Long-term follow-up on patient attitudes towards renewed ECT: A register-based cohort study.

Electroconvulsive therapy (ECT) is a safe and effective treatment for major depressive disorder (MDD). After receiving ECT for MDD there is a large risk of relapse within the first year. Patient attitudes towards renewed treatment could impact their decisions regarding future therapy. We conducted a nationwide cohort study, using data from Swedish registers. Patients with MDD who received ECT were followed up to six months after the initial ECT-series. We investigated if certain patient and treatment characteristics during the initial treatment were correlated to their attitude towards renewed ECT at the six-month follow-up. Logistic regression models were used to calculate adjusted odds ratios for predictors. The Bonferroni method was used to adjust significance levels for multiple testing. The study included 1917 patients. 51.1% of patients were positive, 27.6% were undecided and 21.3% were negative towards renewed treatment. Patients with response to treatment were less likely to have a negative attitude towards renewed ECT (odds ratio 0.32, 95% CI 0.25-0.41, P < 0.001). Moreover, patients with experience of ECT prior to the index series were less likely to have a negative attitude towards renewed ECT (odds ratio 0.44, 95% CI 0.34-0.58, P < 0.001). In order to minimize the risk of negative attitudes towards renewed ECT for MDD, treatment should primarily be reserved for patients that are likely to respond to ECT.

The effect of anaesthetic dose on response and remission in electroconvulsive therapy for major depressive disorder: nationwide register-based cohort study.

BACKGROUND: Electroconvulsive therapy (ECT) is a safe and effective treatment for major depressive disorder (MDD). ECT treatment effect relies on induced generalised seizures. Most anaesthetics raise the seizure threshold and shorten seizure duration. There are no conclusive studies on the effect of anaesthetic dose on response and remission rates with ECT for MDD. AIMS: We aimed to examine the effect of different dose intervals of anaesthetics on response and remission after ECT for MDD. METHOD: We conducted a nationwide cohort study, using data from Swedish registers. Low-, medium- and high-dose intervals, adjusted for age and gender, were constructed for each anaesthetic drug. Response and remission were measured with the Clinical Global Impression - Severity and Improvement scales (CGI-I and CGI-S), and a self-rated version of the Montgomery-Åsberg Depression Rating Scale (MADRS-S). Logistic regression models were used to calculate adjusted odds ratios for response and remission rates. RESULTS: The study included 7917 patients who received ECT for MDD during 2012-2018. Patients were given either thiopental (64.1%) or propofol (35.9%). Low-dose intervals of anaesthetics were associated with increased rates of response (CGI-I: odds ratio 1.22, 95% CI 1.07-1.40, P = 0.004; MADRS-S: odds ratio 1.31, 95% CI 1.09-1.56, P = 0.004) and remission (CGI-S: odds ratio 1.37, 95% CI 1.17-1.60, P ≤ 0.001; MADRS-S: odds ratio 1.31, 95% CI 1.10-1.54, P = 0.002). CONCLUSIONS: We found improved treatment outcomes with low- compared with high-dose anaesthetic during ECT for MDD. To enhance treatment effect, deep anaesthesia during ECT for MDD should be avoided.

Less memory complaints with reduced stimulus dose during electroconvulsive therapy for depression.

BACKGROUND: Electroconvulsive therapy (ECT) is an effective treatment for depression, but there is risk of cognitive adverse events. This risk has been partially attributed to electrical charge, thus the optimal electrical stimulus dose is still under discussion. The aim of this study was to evaluate how the risk of subjective memory worsening was changed after lowering stimulus dose during ECT for patients with major depression. METHOD: A retrospective register-based intervention study of the effects of reduced electrical charges for patients receiving ECT for depression was conducted. The primary outcome was subjective memory worsening and the secondary outcome change in effect on depressive symptoms. RESULTS: A total of 154 patients were enrolled in the study (High dosage group: n = 57; Lower dosage group: n = 97). Subjective memory worsening after ECT occurred in 44% of patients in the high dosage group and in 25% of patients in the lower dosage group(p = 0.014). There was no significant between-group difference in the anti-depressive effect of ECT. LIMITATIONS: The study was register-based and the two groups were not randomized. A large portion of patients were initially excluded due to missing data in the register. The study lacks a long-term follow up. CONCLUSION: After implementing a change of treatment protocol, that lowered ECT stimulus doses from high to moderate, the occurrence of subjective memory worsening was significantly reduced without compromising treatment results.