The role of thought suppression in conversion disorder in relation to depression, symptom interpretation and sleep hygiene: a case-control study

Abstract Background Thought suppression has been associated with a number of psychiatric disorders. However, the association with conversion disorder (CD) has not been investigated yet. Objective To investigate the role of thought suppression in CD. Methods Eighty consecutive outpatients with a diagnosis of CD and sixty age, sex and neighborhood-similar controls were evaluated using Beck Depression Inventory-I (BDI-I), White Bear Suppression Inventory (WBSI), Symptom Interpretation Questionnaire (SIQ) and Sleep Hygiene Index (SHI). Cases and controls were compared in regard to thought suppression scores considering their status of high depression scores via a logistic regression model. The reciprocal associations of thought suppression with other clinical dimensions in CD were assessed. Finally, structural equation modelling was applied to untangle the possible connections. Results CD patients had significantly higher scores of thought suppression than the control group. However, the difference was below the significance level when CD patients without comorbid high depression scores were taken into account. Thought suppression was associated with the clinical severity of CD. According to the structural equation model, older age and somatic attributions to the common bodily sensations were the significant correlates of thought suppression among CD patients. Discussion Thought suppression may be considered as a non-specific marker of clinical severity in CD.摘要：思维抑制（thought suppression）与多种精神障碍存在关联，但目前尚未有针对其与转换障碍（conversion disorder, CD）之间关联的研究。本研究旨在探讨思维抑制在转换障碍中的作用。方法：连续纳入80例确诊为转换障碍的门诊患者，以及60例年龄、性别与居住地区匹配的对照者，采用贝克抑郁量表第一版（Beck Depression Inventory-I, BDI-I）、白熊思维抑制量表（White Bear Suppression Inventory, WBSI）、症状归因问卷（Symptom Interpretation Questionnaire, SIQ）以及睡眠卫生指数（Sleep Hygiene Index, SHI）对所有受试者进行评估。通过logistic回归模型，按抑郁评分高低分组，对比病例组与对照组的思维抑制评分差异；同时评估转换障碍患者中思维抑制与其他临床维度的双向关联；最终应用结构方程模型厘清潜在的关联通路。结果：转换障碍患者的思维抑制评分显著高于对照组。但若仅纳入无共病高抑郁评分的转换障碍患者进行分析，该差异未达到统计学显著性水平。思维抑制与转换障碍的临床严重程度相关。结构方程模型分析显示，在转换障碍患者中，年龄更大以及对普通躯体感觉的躯体归因是思维抑制的显著相关因素。讨论：思维抑制可被视为转换障碍临床严重程度的非特异性标志物。