The results of a 60-patient pilot project into the use of the Vagal Nerve Stimulator (VNS) to treat depression has been announced by the stimulator's manufacturer, Cyberonics.
In people with epilepsy, VNS involves inserting an implant under the skin of the upper chest and vagal nerve area of the neck. Nerve fibres in the vagal nerve carry information from the body’s organs to the brain, which are believed to be involved in producing seizures. It is suggested that stimulation of the vagal nerve may be able to disrupt epileptic activity.
The study has investigate the use of VNS in the treatment of patients with chronic or recurrent depression, the results of which have been published in the journal Neuropsychopharmacology.
Study patients had failed to respond to treatments in their current episode of depression.
Nearly a third of the 59 patients who took part in the 12 week study saw a reduction of 50 per cent or greater in the Hamilton Rating Scale for Depression, an important indicator of a patient's level of depression. The most common side-effect was voice alteration, which was generally mild and related to the level of stimulation.
Dr Harold Sackeim from the Department of Biological Psychiatry, New York State Psychiatric Institute/Columbia University and lead author of the report stated:
"These pilot results of VNS in a severely afflicted population are very encouraging and formed the basis for the larger pivotal study of VNS in depression that is being completed at this time. There is a significant need for a better and more tolerable long-term treatment in resistant depression - one that not only has short-term efficacy, but also has minimal side-effects, such that patients can continue treatment in the long-term to sustain response. These results encourage us that VNS may be such a treatment."