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Efficacy of bilateral repetitive transcranial magnetic stimulation for negative symptoms of schizophrenia: results of a multicenter double-blind randomized controlled trial

Published online by Cambridge University Press:  30 October 2014

J. J. Dlabac-de Lange ,
L. Bais ,
F. D. van Es ,
B. G. J. Visser ,
E. Reinink ,
B. Bakker ,
E. R. van den Heuvel ,
A. Aleman  and
H. Knegtering
J. J. Dlabac-de Lange*
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Psychiatry, Hanzeplein 1, Groningen, The Netherlands University of Groningen, University Medical Center Groningen, Rob Giel Research Centrum, Hanzeplein 1, Groningen, The Netherlands University of Groningen, University Medical Center Groningen, Department of Neuroscience and BCN Neuroimaging Center, Antonius Deusinglaan 2, Groningen, The Netherlands
L. Bais
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Neuroscience and BCN Neuroimaging Center, Antonius Deusinglaan 2, Groningen, The Netherlands Lentis Research, Center for Mental Health, Hereweg 80, Groningen, The Netherlands
F. D. van Es
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Psychiatry, Hanzeplein 1, Groningen, The Netherlands
B. G. J. Visser
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Psychiatry, Hanzeplein 1, Groningen, The Netherlands
E. Reinink
Affiliation:
Lentis Research, Center for Mental Health, Hereweg 80, Groningen, The Netherlands
B. Bakker
Affiliation:
Lentis Research, Center for Mental Health, Hereweg 80, Groningen, The Netherlands
E. R. van den Heuvel
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Epidemiology, Hanzeplein 1, Groningen, The Netherlands
A. Aleman
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Neuroscience and BCN Neuroimaging Center, Antonius Deusinglaan 2, Groningen, The Netherlands
H. Knegtering
Affiliation:
University of Groningen, University Medical Center Groningen, Department of Psychiatry, Hanzeplein 1, Groningen, The Netherlands University of Groningen, University Medical Center Groningen, Rob Giel Research Centrum, Hanzeplein 1, Groningen, The Netherlands University of Groningen, University Medical Center Groningen, Department of Neuroscience and BCN Neuroimaging Center, Antonius Deusinglaan 2, Groningen, The Netherlands Lentis Research, Center for Mental Health, Hereweg 80, Groningen, The Netherlands
*
* Address for correspondence: J. J. Dlabac-de Lange, Department of Psychiatry, University of Groningen, University Medical Center Groningen, Postbox 30.001, 9700 RB Groningen, The Netherlands. (Email: j.j.l.a.s.n.dlabac@umcg.nl)
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Abstract

Background.

Few studies have investigated the efficacy of repetitive transcranial magnetic stimulation (rTMS) treatment for negative symptoms of schizophrenia, reporting inconsistent results. We aimed to investigate whether 10 Hz stimulation of the bilateral dorsolateral prefrontal cortex during 3 weeks enhances treatment effects.

Method.

A multicenter double-blind randomized controlled trial was performed in 32 patients with schizophrenia or schizo-affective disorder, and moderate to severe negative symptoms [Positive and Negative Syndrome Scale (PANSS) negative subscale ⩾15]. Patients were randomized to a 3-week course of active or sham rTMS. Primary outcome was severity of negative symptoms as measured with the Scale for the Assessment of Negative Symptoms (SANS) and the PANSS negative symptom score. Secondary outcome measures included cognition, insight, quality of life and mood. Subjects were followed up at 4 weeks and at 3 months. For analysis of the data a mixed-effects linear model was used.

Results.

A significant improvement of the SANS in the active group compared with sham up to 3 months follow-up (p = 0.03) was found. The PANSS negative symptom scores did not show a significant change (p = 0.19). Of the cognitive tests, only one showed a significant improvement after rTMS as compared with sham. Finally, a significant change of insight was found with better scores in the treatment group.

Conclusions.

Bilateral 10 Hz prefrontal rTMS reduced negative symptoms, as measured with the SANS. More studies are needed to investigate optimal parameters for rTMS, the cognitive effects and the neural basis.

Keywords

Cognitiondorsolateral prefrontal cortexinsightnegative symptomsrandomized controlled trialsschizophreniatranscranial magnetic stimulation
Type
Original Articles
Information
Psychological Medicine , Volume 45 , Issue 6 , April 2015 , pp. 1263 - 1275
Copyright
Copyright © Cambridge University Press 2014 

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