Electroconvulsive therapy is an effective treatment for depression and other psychiatric conditions, but relapse rates at the end of the course may be as high as 50% (Bourgon & Kellner, 2000) unless some form of prophylactic treatment – generally medication, singly or in combination – is used. However, a small proportion of patients relapse despite these methods and such patients may require a further course of ECT in order to recover. Recently, interest has returned to the use of ECT as a prophylactic treatment in these cases, where illness may be severe and frequently recurrent. For a patient who has already responded to ECT, continuation therapy – if given at sufficient intervals – can reduce the overall number of treatments given in a 12-month period.

Before the advent of effective drug treatments, ECT was often used as a prophylaxis and although developments in pharmacotherapy have reduced its popularity, evidence suggests it is still used widely (Gupta et al, 2011). Indeed, for those patients who appear to respond only to ECT, continuation or maintenance ECT may be the treatment of choice. The American Psychiatric Association (2001) recommends that ECT facilities offer continuation ECT as a treatment option.

There is a lack of clarity about the terminology used with regard to continuation and maintenance ECT. In keeping with current practice regarding antidepressant prophylaxis, we would suggest the term continuation ECT for treatments designed to prevent relapse of an index episode of illness, and maintenance ECT to be applied to ECT usage as a prevention of further episodes or recurrence of illness. By custom, continuation ECT has been defined as prophylactic treatment over the first 6 months of remission.

Evidence for the efficacy of continuation ECT

In May 2003, NICE published its first guidance on ECT for depressive illness, schizophrenia, catatonia and mania, and in these guidelines recommended that ‘as the longer-term benefits and risks of ECT have not been clearly established, it is not recommended as a maintenance therapy in depressive illness’ (p. 6). In October 2009, however, the updated NICE guidelines on the management of depression in adults changed these recommendations (although only with regard to the use of ECT in depression).