P784 The direct healthcare costs of Crohn’s disease increased over the last two decades in a Dutch population-based cohort

Abstract

Background: Due to the widespread use of biologicals, medication replaced hospitalisation as major cost driver in Crohn's disease (CD). Whether the use of biologicals merely led to a shift of costs, or also to changes in total costs is unclear. Therefore, we aimed to assess direct costs of CD over the past two decades within the populationbased IBD South Limburg (IBDSL) cohort. Methods: All CD patients registered in the IBDSL cohort with ≥ 1 year of follow-up were included. Three eras were distinguished based on year of diagnosis: '91-'98, '99-'05 and '06-'11. Patients were followed up to 5 years from diagnosis, till loss-to-follow-up or end of data collection (2014). Resource utilisation (i.e. hospitalisation, surgery, diagnostics and medication) was assessed by scrutinising patient files. Cost estimates were calculated in Euro () by multiplying resource use with Dutch reference prices for the corresponding era. Prices were corrected for inflation using consumer price indices. Differences between eras were analysed by one-way ANOVA and Tukey's HSD for post-hoc analysis. Cost differences between years of follow-up were analysed by paired samples t-tests. Log-transformation was used to correct for skewed data. Results: In total, 1108 CD patients were included (301 in era 1991-1998, 377 in era 1999-2005 and 430 in era 2006-2011). Mean total costs per year are presented in Figure 1. For each era, costs were higher in the first year compared with the subsequent years (all p < 0.001). After year 1, costs remained relatively stable, but were higher for each consecutive era (p < 0.001). (Table presented) Mean and median cumulative total costs (CTC) are displayed in Table 1. After 2 years from diagnosis and onwards, mean CTC differed significantly between eras. Post-hoc analysis showed significant differences between the first and the other two eras, but not between the second and third era (Table 1). Mean costs per year (calculated over 5-year follow-up) were 2538, 3889, and 4838, respectively, for the consecutive eras. Conclusions: In this population-based study, direct healthcare costs after the first year were higher for each consecutive era, leading to an increase in total direct costs of CD over time. Future studies should investigate whether this increase is compensated by a decrease in indirect costs (e.g. decreased work disability).