Case Control Study
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World J Psychiatry. Sep 19, 2022; 12(9): 1169-1182
Published online Sep 19, 2022. doi: 10.5498/wjp.v12.i9.1169
Delayed improvements in visual memory task performance among chronic schizophrenia patients after high-frequency repetitive transcranial magnetic stimulation
Xiang-Dong Du, Zhe Li, Nian Yuan, Ming Yin, Xue-Li Zhao, Xiao-Li Lv, Si-Yun Zou, Jun Zhang, Guang-Ya Zhang, Chuan-Wei Li, Hui Pan, Li Yang, Si-Qi Wu, Yan Yue, Yu-Xuan Wu, Xiang-Yang Zhang
Xiang-Dong Du, Zhe Li, Nian Yuan, Ming Yin, Xue-Li Zhao, Xiao-Li Lv, Si-Yun Zou, Jun Zhang, Guang-Ya Zhang, Chuan-Wei Li, Suzhou Guangji Hospital, Affiliated Guangji Hospital of Soochow University, Suzhou 215008, Jiangsu Province, China
Hui Pan, Li Yang, Department of Psychiatry, Third People’s Hospital of Changshu, Changshu 215501, Jiangsu Province, China
Si-Qi Wu, School of Psychology and Mental Health, North China University of Science and Technology, Langfang 065201, Hebei Province, China
Yan Yue, Yu-Xuan Wu, Department of Psychiatry, Medical College of Soochow University, Suzhou 215000, Jiangsu Province, China
Xiang-Yang Zhang, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
Author contributions: Du XD contributed to the project administration, funding acquisition, supervision, wrote the review and editing; Li Z contributed to clinical data collection, wrote review and editing; Yuan N contributed to the data curation, investigation; Yin M, Zhao XL, Lv XL, Zou SY, Zhang J, Li CW, Pan H, Yang L, Wu SQ, Yue Y and Wu YX contributed to the conceptualization, data curation and investigation; Zhang XY contributed to the formal analysis, wrote the original draft; Du XD, Li Z and Yuan N have congtributed equally to this work.
Supported by Key Diagnosis and Treatment Program of Suzhou, No. LCZX201919 and No. LCZX202016; The Scientific and Technological Program of Suzhou, No. SS201752 and No. SS202069; and Introduction Project of Suzhou Clinical Expert Team, No. SZYJTD201715.
Institutional review board statement: This study obtained approval from the Institutional Review Board of Suzhou Guangji Psychiatric hospital. All methods were performed in accordance with the Declaration of Helsinki.
Informed consent statement: Each subject provided written informed consent to participate in the study after a researcher staff explained the whole study to each of them.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: The data will be available on request from the readers.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xiang-Yang Zhang, Doctor, Professor, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, No. 16 Lincui Road, Chaoyang District, Beijing 100101, China. zhangxy@psych.ac.cn
Received: February 28, 2022
Peer-review started: February 28, 2022
First decision: April 18, 2022
Revised: April 24, 2022
Accepted: July 22, 2022
Article in press: July 22, 2022
Published online: September 19, 2022
Processing time: 204 Days and 10 Hours
ARTICLE HIGHLIGHTS
Research background

At present, antipsychotic drug therapy has little effect on the improvement of some psychiatric symptoms in schizophrenia patients, and drug therapy is not acceptable due to the unbearable adverse drug reactions. There is growing evidence that repetitive transcranial magnetic stimulation (rTMS) is effective for both positive and negative symptoms of schizophrenia.

Research motivation

Schizophrenia has brought great burden to the whole society with high morbidity and disability rate. The United Kingdom and the United States spend around 2% of GDP each year on the treatment, care and rehabilitation of people with schizophrenia. In particular, long-term hospitalization of patients wastes a large number of medical resources, and the existence of negative symptoms is one of the important reasons for long-term hospitalization of patients. Therefore, the use of rTMS adjuvant therapy to explore the possibility of improving the negative symptoms of patients, to promote the remission of patients, improve the social function and quality of life of patients, has good social and economic benefits.

Research objectives

In this study, we assessed the therapeutic effects and safety of left dorsolateral prefrontal cortex (DLPFC) high-frequency rTMS on negative symptoms of schizophrenia. We evaluated the efficacy of rTMS on recognition in patients with chronic schizophrenia.

Research methods

This was a randomized, sham-controlled, double-blinded trial. Patients diagnosed with schizophrenia on stable antipsychotic treatment were randomly assigned to active rTMS treatment group (n = 25) or a sham rTMS treatment group (n = 22). 25 patients in the active rTMS group received 10-Hz 110% motor threshold rTMS, while 22 patients were subjected to sham rTMS, both being given 4-wk treatment (5 d/wk). Efficacy of negative symptom was assessed with the Scale for the Assessment of Negative Symptoms (SANS), the Positive and Negative symptom scale (PANSS) at baseline, the end of 4 and 8 wk. The cognitive function was assessed with Cambridge Neuropsychological Test Automated Battery at baseline, the end of 4 and 8 wk. The side effects were assessed with TESS at baseline and the end of 4 wk.

Research results

There were no significant differences in pattern recognition memory (PRM) performance metrics, SANS total score, SANS subscores, PANSS total score, and PANSS subscores between active and sham rTMS groups at the end of the 4-wk treatment period, but PRM performance metrics (percent correct and number correct) and changes in these metrics from baseline were significantly greater in the active rTMS group at week 8 compared to the sham group (all P < 0.05). Active rTMS treatment also significantly reduced SANS score at week 8 compared to sham treatment. Moreover, the improvement in visual memory was correlated with the reduction in negative symptoms at week 8. In contrast, there were no between-group differences in PANSS total score and subscale scores at either week 4 or 8 (all P > 0.05).

Research conclusions

High-frequency TMS can improve visual memory and reduce negative symptoms in patients with schizophrenia, but these effects are delayed, potentially due to the requirement for extensive neuroplastic changes within DLPFC networks.

Research perspectives

In the future, it is necessary to further explore more scientific treatment parameters and more sensitive assessment tools (such as SANS and neuropsychological assessment kits) for rTMS in the treatment of negative symptoms of schizophrenia, and carry out multicenter, large-sample studies.