The role of intolerance of uncertainty in bipolar disorder

Intolerance of uncertainty (IU) is a dispositional trait arising from negative beliefs about uncertainty. IU has been found to be associated with various psychological disorders, including anxiety and depression, but little is known about its role in bipolar disorder (BD). The present study investigates the presentation of IU in BD, including exploring its relationship with mania and impulsivity.

Participants with a self-reported diagnosis of BD (n = 93), unipolar depression (n = 90) and control participants (n = 91) were recruited from a participant recruitment platform to complete an online survey. Groups were compared on a variety of measures, including IU, mania symptoms, impulsivity and neuroticism, and a correlation analysis was performed to examine the relationships between IU and mania as well as IU and impulsivity.

BD participants scored higher than depression participants and controls on all measures except neuroticism, which was found to be equivalent to the depression group. IU positively correlated with mania even when neuroticism was controlled for. IU positively correlated with impulsivity but only in the BD group, and this effect was lost when neuroticism was controlled for.

This study provides evidence for the possible importance of IU as a higher-order factor in BD, which extends our understanding of the disorder. Findings could pave the way to explaining why anxiety is prevalent in BD and provide opportunities for an increase in the effectiveness of treatments.