The technique will gradually spread, but the Bellvitge hospital is the first public center in Catalonia that has implemented transcranial magnetic stimulation (TMS) to treat resistant depression. The advantage over standard alternatives, such as electroshocks or deep brain stimulation, is that it is a barely invasive therapy to address cases of depression that do not respond to drugs or psychological treatment, which represent between 20% and 40%.
The Bellvitge resistant depression treatment unit also uses repetitive TMS stimulation in cases of obsessive-compulsive disorder and, in the future, in other neuropsychiatric pathologies such as schizophrenia.
It is a neuromodulation procedure consisting of the application of focal electrical stimuli on different regions of the cerebral cortex using an electromagnetic coil placed on the scalp. It is very well tolerated by the patient, it does not require anesthesia, it does not cause cognitive deficits and the side effects are mild, explains Pino Alonso, head of Psychiatry at Bellvitge.
The first trials with rTMS were carried out at the beginning of this century and shortly after the technique was approved by drug authorities in Europe and the USA, although it was not sufficiently perfected from the point of view of psychiatry. “The coils that are placed on the scalp allowed one centimeter to enter the brain and the response was reduced and short-lived,” says Dr. Alonso. "In recent years, coils have been developed that allow electromagnetic stimulation to reach 3 centimeters and navigation techniques have been added that allow us to locate the areas of the brain that we want to study," she says.
Bellvitge psychiatrist Sergi López spent a stay in the psychiatry and neuromodulation laboratory of the Massachusetts General Hospital (Boston, USA) to learn about treatment protocols. The Catalan hospital, a reference for the Metropolitan South and Terres de l'Ebre region, estimates that it will be able to take on 80 patients a year. Each protocol consists of 30 sessions over six weeks, lasting between 10 and 20 minutes per session (previously 37 minutes). “It is applied on an outpatient basis, without anesthesia, it does not cause memory difficulties or loss of concentration and the side effects are normally limited to local discomfort or headache that resolves within 24 hours,” says Alonso. Each 30-session program costs public health between 3,000 and 4,000 euros.
The number of candidates for rTMS is significant, taking into account that between 10 and 12% of the general population may have depressive symptoms, of which between 20 and 40% will not respond to the usual treatments. The disease has a high incidence of work-related disabilities and has an impact on the person's functional deterioration.
What can patients expect from rTMS? Symptoms of depression may improve or disappear completely, at least temporarily. The percentage of positive response reaches between 50 and 60% of those treated, according to scientific evidence, the experience of internationally renowned clinical centers that use this technique and the first results obtained in Bellvitge, according to Dr. Alonso.
