Decision making in individuals with anorexia nervosa and individuals with the somatic symptom disorder and the moderating effect of expressive suppression

Objective: The purpose of the current study was to examine if there was impaired decision making in patients with anorexia nervosa (AN) and patients with the somatic symptom disorder (SSD). Thereby, the moderating role of expressive suppression on this relation was investigated. Method: Twelve patients with AN, nineteen patients with SSD and fourteen healthy controls participated in this study. Decision making was measured by the performance on the Iowa Gambling Task (IGT) and expressive suppression was measured by the Emotion Regulation Questionnaire (ERQ). Additionally, relevant characteristics were assessed (e.g. depressive symptoms). Results: The findings indicated that SSD patients performed poorly on the IGT, but no significant differences were found between the groups. Healthy controls show a slightly better learning effect on the IGT compared to both patient groups, but this was not significant. No effect of expressive suppression on decision making was found in the three groups. Conclusion: Our results are not in line with previous research that found a link between AN and impaired decision making, what could be due to confounding factors (e.g. AN subtype). This is the first time decision making of SSD patients is investigated and they show a tendency of a decreasing IGT performance over time. However, there should be more research to draw any conclusions about their decision making of SSD patients. A limitation of the current study is the small sample size, causing power problems. A strength is including different patient groups in the same study.