Subanesthetic dose of ketamine for the antidepressant effects and the associated cognitive impairments of electroconvulsive therapy in elderly patients—A randomized, double‐blind, controlled clinical study

Abstract

Objectives We previously confirmed that low‐dose ketamine, as an adjunctive anesthetic for electroconvulsive therapy (ECT) in adult patients with depression, accelerates the effects of ECT and reduces the ECT‐induced learning and memory deficits. This study explored the efficacy and safety of low‐dose ketamine in elderly patients with depression. Methods Elderly patients with depression (N = 157) were randomly divided into two groups: propofol anesthesia group (group P) and propofol combined with ketamine anesthesia group (group KP). Patients in group KP were given low‐dose ketamine (0.3 mg/kg) for each ECT treatment; patients in group P were given the same amount of normal saline. Depressive symptoms and global cognitive functions were assessed using the 24‐item Hamilton Depression Rating Scale and Mini‐Mental State Examination, respectively, at baseline, 1 day after the 1st, 2nd, 4th, and 6th ECT sessions, and 1 day after the end of the ECT course. ECT effects of and complications were recorded. Results In total, 67 patients in group KP and 70 in group P completed the study. After the ECT, the response and remission rates were 82.09% and 73.13%, respectively, in group KP, and 81.43% and 68.57%, respectively, in group P; there was no statistical difference between groups. However, the incidence of cognitive function impairment was lower in group KP (10.4%) than in group P (25.7%), while different electrical dose and seizure duration were required during the course of treatment between the two groups. There was no difference in the complications of ECT between groups. Conclusions Low‐dose ketamine is safe as an adjunct anesthetic for elderly patients subjected to ECT. It has a protective effect on cognitive function and may accelerate the antidepressant effects of ECT.

Focal Points of the Preanesthesia Evaluation for Electroconvulsive Therapy in Patients with Depression: A Retrospective Analysis of Clinical Characteristics in Nonremission

“…Furthermore, the rational use of anesthetics such as propofol and ketamine can improve the e cacy of ECT [4][5][6] and may confer at least a short-term advantage in terms of improving depressive symptoms at the early stages of ECT 7 . A series of studies conducted by our research group also supported these views 8,9 .…”

Focal points of preanesthesia evaluations for electroconvulsive therapy in patients with depression: a retrospective analysis of clinical characteristics in nonremission

“…Furthermore, the rational use of anesthetics, such as propofol and ketamine, can improve the efficacy of ECT [ 7 – 9 ] and may confer at least a short-term advantage in terms of improving depressive symptoms at the early stages of ECT [ 10 ]. A series of studies conducted by our research group also supported these views [ 11 , 12 ].…”

The effect of ketamine on cognition, anxiety, and social functioning in adults with psychiatric disorders: A systematic review and meta-analysis

“…As shown in Figure 1 , from 856 records screened on title and abstract, 150 full texts were analyzed. The review process led to the selection of 22 studies (references reported in Table 1 ) referring to 22 independent RCTs (Loo et al, 2012 ; Zarate et al, 2012 ; Price et al, 2014 ; Rasmussen et al, 2014 ; Yoosefi et al, 2014 ; Alizadeh et al, 2015 ; Murrough et al, 2015 ; Singh et al, 2016 ; Zhong et al, 2016 ; Anderson et al, 2017 ; Fernie et al, 2017 ; Ray-Griffith et al, 2017 ; Chen et al, 2018 ; Taylor et al, 2018 ; Zhang et al, 2018 ; Dong et al, 2019 ; Fedgchin et al, 2019 ; Kheirabadi et al, 2019 ; Domany et al, 2020 ; Ochs-Ross et al, 2020 ; Keilp et al, 2021 ; Zou et al, 2021 ), 20 of these trials provided quantitative outcome data, therefore were included in the quantitative synthesis.…”