Introduction: Inflammatory bowel disease (IBD) is a chronic condition that afflicts young adults in their economically productive years. The goal of this study was to determine the costs of IBD in Germany from a societal perspective, using cost diaries.
Methods: Members of the German Crohn's Disease and Ulcerative Colitis Association who had IBD were recruited by post, and those who agreed to participate documented their IBD-associated costs prospectively in a diary over 4 weeks. They documented their use of healthcare facilities, medications, sick leave and out-of-pocket expenditures, as well as general demographic information, the status and history of their IBD, and long-term disability. Item costs were calculated according to national sources. Cost data were calculated using non-parametric bootstrapping and presented as mean costs (year 2004) over 4 weeks.
Results: The cost diaries were returned by 483 subjects (Crohn's disease: n = 241, ulcerative colitis: n = 242) with a mean age of 42 years and an average disease duration of 13 years (SD +/- 8.09). The cost diaries were regarded as 'easy to complete' by 89% of participants. The mean 4-week costs per subject were 1,425 Euros(95% CI 1201, 1689) for Crohn's disease and 1,015 Euros(95% CI 832, 1258) for ulcerative colitis. Of the total costs for Crohn's disease, 64% were due to indirect costs such as early retirement or sick leave and 32% were due to direct medical costs. In contrast, of the total costs for ulcerative colitis, 41% were due to direct medical costs and 54% to indirect costs.
Conclusions: This is the first comprehensive cost study for Crohn's disease and ulcerative colitis in Germany. The most important economic factors that influenced the cost profiles of both diseases were the long-term productivity losses due to an ongoing inability to work and the cost of medications. Results indicate significant cost differences between Crohn's disease and ulcerative colitis. This data provides initial cost estimates that can be analysed further with respect to cost determinants and disease-specific costs in the future.