Short- and long-term evaluation of cognitive functions after electroconvulsive therapy in a Japanese population

Role of stimulus dose on neuropsychological functioning after electroconvulsive therapy in patients with major depressive disorder

Introduction

Electroconvulsive therapy (ECT) is the most effective treatment for patients suffering from treatment-resistant depression but its use is often limited by the concern for cognitive side effects. This study examines the effect of ECT on autobiographical and verbal memory compared to a healthy control group and the impact of the mean stimulus dose on cognition after ECT.

Methods

Autobiographical and verbal memory were assessed in depressed patients and healthy controls before the first and within one week after the last ECT treatment. Neuropsychological testing included the Autobiographical Memory Interview, the Verbal Learning and Memory Test and five tests from the Cambridge Neuropsychological Test Automated Battery. The mean charge delivered across the ECT series and the total number of sessions were examined in relationship to cognitive impairment after ECT using a multiple regression model.

Results

Autobiographical memory was significantly impaired after ECT treatment compared to healthy controls. Baseline scores were lower for depressed patients on all cognitive domains. Improvements in performance after ECT were found on tests for executive functions and working memory. Effects of the mean charge delivered on cognitive functioning after ECT were heterogeneous across cognitive domains but significant for verbal retrograde memory.

Conclusion

ECT led to autobiographical memory impairment. The relationship between mean charge delivered and cognitive performance is heterogeneous across different cognitive domains and requires further research. Significant effects of the mean charge delivered were found without a significant difference in cognitive functioning compared to a healthy control group.

Efficacy, safety and tolerability of formula-based unilateral vs bilateral electroconvulsive therapy in the treatment of major depression: A randomized open label controlled trial

Electroconvulsive therapy (ECT) remains the most effective treatment of depression, though it is still unclear which of its type is the most beneficial. The aim of this study was to compare the formula-based right unilateral ECT (RUL) with the fronto-temporal bilateral ECT (BT), in terms of their efficacy, safety and tolerability in patients with bipolar or unipolar depression. Ninety-one patients were randomly assigned to either BT (n = 45) or RUL (n = 46) ECT. Brief pulse width (0.5 ms) and a formula-based dosing method were applied. The clinical efficacy was assessed using the Hamilton Depression Rating Scale (HDRS-21).The somatic state was monitored throughout the ECT course and cognitive examination included: general cognitive performance, executive functions, visual-spatial functions, verbal fluency, verbal memory and autobiographical memory. Efficacy outcomes were not found to be significantly different between groups when using higher doses of energy in RUL ECT. Patients in RUL group were less likely to be confused and experienced increased blood pressure. The indices of general cognitive performance and verbal auditory memory were also significantly better this group, while BT ECT did not change these functions. Both ECT types resulted in a decline in the retrieval consistency of autobiographical memory that persists for at least three months and was significantly more marked in BT group as compared to RUL. In conclusion, formula-based RUL ECT does not differ from BT in antidepressant efficacy and has an advantage in terms of safety (lower incidence of increased blood pressure and fewer disturbances of consciousness) and tolerability (impact on cognitive functions).