Anosognosia in dementia with Lewy bodies: a systematic review

ABSTRACT Background: Anosognosia, i.e. lack of awareness of one’s own symptoms, is a very common finding in patients with dementia and is related to neuropsychiatric symptoms and worse prognosis. Although dementia with Lewy bodies (DLB) is the second most common form of degenerative dementia, literature on anosognosia in this disease is scarce. Objectives: This paper aimed to review the current evidence on anosognosia in patients with DLB, including its prevalence in comparison with other neurological conditions, its severity and anatomical correlations. Methods: Database searches were performed in PubMed, Web of Knowledge and PsycINFO for articles assessing anosognosia in DLB. A total of 243 studies were retrieved, but only six were included in the review. Results: Potential risk of selection, comparison or outcome biases were detected in relation to all the studies selected. Most of the studies used self-report memory questionnaires to assess cognitive complaints and compared their results to scores from informant-based instruments or to participants’ cognitive performance in neuropsychological tasks. Subjects with DLB had worse awareness regarding memory than healthy older controls, but the results concerning differences in anosognosia between DLB and Alzheimer’s disease (AD) patients were inconsistent across studies. Presence of AD pathology and neuroimaging biomarkers appeared to increase the prevalence of anosognosia in individuals with DLB. Conclusion: Anosognosia is a common manifestation of DLB, but it is not clear how its prevalence and severity compare with AD. Co-existence of AD pathology seems to play a role in memory deficit awareness in DLB.摘要 背景：疾病感缺失（anosognosia，即对自身症状缺乏知晓）在痴呆患者中极为常见，且与神经精神症状及不良预后密切相关。路易体痴呆（Dementia with Lewy Bodies, DLB）是第二常见的变性性痴呆类型，但针对该疾病中疾病感缺失的相关研究文献仍较为匮乏。 研究目的：本文旨在综述当前关于路易体痴呆患者疾病感缺失的现有研究证据，包括其与其他神经系统疾病的患病率对比、严重程度及解剖学相关性。 研究方法：在PubMed、Web of Knowledge及PsycINFO数据库中检索评估路易体痴呆患者疾病感缺失的相关文献，共检索到243项研究，最终仅纳入6项进行本次综述。 研究结果：纳入的所有研究均存在潜在的选择偏倚、比较偏倚或结局偏倚风险。多数研究采用自我报告式记忆问卷评估认知主诉，并将所得结果与知情人评定工具的得分，或是受试者在神经心理学任务中的认知表现进行对比。路易体痴呆患者对自身记忆障碍的知晓程度较健康老年对照群体更差，但关于路易体痴呆与阿尔茨海默病（Alzheimer’s Disease, AD）患者疾病感缺失差异的研究结果在各研究间并不一致。合并阿尔茨海默病病理改变及神经影像学生物标志物似乎会升高路易体痴呆患者的疾病感缺失患病率。 研究结论：疾病感缺失是路易体痴呆的常见临床表现，但目前仍无法明确其患病率与严重程度与阿尔茨海默病相比存在何种差异。合并阿尔茨海默病病理改变似乎对路易体痴呆患者的记忆缺陷知晓情况存在一定影响。