Supporting data for PhD thesis titled "Psychopathology in response to multiple population stressors"

Abstract: A series of large-scale social unrest and co-occurring COVID-19 have erupted in Hong Kong during early 2020. How population-level and personal stressors can interact with intrinsic factors to affect mental health as the events evolve remains to be elucidated.Three symptom dimensions with varying degrees of responsiveness to external stressors were examined throughout this thesis: PTSD and depressive symptoms (more reactive) and psychotic-like experiences (PLEs; typically considered to be more endogenous), with a key focus on ideas of reference (IOR). Event-based rumination, defined as repetitive thoughts about external events, and smartphone overuse were hypothesised to be transdiagnostic mediators between different stressor types and all three psychopathological states. Using timely data collected through a large-scale locally adapted online tool, Study 1 revealed that social unrest-related traumatic events (TEs), COVID-19 events, and personal stressful life events (SLEs) additively and interactively contributed to PTSD and depressive symptoms. Notably, event-based rumination was significantly associated with both symptom dimensions and mediated the effects of all three event types. The predictive capability of event-based rumination for one-month PTSD and depressive symptoms amid such ongoing population-level stressors was further demonstrated in Study 2, highlighting its clinical significance. Study 3 provided novel evidence in showing that IOR experiences, as a form of PLEs, could also be triggered by population-level stressors. While extrinsic factors, such as severe TEs and SLEs, played more prominent roles in attenuated IOR (feeling of being particularly referred to) and intrinsic factors, such as cognitive ability, played more prominent roles in exclusive IOR (feeling of being exclusively referred to), event-based rumination was associated with both spectra of IOR. With a wider range of environmental and personal risk and protective factors considered, Study 4 highlighted the transdiagnostic effects of not only event-based rumination but also smartphone overuse. Some support was found for both these factors as serial mediators between extrinsic events and all three symptom outcomes, although most of the effects were explained by event-based rumination. Smartphone overuse may possibly contribute to symptoms via a separate pathway. Furthermore, the transdiagnostic effects of event-based rumination and smartphone overuse remained robust in both Study 5, using data from a large subgroup of young people further collected through the tool, and in Study 6, using data from an epidemiological youth sample collected one year later (during which TEs have subsided and COVID-19 was ongoing). Using path analysis, the mediating effects of event-based rumination between extrinsic events and IOR severity were again supported, with some of the effects of SLEs on both event-based rumination and IOR severity explained by individual subjective stress. Finally, Study 7 offered initial evidence suggesting IOR experiences as a higher class of psychopathology. Symptom network analysis revealed that event-based rumination also contributed to specific symptom-level associations between IOR and both PTSD and depressive symptoms. The increasingly observed co-occurring large-scale crises globally demands valid, context-relevant, agile, and timely action. It is hoped this thesis could inform these future work.

摘要：2020年初，香港爆发了一系列大规模的社会动荡，与COVID-19疫情同时发生。随着事件的发展，探讨人口层面的压力因素和个人压力因素如何与内在因素相互作用，以影响心理健康，仍需进一步阐明。本论文考察了三个不同程度对外部压力因素有反应的症状维度：创伤后应激障碍和抑郁症状（更具反应性）以及精神病性体验（PLEs；通常被认为更具内生性），重点关注参照理念（IOR）。基于事件的沉思，定义为对外部事件的重复思考，以及智能手机过度使用，被假定为不同压力类型和所有三种心理病理状态之间的跨诊断性中介因素。利用通过大规模本地化在线工具收集的及时数据，研究1揭示了与动荡相关的创伤事件（TEs）、COVID-19事件和个人压力生活事件（SLEs）对创伤后应激障碍和抑郁症状的累加和交互性贡献。值得注意的是，基于事件的沉思与这两个症状维度显著相关，并中介了所有三种事件类型的影响。研究2进一步证明了基于事件的沉思在持续的人口层面压力因素下，对一个月后的创伤后应激障碍和抑郁症状的预测能力，凸显了其临床意义。研究3提供了新颖的证据，表明作为PLEs的一种形式的参照理念体验，也可能由人口层面的压力因素触发。尽管外在因素，如严重的TEs和SLEs，在缓解型参照理念（特别指感）中发挥更显著的作用，而内在因素，如认知能力，在独占型参照理念（独指感）中发挥更显著的作用，但基于事件的沉思与两种参照理念谱系均相关。在考虑更广泛的环境和个人风险和防护因素后，研究4突出了不仅基于事件的沉思，而且智能手机过度使用的跨诊断效应。这两种因素作为外在事件和所有三种症状结果之间的连续中介因素的支持得到证实，尽管大多数效应由基于事件的沉思解释。智能手机过度使用可能通过一条单独的途径导致症状。此外，基于事件的沉思和智能手机过度使用的跨诊断效应在研究5（使用通过工具进一步收集的大规模青年子组的数据）和研究6（使用一年后收集的流行病学青年样本的数据，在此期间TEs已平息，COVID-19仍在持续）中均保持稳健。利用路径分析，再次支持了基于事件的沉思在外在事件和参照理念严重程度之间的中介效应，其中SLEs对基于事件的沉思和参照理念严重程度的一些影响可通过个人主观压力解释。最后，研究7提供了初步证据，表明参照理念体验作为一种高级心理病理学。症状网络分析揭示了基于事件的沉思还促进了参照理念与创伤后应激障碍和抑郁症状之间的特定症状水平关联。全球日益观察到的并发大规模危机要求有效的、与背景相关的、敏捷的和及时的行动。希望本论文能够为未来的工作提供信息。