Desert Pacific Mental Illness Research, Education and Clinical Center, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California.
Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles.
JAMA Psychiatry. 2022 Oct 1;79(10):1014-1022. doi: 10.1001/jamapsychiatry.2022.2386.
Improved understanding of the boundaries and connections between positive symptoms, negative symptoms, and role functioning in schizophrenia is critical, given limited empirical support for clear distinctions among these clinical areas. This study's use of network psychometrics to investigate differential associations and structural overlap between positive symptoms, negative symptoms, and functional domains in schizophrenia may contribute to such understanding.
To apply network analysis and community detection methods to examine the interplay and structure of positive symptoms, negative symptoms, and functional domains in individuals with schizophrenia.
DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study in 5 geographically distributed research centers in the US as part of the Consortium on the Genetics of Schizophrenia-2 from July 1, 2010, through January 31, 2014. Data were analyzed from November 2021 to June 2022. Clinically stable outpatients with schizophrenia or schizoaffective disorder were included. Participants were excluded if they had evidence of neurologic or additional Axis I psychiatric disorders. Other exclusion criteria included head injury, stroke, and substance abuse. Of 1415 patients approached, 979 were included in the final analysis.
Measures included the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, and the Role Functioning Scale. Main outcomes were expected influence, which assesses the relative importance of items to the network and is defined as the association of an item with all others, and community detection and stability, defined as the presence of statistical clusters and their replicability.
Participants with complete data included 979 outpatients (mean [SD] age, 46 [11] years; 663 male [67.7%]; 390 participants [40%] self-identified as African American, 30 [3%] as Asian, 7 [0.7%] as Native American, 8 [0.8%] as Pacific Islander, 412 [42.1%] as White, 125 [12.8%] as more than 1 race, and 5 [0.5%] did not identify). Anhedonia had the highest expected influence in the most comprehensive network analysis, showing connections with negative and positive symptoms and functional domains. Positive symptoms had the lowest expected influence. Community detection analyses indicated the presence of 3 clusters corresponding to positive symptoms; negative symptoms and work functioning; functional domains, including independent living, family relationships, and social network; and avolition, anhedonia, and work functioning. Hallucinations and delusions replicated in 1000 bootstrapped samples (100%), while bizarre behavior and thought disorder replicated in 390 (39%) and 570 (57%), respectively. In contrast, negative symptoms and work functioning replicated between 730 (73%) and 770 (77%) samples, respectively, and the remaining functional domains in 940 samples (94%).
The high centrality of anhedonia and its connections with multiple functional domains suggest that it could be a treatment target for global functioning. Interventions for work functioning may benefit from a specialized approach that focuses primarily on avolition.
鉴于目前对这些临床领域之间的明确区分的实证支持有限，因此，深入了解精神分裂症中阳性症状、阴性症状和角色功能之间的边界和联系至关重要。本研究使用网络心理计量学来研究精神分裂症个体中阳性症状、阴性症状和功能领域之间的差异关联和结构重叠，这可能有助于对此进行理解。
应用网络分析和社区检测方法来研究精神分裂症个体中阳性症状、阴性症状和功能领域之间的相互作用和结构。
设计、地点和参与者：这是一项在美国 5 个地理分布的研究中心进行的横断面研究，是精神分裂症遗传学联合会-2 的一部分，时间为 2010 年 7 月 1 日至 2014 年 1 月 31 日。数据分析于 2021 年 11 月至 2022 年 6 月进行。纳入了患有精神分裂症或分裂情感障碍的临床稳定门诊患者。如果患者有神经或其他轴 I 精神障碍的证据，则将其排除在外。其他排除标准包括头部受伤、中风和物质滥用。在接触的 1415 名患者中，有 979 名被纳入最终分析。
测量指标包括阳性症状评定量表、阴性症状评定量表和角色功能量表。主要结局是预期影响，它评估了项目对网络的相对重要性，定义为项目与所有其他项目的关联；社区检测和稳定性，定义为存在统计聚类及其可重复性。
在有完整数据的参与者中，包括 979 名门诊患者（平均[标准差]年龄，46[11]岁；663 名男性[67.7%]；390 名参与者[40%]自我认定为非裔美国人，30 名[3%]为亚裔美国人，7 名[0.7%]为美国原住民，8 名[0.8%]为太平洋岛民，412 名[42.1%]为白人，125 名[12.8%]为多种族，5 名[0.5%]未识别）。在最全面的网络分析中，快感缺失的预期影响最高，与阴性和阳性症状以及功能领域均有联系。阳性症状的预期影响最低。社区检测分析表明存在 3 个与阳性症状、阴性症状和工作功能、功能领域（包括独立生活、家庭关系和社会网络）以及意志缺失、快感缺失和工作功能对应的聚类。幻觉和妄想在 1000 次 bootstrap 样本（100%）中重现，而怪异行为和思维障碍在 390（39%）和 570（57%）个样本中重现。相比之下，阴性症状和工作功能在 730（73%）和 770（77%）个样本中重现，其余功能领域在 940 个样本（94%）中重现。
快感缺失的中心性很高，且与多个功能领域相关，这表明它可能是全面功能的治疗靶点。工作功能的干预措施可能受益于一种专门的方法，该方法主要侧重于意志缺失。
