The effect of deep brain stimulation on motor and cognitive symptoms of Parkinson's disease: A literature review

Deep brain stimulator (DBS) implant surgery is considered a breakthrough in the treatment of Parkinson's disease, especially in cases where motor symptoms cannot be controlled through conventional drug treatment. Its benefits have been studied extensively in the literature, particularly in relation to motor symptoms. However, the disease's cognitive aspects have been studied to a lesser extent. OBJECTIVE: This systematic review aims to assess the effects of DBS surgery on motor and cognitive symptoms in patients with Parkinson's disease. METHODS: The search strategy included MEDLINE, LILACs, SCIELO and the Cochrane Library. Randomized clinical trials with DBS surgical intervention and Parkinson's disease were included. Of the 178 studies identified, 19 met the eligibility criteria. These studies were descriptively analyzed as regards to their results. RESULTS: Control of motor symptoms, as assessed by the UPDRS Part III scale, was found in all of the studies, pointing to great interest in this outcome and demonstrating an advantage of DBS over conventional drug treatment. Regarding cognitive aspects, heterogeneity in the choice of subjects studied and the use of different assessment tools for each was evident, hampering comparisons and leading to inconclusive results. CONCLUSION: This review provides a broad overview of the effects of DBS on Parkinson's disease symptoms. However, it is suggested that future studies be conducted to establish a gold-standard protocol for neuropsychological assessment, thereby enabling data comparison and more consistent conclusions.

脑深部电刺激（Deep Brain Stimulator, DBS）植入手术被视为帕金森病治疗领域的一项突破性技术，尤其适用于常规药物治疗无法控制运动症状的患者。该手术的治疗获益已在大量文献中得到广泛研究，尤其是针对运动症状方面。然而，针对该病认知维度的相关研究则相对匮乏。
研究目的：本系统综述旨在评估脑深部电刺激植入手术对帕金森病患者运动及认知症状的影响。
研究方法：本次检索覆盖MEDLINE、LILACs、SCIELO及Cochrane图书馆数据库。纳入针对脑深部电刺激手术干预与帕金森病的随机对照临床试验。在所检索到的178项研究中，仅19项符合入组标准。本研究对这些研究的结果进行了描述性分析。
研究结果：采用统一帕金森病评定量表（Unified Parkinson's Disease Rating Scale, UPDRS）第三部分进行评估，所有纳入研究均证实脑深部电刺激手术可有效控制患者的运动症状，这一结果凸显了该结局指标的重要研究价值，同时证明了脑深部电刺激手术相较于常规药物治疗的优势。针对认知层面的相关研究则显示，受试对象的选择标准及所采用的认知评估工具均存在显著异质性，这阻碍了不同研究间的横向比较，导致相关研究结论尚不明确。
研究结论：本综述全面梳理了脑深部电刺激手术对帕金森病症状的影响。但本研究建议，未来应开展相关研究以建立统一的神经心理学评估金标准方案，从而实现不同研究间的数据比较，并得出更具一致性的研究结论。