Efficacy of ECT in bipolar and unipolar depression in a real life hospital setting

Background: It has been debated as to whether the polarity of mood disorder (bipolar versus unipolar) has prognostic significance for electroconvulsive therapy (ECT) outcome. In the treatment guidelines, ECT is recommended more readily for unipolar depression and not so for bipolar depression. This study aims to examine efficacy of bipolar and unipolar depression to ECT in a real life naturalistic setting.

Method: We studied the ECT parameters of all consecutive patients with a diagnosis of unipolar depression (recurrent depressive disorder, ≥2 episodes of depression) and bipolar depression referred for ECT between the months of July 2008 and December 2010 (BP-D: n=44) and (UP-D: n=106).

Results: When bipolar depression was compared to unipolar depression, the average motor seizure duration (mean=46.9 and 46.7, t=-0.06, p=0.94), number of ECTs required for improvement (mean=6.4 and 6.5, t=0.17, p=0.86), duration of inpatient stay after ECT initiation in days (mean=16.2 and 16.6, t=0.23, p=0.81) and improvement as assessed using a Likert scale (Mann-Whitney U, Z=-0.09, p=0.92) were not statistically different between the groups.

Conclusions: We did not find any difference in efficacy of ECT between the two forms of depression in real life setting. This calls for justification of use of ECT in all patients with depression irrespective of the type of illness polarity and inclusion of ECT as a routine treatment option in bipolar depression guidelines.