An electrical treatment which zaps away symptoms of obsessive compulsive disorder (OCD) can help extreme sufferers unable to cope with everyday life, a ground-breaking study has shown.
The pacemaker-like therapy, known as Deep Brain Stimulation (DBS), involves passing a weak current through thin wire electrodes inserted deep into the brain.
Around 50 patients have undergone the pioneering treatment in the US.
The new findings presented today showed that some of the worst affected had managed to keep their symptoms under control for more than eight years with on-going DBS.
OCD affects around 1% of adults at any one time. The condition causes intrusive and obsessive thoughts, compulsive urges and repetitive actions such as washing hands and locking doors.
Celebrity sufferers include soccer star David Beckham, who in 2006 spoke about how he was compelled to arrange items in straight lines and pairs.
Jack Nicholson portrayed an author with OCD in the film As Good As It Gets.
The worst-affected patients spend almost every waking hour caught up in obsessive thoughts or performing senseless rituals. Many are housebound and some may be driven to thoughts of suicide.
The patients undergoing DBS were only considered for the "extreme" treatment after remaining chronically ill despite at least five years of aggressive conventional therapy.
Study leader Dr Benjamin Greenberg, a psychiatrist at Brown University in Providence, Rhode Island, said: "These techniques are promising but must be used with an abundance of caution.
"This is reserved for the small proportion of people who are severely disabled and have not benefited anywhere near adequately from very aggressive use of conventional treatments."
Dr Greenberg outlined his work on DBS today at the annual meeting of the American Association for the Advancement of Science in Washington DC.
The procedure involves inserting wires just over a millimetre thick into the brain's ventral capsule and nearby ventral striatum.
Both regions contain nerve fibres carrying signals thought to be important in OCD and related neuropsychiatric illnesses.
DBS has already been used successfully to halt the tremors and rigidity suffered by many thousands of Parkinson's disease patients around the world. It has also been tested as a treatment for depression.
In 2008 Dr Greenberg and US and Belgian colleagues reported success after treating 26 severely affected OCD patients with DBS for three years. In 73% of the patients, symptom ratings were reduced by 25%.
The new results showed that patients who improved initially continued to respond for eight or more years, demonstrating for the first time that the treatment could be a long-term solution for severe OCD.
Dr Greenberg stressed that none of the patients were cured, but the difference in their condition meant they could function well enough to live a near-normal life.
"What DBS really does is make you into an average OCD patient," he said.
When DBS stimulation was stopped due to a broken wire or drained batteries, patients returned to their pre-therapy state of depression, anxiety and OCD symptoms.
Side effects included excessive activity, or hypermania, in some patients.
Dr Greenberg has now started six projects using DBS to investigate the brain circuitry underlying OCD.
"We've learned that our conception of the brain circuitry that's involved in OCD, and in depression and other illnesses can be tested directly, and that we are on the right track with the anatomical models we are creating for this circuitry," he said.Reuse content