We examined the interaction of cognitive styles and life events in predicting the depressive and hypomanic mood swings of 43 undergraduates meeting criteria for a subsyndromal mood disorder (i.e., cyclothymia, dysthymia, or hypomania) or no lifetime diagnosis. Participants completed symptom, cognitive style, and life events measures on three separate occasions as the different mood states characteristic of their subsyndromal disorder naturally occurred. Normal controls were assessed in three separate normal mood states at times yoked to participants in the three disorder groups. All groups' attributional styles and dysfunctional attitudes remained stable across large changes in mood and symptomatology and cyclothymics' cognitive styles were as negative as those of dysthymics. Moreover, hierarchical regression analyses indicated that participants' attributional styles, as measured in a normal mood state (Time 1), in interaction with intervening life events predicted prospectively their depressive symptom changes at Times 2 and 3 and their hypomanic symptom changes at Time 2. These findings provide support for the cognitive vulnerability-stress hypothesis of the Hopelessness theory of depression (Abramson, Metalsky, & Alloy, 1989) and suggest that the logic of the Hopelessness theory's vulnerability-stress hypothesis extends to the prediction of manic/hypomanic symptoms.
Cognitive vulnerability-stress theories of depression, in particular the Hopelessness theory (Abramson, Metalsky, & Alloy, 1989) and Beck's (1967) theory, include the hypothesis that maladaptive cognitive styles act as vulnerabilities that increase people's risk for depression when they confront stressful life events. Whereas much research has examined the role of cognitive styles and life events in the onset and course of unipolar depression (e.g., Abramson, Alloy, & Metalsky, 1995; Haaga, Dyck, & Ernst, 1991), little is known about the role of these factors in the prediction of manic or hypomanic symptomatology. Yet, recent research suggests that the cognitive theories of unipolar depression may be applied fruitfully to bipolar disorders as well (e.g., Hammen, Ellicott, & Gitlin, 1992). Thus, the major goal of the present study was to examine whether the interaction of cognitive styles and life events would predict the severity of manic/hypomanic symptoms as well as depressive symptoms among individuals with unipolar and bipolar subsyndromal mood disorders.
Three subsyndromal mood disorders have been included in the Diagnostic and Statistical Manual of Mental Disorders since the third edition (DSM-III, American Psychiatric Association, 1980). Cyclothymia is a subsyndromal form of bipolar disorder and is often the precursor to the later development of full-blown bipolar disorder (Goodwin & Jamison, 1990). A diagnosis of cyclothymia involves intermittent episodes shifting between dysphoric mood and symptoms characteristic of depression and euphoric mood and symptoms characteristic of hypomania. Dysthymia represents the subsyndromal and chronic form of unipolar depression (Akiskal, 1997) and is manifested by intermittent periods of depressed mood and symptoms. Finally, recurrent hypomania is characterized by shifts between normal and elevated mood states much like in unipolar mania. Whereas pure manics are thought to be rare (but see Abrams & Taylor, 1974 for an alternative view), recurrent bouts of hypomania may be more common (Goodwin & Jamison, 1990). Although subsyndromal disorders involve less severe mood episodes than their full sy ndromal counterparts, subsyndromal mood disorders can also disrupt functioning in many domains and lead to impairment (Akiskal, 1997; Goodwin & Jamison, 1990).
Although little prior research has investigated the role of cognitive patterns and life events in manic or bipolar disorders, recent empirical evidence and theorizing from the standpoint of the cognitive theories of depression suggest that certain cognitive styles and life events are likely to contribute to manic/hypomanic symptoms as well as depressive symptoms. …