BACKGROUND While electroconvulsive therapy (ECT) is considered the gold standard for acute treatment of patients with otherwise treatment-resistant depression, ketamine has recently emerged as a fast-acting treatment alternative for these patients. Efficacy and onset of action are currently among the main factors that influence clinical decision making, however, the effect of these treatments on cognitive functions should also be a crucial point, given that cognitive impairment in depression is strongly related to disease burden and functional recovery. ECT is known to induce transient cognitive impairment, while little is known about ketamine's impact on cognition. This study therefore aims to compare ECT and serial ketamine administration not only with regard to their antidepressant efficacy but also to acute neurocognitive effects. METHODS Fifty patients suffering from depression were treated with either serial ketamine infusions or ECT. Depression severity and cognitive functions were assessed before, during, and after treatment. RESULTS ECT and ketamine administration were equally effective, however, the antidepressant effects of ketamine occurred faster. Ketamine improved neurocognitive functioning, especially attention and executive functions, whereas ECT was related to a small overall decrease in cognitive performance. CONCLUSIONS Due to its pro-cognitive effects and faster antidepressant effect, serial ketamine administration might be a more favorable short-term treatment option than ECT. LIMITATIONS As this research employed a naturalistic study design, patients were not systematically randomized, there was no control group and patients received concurrent and partially changing medications during treatment. CLINICAL TRIALS REGISTRATION Functional and Metabolic Changes in the Course of Antidepressive Treatment, https://clinicaltrials.gov/ct2/show/NCT02099630, NCT02099630.

中文翻译：

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连续服用氯胺酮与 ECT 对抑郁症患者的抗抑郁和神经认知作用。

背景 虽然电休克疗法 (ECT) 被认为是对其他难治性抑郁症患者进行急性治疗的金标准，但氯胺酮最近已成为这些患者的速效治疗替代品。疗效和起效是目前影响临床决策的主要因素之一，然而，鉴于抑郁症的认知障碍与疾病负担和功能恢复密切相关，这些治疗对认知功能的影响也应该是一个关键点。众所周知，ECT 会导致短暂的认知障碍，而氯胺酮对认知的影响则知之甚少。因此，本研究旨在比较 ECT 和连续氯胺酮给药的抗抑郁功效，以及急性神经认知作用。方法 50 名患有抑郁症的患者接受连续氯胺酮输注或 ECT 治疗。在治疗前、治疗期间和治疗后评估抑郁严重程度和认知功能。结果 ECT 和氯胺酮给药同样有效，但氯胺酮的抗抑郁作用发生得更快。氯胺酮改善了神经认知功能，尤其是注意力和执行功能，而 ECT 与认知能力的整体小幅下降有关。结论 由于其促认知作用和更快的抗抑郁作用，氯胺酮连续给药可能是比 ECT 更有利的短期治疗选择。局限性 由于本研究采用自然主义研究设计，患者没有被系统地随机化，没有对照组，患者在治疗期间同时接受和部分改变药物治疗。临床试验注册抗抑郁治疗过程中的功能和代谢变化，https://clinicaltrials.gov/ct2/show/NCT02099630，NCT02099630。