The Role of Electroconvulsive Therapy (ECT) in Bipolar Disorder: Effectiveness in 522 Patients with Bipolar Depression, Mixed-state, Mania and Catatonic Features

摘要

Bipolar disorder (BD) is a serious and extremely recurrent illness frequently associated with cognitive and functional deterioration that poses many treatment challenges [1]. Despite a growing armamentarium of psychotropic medications, many patients with BD remain refractory to pharmacological treatment, relapses are common and morbidity and mortality remain elevated [2-9]. Because of the high rate of treatment nonresponse, the use of complex polypharmacy has increased dramatically over the years [10, 11]. Although there are several examples of “rational polypharmacy” [12, 13] and anecdotal evidence that some BD patients may benefit from certain complex regimens, the increased reliance on polypharmacy occurred in the absenceof any controlled evidence. Indeed, the efficacy of combined treatment consisting of three or more medications is not demonstrated [14]. Whether “rational” or “irrational”, the medication burden associated with increased use of complex polypharmacy raises several concerns including increased switches rate, rapid cycling, treatment resistance, apart from adverse side effects [13] due to drug interactions [14] and patient nonadherence [15-17]. Concern about the efficacy of current treatments for BD has been particularly marked for bipolar depression: adjunctive second-generation anti-depressants over monotherapy with mood stabilizers do not seem to bring any benefit [16]. Moreover, a recent prospective naturalistic longitudinal study [18] reported a significantly lower likelihood of recovery in BD inpatients with depressive compared to those with manic episodes.Electroconvulsive therapy (ECT) has a unique place in the therapeutic armamentarium for BD; it has been shown useful as an acute treatment of severe depressive, manic and mixed states [19-25], in highly suicidal patients, in those presenting with catatonia, and in those with drugs refractory disease [26]. The limitations of pharmacotherapy indicate the need for a better definition of the role of ECT in BD. All BD treatment guidelines suggest that ECT should be applied only in pharmacotherapy-resistant or very severe cases [26-31]. Accordingly, ECT is not included as one of the first treatment options for either the manic or depressive phase, independently from the severity or the variety of clinical presentation.However, in clinical practice, there is a broad consensus on the use of ECT in several groups of patients with severe clinical pictures, often in situations of emergency, as a first-line treatment; in such cases, ECT should be considered earlier than psychotropic medications. This is the case of patients with suicidal ideation and behavior, severe weight loss, malnutrition, dehydration and globally exhausted for protracted depressive or manic episode, [32], severe mixed state and catatonia. On the other hand, there is a significant variability among psychiatrists on the timing of referring patients affected by treatment-resistant mood disorders for ECT. Most practitioners take into account ECT only when the patient have not responded to several pharmacological treatments; such attempts may last for months or years, prolonging the patient's suffering. The length of episode seems to correlate with treatment resistance and poor outcome after ECT, a key point to discourage the use of ECT as a ‘last resort’ option [33].Bipolar DepressionThe studies supporting the effectiveness of ECT in severe and refractory depression have been conducted mostly in patients with major depressive disorder (MDD). ECT in BD depression is less extensively studied [19, 22]. This is rather unexpected, because literature data showed significant differences in antidepressants’ efficacy between MDD and BD depression [16]. Not only depression in BD patients resulted less responsive than in MDD, but also the use of antidepressants may induce manic switching, mixed states (MS) and cycle acceleration [34, 35]. A better response to ECT was also observed in patients suffering from