Doctors have hailed the results of early studies into a new treatment for patients with severe depression.
Trials carried out by US doctors on an anti-depression 'pacemaker' found the electrical device can significantly improve the mental health of patients.
The pacemaker, which is implanted in a person's chest, sends intermittent signals to the left vagus nerve in the brain. The device was originally used to treat patients with epilepsy. However, it was later found to have a positive effect on the part of the brain that regulates mood prompting these latest trials.
Doctors at the universities of South Carolina and Texas Southwestern Medical Center enrolled 75 patients with bipolar and unipolar depression into the study. All of the participants had severe depression and had failed to respond to at least two medications. The study found that after eight weeks of VNS treatment symptoms were reduced in 40% to 50% of patients and symptoms had completely vanished in one in five patients.
Mark George, of the University of South Carolina,the chief researcher said,"What really made us sit up and take notice was the fact that the symptoms completely vanished in about 20% of the patients."
A two-year follow-up study found that patients who did not show signs of improvement in the early trials had reported a reduction in symptoms later on.