ECT is highly effective in achieving remission in major depression. High rates of relapse after remission remain a limitation with ECT. Even with continuation treatments ( antidepressants or ECT) relapse rates are high. Relapse rates are likely to be higher in recent studies possibly due to changes in the patient population now receiving ECT. ECT is given to resistant/ chronic and severe depression and that maintaining remission longer is likely to be an extremely difficult task.
Ana Jelovac, Erik Kolshus and Declan M McLoughlin report the results of meta analysis of the relapse rates in major depression after successful ECT. All studies in adult age depression ( unipolar or bipolar) where relapse was determined clinically in prospective follow up of at least 3 moths after response or remission with ECT where included in this analysis.The primary outcome was cumulative relapse proportion at the 6-month follow-up after last ECT.
32 studies met inclusion criteria . By 6 months, 34 % of patients who achieved remission after ECT and treated with continuation pharmacotherapy had relapsed. Realpse rates were lesser in earlier studies. No studies were identified between 70s and easily 90s .When only modern studies were included, relapse rate was 38%. This reached 50% at one year. Relaspe among those using antidepressants during ECT where less than those who started them after ECT.Those on continuation ECT also relapsed at the same rate as those on continuation medications. Relapse rates were lower when Continuation ECT was combined with medications ( 20% at one year based on small number of studies).
Systematic review did not identify any long-term studies directly comparing outcomes in ECT vs medication-treated patients. studies included are small, underpowered and predominantly observational studies.Substantial variability seen.Very few RCTs on continuation therapies. There is not enough studies to comment on antidepressant options post ECT.
There is no clear consensus on optimal post ECT relapse treatment plan. APA suggest medication or continuation ECT for all (2001).Most research in ECT in recent times have been on optimising the treatment parameters rather than on this important question i.e. on maintaining remission.
Conclusion: Nearly 40% of patents will relapse in 6 months following remission with ECT combined with conitunation pharmacotherapy . Almost half will relapse at one year. Placebo samples generally indicate relapse rates approaching 80% in this group of highly resistant difficult to treat condition.
Summary of the article:
Jelovac A, Kolshus E, McLoughlin DM. Neuropsychopharmacology. 2013 Nov;38(12):2467-74