By Will Boggs, MD
NEW YORK (Reuters Health) - Electrical stimulation of the vagus nerve, which originates in the brain and then branches widely throughout the neck, chest and abdomen, seems to help some people with Alzheimer's disease, according to a new study.
"The study primarily showed that VNS (vagus nerve stimulation) is well tolerated and safe in patients with Alzheimer's disease for up to 12 months," Dr. Magnus J. C. Sjögren from the Karolinska Institute in Sweden told Reuters Health.
"Furthermore, the study gave an indication that VNS may be of benefit, as a cognitive enhancing therapy," the researcher added
Dr. Sjögren and colleagues previously reported beneficial effects of VNS during a 6-month pilot study involving 10 patients with Alzheimer's disease. This report, in the Journal of Clinical Psychiatry, includes an additional 7 patients with follow-up for at least 1 year.
All the patients in the study chose to continue VNS therapy after one year of treatment, the investigators report.
Just over 40 percent of the participants showed improvement or no decline in mental abilities on a standard Alzheimer's disease assessment scale after a year of treatment, the results indicate.
Most patients completed the year without any changes in their cognitive-enhancing medications.
"It is important to emphasize that VNS is not an approved therapy for Alzheimer's disease, but that the study was performed in order to evaluate if it was safe and tolerated and if it could bring any benefit to patients with a severe chronic neurodegenerative disorder," Sjögren said.
"Future studies ... will have to tell whether VNS can enhance cognition or be of benefit in Alzheimer's disease," the researcher concluded.
SOURCE: Journal of Clinical Psychiatry, August 2006.