Relapse prevention in major depressive disorder after successful ECT: a literature review and a naturalistic case series

Objective: Medication-resistance in major depressive disorder (MDD) may be related to high relapse rates after successful ECT when continued medication (C-MED) is used to prevent relapse. An alternative could be to continue ECT (C-ECT). Method: Patients with medication-resistant MDD responding to ECT were offered C-ECT without medication. Follow-up was 6 months. Publications from a literature search were screened against prespecified criteria. Results: With C-ECT the 6-month relapse-rate was 50% (6/12, 95%CI:21-79) in our medication-resistant group. In the review we found with C-ECT 29% (7/24,CI:13-51) in 'unknown' medication resistance and no data about medication-resistant depression. With C-MED at 6 months: no data were found concerning medication-resistant depression, 28% (35/124,CI:20-36) in 'unknown' resistance and 13% (2/15,CI:2-41) in non-resistance. With C-MED at 12 months, 73% (16/22,CI:50-90), 50%(16/32,CI:32-68) and 27% (8/30,CI:12-46) were found, respectively. Conclusion: The efficacy of C-MED is related negatively to medication resistance before ECT. This may also be the case for C-ECT. Further studies with C-ECT are urgently needed.