The impact of major depressive disorder on the short- and long-term outcome of Crohn's disease treatment with infliximab

Background: Major depressive disorder is the most common psychiatric diagnosis in Crohn's disease. In other chronic diseases, evidence suggests that depression influences the course of the disease. Strong evidence of such a mediating role of major depressive disorder in Crohn's disease has never been found. Aim: To assess the relationship between major depressive disorder and outcome of treatment of luminal Crohn's disease with infliximab. Methods: In this prospective study, 100 consecutive unselected patients underwent assessment of psychosocial, demographical disease-related biological and clinical parameters at baseline and at 4 weeks after infliximab. Major depressive disorder was diagnosed using the Patient Health Questionnaire. Subsequently, the patients were followed up clinically until the next flare or during 9 months. Results: The Crohn's disease responded in 75% of the patients, and remission was achieved in 60%. The presence of major depressive disorder at baseline predicted a lower remission rate ( OR 0.166, 95% CI = 0.049 - 0.567, P = 0.004). At follow-up, 88% of the patients needed retreatment. At univariate regression analysis, major depressive disorder significantly decreased time to retreatment (P = 0.001). Multivariate Cox regression confirmed major depressive disorder as an independent determinant of active disease both at baseline and at re-evaluation ( hazard ratio = 2.271, 95% CI: 1.36 - 3.79, P = 0.002). Conclusion: Major depressive disorder is a risk factor for failure to achieve remission with infliximab and for earlier retreatment in patients with active luminal Crohn's disease. Assessment and management of major depressive disorder should be part of the clinical approach to patients with Crohn's disease.