The role of cognitive factors in differentiating individuals with somatoform disorders with and without depression

The present study, based on a cross-sectional design, was conducted in the primary care setting with patients presenting somatic symptoms suggestive of somatoform disorders (SFD). The main aim of the study was to determine whether cognitive variables could differentiate between patients with SFD alone and those who also present depressive symptoms suggestive of depression (SFD + depression). All participants (N = 796) completed validated self-report measures to assess somatic, depressive, and/or anxiety symptoms, as well as functional impairment, quality of life (QoL), and cognitive variables (worry, rumination, metacognition, cognitive distortions, and emotion regulation). Univariate and multivariate analyses (controlled for potential sociodemographic and clinical confounders) were performed. On the univariate analysis, significant differences between the SFD and SFD + depression groups were found in sociodemographic and clinical variables, functional impairment, QoL, and cognitive variables. On the multivariate analysis, the only significative variables associated with comorbid SFD + depression were anxiety (β = 0.27; p < 0.001), physical and psychological QoL (β = -0.10; p = 0.01; and β = -0.21; p < 0.001, respectively), and marital status (β = -65; p < 0.05). Cognitive variables were not significantly related to depressive symptoms in patients with SFD. These findings suggest that patients with SFD - with or without comorbid depression - share common cognitive processes and thus both groups could benefit from transdiagnostic cognitive therapy.