Vagus nerve stimulation and refractory depression

As highlighted in the recent systematic review by Stimpson et al (2002), we know little about the relative efficacies of the treatment interventions that are routinely deployed for those with depressive disorders that have not responded to standard, first-line treatment approaches. Accepted practice is, at best, systematic ‘trial and error’, with sequential antidepressant monotherapy and/or combinations of antidepressant drugs with ‘augmenting agents'. This haphazard medicinal approach to managing the patient with poorly responsive depressive disorder is compounded by the lack of available information on the effectiveness and optimal role for psychological treatment methods. Given the high prevalence of depressive disorders and their frequent presentation to both primary and secondary care health services, it is a source of embarrassment that we remain so ignorant. Nevertheless, it is against this backdrop of uncertainty that we must now evaluate the relative merits of a novel intervention that has captured considerable media and lay interest: vagus nerve stimulation (VNS™).