Profile of depression in adolescents with inflammatory bowel disease: implications for treatment.

An unresolved problem in pediatric medicine is how to ascertain whether a symptom (e.g., fatigue) is related to a physical illness (e.g., diarrhea in inflammatory bowel disease [IBD]) or an indicator of psychiatric comorbidity, particularly depression. Two strategies utilized in studies of adults with physical illness have been to exclude patients with the most severe physical illness activity (medically hospitalized) and/or eliminating items on the depressive measures utilized that are more prevalent in patients with a specific physical illness.1,2 More recent studies examining depression in physically ill populations have shown that using the entire depressive screen instrument is more valid (e.g., multiple sclerosis,3,4 diabetes,5 cancer,6,7 and depression induced by interferon treatment8). Finally, several studies have shown that such depressive/“sickness” symptoms respond to psychiatric treatment regardless of their etiology.7,8 Such inclusive approaches have been validated in physically ill adults but not in pediatric populations. This study will characterize depression in a pediatric physically ill population to assess if individual depressive symptoms, including the neurovegetative ones, respond to psychosocial intervention using IBD as a model illness. Ulcerative colitis (UC) and Crohn's disease (CD), collectively described as IBD, are challenging gastrointestinal disorders that involve a number of painful and often disabling symptoms such as diarrhea, fever, severe abdominal pain, rectal bleeding, and extraintestinal inflammation. Understanding and coping with such physical challenges can be particularly difficult for youth with IBD, who report reduced health-related quality of life relative to physically healthy peers.9 Research has also shown that youth with IBD are at increased risk for depression relative to physically healthy peers.10-13 Both the inflammatory processes underlying IBD as well as treatment with steroids have been implicated in the etiology of depression in this pediatric population.12 Specifically, the cytokines released during inflammatory states can cause “sickness behaviors” that closely mirror or overlap symptoms of depression.14 Steroid-induced depression has been reported in several other depressive medically ill populations.15 Questions about the etiology of reported neurovegetative symptoms have important implications for treatment planning. If symptoms of physical illnesses such as IBD mimic depression, treatment of these depressive symptoms might not involve psychotherapeutic intervention but instead respond adequately to routine medical care for IBD. As with adult self-report depression inventories, the use of child depression inventories in medical populations creates similar methodological challenges, as these measures often include a number of neurovegetative symptoms. For example, the Children's Depression Inventory (CDI),16 a widely used self-report measure that assesses depressive symptoms in children and adolescents, includes items assessing the following symptoms: sleep, appetite, fatigue, and concern about health. It is one of the most frequently used and well-validated measures of depressive symptoms, and has been used in a wide range of patient populations.16,17 However, research on the application of the CDI in medical populations is lacking, and thus, this study has 2 aims. Aim 1: This present study is the first, to our knowledge, to examine the sensitivity of depression scale items in pediatric IBD in the context of treatment for depression. Based on recent work in adults with multiple sclerosis,4 and youth with IBD,13 we anticipated that a majority of CDI items, including somatic items, would improve over the course of psychotherapeutic treatment. Aim 2: The present study sought to demonstrate that changes in the somatic items on the CDI following psychotherapeutic intervention cannot merely be attributed to changes in objective measures of disease status and/or severity. It was predicted that correlations between changes in the somatic items on the CDI would not be associated with changes in disease severity and/or steroid treatment.