Department of Psychiatry, Yamagata University School of Medicine, Yamagata, Japan.
Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Psychogeriatrics. 2024 Jul;24(4):1004-1022. doi: 10.1111/psyg.13147. Epub 2024 Jun 4.
Research criteria for the diagnosis of prodromal dementia with Lewy bodies (DLB) include three clinical subtypes: mild cognitive impairment with Lewy bodies (MCI-LB), delirium-onset prodromal DLB, and psychiatric-onset prodromal DLB. Late-onset psychiatric manifestations are at a higher risk of developing dementia, but its relation to prodromal DLB remains unclear. In addition to the risk of severe antipsychotic hypersensitivity reactions, accurate discrimination from non-DLB cases is important due to the potential differences in management and prognosis. This article aims to review a rapidly evolving psychiatric topic and outline clinical pictures of psychiatric-onset prodromal DLB, including the proposed biomarker findings of MCI-LB: polysomnography-confirmed rapid eye movement sleep behaviour disorder, cardiac [I]metaiodobenzylguanidine scintigraphy, and striatal dopamine transporter imaging. We first reviewed clinical pictures of patients with autopsy-confirmed DLB. Regarding clinical reports, we focused on the patients who predominantly presented with psychiatric manifestations and subsequently developed DLB. Thereafter, we reviewed clinical studies regarding the diagnostic applications of the proposed biomarkers to patients with late-onset psychiatric disorders. Clinical presentations were mainly late-onset depression and psychosis; however, other clinical manifestations were also reported. Psychotropic medications before a DLB diagnosis may cause extrapyramidal signs, and potentially influences the proposed biomarker findings. These risks complicate clinical manifestation interpretation during the management of psychiatric symptoms. Longitudinal follow-up studies with standardised evaluations until conversion to DLB are needed to investigate the temporal trajectories of core features and proposed biomarker findings. In patients with late-onset psychiatric disorders, identification of patients with psychiatric-onset prodromal DLB provides the opportunity to better understanding the distinct prognostic subgroup that is at great risk of incident dementia. Advances in the establishment of direct biomarkers for the detection of pathological α-synuclein may encourage reorganising the phenotypic variability of prodromal DLB.
诊断路易体痴呆（DLB）前驱期的研究标准包括三种临床亚型：路易体轻度认知障碍（MCI-LB）、谵妄起病前驱期 DLB 和精神病起病前驱期 DLB。迟发性精神病表现发生痴呆的风险较高，但与前驱期 DLB 的关系尚不清楚。除了发生严重抗精神病药物过敏反应的风险外，由于管理和预后可能存在差异，因此准确区分非 DLB 病例非常重要。本文旨在综述一个快速发展的精神科课题，并概述精神病起病前驱期 DLB 的临床特征，包括 MCI-LB 的拟议生物标志物发现：多导睡眠图证实的快速眼动睡眠行为障碍、心脏[I]间碘苄胍闪烁扫描和纹状体多巴胺转运蛋白成像。我们首先回顾了经尸检证实的 DLB 患者的临床特征。关于临床报告，我们主要关注以精神病表现为主并随后发展为 DLB 的患者。之后，我们回顾了关于拟议生物标志物在迟发性精神障碍患者中的诊断应用的临床研究。临床表现主要为迟发性抑郁症和精神病；然而，也有其他临床表现的报道。DLB 诊断前的精神药物治疗可能导致锥体外系症状，并可能影响拟议的生物标志物发现。这些风险使在管理精神症状期间对临床表现的解释复杂化。需要进行具有标准评估的纵向随访研究，直到转换为 DLB，以研究核心特征和拟议生物标志物发现的时间轨迹。在迟发性精神障碍患者中，识别精神病起病前驱期 DLB 患者为了解具有较大痴呆风险的独特预后亚组提供了机会。用于检测病理性α-突触核蛋白的直接生物标志物的建立进展可能会鼓励对前驱期 DLB 的表型变异性进行重新组织。
