An individualized program of follow-up treatment with electroconvulsive therapy (ECT) combined with an antidepressant was effective in preventing relapse in patients 60 years and older who had had a successful initial course of treatment for severe depression.
These findings add to evidence of the effectiveness and safety of ECT for depression treatment in this age group, and show, moreover, how ECT can be beneficial as a follow-up treatment to sustain recovery.
The Prolonging Remission in Depressed Elderly (PRIDE) study was a multi-center clinical trial aimed at comparing two strategies—one with, and one without ECT—for sustaining the effects of ECT treatment for depression in patients over 60
The PRIDE study tested right unilateral ultrabrief ECT, a mode of delivery for ECT designed to minimize cognitive side-effects.
In Phase 1 of the study, patients over 60 with depression received three ECT treatments per week combined with the antidepressant medication venlafaxine. Following treatment, of the 240 patients who entered the study, 62 percent met criteria for remission
The mean number of ECT treatments to remission was 7.3 (half of patients who remitted had fewer treatments and half more than 7.3).
In Phase 2 of the study, patients who had remitted in Phase 1 were randomly assigned to either a combination of venlafaxine and lithium, or venlafaxine with ECT.
Participants receiving ECT had four treatments over one month, plus additional ECT as needed while receiving venlafaxine.
Standard treatment with ECT involves a fixed schedule of follow-up treatment that may result in either over- or undertreating patients.
Again, we see the problems caused by trying to set fixed standards for medical care. Most individuals have too many differences in their body chemistry from the researched populations to foretell any success with a standard treatment.
The PRIDE investigators in the study tailored any follow-up ECT treatment to a patient’s symptom scores, administering ECT according to a set of predetermined symptom thresholds for treatment.
After 24 weeks, patients in the ECT plus medication group had significantly lower symptom scores (a difference of 4.2 in mean scores). Of those in the medication only group, 20.3 percent relapsed while 13.1 percent of those in the ECT plus medication group relapsed.
In addition to tracking the impact of treatment on depression, the investigators monitored cognitive function of all patients at each twice-monthly clinic visit.
There were no statistically significant differences in scores on a mental status examination that addresses orientation, memory, attention, and the ability to follow verbal and written instructions. Study follow-up continued for six months
While ECT may not have affected their test-taking ability, there are far deeper and more profound changes such treatment could cause. Of course, those are probably the changes that reduce the depression as well.
The authors also note that remission rates in this study are about twice that observed with antidepressant medications in similar age groups.
The relatively rapid effect of ECT—the mean of 7.3 treatments to remission spans about 2.5 weeks—can not only make a difference in quality of life but is potentially important in instances in which a person with depression is contemplating suicide and the need for immediate, effective relief from symptoms is urgent.
Concerns about ECT’s effect on cognition and memory have prompted exploration of alternative methods of administering ECT, including the approach used here, right unilateral ultrabrief ECT. Previous research has reported that this method preserves the effectiveness of ECT while reducing side effects.
The PRIDE study demonstrates that continuing ECT treatment following remission in a manner that is responsive to the needs of individual patients can maintain relief from depression and at the same time, avoid overtreatment