Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, Connecticut, USA,
Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, Connecticut, USA,
Neuroepidemiology. 2020;54(2):180-184. doi: 10.1159/000502862. Epub 2020 Feb 5.
An issue of central importance for most neurological disorders is that of case definition. In the field of neuroepidemiology, case definition informs the design, conduct, and interpretation of research studies that range from observational to interventional studies, from case-control to cohort studies, and from descriptive to analytical studies. For essential tremor (ET), one of the most common neurological disorders, the issue of case definition is particularly important. Though traditionally viewed as a monochromatic disorder, recent years have seen an expansion of the clinical phenotype. In a recently proposed consensus statement on tremor, a proposal was made to separate from ET a new tentatively and uncertainly-defined entity characterized by the presence of additional neurological signs other than action tremor. This entity would be termed "ET-plus". The aims of this invited paper are to discuss the impact of the proposed nomenclature on studies of ET neuroepidemiology.
The proposed term "ET-plus" is based solely on clinical features and even these are not clearly defined. It is not based on differences in underlying etiology (e.g., genes) or pathology. As such, it is not grounded in underlying biological differences. The use of the term would have numerous research implications. As detailed here, it would greatly complicate or make impossible studies of the descriptive epidemiology of ET, association studies, cohort studies, and clinical trials in ET. Key Messages: The proposed designation has the potential to be very problematic for studies of the epidemiology of tremor. This, along with this questionable validity of the proposed nomenclature, calls its use into serious question.
对于大多数神经疾病来说，最重要的问题之一是病例定义。在神经流行病学领域，病例定义为从观察性研究到干预性研究、从病例对照研究到队列研究以及从描述性研究到分析性研究等各种研究的设计、进行和解释提供了信息。对于特发性震颤（essential tremor，ET）这一最常见的神经疾病之一，病例定义的问题尤为重要。尽管传统上认为它是一种单色疾病，但近年来其临床表型已经扩大。在最近关于震颤的共识声明中，有人提议将一种新的、暂定和不确定定义的实体与 ET 分离，其特征是除了动作震颤外还有其他神经体征。这个实体将被称为“ET-plus”。本文的目的是讨论所提议的命名法对 ET 神经流行病学研究的影响。
拟议的术语“ET-plus”仅基于临床特征，甚至这些特征也没有明确界定。它不是基于潜在病因（例如基因）或病理学的差异。因此，它不是基于潜在的生物学差异。该术语的使用将产生许多研究影响。如这里详细讨论的那样，它将极大地复杂化或使 ET 的描述性流行病学研究、关联研究、队列研究和 ET 的临床试验变得不可能。
拟议的指定有可能对震颤流行病学的研究产生非常大的问题。再加上拟议命名法的这种可疑有效性，使其使用受到严重质疑。
