Assessment of treatment resistance criteria in non-invasive brain stimulation studies of schizophrenia

Jami Kronick; Priyadharshini Sabesan; Amer M Burhan; Lena Palaniyappan

doi:10.1016/j.schres.2021.06.009

Assessment of treatment resistance criteria in non-invasive brain stimulation studies of schizophrenia

Schizophr Res. 2022 May:243:349-360. doi: 10.1016/j.schres.2021.06.009. Epub 2021 Jun 26.

Authors

Jami Kronick¹, Priyadharshini Sabesan², Amer M Burhan³, Lena Palaniyappan⁴

Affiliations

¹ Schulich School of Medicine & Dentistry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5C1, Canada. Electronic address: jkronic3@uwo.ca.
² Department of Psychiatry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada. Electronic address: Priyadharshini.Sabesan@lhsc.on.ca.
³ Department of Psychiatry, University of Toronto, 250 College Street 8th floor, Toronto, Ontario M5T 1R8, Canada; Ontario Shores Centre for Mental Health Sciences, 700 Gordon Street, Whitby, Ontario L1N 5S9, Canada; Department of Psychiatry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada. Electronic address: burhana@ontarioshores.ca.
⁴ Department of Psychiatry, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7, Canada; Robarts Research Institute, University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada; Lawson Health Research Institute, 750 Base Line Road East Suite 300, London, Ontario N6C 2R5, Canada. Electronic address: lpalaniy@uwo.ca.

PMID: 34183208
DOI: 10.1016/j.schres.2021.06.009

Abstract

Novel treatment modalities, such as non-invasive brain stimulation (NIBS), typically focus on patient groups that have failed multiple treatment interventions. Despite its promise, the clinical translation of NIBS in schizophrenia has been limited. One important obstacle to implementation is the inconsistent reporting of treatment resistance in the clinical trial literature contributing to heterogeneity in reported effects. In response, we develop a numerical approach to synthesize quality of assessment of Treatment-Resistant Schizophrenia (TRS) and apply this to studies investigating therapeutic response to NIBS in patients with schizophrenia. Literature search conducted through PubMed database identified 119 studies investigating Transcranial Magnetic Stimulation and Transcranial Electrical Stimulation in treating resistant schizophrenia symptoms. A quality score out of 11 was assigned to each study based on adherence to the international consensus guidelines for TRS developed by the Treatment Response and Resistance in Psychosis (TRRIP) group. Results revealed an overall paucity of studies with thorough assessment and/or reporting of TRS phenomenon, as evidenced by a mean quality score of 3.38/11 (SD: 1.01) for trials and 5.16/11 (SD: 1.57) for case reports, though this improved minimally since the publication of consensus criteria. Most studies considered treatment-resistance as a single dimensional construct by reporting resistance of a single symptom, and failed to establish treatment adherence, resistance time course and functional impairment. We conclude that the current NIBS literature in schizophrenia do not reflect its true effects on treatment-resistance. There is an urgent need to improve assessment and reporting standards of clinical trials that target TRS.

Keywords: Non-invasive brain stimulation; Schizophrenia; Transcranial electrical stimulation; Transcranial magnetic stimulation; Treatment resistance.

Publication types

Review
Research Support, Non-U.S. Gov't

MeSH terms

Brain / physiology
Humans
Schizophrenia* / drug therapy
Transcranial Direct Current Stimulation* / methods
Transcranial Magnetic Stimulation / methods