Minocycline for the treatment of mental health and neurological conditions: study protocol of a systematic review and meta-analysis

INTRODUCTION: Due to the anti-inflammatory, antioxidant and anti-apoptotic properties of minocycline, clinical trials have evaluated the potential of this drug to treat several psychiatric and neurological disorders, including major depressive disorder, schizophrenia, bipolar disorder, stroke and amyotrophic lateral sclerosis. This protocol proposes a systematic review (and potential meta-analysis) that aims to identify and critically evaluate randomised controlled trials of minocycline for treating psychiatric and neurological disorders. METHODS AND ANALYSIS: PubMed, Embase, Cochrane Central Register of Controlled Clinical Trials, PsycINFO and Cumulative Index to Nursing and Allied Health Literature (CINAHL) will be used to identify randomised controlled trials that used minocycline to treat psychiatric and neurological disorders. Double-blind, randomised, controlled, clinical trials of participants aged 18 years or older and written in English will be included in the review. Data will be extracted by two independent reviewers. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines will be followed and the Cochrane Collaboration's 'Risk of Bias' tool will be used to assess the risk of bias in all studies included in the systematic review. The Grading of Recommendations, Assessment, Development and Evaluation system will be used to access the overall quality of the level of evidence of the studies. If sufficient evidence is identified, a meta-analysis will be conducted using the standardised mean difference approach and reported with 95% CIs. Heterogeneity of evidence will be evaluated using the I2 model. ETHICS AND DISSEMINATION: This systematic review will evaluate only published data; therefore, ethical approval is not required. The systematic review will be published in a peer-reviewed journal and presented at relevant research conferences. TRIAL REGISTRATION NUMBER: CRD42020153292.