Older patients (>55) with a psychotic depression and complete remission within the first four electroconvulsive therapy sessions are the ones with the best chance of remaining relapse free for at least 6 months (10% relapse rate vs. 63% others), presented by Pascal Sienaert, MD, PhD, reported at the annual congress of the European College of Neuropsychopharmacology.

This conclusion is based on the results of two prospective studies by ResPECT – the Research in Psychiatry and ECT by the Flemish-Dutch Research Consortium – which, in turn, confirm the findings of an earlier metaanalysis of 32 studies including 702 patients conducted by investigators at Trinity College Dublin, noted Dr. Sienaert, a psychiatrist at the Catholic University of Leuven (Belgium) Academic Center for ECT and Neuromodulation.

That being said, it’s now clear that adequate maintenance therapy after successful ECT is the best way to reduce the risk of relapse, he said. The metaanalysis showed that continued use of antidepressant medications after successful ECT halved the 6-month risk of relapse, with an impressive number needed to treat of 3.3. Yet, the 12-month risk of relapse remained substantial, at 51%, and the Irish investigators stressed that maintenance treatment strategies need to be improved.(Neuropsychopharmacology. 2013 Nov;38[12]:2467-74).

Note: variable ECT schedules can improve results, and can be even weekly for years, and it’s best to use antidepressants after ECT to reduce relapse rate by 1/2 compared to no meds. Response rates to ECT is 87% for depression onset > age 55 (vs. 67% for less 55), and even higher with psychotic symptoms. Patients with vascular risk factors like DM, HTN, smoking, high cholesterol, CAD, stroke disease had rates of 58% response vs. 80% for no vascular risk factors. Interestingly, antidepressants are only 38% with no vascular disease and 32% with vascular disease.