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

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.