Self-schema in irritable bowel syndrome and depression

Some investigators have suggested that irritable bowel syndrome (IBS) represents a physiologic expression of an affective disorder. This study investigated whether IBS patients differed in their self-schema from depressed patients. Self-schema refers to a cognitive framework of the individual's beliefs, attitudes, and self-perceptions which is stored in memory and which influences incoming information. The sample consisted of 21 IBS patients, 21 psychiatric outpatients with major depression (MD), and 19 normal controls. All groups were age matched. Subjects completed a structured psychiatric interview (Diagnostic Interview Schedule (DIS) and a Beck Depression Inventory (BDI), in addition to a test of self-schema, which involved rating and recall of a variety of "depressed" and "nondepressed" content adjectives. Consistent with previous work on self-schema, the MD group recalled significantly more depressed adjectives rated under the self-referent task than the Control group (p less than 0.05) and, also, the IBS group (p less than 0.05). Most striking was the finding that a subgroup of IBS patients who met criteria for MD (43% of the sample) recalled significantly more self-referent nondepressed words (and less self-referent depressed words) than the MD group (p less than 0.05). In other words, IBS patients with MD do not view themselves as depressed. These findings suggest that while some IBS and depressed psychiatric outpatients may share depressive symptoms, these groups can be differentiated by their self-schema.