ECT equally effective for bipolar and unipolar depression
MedWire News: Electroconvulsive therapy (ECT) is an effective treatment for patients with either bipolar or unipolar depression, and is associated with "encouraging" remission rates, a systematic review and meta-analysis of published studies shows.
"In bipolar depression, response to treatment with antidepressants is disappointing," observe Tom Birkenhäger (Erasmus Medical Center, Rotterdam, the Netherlands) and team.
The researchers explain that "ECT is routinely employed for the treatment of severe and treatment-resistant major depression. However, ECT treatment response differences between unipolar and bipolar depression remain unclear."
They add: "Since major differences exist in antidepressant treatment response between bipolar and unipolar depression, assessing the efficacy of ECT in bipolar depression is clinically relevant."
The team therefore searched the literature for relevant prospective and retrospective cohort studies comparing the efficacy of ECT in patients with unipolar or bipolar depression.
The primary outcome criterion was remission, defined as either a score of 7 or less on the 17-item Hamilton Rating Scale for Depression (HAM-D) or a score of 10 or less on the 24-item HAM-D.
In all, six studies, involving a total of 790 patients with unipolar depression and 316 with bipolar depression, met criteria for inclusion in the meta-analysis. Severity of depression at baseline was similar between unipolar and bipolar disorder patients in all six studies, the researchers note.
In four of the studies, bipolar disorder patients had a more severe course of illness than unipolar patients, as indicated by an increased number of mood episodes prior to the current episode or by a higher number of hospital admissions. Antidepressant drugs were discontinued at least 3 days before and during the ECT course in three studies, two studies did not provide information on concurrent use of antidepressants, and concurrent use of antidepressants was permitted in the remaining study.
The researchers found that overall remission rates were similar in both patient groups, at 50.9% in those with unipolar depression and 53.2% in those with bipolar depression.
Results from a random-effects analysis of the findings revealed that ECT showed similar efficacy regarding remission in unipolar and bipolar patients, at an odds ratio of 1.08 for unipolar versus bipolar disorder patients.
Birkenhäger and team conclude: "This meta-analysis provides evidence for the equal efficacy of ECT in unipolar and bipolar depression, despite bipolar disorder patients presenting with a more severe history of illness in most of the studies."
They add: "These remission rates are encouraging, especially for bipolar depression, since this type of major depression often proves to be relatively treatment resistant."
By Mark Cowen