Lewy bodies and dementia

The discovery of widely distributed Lewy bodies (LBs) in the brains of patients with dementia has stimulated much clinical and pathologic inquiry. This clinico-pathologic syndrome is now referred to as dementia with Lewy bodies (DLB). Diagnostic criteria for DLB proposed at a workshop in 1995 are receiving detailed scrutiny. The criteria are complex to apply, and appear to have high specificity, but variable sensitivity. Neuropathologic studies have been aided by the development of probes against a-synuclein, a key component of LBs. Widespread LBs in limbic or cortical areas contribute to dementia. Pharmacologic management of cognitive and behavioral symptoms in patients with DLB is being explored. There is evidence that cholinesterase inhibitors may have beneficial effects.     

Neuronal RNA oxidation is a prominent feature of dementia with Lewy bodies

An approach was used to identify the oxidized nucleoside, 8-hydroxyguanosine in brains of dementia with Lewy bodies. Neurons with marked immunoreaction of 8-hydroxyguanosine in the cytoplasm were widely distributed in the hippocampal region and temporal neocortex. Relative intensity measurements of neuronal 8-hydroxyguanosine immunoreactivity showed that there was a significant increase in nucleic acid oxidation in dementia with Lewy bodies compared with controls. Treatment with nuclease (DNase or RNase) before the immunostaining demonstrated that RNA was a major site of nucleic acid oxidation. Together with the previously reported RNA oxidation in vulnerable neurons in Alzheimer and Parkinson diseases, neuronal RNA oxidation in dementia with Lewy bodies might represent one of the fundamental abnormalities in age-associated neurodegenerative diseases.     

Basal forebrain atrophy is a distinctive pattern in dementia with Lewy bodies

We determined brain atrophy patterns in dementia with Lewy bodies and Alzheimer's disease using voxel-based morphometry, an indirect volumetry. Ten patients with dementia with Lewy bodies, 10 patients with Alzheimer's disease and 10 controls were included. All groups were matched for age; sex and global differences in voxel intensities were included as confounding covariates. We observed basal forebrain atrophy discriminating dementia with Lewy bodies from Alzheimer's disease. Compared to controls, atrophy of lateral prefrontal cortex and left premotor cortex was seen in dementia with Lewy bodies whereas atrophy of the medial temporal cortex, posterior parietal cortex, thalamus and temporo-occipital areas was observed in Alzheimer's disease. Atrophy of insular cortex was found in both patient groups.     

Treatment of dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is known for its partial resistance and hypersensitivity to some treatments, but DLB is treatable with cholinesterase inhibitors, sometimes better than in Alzheimer's disease. Cholinesterase inhibitors have a symptomatic effect on cognition and behavior. Nevertheless, new antipsychotics are sometimes also useful to manage psychotic symptoms. Although DLB patients respond less well to levodopa than patients with Parkinson's disease, 75 percent of DLB patients improve with levodopa, which is the best-tolerated dopaminergic agent. Nonpharmacological strategies include speech therapy, physiotherapy, psychotherapy, and educational support groups for care givers.     

Neuroimaging of dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is a relative newcomer to the field of late-life dementia. Although a diversity of imaging methodologies is now available for the study of dementia, these have been applied most often to Alzheimer's disease (AD). Studies on DLB, although fewer, have yielded fascinating and important insights into the underlying pathophysiology of this condition and allowed clinical differentiation of DLB from other dementias. Imaging research on DLB has had significant ramifications in terms of raising the profile of DLB and helping define it as a distinctive and separate disease entity from AD.     

Microbleeds in dementia with Lewy bodies

Journal of Neurology - Microbleeds are associated with the development of dementia in older people and are common in Alzheimer’s disease (AD). Their prevalence and clinical importance in...     

载脂蛋白E基因多态性与路易体痴呆关系的Meta分析

目的 探讨载脂蛋白E（APOE）基因多态性与路易体痴呆（DLB）的相关性。方法 检索PubMed、EMBASE、Cochrane图书馆以及CNKI数据库截止至2018年4月发表的相关文献,确定文献纳入和排除标准,并采用Newcastle-Ottawa（NOS）进行文献质量评估,提取高质量文献的有用部分,应用RevMan 5.3软件进行统计分析。结果 共纳入21篇文献,包括DLB患者1 178例,健康对照6 272例,Meta分析结果显示APOE ε4是DLB的危险因素,其中ε4 vs.ε3（OR=2.51,95%CI：1.87~3.38,P<0.001）、ε4 vs.ε2（OR=2.71,95%CI：1.73~4.26,P=0.007）,APOE ε2与DLB无显著相关性（P>0.05）。在高加索人群的亚组分析中,也得出一致结果。结论 APOE基因多态性与DLB具有相关性,APOE ε4是DLB发病的危险因素,APOE ε2与DLB易感性无明显相关性。     

载脂蛋白E基因多态性与路易体痴呆关系的Meta分析

目的探讨载脂蛋白E (APOE)基因多态性与路易体痴呆(DLB)的相关性。方法检索PubMed、EMBASE、Cochrane图书馆以及CNKI数据库截止至2018年4月发表的相关文献,确定文献纳入和排除标准,并采用Newcastle-Ottawa(NOS)进行文献质量评估,提取高质量文献的有用部分,应用Rev Man 5.3软件进行统计分析。结果共纳入21篇文献,包括DLB患者1 178例,健康对照6 272例,Meta分析结果显示APOEε4是DLB的危险因素,其中ε4 vs.ε3 (OR=2.51,95%CI:1.87～3.38,P 0.001)、ε4 vs.ε2 (OR=2.71,95%CI:1.73～4.26,P=0.007),APOEε2与DLB无显著相关性(P 0.05)。在高加索人群的亚组分析中,也得出一致结果。结论 APOE基因多态性与DLB具有相关性,APOEε4是DLB发病的危险因素,APOEε2与DLB易感性无明显相关性。     

Biomarkers: Parkinson disease with dementia and dementia with Lewy bodies

Dementia is a common feature in Parkinson disease (PD), the time of onset determining how patients are classified. Those patients where dementia develops prior to parkinsonism or during the first year of disease are designated as having dementia with Lewy bodies (DLB). In those where dementia develops over a year after the onset of motor signs, the condition is known as Parkinson's disease with dementia (PDD).While this seems at first sight to be a definitive way to distinguish these conditions, reality is rather different. The overlap between them is considerable, and there is much uncertainty associated with patients who have both motor symptoms and early cognitive impairment. The diagnosis is still based on medical history and clinical evaluation. It is not even certain that they can be accurately distinguished at autopsy. For this reason, the data concerning these entities have been reviewed, to examine various markers employed or measured in clinical, neuropathological, neuroimaging, and biochemical investigations. The concept of PDD and DLB being separate conditions is comparatively new, and the most promising tools with which to separate them at present are cerebrospinal fluid (CSF) markers and positron emission tomography (PET) scanning that indicate increased amyloid-β burden in DLB compared to PDD. However as yet there are no markers that unequivocally distinguish between PDD and DLB.     

Relationship between Parkinson disease with dementia and dementia with Lewy bodies

Parkinson disease (PD) and dementia with Lewy bodies (DLB) are considered Lewy body diseases (LBDs). To clarify the relation between PD with dementia (PDD) and DLB, 30 patients with LBD were divided into pathological subtypes according to the consensus guidelines for DLB. Patients with PDD showed neocortical and limbic type of LBD as well as patients with DLB. Dementia had not been noted in 2 patients with neocortical type. Our results indicate that PDD and DLB share a common pathological substrate and that the pathological subtypes of LBD show considerable overlap in clinical manifestations.     

路易体痴呆1例报道

路易体痴呆(dementia with Lewy bodies, DLB)是老年性痴呆的常见原因,临床上以波动性的认知功能损害,视幻觉为主的精神症状以及帕金森样运动障碍为主要表现,在临床工作中很容易被误诊.现将本院收治的1例报道如下.     

Visuoperceptual impairment in dementia with Lewy bodies

BACKGROUND: In dementia with Lewy bodies (DLB), vision-related cognitive and behavioral symptoms are common, and involvement of the occipital visual cortices has been demonstrated in functional neuroimaging studies. OBJECTIVES: To delineate visuoperceptual disturbance in patients with DLB in comparison with that in patients with Alzheimer disease and to explore the relationship between visuoperceptual disturbance and the vision-related cognitive and behavioral symptoms. DESIGN: Case-control study. SETTING: Research-oriented hospital. PATIENTS: Twenty-four patients with probable DLB (based on criteria of the Consortium on DLB International Workshop) and 48 patients with probable Alzheimer disease (based on criteria of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association) who were matched to those with DLB 2:1 by age, sex, education, and Mini-Mental State Examination score. MAIN OUTCOME MEASURES: Four test items to examine visuoperceptual functions, including the object size discrimination, form discrimination, overlapping figure identification, and visual counting tasks. RESULTS: Compared with patients with probable Alzheimer disease, patients with probable DLB scored significantly lower on all the visuoperceptive tasks (P<.04 to P<.001). In the DLB group, patients with visual hallucinations (n = 18) scored significantly lower on the overlapping figure identification (P = .01) than those without them (n = 6), and patients with television misidentifications (n = 5) scored significantly lower on the size discrimination (P<.001), form discrimination (P = .01), and visual counting (P = .007) than those without them (n = 19). CONCLUSIONS: Visual perception is defective in probable DLB. The defective visual perception plays a role in development of visual hallucinations, delusional misidentifications, visual agnosias, and visuoconstructive disability charcteristic of DLB.