Chronobiological dis-rhythmicity is related to emotion dysregulation and suicidality in depressive bipolar II disorder with mixed features

In Bipolar Disorder, chronobiological rhythm alterations play a key role by negatively influencing its entire trajectory. Our aim was to assess their potential association with emotion dysregulation and suicidality in subjects with Bipolar Disorder. Eighty-five patients with Bipolar Disorder - II depressive episode with mixed features were recruited and 35 as healthy controls. Subjects were evaluated with SCID-DSM-5, the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN), the DERS: Difficulties in Emotion Regulation Scale, the Beck Depression Inventory-II (BDI-II), the Young Mania Rating Scale (YMRS) and the Scale for Suicide Ideation (SSI). When compared to healthy controls, subjects with bipolar disorder showed significantly higher scores in the BRIAN, the DERS, the BDI-II, the YMRS and the SSI total scores. Chronobiological dis-rhythmicity was significantly related to the severity of depressive symptoms, emotion dysregulation, and suicidality in bipolar individuals. In particular, the dis-rythmicity of the sleep/wake pattern showed a significant correlation with manic symptoms, the dis-rythmicity of daily activities with depressive symptoms and emotion dysregulation and that of social life with suicidality. Emotion dysregulation played as a mediator for the association between chronobiological dis-rhythmicity and depressive symptoms (mediated effect = 3.25, p = 0.001) and for social life dis-rhythmicity and suicidality (mediated effect = 2.52, p = 0.011) as well. Therefore, our findings showed that chronobiological dis-rhythmicity in bipolar individuals was related to the severity of mood swings, emotion dysregulation and suicidality. The assessment of potential alteration in chronobiological rhythms should be investigated in the clinical setting in subjects with bipolar disorder to identify those who may benefit from early chronobiological intervention.