Department of Neurology, G.H. Sergievsky Center, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
Ther Adv Neurol Disord. 2013 Nov;6(6):353-68. doi: 10.1177/1756285613489591.
While essential tremor (ET) has traditionally been categorized as a pure motor disease, cross-sectional and longitudinal studies of cognition in ET have demonstrated that these patients may have cognitive dysfunction. Recent epidemiological studies demonstrate an association between ET (particularly with onset after age 65) and increased risk for cognitive impairment and dementia. Although existing studies have generally conceptualized cognitive changes in ET as consistent with a 'frontosubcortical' or 'corticocerebellar' profile, results from these same studies suggest that cognitive impairment in ET may in fact be heterogeneous. Furthermore, the underlying mechanisms remain uncertain. Cognitive changes could be a byproduct of the cerebellar dysfunction of ET itself; alternately, they may be a feature of concomitant neurodegenerative diseases that have been associated in several studies with ET, including Alzheimer's disease, Parkinson's disease or progressive supranuclear palsy. While the study of cognitive dysfunction in ET has received research attention in recent years, the results of these studies have not been translated into the clinical domain and clinical practice. This review first summarizes the current literature on the potential relationships between ET and cognitive change. We then suggest areas of further clinical evaluation and treatment; these suggestions are directed at physicians caring for ET patients who may demonstrate or complain of cognitive impairment. As we discuss, clinicians should ideally screen ET patients for possible signs or symptoms of cognitive impairment in addition to assessing for psychiatric comorbidity and quality of life. These recommendations are in contrast to most current clinical practice, which does not routinely include such assessment among ET patients. To our knowledge, there have been no pharmacotherapeutic trials to date of any agent for cognitive change associated with ET. We believe that studies for this indication are now called for. Future efforts in this direction will also need to take into account the pathobiology of cognitive changes in ET, which itself is an area that is ripe for future investigations.
虽然特发性震颤（ET）传统上被归类为一种纯粹的运动疾病，但对 ET 认知的横断面和纵向研究表明，这些患者可能存在认知功能障碍。最近的流行病学研究表明，ET（特别是 65 岁以后发病）与认知障碍和痴呆的风险增加有关。尽管现有研究通常将 ET 中的认知变化概念化为与“额-皮质下”或“皮质-小脑”模式一致，但这些研究的结果表明，ET 中的认知障碍实际上可能是异质的。此外，潜在机制仍不确定。认知变化可能是 ET 本身小脑功能障碍的副产品；或者，它们可能是与 ET 相关的几种同时发生的神经退行性疾病的特征，这些疾病包括阿尔茨海默病、帕金森病或进行性核上性麻痹。虽然近年来 ET 认知功能障碍的研究受到了关注，但这些研究的结果尚未转化为临床领域和临床实践。这篇综述首先总结了目前关于 ET 和认知变化之间潜在关系的文献。然后，我们提出了进一步临床评估和治疗的领域；这些建议针对的是照顾可能表现出或抱怨认知障碍的 ET 患者的医生。正如我们所讨论的，临床医生理想情况下应该筛查 ET 患者是否存在认知障碍的可能迹象或症状，除了评估精神病共病和生活质量。这些建议与目前大多数临床实践形成对比，后者通常不包括 ET 患者的此类评估。据我们所知，迄今为止，还没有针对与 ET 相关的认知变化的任何药物治疗试验。我们认为，现在呼吁针对这一适应症进行研究。未来在这方面的努力还需要考虑 ET 认知变化的病理生物学，这本身就是一个有待进一步研究的领域。
