Kindling of Life Stress in Bipolar Disorder: Effects of Early Adversity

- The impact of stressful life events in triggering mood episodes in bipolar disorder differs between individuals
- Research on the kindling hypothesis has been extended to childhood adversity, which not been examined in Bipolar Disorder
- In Bipolar Disorder, greater adversity was associated with a lower threshold for life stress to trigger a depressive episode
- Among people with bipolar disorder greater child adversity was associated with a lower threshold for life stress to trigger a depressive episode
- Results support the kindling effect of early adversity in bipolar disorder

Most theoretical frameworks regarding the role of life stress in bipolar disorders (BD) do not incorporate the possibility of a changing relationship between psychosocial context and episode initiation across the course of the disorder. The kindling hypothesis theorizes that over the longitudinal course of recurrent affective disorders, the relationship between major life stressors and episode initiation declines (Post, 1992). The present study aimed to test an extension of the kindling hypothesis in BD by examining the effect of early life adversity on the relationship between proximal life events and prospectively assessed mood episodes. Data from 145 bipolar participants (59.3% female, 75.2% Caucasian, and mean age of 20.19 years; SD = 1.75 years) were collected as part of the Temple-Wisconsin Longitudinal Investigation of Bipolar Spectrum Project (112 Bipolar II; 33 Cyclothymic disorder). Participants completed a self-report measure of early adversity at baseline and interview-assessed mood episodes and life events at regular 4-month follow-ups. Results indicate that early childhood adversity sensitized bipolar participants to the effects of recent stressors only for depressive episodes and not hypomanic episodes within BD. This was particularly the case with minor negative events. The current study extends prior research examining the kindling model in BD using a methodologically rigorous assessment of life stressors and mood episode occurrence. Clinicians should assess experiences of early adversity in individuals with BD as it may impact reactivity to developing depressive episodes in response to future stressors.