The disorder, which affects 2 percent of the population and is the fourth most common psychiatric problem (after phobias, alcohol and drug addiction, and depression), is usually treated with a combination of cognitive behavior therapy and antidepressants - serotonin reuptake inhibitors such as Defanyl and Zoloft. One-third of patients, however, don't respond to this approach.
The recent study, performed in France at 10 university hospital centers on 16 patients with OCD, presents considerable hope for this one-third of non-responsive patients. Microelectrodes were implanted in each patient''s subthalamic nuclei, and they were observed over a period of 10 months by a team of doctors, psychiatrists and other medical professionals.
Eight of the patients received active brain stimulation followed by a period of "placebo" stimulation. The other eight underwent "placebo" stimulation and then real stimulation. "This was a double-blind test," study leader Luc Mallet explained. "That is, neither the patients nor the doctors knew the periods of stimulation."
Throughout the trial, the patients' OCD behavior was carefully evaluated on various scientific scales. This behavior included the suffering caused by their obsessions, the time they consumed, and the patients' ability to control their thoughts and actions.
After only three months of brain stimulation, seven out of 10 patients improved to the extent that more than 25 percent of their symptoms disappeared. Patients were also evaluated in terms of quality of life: their capacity to return to normal family life, to make new friends, and to start working again.
After three months of brain stimulation, six out of 10 patients could do these things again, with only limited problems from the illness. Only 12 percent of the patients were this successful with placebo stimulation.