The prevalence and outcomes of exposure to potentially traumatic stressful life events compared across patients with bipolar disorder and unipolar depression

This study examined the profile of stressful life experiences in patients with unipolar depression (UP) compared to bipolar disorder (BP), including their subsequent psychological impact and affirmation of post-traumatic stress symptoms. We studied 747 tertiary patients diagnosed with either a UP (n = 413) or BP condition (n = 334) according to a structured research interview and psychiatrist assessment. An online assessment collected additional study variables. Results showed that despite being younger in age, the BP group were more likely to have experienced 8 of the stressful life events, including childhood and adulthood abuse. However, both groups judged the consequential 'impact' of those events similarly. The BP group was significantly more likely than the UP group (45% vs. 36%) to affirm exposure to an extremely stressful event across their lifetime, resulting in 26.3% of the BP and 14.5% of the UP group affirming DSM-IV criteria for lifetime PTSD. The onset of DSM-IV-defined post-traumatic symptoms tended to occur in adulthood for both groups, with trauma often following the onset of the mood disorder. Thus, BP patients displayed greater vulnerability toward traumatic experiences and anxiety disorders, but reported a similar psychological impact in response to each stressor, compared with the UP group.