Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy; Bipolar and Depressive Disorders Unit, Institute of Neuroscience, Hospital Clinic, University of Barcelona, IDIBAPS, CIBERSAM, 170 Villarroel st, 12-0, 08036 Barcelona, Catalonia, Spain.
Bipolar and Depressive Disorders Unit, Institute of Neuroscience, Hospital Clinic, University of Barcelona, IDIBAPS, CIBERSAM, 170 Villarroel st, 12-0, 08036 Barcelona, Catalonia, Spain.
Eur Neuropsychopharmacol. 2020 Jun;35:49-60. doi: 10.1016/j.euroneuro.2020.03.017. Epub 2020 May 12.
Major Depressive Episode (MDE) is a transdiagnostic nosographic construct straddling Major Depressive (MDD) and Bipolar Disorder (BD). Prognostic and treatment implications warrant a differentiation between these two disorders. Network analysis is a novel approach that outlines symptoms interactions in psychopathological networks. We investigated the interplay among depressive and mixed symptoms in acutely depressed MDD/BD patients, using a data-driven approach. We analyzed 7 DSM-IV-TR criteria for MDE and 14 researched-based criteria for mixed features (RBDC) in 2758 acutely depressed MDD/BD patients from the BRIDGE-II-Mix study. The global network was described in terms of symptom thresholds and symptom centrality. Symptom endorsement rates were compared across diagnostic subgroups. Subsequently, MDD/BD differences in symptom-network structure were examined using permutation-based network comparison test. Mixed symptoms were the most central and highly interconnected nodes in the network, particularly agitation followed by irritability. Despite mixed symptoms, appetite gain and hypersomnia were significantly more endorsed in BD patients, associations between symptoms were highly correlated across MDD/BD (Spearman's r = 0.96, p<0.001). Network comparison tests showed no significant differences among MDD/BD in network strength, structure, or specific edges, with strong edges correlations (0.66-0.78). Upstream differences in MDD/BD may produce similar symptoms networks downstream during acute depression. Yet, mixed symptoms, appetite gain and hypersomnia are associated to BD rather than MDD. Symptoms during mixed-MDE might aggregate according to 2 different clusters, suggesting a possible stratification within mixed states. Future symptom-based studies should implement clinical, longitudinal, and biological factors, in order to establish tailored therapeutic strategies for acute depression.
重度抑郁发作（MDE）是一个横跨单相抑郁（MDD）和双相障碍（BD）的跨诊断学的结构。预后和治疗意义需要对这两种疾病进行区分。网络分析是一种新的方法，它描绘了精神病理学网络中症状的相互作用。我们使用数据驱动的方法研究了急性抑郁的 MDD/BD 患者中抑郁和混合症状之间的相互作用。我们分析了 2758 名来自 BRIDGE-II-Mix 研究的急性抑郁的 MDD/BD 患者的 7 项 DSM-IV-TR 重度抑郁发作标准和 14 项基于研究的混合特征标准（RBDC）。通过症状阈值和症状中心性来描述整体网络。比较了不同诊断亚组的症状表达率。随后，使用基于置换的网络比较检验，检查了症状网络结构中 MDD/BD 的差异。混合症状是网络中最中心和相互连接的节点，特别是激越紧随其后的是易怒。尽管有混合症状，但食欲增加和嗜睡在 BD 患者中更明显，症状之间的关联在 MDD/BD 中高度相关（Spearman's r=0.96，p<0.001）。网络比较检验显示，MDD/BD 在网络强度、结构或特定边缘方面没有显著差异，具有强烈的边缘相关性（0.66-0.78）。MDD/BD 的上游差异可能导致急性抑郁期间下游出现类似的症状网络。然而，混合症状、食欲增加和嗜睡与 BD 相关，而不是 MDD。混合 MDE 期间的症状可能根据 2 个不同的聚类聚集在一起，这表明混合状态中可能存在分层。未来基于症状的研究应纳入临床、纵向和生物学因素，以制定针对急性抑郁的个体化治疗策略。
