Depression Remission and Response Rates and Anxiety Response as a Predictor of Depression Response in a Community ECT Clinic

Objective: To assess depression response and remission rates with electroconvulsive therapy (ECT) in a community clinic and to identify factors predicting success in treatment. Methods: We identified 35 patients by a retrospective chart review with a diagnosis of major depressive disorder or depressive disorder not otherwise specified (according to the Diagnostic and Statistical Manual of Mental Disorders IV-TR) who were treated with an acute series of ECT at the Pine Rest ECT Clinic from March, 2014 to March, 2015. Clinical variables, demographics, depression response rates (based on Patient Health Questionnaire-9; PHQ-9), and anxiety response rates (based on Generalized Anxiety Disorder 7-item) were analyzed. Results: Depression response (defined as [≥] 50% reduction in PHQ-9 score) and remission rates (defined as final PHQ-9 score < 5) were 54.3% and 31.4%, respectively. This was a highly treatment resistant sample, with an average of 5.3 antidepressant failures prior to initiating ECT. Logistic regression analysis found that depression response rates were predicted by an improvement in anxiety symptoms (odds ratio 1.41; 95% confidence interval, 1.11, 1.78). Additionally, patients with initial severe anxiety scores were less likely than other patients to exhibit a response in depression (p = .027). Conclusion: Almost half of this sample of patients with treatment resistant depression did not respond to ECT in this community-based clinic. Patients who experienced a response in anxiety symptoms were more likely to experience a depression response while those with severe anxiety were less likely to respond.