Leroi, Iracema

Abstract Dementia with Lewy bodies (DLB), a progressive neurodegenerative disease with heterogeneous clinical presentations, greatly impacts patients, caregivers, and society. Despite its frequency, diagnosing and treating DLB remains challenging. Advances in in vivo biomarker assays reflecting underlying pathology are improving disease identification, diagnostic accuracy, and therapeutic development for biologically targeted, disease‐modifying agents. Consequently, definitions of Alzheimer's disease and Parkinson's disease (PD) have shifted to focus on pathological changes occurring before clinical features, with proposed frameworks for detecting pathological amyloid and tau, neurodegeneration, and other markers (National Institute on Aging‐Alzheimer's Association) and alpha‐synucleinopathy and dopaminergic degeneration (Neuronal α‐synuclein Disease Integrated Staging System, SynNeurGe). The biological frameworks, particularly those related to alpha‐synuclein (α‐synuclein), have sparked debate about unifying DLB and PD under a single pathobiologic disease. This paper discusses the implications of these biological frameworks for the DLB community, addressing topics regarding multiple pathologies and neurochemical systems, clinical heterogeneity, and functional impairment, and exploring the potential impact on clinical trials and care. Highlights DLB is a progressive neurodegenerative disease with varied clinical presentations. Diagnosing and treating DLB remains challenging despite its frequency. Biological frameworks are reshaping Alzheimer's and Parkinson's definitions. In vivo biomarkers are improving DLB identification and diagnostic accuracy. Debate exists regarding unifying DLB and Parkinson's under one pathobiology.

AbstractBackgroundNo specific clinical rating scale currently exists for Lewy body dementia (LBD). Clinical rating scales developed for other diseases are therefore used instead for LBD clinical trials. However, these scales are not optimized for LBD and may not sufficiently reflect the complex array of LBD‐related phenomenology, making it more difficult to interpret outcome data from LBD clinical trials.MethodA working group comprised of 14 members bridging various international LBD‐focused research groups was convened to develop the first iteration of the LBD‐DRS with a focus on inclusion of key LBD related symptom domains, ensuring that any scale is mapped to regulatory expectations, and an emphasis on being patient‐centered. This draft was then subsequently presented to a broader stakeholder group (»50 participants) at the International Lewy body Dementia Conference in June 2022 for further feedback, leading to a further iteration of the scale.ResultThe LBD‐DRS has been designed to capture ratings of the frequency and severity of symptoms across the key domains relevant to LBD – cognitive, neuropsychiatric, motor, autonomic and sleep – as well as the functional impact and perceived burden of symptoms for patients and their care partners. An international Delphi exercise is now planned with many LBD‐relevant stakeholders, which will be coupled with workgroup engagement (for example, with patient‐caregiver groups) to further develop the scale with the resulting final draft anticipated for pilot use in the near future.ConclusionsIn this presentation we will elaborate on the development of the scale, key areas that it will cover as well as challenge points and next steps. Upon completion of the development and refinement of the LBD‐DRS, we propose that this scale will have utility as valid and LBD specific outcome measure in LBD clinical trials.

Abstract Dementia with Lewy bodies (DLB) is clinically defined by the presence of visual hallucinations, fluctuations, rapid eye movement (REM) sleep behavioral disorder, and parkinsonism. Neuropathologically, it is characterized by the presence of Lewy pathology. However, neuropathological studies have demonstrated the high prevalence of coexistent Alzheimer's disease, TAR DNA‐binding protein 43 (TDP‐43), and cerebrovascular pathologic cases. Due to their high prevalence and clinical impact on DLB individuals, clinical trials should account for these co‐pathologies in their design and selection and the interpretation of biomarkers values and outcomes. Here we discuss the frequency of the different co‐pathologies in DLB and their cross‐sectional and longitudinal clinical impact. We then evaluate the utility and possible applications of disease‐specific and disease‐nonspecific biomarkers and how co‐pathologies can impact these biomarkers. We propose a framework for integrating multi‐modal biomarker fingerprints and step‐wise selection and assessment of DLB individuals for clinical trials, monitoring target engagement, and interpreting outcomes in the setting of co‐pathologies.