Non-Pharmacological Treatments for mood disordersECT TMS MST VNS DBS Neurosurgery
ECT still remains a controversial treatment for depression. It is a treatment that remains underused and is often misunderstood. It is effective in about 50% of patients with DTD and is approved by NICE for use in patients who are suffering from severe depression and/or if other treatments have not worked. ECT takes place in a hospital environment. Electrodes (conductors which passes electricity to the brain) are positioned on a patient’s head whilst the patient is asleep under a general anaesthetic and also having been administered a muscle relaxant by an anaesthetist. An electric current crosses the brain tissue causing a small seizure (fit). It is not clear how ECT works; but it can have a rapid onset of action and can benefit many depressed patients. Often “top up” sessions of ECT are required to maintain the patient ‘s ability to manage any residual depressive symptoms.
rTMS uses a magnet to activate the brain. It is performed in a clinical setting whilst the person remains awake and alert. A magnetic coil is carefully positioned on the patient’s scalp and a magnetic field induces an electric current targeting a small area of the brain involved in mood regulation. It is not as effective as ECT; but has fewer side effects. “Top ups” of TMS may be required. Studies are currently ongoing.
MST is a novel therapeutic intervention combining the efficacy of ECT with the minimal cognitive side effect profile of rTMS. Unlike ECT, the seizure is a focussed seizure, the target being the part of the brain called the prefrontal cortex. There is little spread of the seizure to deeper brain structures and the areas involved in memory are not affected.
The patient is given a general anaesthetic and a muscle relaxant in a hospital environment. A high strength magnetic field is used. Recovery time for MST is shorter than for ECT and there is less confusion following it. Response rates vary between 40-70% and remission rates 15-46%. Research into MST continues and it is not currently widely available.
VNS involves the surgical implantation of a pacemaker like device in the chest wall with a wire passing to the vagus nerve in the neck which is stimulated for 30 seconds every 5 mins or so, 24 hours a day. The treatment was first used as a treatment for epilepsy. Since 1998 it has been tested as a treatment for Difficult-to-Treat Depression (DTD). The treatment works very slowly leading to increasing benefit over months or years. Around 60-70% of people gain at least some benefit some of the time over the long term. Further research is required. NICE recommends special arrangements for clinical governance, consent, audit, or research.
Brain surgery that promotes behavioural or affective changes in humans is controversial. 1935-1950 saw the use of “frontal lobotomies” to treat psychiatric disorders. This resulted in major personality changes. The surgery was often carried out by inadequately trained surgeons using a crude technique to blindly insert cutting instruments into the brain. There was a high incidence of complications and side effects.
Now-a-days, the technique is more refined, and the term “psychosurgery” has been replaced by the term “neurosurgery for mental disorders”. It is rarely used in clinical practice.
Deep brain stimulation (DBS) has been used to treat Parkinson’s disease since 1987. In psychiatry, it is still in an investigational stage; but has been approved in the USA to treat obsessive-compulsive disorder, though a couple of large studies in depression were negative. It is a refined alternative to psychosurgery and involves the use of an electrical stimulus on a specific target in the brain. Its superiority to psychosurgery remains to be scientifically proven.
- ECT is a highly effective treatment that is currently underused.
- rTMS may be an alternative to ECT; but is not currently as effective.
- VNS is not an alternative to acute ECT; but may be an alternative to maintenance ECT and for patients with chronic depression or frequent episodes.
- MST and DBS are not currently treatment options, and more research is needed
- Psychosurgery is an “end-stage” option for Difficult-to-treat Depression.
- There are other talking therapies available to treat difficult-to-treat Depression. Click here to read more about talking therapies.