Disease progression to bipolar disorder among adolescents and young adults with antidepressant-resistant and antidepressant-responsive depression: Does antidepressant class matter?

RNA editing-based biomarker blood test for the diagnosis of bipolar disorder: protocol of the EDIT-B study

INTRODUCTION

Misdiagnosis of bipolar disorder (BD) can lead to ineffective treatment, increased risk of manic episodes, and increased severity. Objective diagnostic tests or precise tools to diagnose BD and distinguish it from major depressive disorder (MDD) in depressed patients are lacking.

AIM

To assess the external diagnostic validity of a blood-based test using an RNA epigenetic signature for the differential diagnosis of BD versus MDD in patients with depression.

METHODS AND ANALYSIS

Multicentre cross-sectional study including an adult sample of inpatients or outpatients diagnosed with BD or MDD, currently treated for a major depressive episode. A structured diagnostic interview based on validated scales will be conducted. Sociodemographic variables, clinical history, toxic consumption, current treatment and quality of life will be assessed. Blood samples will be obtained and stored at -80 °C until RNA sequencing analysis. The EDIT-B is a blood-based test that combines RNA editing biomarkers and individual data (e.g., age, sex, and tobacco consumption). The clinical validation performance of the EDIT-B will be evaluated using the area under the curve, sensitivity, specificity, positive and negative predictive values, and likelihood ratios.

ETHICS AND DISSEMINATION

The principles of the Declaration of Helsinki 2013, precision psychiatry research and good clinical practice will be followed. The Research Ethics Committees of the participating centres approved the study. Participants will receive an information sheet and must sign the informed consent before the interview. Participants' data will be pseudonymized at the research sites. Any publication will use fully anonymized data. Publications with the final study results will be disseminated in international peer-reviewed journals and presented at international conferences.

STUDY REGISTRATION

This study has been registered on clinicaltrials.gov (NCT05603819). Registration date: 28-10-2022.

The role of gut microbiota and metabolomic pathways in modulating the efficacy of SSRIs for major depressive disorder

This study aims to explore the mechanism by which gut microbiota influences the antidepressant effects of serotonin reuptake inhibitors (SSRIs) through metabolic pathways. A total of 126 patients were analyzed for their gut microbiota and metabolomics. Patients received SSRI treatment and were categorized into responder and non-responder groups based on changes in their Hamilton Depression Rating Scale (HAMD-17) scores before and after treatment. The association between gut microbiota composition and the efficacy of SSRIs was investigated through 16S rRNA gene sequencing and metabolomic analysis, and a predictive model was developed. As a result, the study found significant differences in gut microbiota composition between the responder and resistant groups. Specific taxa, such as Ruminococcus, Bifidobacterium, and Faecalibacterium, were more abundant in the responder group. Functional analysis revealed upregulation of acetate degradation and neurotransmitter synthesis pathways in the responder group. The machine learning model indicated that gut microbiota and metabolites are potential biomarkers for predicting SSRIs efficacy. In conclusion, gut microbiota influences the antidepressant effects of SSRIs through metabolic pathways. The diversity and function of gut microbiota can serve as biomarkers for predicting the treatment response, providing new insights for personalized treatment.