Effectiveness of electroconvulsive therapy in patients with "less treatment-resistant" depression by the Maudsley Staging Model.

INTRODUCTION

Electroconvulsive therapy (ECT) is an effective treatment for patients with mood disorders and is most often used for treatment-resistant cases. This study aimed to examine the effectiveness of ECT in a real-world treatment sample in a Chinese psychiatric hospital which included both treatment-resistant and nontreatment-resistant patients.

METHODS

An observational study of symptom outcomes from admission to the time of discharge was conducted with 37 inpatients diagnosed with unipolar or bipolar depression treated with ECT. Symptom severity was assessed with the 17-item Hamilton Rating Scales for Depression (HRSD-17) and treatment-resistance with the Maudsley Staging Model (MSM). Stratifying at the MSM median admission characteristics and symptom change was compared between patients who were treatment-resistant (n = 18) and who were not (n = 19). The outcome difference between groups was compared using analyses of covariance adjusted for baseline characteristics including symptom severity, followed by linear regression to identify factors associated symptom improvement in the entire sample.

RESULTS

The sample (n = 37) showed moderate treatment-resistance (MSM = 7.30 ± 1.13) at admission and both groups received 8.3 ± 2 ECT sessions. The treatment-resistant group had a smaller proportion of bipolar patients and more severe symptoms, but showed no significant difference from the nontreatment-resistant group in HDRS-17 scores at the time of discharge (adjusted means = 6.23 ± 1.00 vs. 5.94 ± 0.97, Partial η2  = 0.001, p = .845). Baseline symptom severity was the strongest correlate of reduction in HDRS-17 scores (β = 0.891, p < .001).

CONCLUSIONS

Symptom change with ECT in depression did not differ by level of treatment-resistance but was greatest among those with more severe baseline symptoms. Correlates of ECT effectiveness should be further evaluated in stratified randomized trials.