Controversies surrounding the comorbidity of depression and anxiety in inflammatory bowel disease patients: a literature review

Psychological disorders are highly prevalent in patients with inflammatory bowel disease (IBD). Anxiety and depression are known to independently affect quality of life and may additionally impair quality of life in IBD over and above the IBD itself. Some researchers have further proposed that anxiety and depression may influence the clinical course of IBD. However, despite the potential for anxiety and depression to play an important role in the clinical picture of IBD, there is little prospective well-controlled research in this area. Probably because of this lack of clear data, researchers dispute the actual role of these psychological disorders in IBD, with a number of conflicting opinions expressed. This article reports on a review of the literature in this field. Herein we discuss the five main areas of controversy regarding IBD and the specific psychological comorbidities of depression and anxiety: 1) the relative rate of cooccurrence of these psychological disorders with IBD; 2) the cooccurrence of these psychological disorders with particular phase of IBD; 3) the cooccurrence of these psychological disorders with the specific type of IBD; 4) the rate of these psychological comorbidities compared both to healthy subjects and to other disease states; and 5) the timing of onset of psychological comorbidity with respect to onset of IBD. Methodological weaknesses of the reviewed studies make it impossible to resolve these controversies. However, the results clearly show that anxiety/depression and IBD frequently interact. Given the long-term illness burden patients with IBD face, further prospective, appropriately controlled studies are needed to adequately answer the question of the precise interplay between anxiety/depression and IBD.