Background: Younger-onset dementia (YOD) can be challenging to diagnose due to its younger age of onset, heterogeneous aetiologies and broad range of presentations. Misdiagnosis is common with psychiatric conditions often diagnosed initially and diagnostic delay of five years is common. More information is needed to better understand and diagnose YOD, including the nature of symptom onset, progression of the disease, the relationship between cognition and functional outcomes for patients and carers, imaging changes and novel biomarkers. This paper reports on the background behind the Investigating the clinical utility of biomarkers and other novel tests in younger-onset neurocognitive disorders, the BeYOND study, and its methodology. Methods: BeYOND is a clinically-oriented real-world longitudinal study that follows younger people presenting with an onset of neuropsychiatric symptoms at 65 years or less. We aim to collect information on participants' cognition, neuroimaging, mental health, and blood and cerebrospinal fluid (CSF) biomarkers at 18-month time-points over 3 years. We also aim to collect information regarding the experience of carers and/or family of participants. Conclusion: Serial assessment of symptomatology, cognition, imaging, and blood and CSF biomarkers will be correlated with eventual diagnosis to determine the usefulness of these measures in determining a confident diagnosis. In addition, repeat measurements of the mental health and well-being of the participant and that of their carers/family while they traverse their diagnostic journey will provide important information about service provision and how they can be better supported.

中文翻译：

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研究生物标志物和其他新测试在年轻神经认知障碍中的临床效用：BeYOND 研究，真实世界环境中纵向临床研究的协议。

背景：年轻型痴呆 (YOD) 由于其发病年龄较小、病因异质和表现范围广泛而难以诊断。误诊常见于精神疾病，通常最初被诊断出来，并且诊断延迟五年是常见的。需要更多信息来更好地理解和诊断 YOD，包括症状发作的性质、疾病的进展、患者和护理人员的认知与功能结果之间的关系、影像学变化和新的生物标志物。本文报告了研究生物标志物和其他新测试在年轻神经认知障碍中的临床效用、BeYOND 研究及其方法背后的背景。方法：BeYOND 是一项以临床为导向的现实世界纵向研究，追踪在 65 岁或以下出现神经精神症状的年轻人。我们的目标是在超过 3 年的 18 个月时间点收集参与者的认知、神经影像学、心理健康以及血液和脑脊液 (CSF) 生物标志物的信息。我们还旨在收集有关照顾者和/或参与者家属的经历的信息。结论：症状学、认知、影像学以及血液和脑脊液生物标志物的系列评估将与最终诊断相关联，以确定这些措施在确定可靠诊断中的有用性。此外，