Electroconvulsive Therapy: A Scotland-Wide Naturalistic Study of 4826 Treatment Episodes

Electroconvulsive therapy (ECT) is an effective treatment option for several psychiatric disorders, including treatment-resistant depression, but there are concerns about potential adverse effects, particularly on cognition. This study describes ECT response and side effects in the Scottish ECT Audit Network.

Data collected from 4826 treatment episodes includes pre-ECT and post-ECT illness severity scores (Clinical Global Impression-Severity [CGI-S] and Montgomery-Åsberg Depression Rating Scale [MADRS]), diagnosis, age, sex, consent status, treatment year, treatment frequency, dose, and reported side effects. Descriptive statistics were used to assess the response to ECT by diagnosis, and logistic regression was used to investigate which factors influenced ECT response and side-effect occurrence.

CGI-S scale scores were reduced after ECT in all diagnoses. For patients with depression or bipolar depression, MADRS scores were also reduced after ECT. The most common side effect was headaches (29%). Increased age and increased CGI-S scores were significantly associated (multiple-testing corrected p < .05) with better treatment response and more cognitive side effects.

In a large observational outcome study of ECT, ECT appears to be effective (measured by reduction in CGI-S or MADRS scores) across a range of psychiatric diagnoses. Furthermore, increased age and increased illness severity scores at entry were the variables most significantly associated with treatment response and cognitive side effects.