Fran Lowry

May 02, 2013

ORLANDO, Florida — Bilateral prefrontal repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for the negative symptoms of schizophrenia, new research shows.

Preliminary results from a double-blind, randomized controlled trial showed that patients with schizophrenia or schizoaffective disorder who were treated with rTMS had a significant improvement in their negative symptoms, as assessed on the Scale for the Assessment of Negative Symptoms (SANS), that lasted for 4 weeks post treatment.

However, after 4 weeks, this beneficial effect diminished.

The findings were presented here at the 14th International Congress on Schizophrenia Research (ICOSR).

Effective Treatment Urgently Needed

Effective treatment options for the negative symptoms of schizophrenia are urgently needed, said study investigator Jozarni Dlabac-de Lange, MD, from the University of Groningen, the Netherlands.

"The outcome for patients who are suffering from negative symptoms is much worse, and there has not been a lot of research in this subgroup of patients because they are very difficult to include in studies," she told Medscape Medical News.

In addition, the few studies that have reported on the efficacy of rTMS treatment for negative schizophrenia symptoms have shown inconsistent results, Dr. Dlabac-de Lange said.

Dr. Jozarni Dlabac-de Lange

In the current study, the investigators randomly assigned 32 patients with schizophrenia or schizoaffective disorder and moderate to severe negative symptoms (Positive and Negative Syndrome Scale [PANSS] negative subscale ≥ 15) to receive either real (n = 16 patients) or sham (n = 16 patients) rTMS of the bilateral dorsolateral prefrontal cortex, at a frequency of 10 Hz in 10-second trains, with an intertrain interval of 50 seconds.

Each treatment lasted 20 minutes and was given in the morning and again in the afternoon. Patients were stimulated at 90% of the motor threshold.

The researchers found that there was a significant improvement in the SANS measure of negative symptoms in the rTMS group compared with the sham group 4 weeks after the treatment sessions stopped (P = .04); however, the effects diminished by 3 months (P = .14).

Additionally, there was no significant difference between the 2 groups on the PANSS negative symptom score at 4 weeks (P = .38) and at 3 months (P = .32).

"Results were good at first, so the next step is to try and see how we can enhance these treatment effects, perhaps by combining rTMS with psychosocial interventions, discovering the optimal treatment parameters and learning which of the negative symptoms show a better response to rTMS," Dr. Dlabac-de Lange said.

Cost an Issue for Many

Bruce Stevens, MD, from the University of Florida College of Medicine, in Gainesville, told Medscape Medical News that in his experience, rTMS works in some individuals.

However, the cost of the procedure makes it prohibitive for patients unless they have deep pockets, he said.

"What I want is for insurance to cover this. The cost is usually around $10,000 to $15,000 for a series, and most of the patients that I see can't afford that. The treatment is not 100% effective for everybody, is partially effective in some individuals, and in others will have no effect, and that is probably the motivation behind the lack of insurance," Dr. Stevens, who is also a member of the National Alliance on Mental Illness (NAMI), said.

"As a NAMI member, I see a lot of patients and their family members, hundreds, on the other side of the prescription pad, who would love to have TMS as a part of their arsenal if they could afford it," he said.

Dr. Dlabac-de Lange reported that she received an unconditional research grant for her study from AstraZeneca. Dr. Stevens reported no relevant financial relationships.

14th International Congress on Schizophrenia Research (ICOSR). Abstract S328. Presented April 25, 2013.


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