Negative affect as mediator between emotion regulation and medically unexplained symptoms.

<bold>Background: </bold>Research on emotion regulation (ER) in medically unexplained physical symptoms (MUS) is rare.<bold>Purpose: </bold>The goal of this study was to compare ER skills between MUS-patients without comorbid depression, MUS-patients with comorbid depression (MUS+MDD), patients with major depressive disorder (MDD), and healthy controls. Additionally, we examined the mediating effect of depression and anxiety on the relationship between ER and somatization.<bold>Methods: </bold>The Emotion-Regulation Skills Questionnaire (ERSQ) and other self-report measures were completed by 138 MUS-patients, 114 MUS+MDD-patients, 106 MDD-patients, and 100 healthy controls. Multiple mediation analyses were applied to investigate the role of depression and anxiety as potential mediators.<bold>Results: </bold>A MANCOVA and post-hoc test with age, sex and education as covariates indicated that ER skills of the MUS-group were lower than the controls (p<0.001-p=0.047), but higher than the MDD- and MUS+MDD-group (p<0.001-p=0.042). ER skills of the MDD-group and MUS+MDD-group did not differ (p=0.78-p=0.99), but were lower than controls (p<0.001-p=0.011). In the MUS-groups depression and anxiety had a mediating effect on the relationship between ER and somatization (b=-0.23, 95% bias-corrected CI: -0.30, -0.17). The direct effect of ER on somatization was no longer significant when controlling for the mediating variables (b=0.07, p=0.083).<bold>Conclusions: </bold>Our study reveals that patients with MUS+MDD have higher deficits in ER skills than MUS patients without MDD. Additionally, deficits in ER in MUS-patients are influenced by depression and anxiety. This indicates that MUS-patients with comorbid mental disorders might benefit from an emotion regulation training. [ABSTRACT FROM AUTHOR]