Whether you do ECT (electroconvulsive therapy) or not, and research indicates that less than 8% of you actually perform it (Hermann et al, Am J Psychiatry 1998; 155:889-894), you need to know about it, because you will have to decide when to refer your treatment-resistant patients for it, and you will have to know what to say to them about it as they pepper you with a multitude of questions, as they always do (and should).
ECT is very effective, but the old figure of an 80% response rate no longer applies. Generally speaking, the only patients that you are going to refer to ECT are those who have failed multiple medication trials, and among these patients the response rate is closer to 60% (Prudic et al, Am J Psychiatry 1996; 153:985-982). Experts in the field have another estimate for the really treatment-resistant patients-those who not only have failed multiple meds but have significant character disorders. The response rate here is closer to 40%.
Still, ECT is very effective for the acute treatment of depression, but what about long-term? Again, the answer to this question depends on whether you are looking at the “old” days or the “new” days. In the days of 80-90% response rates for patients who were medication-naive, post-ECT pharmacotherapy entailed tricyclics and MAOIs; reported relapse rates on these regimens were a tiny 20%, compared to placebo relapse rates of about 50%. The best recent study to look at continuation pharmacotherapy randomly assigned 84 remitted post-ECT patients to 3 groups: placebo, nortriptyline (NT), and combined NT-lithium (Sackeim HA et al, JAMA 2001;285:1299-1307). Six month relapse rates were 84%, 60%, and 39%, respectively, a result that endorses lithium augmentation of tricyclics but shows a pretty high relapse rate even for this robustly treated group.
For these reasons, maintenance ECT is hot. And everybody loves the Gagne study (Gagne GG et al, Am J Psychiatry 2000;157:1960-1965). These Brown University researchers pulled off a great chart review study, in which they compared 29 chronically depressed patients who received maintenance ECT (generally monthly) combined with antidepressants with 29 ECT-treated patients who received only meds after their initial successful course of treatment. After 5 years, 78% of maintenance ECT patients stayed well, versus only 18% of the medication only group. A pretty dramatic endorsement of maintenance ECT, even taking into account the pitfalls of a retrospective study.
Ah, but what about those nasty ECT side effects? By far the most feared side effect is memory loss. There is a tendency for clinicians to minimize the severity of memory loss to patients who we strongly believe would benefit from ECT. But it’s important to be accurate about the risks. Patients are often told that the main problem is a brief period of confusion after each treatment, with some difficulty recalling events that happened over the course of the treatment. In fact, many patients suffer significant retrograde amnesia, an effect that is more pronounced for memory of impersonal, public events than it is for autobiographical events (Lisanby SH, Arch Gen Psychiatry. 2000;57:581-590). This means that many patients will forget about fairly major news or cultural events that happened months or even years before ECT.
Bilateral ECT causes worse amnesia than unilateral ECT, but the hitch here is that bilateral is usually more effective than unilateral. The latest news in technique is that bifrontal lead placement causes less cognitive impairment than the typical bitemporal placement, without sacrificing much in the way of efficacy (Bailine SH, Am J Psychiatry 2000;157:121-123).
Researchers can get quite fancy with their studies and jargon about memory loss, much of which tends to distance us from the reality as experienced by our patients. But in fact, patients do complain about it, and a recent British review of all studies assessing patients’ views of ECT found that at least 30% of patients report that they had experienced “persistent or permanent” memory loss due to ECT (Rose D, BMJ 2003;326:1363). It wasn’t clear how severe these instances of memory loss were, and obviously there are many patients who gladly trade away a life of depression for some haziness about events a few months back.
ECT is effective, and we’re refining the technique, but staying up to date is key–both for your patient’s mood and memory.
TCR VERDICT: ECT: Bifrontal for memory; maintenance for remission