| Several theories have attempted to understand the etiology of affective episodes, but many have not been validated. For example, the social zeitgeber theory suggests that affective symptoms are caused by life events disrupting vulnerable individuals' social and biological rhythms (Ehlers, Frank, & Kupfer, 1988). Preliminary evidence suggests that social rhythm disrupting life events may precede manic episodes (Malkoff-Schwartz et al., 1998; 2000) and that increasing bipolar individuals' social rhythm regularity may buffer them from their next affective episode (Frank et al., 2005). The aim of the current study was to examine several of the hypothesized causal associations of the social zeitgeber theory, specifically, whether life events impact social rhythm regularity and mood episodes, and whether social rhythm regularity predicts affective symptomatology and episodes. Participants were selected from an undergraduate college population based on their self-reported symptomatology and met criteria for the study based on a structured lifetime diagnostic interview. The final sample consisted of 101 bipolar spectrum participants and 100 demographically matched normal controls. Participants completed self-report symptom and social rhythm questionnaires as well as diagnostic and life event interviews approximately every four months. The first three prospective follow-up visits were analyzed in this study. The results showed that life events did not predict social rhythm regularity, but life events did predict affective symptoms. There was less of a consistent relationship between life events and hypo(manic) symptoms and episodes. There were also inconsistent associations between social rhythm regularity and affective symptoms and episodes. This study is the first to examine several hypothesized causal associations of the social zeitgeber theory in a bipolar spectrum sample. The current study yields mixed support for the social zeitgeber theory in that life stress, particularly life events that disrupt one's social rhythm regularity, predicted bipolar symptoms and episodes. However, a retrospective measure of social rhythm regularity did not predict affective symptomatology and episodes and social rhythm regularity was not predicted by life stress. Thus, future research is needed to further ascertain the validity of the social zeitgeber theory. Such research would further our understanding of bipolar disorder as well as offer potentially effective treatment interventions. |
