Understanding electroconvulsive therapy-related anxiety: a prospective study. Aims of study: Although electroconvulsive therapy (ECT)-related anxiety is experienced by a significant proportion of patients, it remains understudied. Our aim was to study the course of ECT-related anxiety during ECT. Methods: Seventy-four patients with unipolar or bipolar depression, referred for ECT, were included. ECT-related anxiety was assessed the morning before each ECT session using the ECT-related Anxiety Questionnaire (ERAQ). Results: Female patients reported more anxiety than men (F (1,64.6) = 3.95, P = 0.05). Patients with a psychotic depression were more anxious before the start of ECT (F(64.8) = 4.57, P = 0.04), but experienced a significant decrease in ECT-related anxiety (t (63.9) = À3.63, P = 0.0006), whereas patients with a non-psychotic depression remained stable on anxiety during their ECT course (t (63,9) = 0.76, P = 0.45). In addition, we found a significant correlation between the decrease of ECT-related anxiety and the decrease of depression-severity (r = 0.35; P = 0.04). Conclusion: There are individual differences in ECT-related anxiety trajectories during ECT. Both female patients and patients with psychotic depression experienced more ECT-related anxiety before the start of ECT. The severity of ECT-related anxiety decreased significantly in patients with a psychotic depression, but remained stable in patients without a psychotic depression during ECT. In addition, patients who showed a stronger decrease in depression-severity also showed a stronger decrease in ECT-related anxiety. A better understanding of ECT-related anxiety trajectories can help in designing anxiety-reducing interventions.