Background: We compared the antidepressant and cognitive effects of up to eight sessions of bilateral, brief pulse electroconvulsive therapy (ECT) administered twice (ECT x 2) or three times weekly (ECT x 3), to confirm that ECT x 3 acts more rapidly although the two schedules are equivalent in antidepressant outcome, and to establish whether ECT x 3 is indeed associated with more severe memory impairment.
Method: Patients with major depression, endogenous subtype were randomly assigned to ECT x 3 or ECT x 2 plus one simulated ECT per week, both up to a maximum of eight real ECT. Depression was evaluated by the Hamilton Depression Scale the day after each treatment and cognitive function by a test battery administered before and after the ECT series and at one month follow-up.
Results: Assessed categorically or parametrically, there was no significant difference in antidepressant outcome between the two schedules. Rate of response was significantly more rapid with ECT x 3 but was associated with more severe memory impairment.
Conclusions: Twice weekly administration is an optimum schedule for bilateral ECT unless clinical indications require the more rapid antidepressant effect of three times weekly treatment.