OCD treatment
As with many psychiatric disorders, behavioural therapy and medication are the frontline therapies for obsessive compulsive disorder (OCD). However, for an estimated 10–40% of patients, these approaches do not work. A third approach showing promise in these treatment-resistant cases is deep brain stimulation, or DBS.
Behavioural therapy
Cognitive behavioural therapy is commonly used to treat cases of OCD, in particular a form known as exposure and response prevention (ERP) therapy. Normally, someone with OCD will feel the compulsion to act on an obsession once it enters their head – washing their hands to ensure cleanliness, for example. ERP involves intentionally exposing oneself (either in real life or in the imagination) to a situation that evokes an obsession, but then not following through on the compulsive behavioural response. The idea is, through repeated exposure, to gradually reduce the anxiety associated with obsessive thoughts and thereby reduce the need to perform compulsions.
Medication
Most OCD medications target the serotonin neurotransmitter system. There are genetic studies that suggest OCD can be caused by insufficient levels of serotonin in the brain. To increase the amount of this neurotransmitter in synapses, drugs called selective serotonin reuptake inhibitors (SSRIs) are given. These drugs, which benefit around ~70% of patients, are also given to people with depression.
Deep Brain Stimulation
For people with severe, treatment-resistant obsessive compulsive disorder associated with prominent disability, there is hope that deep brain stimulation may offer symptom relief. Deep brain stimulation (DBS) requires surgery to insert electrodes deep into the brain, where they deliver electricity to alter the brain’s activity. The electrodes are left within the brain permanently, with a battery to power them being inserted in the patient’s chest. For OCD, the electrodes are normally placed in a part of the brain called the nucleus accumbens (which is part of the striatum).
DBS is typically offered to people with OCD who have trialled many different medications and who have undertaken several courses of intensive exposure therapy, but who still have significant symptoms affecting their quality of life. In such individuals, studies from treatment centres around the world have shown that DBS can reduce the severity of OCD symptoms, with some centres reporting a 35-50% reduction in severity. However, it is important to note that DBS is not a cure for OCD and more studies are needed to improve the safety and efficacy of this treatment.
