Research is increasingly showing a compelling link between depression and epilepsy. A study reported in the February 2000 issue of Annals of Neurology found that older adults who are clinically depressed are six times as likely to have a seizure as their peers, suggesting that a common factor may be the cause of both depression and seizures. In the October 2005 issue of the same journal Columbia University researchers reported that depression and suicide attempts may be due to underlying neurochemical pathways common to epilepsy development.
Not surprisingly, some individuals who have not responded to antidepressant therapy do respond to anticonvulsant medications such as Lamotrigine (Lamictal), Gabapentin (Neurontin), and Topiramate (Topamax). These medications are currently only approved for people who have seizures, but there are many case reports supporting their use for treatment resistant mood disorders.
Following this link to it's logical next step, researchers began to investigate the use of an epilepsy treatment called Vagus Nerve Stimulation as a treatment for depression. Results of a Vagus Nerve Stimulation pilot study showed that 40% of the treated patients displayed at least a 50 percent or greater improvement in their condition, according to the Hamilton Rating Scale for Depression. Half the patients also had at least a 50% improvement on the Montgomery Asberg Depression Rating Scale. The condition of several patients improved so substantially that they were able to return to work or other normal activities.
The device used for this therapy is often referred to as a "pacemaker for the brain". The system consists of a pulse generator and a nerve stimulator electrode that is usually programmed to send 30-second electrical impulses every 5 minutes to the left vagus nerve, via connecting leads. The generator is surgically placed in a pocket formed under the skin, below the left collarbone. It's disc shaped and about the size of an baby's palm. It is similar in appearance and size to a cardiac pacemaker. The surgery takes about forty-five minutes, and is considered a safe procedure with very little risk. The generator's "dosage of stimulation" is adjusted non-invasively through the skin using a computerized programmer.
Currently, the Vagus Nerve Stimulation Therapy System is approved for sale in the European Economic Area and in Canada as a treatment for depression in patients with treatment-resistant or treatment-intolerant major depressive episodes including unipolar depression and bipolar disorder (manic depression). In the US, Vagus Nerve Stimulation Therapy is at various levels of investigational clinical study as a potential treatment for depression, anxiety disorders, Alzheimer’s disease, and chronic headache/migraine. It was approved in the US in July 2005 as the first treatment specifically targeted at treatment resistant depression.
If you would like more information about Vagus Nerve Stimulation, you may learn more at: http://www.cyberonics.com.
