Conference Report from The American Association of Neurological Surgeons annual meeting 2006 is showing promise results in treatment refactory OCD:
SAN FRANCISCO, April 24 — Deep brain stimulation significantly reduced symptoms of obsessive compulsive disorder (OCD) according to long-term results of a pilot study reported today.
Four of eight patients followed for 36 months after implantation of the stimulator had a reduction of at least 35% in OCD symptoms and two more patients reduced symptoms by 25% to 35%, said Ali Rezai, M.D., chairman of the Cleveland Clinic Center for Neurological Restoration, at the American Association of Neurological Surgeons meeting here.
“Pharmacologic trials use a 25% improvement as the measure of efficacy,’ Dr. Rezai said in an interview. “We set the bar much higher in a group of patients who were much more disabled than those selected for drug trials.”
The OCD study was one of a pair of deep brain stimulation trials being reported here by Dr. Rezai and colleagues at Brown. Dr. Rezai will also present preliminary results tomorrow of a small prospective study of deep brain stimulation for treatment of intractable major depression.
In the depression study, deep brain stimulation was associated with progressive, long-lasting “meaningful improvement in psychiatric function despite a history of failed trails of multiple antidepressants, combination/augmentation pharmacotherapy, psychotherapy and multiple electroconvulsive therapy (ECT) courses,” according to Dr. Rezai and colleagues.
Six of nine patients in the depression trial have completed a 12-month follow-up, with an average reduction of 48% on the Montgomery-Asbert Depression Rating Scale (MADRAS), which approached but did not meet the formal definition of responder (50% reduction in MADRAS).
But half of the patients who completed 12 months of follow-up met the definition, with reductions of 67%, 70%, and 76% and a fourth patient had an improvement of 49%, Dr. Rezai said.
In both trials patients had long histories of failed therapies and significant disability, he said. “In the OCD studies these patients were extremely disabled-some could not even perform basic activities of daily living. In the depression study we had patients who had failed more than 100 ECT sessions with treatment to both sides of the brain. Again, a very, very disabled population.”
Both studies used Soletra (Medtronic) deep brain stimulators with lead configuration specific to the targeted disorder.
The OCD trial enrolled six men and four women, ages 21 to 58. At baseline the mean Yale-Brown Obsessive Compulsive score was 34.6 ± 0.6, with a score of 28 indicating extreme OCD.
Three weeks postoperatively, before stimulation began, the mean scores were 33.3±1.0, which suggests that insertion of the lead had no effect on OCD severity.
At 36 months, the mean Yale-Brown Obsessive Compulsive score was 22.3±2.1, which was significant (P<0.001). Of note, most of the improvement occurred early-the mean Yale-Brown Obsessive Compulsive score improved to 25±1.6 at 3 months, Dr. Rezai said. But he added that continued stimulation was associated with continuous improvement.
Stimulation was also associated with improvements in the Hamilton Depression Rating Scale, (P=0.015), the Hamilton Anxiety Rating Scale (P<0.001) and Global Assessment of Functioning (P<0.001).
Adverse effects included a small intracerebral hemorrhage after lead insertion in one patient. A number of acute effects including sadness, anxiety, euphoria or giddiness, jaw muscle tightness associated with dysarthria, and related changes in smell and taste sensations, occurred at time of stimulation but all reversed within minutes.
A benefit of deep brain stimulation was significant improvements in visuospatial skills as well as some aspects of visual and verbal memory.
The mean average age of the nine patients enrolled in the depression study was 27 and seven patients were women. All patients had severe, disabling depression for at least five years with symptoms refractory to at least three classes of antidepressants titrated to maximum doses and failure of combined therapy with at least two augmentation agents. Entry criteria also included a history of multiple failed ECT trials.
Adverse events reported in the depression trial included occipital pain, which required revision surgery of the connection. There were also transient stimulation-induced reports of hypomania, insomnia, dizziness, facial tingling and foot cramps.
Dr. Rezai concluded that deep brain stimulation, while not a cure, did allow the majority of patients in both studies to “return to much more functional and happy lives.”
Both trials were funded by Medtronic, but Dr. Rezai said he had no consulting relationship with the device maker.
The investigators pointed out that a more definitive test of the efficacy and tolerability of deep brain stimulation will require larger controlled trials.