February 28, 2011

Brain Stimulation for OCD?

(Ivanhoe Newswire) -- New evidence shows when obsessive-compulsive disorder (OCD) becomes severe, deep brain stimulation (DBS) may help patients. However, one researcher says this method should be used with caution.

Benjamin Greenberg, M.D., a psychiatrist from Brown University and Butler Hospital, discussed the results of the technique he's helped pioneer at the annual meeting of the American Association for the Advancement of Science.

"These techniques are promising but must be used with an abundance of caution," Dr. Greenberg was quoted as saying. "This is reserved for the small proportion of people who are severely disabled and have not benefitted anywhere near adequately from very aggressive use of conventional treatments."

A little over 50 patients have had DBS for OCD in the United States since 2000. The procedure involves placing electrodes into the brain's ventral capsule and nearby ventral striatum, which contain fibers carrying signals between the thalamus, parts of prefrontal cortex, and other nodes in a network thought important in OCD. DBS won approval by the Food and Drug Administration in 2009 for extreme cases of OCD under its humanitarian device exemption.

In 2008, Greenberg and colleagues published results that showed 73 percent of patients with OCD who received DBS had at least a 25-percent reduction in their Obsessive Compulsive Scale score. The newest results show patients who improved initially and continue to receive stimulation generally improved for eight or more years.

"What DBS really does is make you into an average OCD patient," Greenberg said.

Greenberg points out that the difference between an extreme OCD patient and an average OCD patient is a difference of being nearly unable to function in society and being able to integrate into a more normal life. Even after surgery, that may still be a challenge for severe OCD patients, he said.

Patients who have DBS must either undergo repeated surgeries to replace batteries or continuously maintain a rechargeable battery pack. Some suffered side effects including excessive behavioral activation, especially in the early days of the research.

OCD affects about 1 percent of the population each year. Only a small subset of patients might qualify for the DBS procedure. To qualify, they must have very severe and chronically disabling illness despite at least five years of aggressive treatment.

SOURCE: The annual meeting of the American Association for the Advancement of Science, Feb. 18, 2011