Multimodal Pharmacological Study of Clinical Cohorts for Major Depressive Disorder - Sub-task 2: A Longitudinal Imaging-Proteomics Study on Suicidal Tendency and Mechanisms of Rapid Antidepressant Effects

This study focuses on the neurobiological changes in MDD patients with high suicidal risk during rapid antidepressant treatments, such as Esketamine and Electroconvulsive Therapy (ECT). Core ObjectivesEstablish a standardized longitudinal cohort for high-risk suicidal populations to ensure high-quality data for clinical transformation. Investigate the biological mechanisms of rapid-acting interventions by analyzing changes in brain function and molecular pathways. Develop predictive biomarkers to identify treatment responders early, thereby reducing ineffective trial-and-error treatments and lowering suicide risk. Methodology & Data CollectionThe study integrates multi-dimensional data across three critical time points: T0 (Baseline), T1 (Acute Phase/24h post-first treatment), and T2 (Remission Phase/4-6 weeks). Sample Cohort: A total of 130 participants (70 ECT, 30 Esketamine, 30 conventional medication). Multimodal Data Integration:Clinical Phenotyping: Standardized scales including HAMD-17 (Primary Indicator), C-SSRS (Suicide Assessment), and QIDS-SR16. Biological Omics: Whole Genome Sequencing (WGS), single-cell sequencing, proteomics, metabolomics, DNA methylomics, and gut metagenomics. Neuroimaging & Physiology: Functional MRI (fMRI), Diffusion Tensor Imaging (DTI), and 32-channel resting-state EEG. SignificanceBy capturing dynamic "treatment-response" trajectories, the project aims to move beyond descriptive symptoms to a system biology-based diagnosis. The findings are expected to provide scientific evidence for individualized intervention strategies and improve the efficiency of care for patients with treatment-resistant depression and acute suicidal ideation.