background Medication resistance in major depressive disorder prior to ECT may be related to high relapse rates after successful ECT when continued medication is used to prevent relapse. An alternative could be to continue ECT.
aims We try to find evidence to answer the question if continuation- ECT is more effective than continuation-medication if medication resistance is taken into account.
method Patients with medication resistant major depressive disorder responding to ECT were offered continuation- ECT, without medication, to prevent relapse. Publications from a literature search using Medline and Excerpta Medica were screened.
results In our study 7 of 14 patients (50%, 95% confidence interval (CI): 23 - 77) with medication resistant depression relapsed within 6 months while on continuation- ECT. In the review we found with continuation-ECT a 6-month relapse rate of 29% (7/24, 95%-CI: 13 - 51) in 'unknown' medication resistance and no data about patients with medication resistant depression. With continuation- medication we found at 6 months no data about medication resistant depression, 28% (35/124,95%-CI: 20 - 36) relapse in 'unknown' resistance and 13% (2/15, 95%-CI: 2 - 41) in nonresistant depression. At 12 months we found 73% (16/22, 95%-ci: 50 - 90), 50% (16/32,95%-CI: 32 - 68) and 27% (8/30, CI: 12 - 46) respectively.
conclusion Available data, including those of our own study do not support the hypothesis that continuation- ECT is more effective than continuationmedication, if we take into account medication resistance. The efficacy of continuation medication is negatively related to medication resistance before ECT. This may also be the case for continuation- ECT Our clinical impression is that continuation- ECT can act positively and that relapse risk seems to be greatest within the first four months. Further studies with continuation- ECT are urgently needed.