SPM[t] maps showed a significant bilateral reduced uptake in caudate, anterior and posterior putamen in DLB and PD subjects compared to AD subjects and controls. Significant reduction in binding was also observed bilaterally in the caudate nucleus in AD compared to controls. Striatal binding was indistinguishable between patients with DLB and PD. To investigate the usefulness of SPM as a decision aid in the evaluation of visually rated normal and abnormal patterns of uptake, receiver operator characteristic (ROC) curve analysis was performed using data from single-subject SPMs. The areas under the ROC curves were greater than 0.92, demonstrating comparable discriminatory power with visual rating. The automated voxel-based approach is a viable alternative to the subjective and often time-consuming method of ROI and, in addition, may have the potential to differentiate between normal and abnormal patterns of uptake in a manner similar to visual inspection.

Firbank MJ, Colloby SJ, Burn DJ, McKeith IG, O'Brien JT. · Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK. · Neuroimage. · Pubmed #14568499 No free full text.

Abstract: Tc99 HMPAO SPECT and T1 weighted 3D MRI scans were acquired in cognitively intact subjects with Parkinson's disease (PD) (n = 31), and in PD subjects with dementia (PDD) (n = 34), healthy controls (n = 37), those with Alzheimer's disease (AD) (n = 32), and those with dementia with Lewy bodies (DLB) (n = 15). We used SPM99 to look for regions which showed a reduction in perfusion on SPECT not related to associated structural brain changes assessed by a MRI scan. The precuneus and inferior lateral parietal regions showed a perfusion deficit in Parkinson's disease with dementia, similar to the pattern observed in DLB. In comparison, AD showed a perfusion deficit in the midline parietal region, in a more anterior and inferior location than in PDD, involving the posterior cingulate as well as the precuneus. The perfusion deficits in PDD are similar those in DLB, and in a location associated with visual processing, and may be associated with the visuospatial perception deficits which are present in persons with DLB and PDD.

Kenny ER, Burton EJ, O'Brien JT. · Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Campus for Ageing and Vitality, Newcastle upon Tyne, UK. · Dement Geriatr Cogn Disord. · Pubmed #18781072 No free full text.

Abstract: AIMS: To investigate whether subjects with dementia with Lewy bodies (DLB), Alzheimer's disease (AD) and Parkinson's disease with dementia (PDD) have reduced entorhinal cortex (EC) volumes compared to controls and cognitively intact Parkinson's disease (PD) subjects. METHODS: Volumes of the EC were measured on magnetic resonance imaging (MRI) scans of 144 individuals (aged over 65 years): 20 with DLB, 26 with AD, 30 with PDD, 31 with PD and 37 normal age-matched controls. RESULTS: Total normalised EC volumes were significantly smaller in DLB, AD and PDD patients compared to controls, and in DLB and AD patients compared to PD patients (p < 0.001). The percentage volume reduction in EC volume in the dementia groups relative to controls was 19.9% in DLB, 21.9% in AD and 14.7% in PDD. CONCLUSIONS: MRI measurements of the EC have shown that volumes are smaller in dementia subjects compared to controls and patients with non-dementia disorders. Further research is required to recognise those at risk of dementia and to differentiate between the dementias.

Rowan E, McKeith IG, Saxby BK, O'Brien JT, Burn D, Mosimann U, Newby J, Daniel S, Sanders J, Wesnes K. · Institute for Ageing and Health, Newcastle General Hospital, Newcastle upon Tyne, UK. · Dement Geriatr Cogn Disord. · Pubmed #17192712 No free full text.

Abstract: BACKGROUND: We examined attention-enhancing effects of the cholinesterase inhibitor donepezil in Dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD) by means of open label study. METHODS: 22 DLBs and 23 PDDs were assessed over 20 weeks using the Cognitive Drug Research Computerized Attentional Tasks. We examined how much closer our patients moved towards being normal for their age by comparing them to a non-demented elderly control sample (n = 183, aged 71-75 years). RESULTS: Donepezil treatment improved power of attention, continuity of attention and reaction time variability. The deficit in responses was moved towards normal by 38 and 56% for power of attention and 22 and 10% for continuity of attention in PDD and DLB, respectively. CONCLUSIONS: Improvements in attention were found with donepezil in PDD and DLB.

Boddy F, Rowan EN, Lett D, O'Brien JT, McKeith IG, Burn DJ. · Institute for Ageing and Health, University of Newcastle, UK. · Int J Geriatr Psychiatry. · Pubmed #17096456 No free full text.

Abstract: OBJECTIVE: We compared subjective sleep quality and excessive daytime somnolence (EDS) in controls, Parkinson's disease with (PDD) and without dementia (PD), dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). We investigated whether sleep dysfunction and EDS associate with motor phenotype in PD, PDD and DLB. METHOD: Assessments included the Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). RESULTS: EDS was more frequent in PD, DLB and PDD patients than in AD. PDD, PD and DLB patients also had worse sleep quality when compared with AD and controls. Baseline postural instability-gait difficulty (PIGD) motor phenotype in PDD was associated with a higher ESS score and frequency of EDS, but this association was lost at two years. PSQI scores did not differ between PIGD dominant and non-dominant PD, PDD and DLB patients. CONCLUSION: EDS and poor sleep quality are greater in PD, PDD and DLB, compared with AD. The dissociation of EDS and motor phenotype suggests their pathophysiology is anatomically and/or temporally distinct.

Burton EJ, McKeith IG, Burn DJ, Firbank MJ, O'Brien JT. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, UK. · Am J Geriatr Psychiatry. · Pubmed #17001024 No free full text.

Abstract: OBJECTIVE: The objective of this study was to investigate cross-sectional and longitudinal white matter hyperintensity (WMH) changes in older subjects with clinically diagnosed dementia. METHODS: Fluid-attenuated inversion recovery images were acquired one year apart in subjects with dementia with Lewy bodies (DLB), Parkinson disease dementia (PDD), Alzheimer disease (AD), and also healthy elderly comparison subjects. WMH volume was quantified using an automated technique. RESULTS: Baseline WMH (as a percent of brain volume) was significantly greater compared with healthy subjects (N=33, geometric mean WMH: 0.4%) in subjects with AD (N=23 [1.3%], analysis of variance post hoc p <0.001) but not PDD (N=13 [0.6%]) or DLB (N=14 [0.4%]). Increase in WMH volume (as a percent of brain volume) was not significantly different (Kruskal-Wallis p=0.4) between groups (AD median change: 0.08%; DLB: 0.025%; PDD: 0.07%, healthy: 0.02%). Severity of baseline WMH, rather than diagnosis or severity of dementia, was a significant predictor of lesion progression. Rate of change of WMH had no association with change in global cognitive performance. CONCLUSIONS: Significant WMH progression occurs in degenerative dementias with rates influenced by severity of lesions at baseline rather than dementia type or cognitive decline.

Colloby SJ, Pakrasi S, Firbank MJ, Perry EK, Piggott MA, Owens J, Wyper DJ, McKeith IG, Burn DJ, Williams ED, O'Brien JT. · Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK. · Neuroimage. · Pubmed #16959499 No free full text.

Abstract: INTRODUCTION: Alterations in cholinergic function have been reported to be associated with dementia. The aim of this study was to investigate differences in the distribution of muscarinic acetylcholine receptors (mAChRs) using (R,R) 123I-iodo-quinuclidinyl-benzilate (QNB) and single photon emission computed tomography (SPECT) in dementia with Lewy bodies (DLB), Parkinson's disease dementia (PDD) and age-matched controls. 123I-QNB binding was also compared to the corresponding cerebral perfusion changes in the same subjects. METHODS: 63 subjects (24 controls, 14 DLB, 25 PDD) underwent 123I-QNB and perfusion 99mTc-exametazine SPECT scanning. Image analysis, using statistical parametric mapping (SPM99), involved spatial normalisation of each image to a customised template, followed by smoothing and intensity normalisation of each image to its corresponding mean whole brain uptake. Group effects and correlations were assessed using two sample t tests and linear regression respectively. RESULTS: Relative to controls, significant elevation of 123I-QNB binding was apparent in the right occipital lobe in DLB and right and left occipital lobes in PDD (height threshold p<or=0.001 uncorrected). PDD also showed significant loss in uptake in frontal regions and temporal lobes bilaterally that was not present in DLB. These patterns appeared to be independent of any corresponding rCBF changes. CONCLUSION: Significant elevation of mAChRs in the occipital lobe was associated with DLB and PDD. This may relate to the visual disturbances that are prevalent in these disorders. Further studies are required in order to establish the role of mAChRs in visual function.

Burn DJ, Rowan EN, Allan LM, Molloy S, O'Brien JT, McKeith IG. · Institute for Ageing and Health, University of Newcastle, Newcastle upon Tyne, NE4 6BE, UK. · J Neurol Neurosurg Psychiatry. · Pubmed #16614017 links to  free full text

Abstract: BACKGROUND: A previous cross sectional study found over-representation of a postural instability gait difficulty (PIGD) motor subtype in Parkinson's disease patients with dementia (PDD) and dementia with Lewy bodies (DLB), compared with Parkinson's disease (PD). AIMS: (1) To examine rates of cognitive and motor decline over two years in PD (n=40), PDD (n=42) and DLB (n=41) subjects, compared with age matched controls (n=41), (2) to record whether motor phenotypes of PD, PDD, and DLB subjects changed during the study, (3) to find out if cognitive and motor decline in PD was associated with baseline motor subtype, and (4) to report the incidence of dementia in PD patients in relation to baseline motor subtype. RESULTS: Most of PDD and DLB participants were PIGD subtype at baseline assessment. In the non-demented PD group, tremor dominant (TD) and PIGD subtypes were more evenly represented. Cognitive decline over two years was greater in PDD and DLB groups (mean decline in MMSE -4.5 and -3.9, respectively), compared with PD (-0.2) and controls (-0.3). There was an association between PIGD subtype and increased rate of cognitive decline within the PD group. Of 40 PD patients, 25% of the 16 PIGD subtype developed dementia over two years, compared with none of the 18 TD or six indeterminate phenotype cases (chi2=6.7, Fisher's exact test p<0.05). CONCLUSION: A PIGD motor subtype is associated with a faster rate of cognitive decline in PD and may be considered a risk factor for incident dementia in PD.

Mosimann UP, Rowan EN, Partington CE, Collerton D, Littlewood E, O'Brien JT, Burn DJ, McKeith IG. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, United Kingdom. · Am J Geriatr Psychiatry. · Pubmed #16473980 No free full text.

Abstract: OBJECTIVE: Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB) have overlapping clinical and pathologic features. Recurrent visual hallucinations (RVH) are common in both disorders. The authors have compared details of hallucination characteristics and associated neuropsychiatric features in DLB and PDD. METHODS: This is a descriptive, cross-sectional study using the Institute of Psychiatry Visual Hallucinations Interview (IP-VHI) to explore self-reported frequency, duration, and phenomenology of RVH in PDD and DLB. The caregivers' ratings of hallucinations and other neuropsychiatric features were elicited with the Neuropsychiatric Inventory (NPI). RESULTS: Fifty-six patients (35 PDD; 21 DLB) with RVH were assessed. Hallucination characteristics were similar in both disorders. Simple hallucinations were rare. Most patients experienced complex hallucinations daily, normally lasting minutes. They commonly saw people or animals and the experiences were usually perceived as unpleasant. NPI anxiety scores were higher in PDD. Neuropsychiatric symptoms coexisting with hallucinations were apathy, sleep disturbance, and anxiety. CONCLUSIONS: Patients with mild to moderate dementia can provide detailed information about their hallucinations. Characteristics of RVH were similar in PDD and DLB, and phenomenology suggests the involvement of dorsal and ventral visual pathways in their generation. The coexistence of RVH with anxiety, apathy, and sleep disturbance is likely to impair patients' quality of life and may have treatment implications.

Firbank MJ, Molloy S, McKeith IG, Burn DJ, O'Brien JT. · Institute for Ageing and Health, University of Newcastle upon Tyne, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, NE4 6BE, UK. · J Neurol Neurosurg Psychiatry. · Pubmed #16170094 links to  free full text

Abstract: BACKGROUND: Brain perfusion deficits have been reported previously in subjects with Parkinson's disease in comparison with healthy controls. OBJECTIVE: To carry out a longitudinal study of perfusion in patients with Parkinson's disease and controls to find areas showing a reduction in perfusion over one year. METHODS: Two HMPAO cerebral perfusion scans were acquired one year apart in 30 subjects with Parkinson's disease (mean (SD) age, 76 (5) years) and 34 healthy comparison subjects (76 (7) years). Scans were normalised to the mean intensity in the cerebellum. RESULTS: Using SPM99 within groups to investigate regions that showed a decrease in perfusion between scans, it was found that in Parkinson's disease subjects but not controls there was a significant cluster in the frontal lobe (Brodmann area 10) where perfusion decreased over the year. CONCLUSIONS: The progressive frontal perfusion deficits in Parkinson's disease are consistent with results from previous structural and neuropsychological studies suggesting frontal lobe involvement and executive dysfunction even in early Parkinson's disease.

Burton EJ, McKeith IG, Burn DJ, O'Brien JT. · Institute for Ageing and Health, University of Newcastle upon Tyne, Newcastle upon Tyne, UK. · Mov Disord. · Pubmed #16116613 No free full text.

Abstract: Increased rates of brain atrophy are seen in Alzheimer's disease, but whether rates are similarly increased in other dementias such as Parkinson's disease dementia (PDD) has not been well examined. We determined the rates of brain atrophy using serial magnetic resonance imaging (MRI) in PDD and compared this finding to rates seen in cognitively intact Parkinson's disease (PD) patients and age-matched control subjects. Thirty-one patients (PD = 18, PDD = 13) and 24 age-matched controls underwent serial volumetric 1.5 T MRI scans, approximately 1 year apart. Baseline and repeat scans were registered and quantification of the brain boundary shift integral was used to determine whole-brain atrophy rates. Rates of brain atrophy were significantly increased in PDD (1.12 +/- 0.98%/year) compared to PD (0.31 +/- 0.69%/year; P = 0.018) and control subjects (0.34 +/- 0.76%/year; P = 0.015). There were no differences in atrophy rates between controls and PD (P = 0.79). No correlations between increased atrophy rates and age or dementia severity (Mini-Mental State Examination score) were observed. Serial MRI may be a useful tool for monitoring disease progression in PDD and further studies should investigate its utility for early diagnosis.

Firbank MJ, Burn DJ, McKeith IG, O'Brien JT. · The Institute for Ageing and Health, University of Newcastle upon Tyne, UK. · Int J Geriatr Psychiatry. · Pubmed #16035122 No free full text.

Abstract: BACKGROUND: People with Parkinson's disease (PD) have an increased risk of developing dementia (PDD), which often has clinical features similar to dementia with Lewy bodies (DLB). Whilst perfusion studies have shown parieto-occipital hypoperfusion in DLB and PDD relative to controls, there have not been any longitudinal studies of perfusion changes in PDD and DLB. METHODS: In this study, we measured brain perfusion using Tc99m HMPAO SPECT over one year in 17 PDD, 18 DLB and 34 healthy subjects. We used SPM99 to compare perfusion changes in the two dementia groups against the control group. RESULTS: We did not see any reductions in perfusion in either of the dementia groups. However, in the DLB, but not PDD group, there was a significant increase in putamen perfusion relative to controls over the year. In both DLB and PDD groups, there was a correlation between striatal perfusion increase over the year, and worsening of parkinsonism. Perfusion changes were not secondary to changes in antiparkinsonian medication. CONCLUSION: The increase in striatal perfusion may be a compensatory change related to decreasing striatal dopaminergic input from the substantia nigra in PDD and DLB, consistent with the increased predominance of rigidity over tremor symptoms in these groups compared with non-demented PD.

Colloby SJ, Williams ED, Burn DJ, Lloyd JJ, McKeith IG, O'Brien JT. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle University, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK. · Eur J Nucl Med Mol Imaging. · Pubmed #15931516 No free full text.

Abstract: PURPOSE: The objective of this study was to investigate the rate of progression of nigrostriatal dopaminergic loss in subjects with dementia with Lewy bodies (DLB), Parkinson's disease (PD) and PD with dementia (PDD) using serial 123I-FP-CIT SPECT imaging. We hypothesised that striatal rates of decline in patients would be greater than in controls, and that DLB and PDD would show similar rates, reflecting the similarity in neurobiological mechanisms of dopaminergic loss between the two disorders. METHODS: We studied 20 patients with DLB, 20 with PD, 15 with PDD and 22 healthy age-matched controls. Semi-automated region of interest (ROI) analysis was performed on both baseline and repeat scans for each subject and mean striatal uptake ratios (caudate, anterior and posterior putamen) were calculated. RESULTS: Rates of decline in striatal binding between groups were assessed using ANCOVA. Significant differences between patients and controls were observed in caudate (DLB, PD, PDD, p< or =0.01), anterior putamen (DLB, PDD, p< or =0.05; PD, p=0.07) and posterior putamen (DLB, PD, PDD, p<0.006). Rates of decline were similar between DLB, PD and PDD. CONCLUSION: In conclusion, this is the first study to show that significant progressive dopaminergic loss occurs in DLB and PDD using serial 123I-FP-CIT SPECT. Dementia severity and motor impairment were correlated with decline, suggesting that dopaminergic loss may play an important role in cognitive as well as motor features.

Aarsland D, Perry R, Larsen JP, McKeith IG, O'Brien JT, Perry EK, Burn D, Ballard CG. · Section of Geriatric Psychiatry, Central Hospital, Rogaland, Stavanger, Norway. · J Clin Psychiatry. · Pubmed #15889951 No free full text.

Abstract: BACKGROUND: Severe sensitivity to neuroleptic agents is a major clinical problem in dementia with Lewy bodies (DLB), but has not been determined in Parkinson's disease (PD) and PD with dementia (PDD). METHOD: Severe neuroleptic sensitivity reactions (NSRs) were evaluated according to an operationalized definition blind to clinical and neuropathologic diagnoses in prospectively studied patients exposed to neuroleptics from 2 centers. The study was conducted from June 1995 to May 2003. RESULTS: Ninety-four patients were included (15 with DLB, 36 with PDD, 26 with PD, 17 with Alzheimer's disease, all diagnosed with various operational criteria). Severe NSR only occurred in patients with Lewy body disease: DLB (8 [53%]), PDD (14 [39%]), and PD (7 [27%]), but did not occur in Alzheimer's disease (p = .006). Severe NSR was not associated with other clinical or demographic features. In DLB, severe NSR was not associated with neuropathologic indices (Consortium to Establish a Registry for Alzheimer's Disease staging, Braak staging, or cortical distribution of Lewy bodies). CONCLUSIONS: An operationalized evaluation of severe NSR blind to diagnosis confirmed the high prevalence in DLB and identified high frequencies in Parkinson's disease and PDD with important implications for clinical practice.

Mosimann UP, Müri RM, Burn DJ, Felblinger J, O'Brien JT, McKeith IG. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, UK. · Brain. · Pubmed #15774501 links to  free full text

Abstract: Neurodegeneration in Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB) affect cortical and subcortical networks involved in saccade generation. We therefore expected impairments in saccade performance in both disorders. In order to improve the pathophysiological understanding and to investigate the usefulness of saccades for differential diagnosis, saccades were tested in age- and education-matched patients with PDD (n = 20) and DLB (n = 20), Alzheimer's disease (n = 22) and Parkinson's disease (n = 24), and controls (n = 24). Reflexive (gap, overlap) and complex saccades (prediction, decision and antisaccade) were tested with electro-oculography. PDD and DLB patients had similar impairment in all tasks (P > 0.05, not significant). Compared with controls, they were impaired in both reflexive saccade execution (gap and overlap latencies, P < 0.0001; gains, P < 0.004) and complex saccade performance (target prediction, P < 0.0001; error decisions, P < 0.003; error antisaccades: P < 0.0001). Patients with Alzheimer's disease were only impaired in complex saccade performance (Alzheimer's disease versus controls, target prediction P < 0.001, error decisions P < 0.0001, error antisaccades P < 0.0001), but not reflexive saccade execution (for all, P > 0.05). Patients with Parkinson's disease had, compared with controls, similar complex saccade performance (for all, P > 0.05) and only minimal impairment in reflexive tasks, i.e. hypometric gain in the gap task (P = 0.04). Impaired saccade execution in reflexive tasks allowed discrimination between DLB versus Alzheimer's disease (sensitivity > or =60%, specificity > or =77%) and between PDD versus Parkinson's disease (sensitivity > or =60%, specificity > or =88%) when +/-1.5 standard deviations was used for group discrimination. We conclude that impairments in reflexive saccades may be helpful for differential diagnosis and are minimal when either cortical (Alzheimer's disease) or nigrostriatal neurodegeneration (Parkinson's disease) exists solely; however, they become prominent with combined cortical and subcortical neurodegeneration in PDD and DLB. The similarities in saccade performance in PDD and DLB underline the overlap between these conditions and underscore differences from Alzheimer's disease and Parkinson's disease.

Tam CW, Burton EJ, McKeith IG, Burn DJ, O'Brien JT. · Department of Psychiatry, Tai Po Hospital, Hong Kong. · Neurology. · Pubmed #15753423 No free full text.

Abstract: OBJECTIVE: To investigate the extent of medial temporal lobe atrophy (MTA) on MRI in Parkinson disease (PD) with and without dementia compared with Alzheimer disease (AD) and dementia with Lewy bodies (DLB) and to determine whether MTA correlates with cognitive impairment in PD and PD dementia (PDD). METHODS: Coronal T1-weighted MRI scans were acquired from control subjects (n = 39) and patients with PD (n = 33), PDD (n = 31), DLB (n = 25), and AD (n = 31), diagnosed according to standardized clinical diagnostic criteria. Cognitive function was assessed using the Cambridge Cognitive Examination (CAMCOG), and MTA was rated visually using a standardized (Scheltens) scale. RESULTS: More severe MTA was seen in PDD (p = 0.007), DLB (p < 0.001), and AD (p < 0.001) vs control subjects. PD subjects had greater hippocampal atrophy than control subjects (p = 0.015) but less than subjects with DLB and AD, though not with PDD. MTA correlated with CAMCOG score and memory scores in the DLB group and with age in control, PDD, and AD groups. There were no correlations between MTA and cognitive impairment in PD, PDD, and AD. PDD and DLB had a similar profile of cognitive impairment and MTA. CONCLUSIONS: Medial temporal lobe atrophy (MTA) was seen in cognitively intact older subjects with Parkinson disease (PD) and was not more pronounced in Parkinson disease dementia (PDD). Alzheimer disease (AD) and, to a lesser extent, dementia with Lewy bodies (DLB) showed more pronounced MTA. Results suggest early hippocampal involvement in PD and that when dementia develops in PD, anatomic structures apart from the hippocampus are predominantly implicated. Greater hippocampal involvement in AD vs PDD and DLB is consistent with clinical, cognitive, and pathologic differences between the disorders.

Mosimann UP, Mather G, Wesnes KA, O'Brien JT, Burn DJ, McKeith IG. · Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne NE4 6BE, UK. · Neurology. · Pubmed #15596755 No free full text.

Abstract: OBJECTIVE: To quantify visual discrimination, space-motion, and object-form perception in patients with Parkinson disease dementia (PDD), dementia with Lewy bodies (DLB), and Alzheimer disease (AD). METHODS: The authors used a cross-sectional study to compare three demented groups matched for overall dementia severity (PDD: n = 24; DLB: n = 20; AD: n = 23) and two age-, sex-, and education-matched control groups (PD: n = 24, normal controls [NC]: n = 25). RESULTS: Visual perception was globally more impaired in PDD than in nondemented controls (NC, PD), but was not different from DLB. Compared to AD, PDD patients tended to perform worse in all perceptual scores. Visual perception of patients with PDD/DLB and visual hallucinations was significantly worse than in patients without hallucinations. CONCLUSIONS: Parkinson disease dementia (PDD) is associated with profound visuoperceptual impairments similar to dementia with Lewy bodies (DLB) but different from Alzheimer disease. These findings are consistent with previous neuroimaging studies reporting hypoactivity in cortical areas involved in visual processing in PDD and DLB.

O'Brien JT, Colloby S, Fenwick J, Williams ED, Firbank M, Burn D, Aarsland D, McKeith IG. · Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Newcastle upon Tyne, England. j.t.o' · Arch Neurol. · Pubmed #15210531 links to  free full text

Abstract: BACKGROUND: Dementia with Lewy bodies (DLB) is a common form of late-life dementia that can be difficult to differentiate from other disorders, especially Alzheimer disease (AD), during life. At autopsy the striatal dopaminergic transporter is reduced. OBJECTIVES: To examine the extent and pattern of dopamine transporter loss using iodine I 123-radiolabeled 2beta-carbomethoxy-3beta-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (FP-CIT) with single-photon emission computed tomography (SPECT) in DLBs compared with other dementias and to assess its potential to enhance a differential diagnosis. DESIGN: Cohort study comparing FP-CIT with criterion standard of consensus clinical diagnosis. SETTING: General hospital. PARTICIPANTS: One hundred sixty-four older subjects (33 healthy older control subjects, 34 with NINCDS/ADRDA [National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association]-confirmed AD, 23 with consensus guideline-confirmed DLB, 38 with United Kingdom's Parkinson Disease Society Brain Bank-confirmed Parkinson disease [PD], and 36 with PD and dementia). INTERVENTIONS: Injection of (123)I-2beta-carbomethoxy-3beta-(4-iodophenyl)-N-(3-fluoropropyl) nortropane with SPECT scan performed at 4 hours. MAIN OUTCOME MEASURES: Visual ratings of scans and region of interest analysis. RESULTS: Significant reductions (P<.001) in FP-CIT binding occurred in the caudate and anterior and posterior putamens in subjects with DLB compared with subjects with AD and controls. Transporter loss in DLBs was of similar magnitude to that seen in PD, but with a flatter rostrocaudal (caudate-putamen) gradient (P =.001), while the greatest loss in all 3 areas was seen in those who had PD and dementia. Both region of interest analysis and visual ratings provided good separation between DLBs and AD (region of interest: sensitivity, 78%; specificity, 94%; positive predictive value, 90%) but not among subjects with DLB, PD, and PD with dementia. CONCLUSIONS: Dopamine transporter loss can be detected in vivo using FP-CIT SPECT in DLB. Further studies, especially of subjects with DLB without PD, are required to fully establish use in clinical practice.